Patent Publication Number: US-11651555-B2

Title: Re-creation of virtual environment through a video call

Description:
BACKGROUND 
     A networked meeting represents one popular form of electronic collaboration that facilitates communication between two or more participants present at separate physical locations. Participants of a communication session in a networked meeting are able to exchange live video, audio, and other types of content to view, hear, and otherwise share information. Participants can also view a common space, e.g., a whiteboard or a shared application, through which ideas can be exchanged. Viewing of the common space can be complemented with a video and audio conference, an instant messaging session, or any combination thereof, such that the networked meeting can act as a near substitute for an in-person meeting. 
     As networked meetings have become ubiquitous, the types of devices that can be used to participate in networked meetings has increased. While once limited to desktop and laptop computers, users can now participate in networked meetings using many other types of hardware devices including, but not limited to, smartphones, tablet computing devices, set-top boxes, smart televisions, video game systems, and even augmented reality (“AR”), virtual reality (“VR”), and mixed reality (“MR”) devices. 
     When a participant utilizes an AR device to participate in a networked meeting, it is currently possible for the AR device to capture that participant&#39;s view of their surrounding environment and transmit images or video of the view to the other meeting participants. The other meeting participants can then be presented with the images or video of the real-world environment surrounding the user wearing the AR device. The other meeting participants might also be able to view any virtual objects that the AR device has overlaid upon the real-world environment. 
     Despite the benefits of the features described above, some systems have drawbacks. For example, the images or video of the real-world environment may be limited to a perspective of the AR device (also referred to as a ‘pose’ of the AR device). While the perspective may be changed, e.g. by the wearer of the AR device moving about or looking around, other meeting participants are then limited to the new perspective. It can be appreciated that there is an ongoing need to improve techniques for allowing users to efficiently view objects, real and virtual, from other perspectives. 
     It is with respect to these considerations and others that the disclosure made herein is presented. 
     SUMMARY 
     An improved human-computer interface (“HCI”) is disclosed herein for viewing a three-dimensional (“3D”) representation of a real-world environment from different, changing, and/or multiple perspectives. An AR device may capture, in real-time, a 3D representation of a scene using a surface reconstruction (“SR”) camera and a traditional Red Green &amp; Blue (“RGB”) camera. The 3D representation may be transmitted to and viewed on a user&#39;s computing device, enabling the user to navigate the 3D representation. The user may view the 3D representation in a free-third-person mode, enabling the user to virtually walk or fly through the representation captured by the AR device. The user may also select a floor plan mode for a top-down or isomorphic perspective. Enabling a user to view a scene from different perspectives enhances understanding, speeds trouble-shooting, and fundamentally improves the capability of the computing device, the AR device, and the combination thereof. 
     In some embodiments, the computing device displaying the 3D representation may display multiple perspectives and/or multiple modes at the same time (e.g. third person, top-down, etc.). Multiple perspectives may be created by assigning virtual cameras to different locations and orientations within the scene. In some embodiments, the different perspectives/modes may be displayed on different computing devices. For example, a desktop computer may display an isometric floor-plan for the user while the user wears a 3D-enabled headset (e.g. an AR/VR/MR headset) in a free-third-person mode. In some embodiments, the 3D-enabled headset is associated with a virtual camera, while the location of the virtual camera is displayed on the floor-plan. As the user moves the 3D-enabled headset, the location of the virtual camera is updated, updating the perspective of the virtual camera and the location of the virtual camera on the floor-plan. In this way, the user is enabled to see their location on the floor-plan as they navigate the scene. 
     In some embodiments, real-time data used to generate the 3D representation may be augmented by data captured in the past. For example, as the AR device wearer moves or looks around, a 3D representation of the scene is captured from different perspectives. Data from these different perspectives may be integrated into the 3D representation, enabling the user to view more of the scene than the immediate perspective of the AR device. Similarly, data captured with other devices, live or from the past, may also be integrated into the 3D representation. In some embodiments the other device is a stationary camera. In other embodiments, the other device is another AR device worn by another meeting participant, enabling perspectives from multiple meeting participants to be integrated into the 3D representation. 
     In some embodiments, a history of the 3D environment as it was recorded over time is saved, such that the user may pause, rewind, and fast-forward the 3D representation. This enables a 4 th  dimensional component of the navigation, allowing the user to replay a scene from different perspectives. For example, if the AR device wearer drops a bolt and it gets away from him, the user may search the 3D environment from multiple perspectives and from multiple points in time to track down the missing bolt. 
     The HCI disclosed herein can enable users to efficiently investigate and/or navigate a 3D representation of a real-world environment, independent of the perspectives of one or more cameras used to generate the 3D representation. This can result in more efficient use of computing resources such as processor cycles, memory, network bandwidth, and power, as compared to previous solutions. Other technical benefits not specifically mentioned herein can also be realized through implementations of the disclosed subject matter. 
     In order to realize the technical benefits mentioned briefly above, and potentially others, a computing device configured with sensors and program code capable of 3D spatial mapping, such as an AR device or appropriately-configured smartphone, generates mesh data that defines a 3D representation of a real-world environment. The computing device also generates still or moving images (i.e. a video) of the real-world environment. Such a computing device can also be utilized to augment a user&#39;s view of the real-world environment with virtual objects. The virtual objects appear as if they are actually present in the real-world environment when the real-world environment is viewed with the computing device. The computing device transmits the mesh data and images to a remote computing device over a suitable data communications network. 
     It should be appreciated that various aspects of the subject matter described briefly above and in further detail below can be implemented as a hardware device, a computer-implemented method, a computer-controlled apparatus or device, a computing system, or an article of manufacture, such as a computer storage medium. While the subject matter described herein is presented in the general context of program modules that execute on one or more computing devices, those skilled in the art will recognize that other implementations can be performed in combination with other types of program modules. Generally, program modules include routines, programs, components, data structures, and other types of structures that perform particular tasks or implement particular abstract data types. 
     Those skilled in the art will also appreciate that aspects of the subject matter described herein can be practiced on or in conjunction with other computer system configurations beyond those specifically described herein, including multiprocessor systems, microprocessor-based or programmable consumer electronics, AR, VR, and MR devices, video game devices, handheld computers, smartphones, smart televisions, self-driving vehicles, smart watches, e-readers, tablet computing devices, special-purpose hardware devices, network appliances, and the others. 
     Features and technical benefits other than those explicitly described above will be apparent from a reading of the following Detailed Description and a review of the associated drawings. This Summary is provided to introduce a selection of concepts in a simplified form that are further described below in the Detailed Description. This Summary is not intended to identify key or essential features of the claimed subject matter, nor is it intended to be used as an aid in determining the scope of the claimed subject matter. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG.  1    is a computing system diagram illustrating aspects of an operating environment for the embodiments disclosed herein along with aspects of an illustrative HCI that enables a 3D representation of a real-world environment through a video call, according to one embodiment disclosed herein. 
         FIG.  2    is a computing system diagram illustrating a user viewing a 3D representation of a scene from a perspective other than the perspective of the camera capturing the scene. 
         FIG.  3    is a computing system diagram illustrating two computing devices simultaneously displaying two different perspectives of a 3D representation of the scene. 
         FIG.  4    is a computing system diagram illustrating a location of a virtual camera on a floor-map of a 3D representation of the scene. 
         FIG.  5    is a computing system diagram illustrating a 3D representation of the scene that has been integrated with data captured in the past. 
         FIG.  6    is a computing system diagram illustrating a 3D representation of the scene that has been integrated with data captured by a second camera. 
         FIG.  7    is a computing system diagram illustrating aspects of a routine for rendering different perspectives of a 3D environment. 
         FIG.  8    is a computing system diagram showing aspects of an illustrative operating environment for the technologies disclosed herein. 
         FIG.  9    is a computing architecture diagram showing aspects of the configuration and operation of a computing device that can implement aspects of the technologies disclosed herein. 
         FIG.  10    is a computing device diagram showing aspects of the configuration and operation of an AR device that can implement aspects of the disclosed technologies, according to one embodiment disclosed herein. 
     
    
    
     DETAILED DESCRIPTION 
     The following Detailed Description describes an improved human-computer interface (“HCI”) for viewing a three-dimensional (“3D”) representation of a real-world environment from different, changing, and/or multiple perspectives. As mentioned above, the disclosed HCI can capture a 3D representation of a scene using an augmented reality device, transmit the 3D representation to a computing device, and then render on the computing device a different perspective of the 3D representation. This can result in more efficient use of computing resources such as processor cycles, memory, network bandwidth, and power, as compared to previous solutions for viewing multiple perspectives of a scene that utilized different cameras and different video streams for each perspective viewed by the computing device. Technical benefits other than those specifically described herein might also be realized through implementations of the disclosed technologies. 
     As discussed briefly above, a networked meeting represents one popular form of electronic collaboration that utilizes an application program (e.g., CISCO WEBEX provided by CISCO SYSTEMS, Inc. of San Jose, Calif., GOTOMEETING provided by CITRIX SYSTEMS, INC. of Santa Clara, Calif., ZOOM provided by ZOOM VIDEO COMMUNICATIONS of San Jose, Calif., GOOGLE HANGOUTS by ALPHABET INC. of Mountain View, Calif., and SKYPE FOR BUSINESS and TEAMS provided by MICROSOFT CORPORATION, of Redmond, Wash.) to facilitate communication between two or more participants present at separate physical locations. As also discussed briefly above, participants of a communication session in a networked meeting are able to exchange live video, audio, and other types of content to view, hear, and otherwise share information. Participants can also view a common space, e.g., a whiteboard or a shared application, through which ideas can be exchanged. Viewing of the common space can be complemented with a video and audio conference, an instant messaging session, or any combination thereof, such that the networked meeting can act as a near substitute for an in-person meeting. 
     Various types of computing devices can be utilized to participate in networked meetings including, but not limited to, smartphones, tablet computing devices, set-top boxes, smart televisions, video game systems, and even AR, VR, and MR devices. When a participant utilizes an AR device to participate in a networked meeting, the AR device might capture that participant&#39;s view of their surrounding environment and transmit images or video of the view to the other meeting participants. The other meeting participants might then be presented with the images or video of the real-world environment surrounding the user wearing the AR device. The other meeting participants might also be able to view any virtual objects that the AR device has overlaid upon the real-world environment. 
     While meeting participants can view the real-world environment surrounding the user of an AR device, the view is limited to the perspective of the AR device, i.e. the position and orientation of the camera(s) comprising the AR device. As a result, users are constrained to this view when it would often be beneficial to observe the scene from a different perspective or multiple different perspectives. This constraint—each perspective originates from a different camera transmitting a different video stream, can result in inefficient use of computing resources such as, but not limited to, processor cycles, memory, network bandwidth, and power. Moreover, even when multiple cameras transmit multiple video streams of the real-world environment, perspectives between the cameras are elusive. This limited number of perspectives can result in a user spending more time attempting to perform the function of the meeting, e.g. diagnosing a mechanical problem, evaluating a prototype, pricing a piece of artwork, etc. The disclosed HCI addresses the technical considerations set forth above, and potentially others, and thereby provides technical benefits to computing systems implementing the disclosed technologies. 
     Turning now to the figures (which might be referred to herein as a “FIG.” or “FIGS.”), additional details will be provided regarding an improved HCI disclosed herein with reference to the accompanying drawings that form a part hereof. The FIGS. show, by way of illustration, specific configurations or examples. Like numerals represent like or similar elements throughout the FIGS. In the FIGS., the left-most digit(s) of a reference number generally identifies the figure in which the reference number first appears. References made to individual items of a plurality of items can use a reference number with another number included within a parenthetical (and/or a letter without a parenthetical) to refer to each individual item. Generic references to the items might use the specific reference number without the sequence of letters. The drawings are not drawn to scale. 
       FIG.  1    is a computing system diagram illustrating aspects of an operating environment for the embodiments disclosed herein along with aspects of an illustrative HCI that enables a 3D representation of a real-world environment through a video call, according to one embodiment disclosed herein. As shown in  FIG.  1   , a system  100  disclosed herein utilizes a computing device  102  in some embodiments. The computing device  102 , alone or in combination with one or more other devices (e.g. a local computer or one or more remote computing devices  104 ), might form a system  100  that performs or otherwise implements the various processes and techniques described herein. 
     In the configuration shown in FIGS., the computing device  102  takes the form of a wearable, head-mounted display device that is worn by a user. It will be understood, however, that the computing device  102  might take a variety of different forms other than the specific configurations depicted in the FIGS. Although the configurations disclosed herein are discussed primarily in the context of AR devices, it is to be appreciated that the technologies disclosed herein can also be utilized with other types of devices that include functionality for spatial mapping such as, but not limited to, appropriately configured VR devices, MR devices smartphones, and tablet computing devices. 
     The computing device  102  is configured with sensors, other hardware, and program code capable of 3D spatial mapping, such as an AR device or appropriately-configured smartphone, that generates mesh data  106 . The mesh data  106  defines a 3D representation of a real-world environment  109 , including any physical objects such as table  110 , window  114 , and wall  116  in the real-world environment  109 . Examples of mesh data  106  include, but are not limited to, a 3D depth map. The computing device  102  can also capture audio present in the real-world environment  109 , such as speech of the user  119 A. The computing device  102  also generates still or moving images  108  (i.e. a video) of the real-world environment  109 . The terms “image” or “images,” as used herein, encompass both still images and moving images, such as digital video. In some embodiments, images  108  are embedded into mesh data  106 , such that a single stream of combined 3D depth map and image data is provided to remote computing device  104 . 
     The computing device  102  includes one or more display panels (not shown in  FIG.  1   ) that display computer generated (“CG”) graphics. For example, the computing device  102  might include a right-eye display panel for right-eye viewing and a left-eye display panel for left-eye viewing. A right-eye display panel is typically located near a right eye of the user to fully or partially cover a field of view of the right eye, and a left-eye display panel is located near a left eye of the user to fully or partially cover a field of view of the left eye. 
     In another example, a unitary display panel might extend over both the right and left eyes of a user and provide both right-eye and left-eye viewing via right-eye and left-eye viewing regions of the unitary display panel. In each of these implementations, the ability of the computing device  102  to separately display different right-eye and left-eye graphical content via right-eye and left-eye displays might be used to provide a user  119 A of the computing device  102  with a stereoscopic viewing experience. 
     The computing device  102  might include a variety of on-board sensors. For example, and without limitation, a sensor subsystem (not shown in  FIG.  1   ) might include one or more outward facing optical cameras (e.g., cameras located on an external surface of the computing device  102  and forward facing in a viewing direction of the user  119 A). The computing device  102  can also include one or more inward facing optical cameras (also not shown in  FIG.  1   ) (e.g., rearward facing toward the user  119 A and/or toward one or both eyes of the user  119 A). 
     The computing device  102  can also include a variety of other sensors (not shown in  FIG.  1   ) including, but not limited to, accelerometers, gyroscopes, magnetometers, environment understanding cameras, depth cameras (which might be referred to as scene reconstruction or “SR” cameras), inward or outward facing video cameras, microphones, ambient light sensors, and potentially other types of sensors. Data obtained by the sensors can be utilized to detect the location, orientation (which might be referred to as a “pose”), and movement of the computing device  102 . 
     The one or more outward facing optical cameras of the computing device  102  can be configured to observe the real-world environment  109  and output images  108  illustrating the real-world environment  109  observed by a user  119 A of the computing device  102 . The optical cameras are red-green-blue (“RGB”) cameras and infrared cameras in one embodiment. It is to be appreciated, however, that other types of cameras can be utilized in other configurations such as, but not limited to, black and white (“B&amp;W”) cameras. Additionally, and as mentioned above, the same or different cameras can be utilized for tracking motion of the head of the user  119 A (i.e. “head tracking). 
     The computing device  102  captures mesh data  106 , images  108 , and audio data from a perspective  103  of the computing device  102 . As used herein, perspective refers to a point of view. In some embodiments, perspective  103  is determined by the location and orientation of computing device  102 , e.g. when cameras or other sensors used to capture mesh data  106  and images  108  are fixed relative to computing device  102 . As such, perspective  103  may change as user  119 A moves or looks around the real-world environment  109 . In other embodiments, one or more cameras or other sensors used to capture mesh data  106  and images  108  may be oriented independent of computing device  102 , e.g. maintaining a perspective on a particular object even if the location and/or orientation of computing device  102  changes. Perspective, combined with focal length, a far distance clip, a close distance clip, and other attributes, may define a field of view, i.e. a portion of the real-world environment  109  (also referred to as the ‘scene’) that is currently being captured by the cameras and other sensors of computing device  102 . “Field of view” may also be referred to as the “projection” of the real-world environment. 
     The computing device  102  might also include a processing subsystem (not shown in  FIG.  1   ) that includes one or more processor devices that perform at least some of the processes and operations described herein, as defined by instructions executed by the processing subsystem. Such processes or operations might include generating and providing image signals to the display panels, receiving sensory signals from sensors such as cameras, enacting control strategies and procedures responsive to those sensory signals, generating the mesh data  106 , and transmitting the mesh data  106  to one or more remote computing devices  104 . Other computing systems, such as local or remote computing devices  104  might also perform some of the computational tasks disclosed herein. 
     The computing device  102  might also include an on-board data storage subsystem (not shown in  FIG.  1   ) that includes one or more memory devices storing computer-executable instructions (e.g., software and/or firmware) executable by the processing subsystem and might additionally hold other suitable types of data. The computing device  102  might also include a communications subsystem supporting wired and/or wireless communications with remote devices (i.e., off-board devices) over a communications network (not shown in  FIG.  1   ). As an example, the communication subsystem of the computing device  102  might be configured to wirelessly send or receive mesh data  106 , images  108 , digital audio, and/or other information to and from the remote computing device  104 . 
     The computing device  102  can also be utilized to augment a user&#39;s view of the real-world environment  109  with virtual objects, e.g. virtual glass  112 . The virtual objects appear as if they are actually present in the real-world environment  109  when the real-world environment  109  is viewed with the computing device  102 . Additional details regarding the configuration and operation of an illustrative computing device  102  will be provided below with regard to  FIG.  8   . 
     As described briefly above, the computing device  102  interacts with a remote computing device  104  in some embodiments. The remote computing device  104  may be a personal computer, a wearable computer, including a head mounted display (“HMD”), or any other type of computing device having components for causing a display of one or more images on a display, such as the illustrative graphical user interface (“UI”)  118 . 
     The remote computing device  104  executes an application program, or another type of program, that is configured to enable networked meetings, such as those described above. As also described briefly above, networked meetings can provide various types of communications sessions that enable participants, such as the user  119 A wearing computing device  102  and a user  119 B using the remote computing device  104  to share information. Such communications sessions can include, but are not limited to, a broadcast session (i.e. one participant to many), a conference session (i.e. many participants to many participants), or a peer-to-peer session (i.e. one participant to one other participant). 
     The remote computing device  104  also receives the mesh data  106  and images  108  generated by the computing device  102  and renders the images  108  in the UI  118 . In this manner, a user  119 B of the remote computing device can see the view of the real-world environment  109  as seen by the user  119 A of the computing device  102  along with any virtual objects augmenting that view in the UI  118 . It should be appreciated that, although not illustrated in  FIG.  1   , various network devices and connections can be utilized to enable data communications between the computing device  102  and the remote computing device  104 . 
     In some embodiments, UI  118  maintains the perspective  103  of computing device  102 . Although the field of view visible on UI  118  may be limited based on the viewing angle of computing device  102 , the shared perspective may allow users  119 A and  119 B to collaborate based on the shared view of real-world environment  109 . In some embodiments, remote computing device  104  renders the shared perspective by overlaying images  108  over mesh data  106  for display on UI  118 . For example, real world objects such as table  110 , window  114 , and wall  116  may be depicted on UI  118  as table  110 ′, window  114 ′, and wall  116 ′. Similarly, virtual objects, such as glass  112 , which appear to user  119 A when wearing computing device  102 , may also be rendered on UI  118 , e.g. as glass  112 . 
       FIG.  2    is a computing system diagram  200  illustrating a user  119 B viewing a 3D representation  218  of a scene from a second perspective  203  that is other than (i.e. different from) the perspective  103  of the outward facing optical camera of the computing device  102  capturing the scene. While  FIG.  2    depicts a particular second perspective  203 , any other perspective is similarly contemplated, including other rotations, translations (e.g. simulating walking or flying around the real-world environment) or the like. As depicted in 3D representation  218 , table  210 , virtual glass  212 , window  214 , and wall  216  are depicted from the second perspective  203 . In some embodiments this view is reconstructed from mesh data  106  and images  108  by generating the 3D representation, changing the point of view algorithmically, and projecting the updated 3D representation on remote computing device  104 . 
     In some embodiments the user&#39;s device comprises a 2D display, such as an LCD monitor. Projecting the 3D representation onto a 2D display may involve steps such as generating a depth map from the new perspective. The depth map may be generated, for each pixel on the 2D display, by calculating a distance from the new perspective to a portion of the 3D representation associated with the pixel. For example, for each pixel that displays a part of table  210 , a distance from the new perspective to the corresponding part of the table is calculated. In some embodiments, this calculation is based on positions of objects in the scene as encoded by mesh data  106 . For example, table  210  may be comprised of a series of triangles, rectangles, or other geometric shapes, defined in size, orientation, and location. Determining a distance from the new 3D perspective may include determining a distance from the new 3D perspective to one or more of the geometric shapes included in mesh data  106 . 
     In some embodiments, shadows cast by objects in the 3D representation are determined by casting light rays from light sources in the scene and calculating when those light rays strike an object in mesh data  106 . The direction of light rays and the locations of objects they strike may be used to determine how lights cast shadows from the second perspective  203 . In some embodiments, light sources are determined from mesh data  106  and images  108  based on machine learning techniques for identifying light-bulbs, lamps, and other light sources. 
     Next, in some embodiments, color values for each of the pixels are calculated based a color of the pixel derived from images  108 , one or more lighting values (calculated based on light sources and shadows cast by other objects in the scene), and the like. 
     In some embodiments, the 3D representation is rendered using a 3D-enabled device, such as a VR/AR/MR device. In these embodiments, the 3D representation is rendered in 3D, avoiding the process of projecting a 3-dimensional representation onto a 2D display. However, determining shadows and other image processing operations occur as described above. 
     In some embodiments, virtual objects such as virtual glass  212  are included in the rendering process. In some embodiments, as discussed above, light sources may be detected within the scene. In these situations, lighting effects and shadows may be applied to virtual objects such as virtual glass  212 . For example, a light source may be used to calculate a shadow cast by the virtual object. 
     In some embodiments, virtual objects placed in the scene may be rendered to include reflections, shading, or other details incorporated from surrounding objects. For example, a virtual sphere defined as having a reflective surface and placed next to a candle on a table-top may reflect images of the table top and the candle. This reflection may be accomplished using shader techniques, ray tracing, or other algorithms known in the art to estimate the effect that light from surrounding objects would have on virtual objects. Processing reflections on virtual objects may be performed by computing device  102  or remote computing device  104 . 
     Embodiments depicted in  FIG.  2    provide additional insight into the real-world environment in a computationally efficient manner by providing user  119 B with additional viewing angles of the scene. For example, if user  119 A is seeking help from user  119 B positioning table  210  within the scene, user  119 B may use the different perspective to judge how close table  210  should be positioned next to wall  116 . 
       FIG.  3    is a computing system diagram  300  illustrating two computing devices simultaneously displaying two different perspectives of a 3D representation of the scene. In some embodiments, user  119 B is wearing a 3D-enabled device  302 , which may be a VR headset, AR headset, MR headset, or similar device. 3D-enabled device  302  may display UI  318  containing a 3D representation of the scene from perspective  103 . In this way, user  119 B is enabled to view, through computing device  302 , the scene as it is viewed by user  119 A. At the same time, remote computing device  104  displays UI  320 , viewing the scene from a different perspective, e.g. the perspective discussed above in conjunction with  FIG.  2   . 
     In some embodiments, the 3D perspective displayed in UI  318  may track the perspective of user  119 A, e.g. as device  102  moves and/or rotates, the perspective displayed in UI  318  is updated to reflect the new perspective. For example, as user  119 A moves through the scene, looks around, or otherwise changes the position and/or orientation of computing device  102 , UI  318  may be updated to display the perspective from the new position/orientation of device  102 . 
     In some embodiments, device  102  may be moved contiguously through the real-world environment such that the field of view does not change significantly from frame to frame. As such, the mesh data representation of one frame may contain a significant portion of the mesh data used to display a subsequent frame. In these situations, computing device  102  may transmit an update or ‘diff’ of mesh data. 
     In some embodiments, in order to provide a smoother visual experience for user  119 B, device  102  may transmit the change in perspective (i.e. the new position and orientation of device  102 ) apart from the updated mesh data, allowing computing device  302  to use existing mesh data  106  display the new perspective while the updated mesh data is captured and transmitted. This existing mesh data is stale, as it does not incorporate additional information from the new perspective. However, once the additional mesh data information is received, device  302  may update the content of UI  318  accordingly. 
     At any time, user  119 B may decouple the perspective of UI  318  from the perspective  103  of user  119 A. This may be beneficial if user  119 B sees something of interest in the scene or finds a perspective that is enlightening to the task at hand. User  119 B may choose to pause the perspective temporarily, e.g. for a set amount of time, after which the perspective may revert to the real-time perspective of user  119 A. Similarly, user  119 B may choose to decouple from the perspective of user  119 A indefinitely, or until user  119 B makes another decision regarding a choice of perspective. 
     In some embodiments, user  119 B may choose to create a virtual camera from the current perspective (either a paused perspective or a perspective that is tracking perspective  103  of user  119 A). The virtual camera may create a permanent or semi-permanent perspective of the scene. In this way, user  119 B may identify multiple different perspectives that are of value to accomplishing the task at hand. 
     In some embodiments, user  119 A may change the perspective displayed on UI  318 , e.g. rotating between a paused perspective, a live perspective, a virtual camera perspective, or the like. In some embodiments, multiple perspectives may be displayed simultaneously on device  302 , e.g. in a grid pattern. In some embodiments, user  119 B may select one of the perspectives to be displayed on a different device, such as UI  320  of remote computing device  104 . This flexibility in determining new perspectives, selecting from a list of perspectives for display, and selecting the displays/devices on which to view the perspectives greatly enhances the meeting experience, in many cases providing more information to user  119 B than a person physically present in the room with user  119 A. 
     In some embodiments, pausing, decoupling, or otherwise changing the perspective displayed on one or more UIs does not stop the 3D representation of the scene from being rendered. For example, if user  119 A is building a house of cards, user  119 B may pause the perspective displayed in UI  318  while continuing to watch user  119 A build the house of cards. Pausing the perspective causes user  119 B to view the scene from a fixed perspective, even if the perspective of user  119 A continues to change. User  119 B may wish to pause the perspective if user  119 A is making sudden changes to perspective  103  that distract from the content of the scene, among other reasons. 
       FIG.  4    is a computing system diagram  400  illustrating a location of a virtual camera  404  on a floor-map  402  of a 3D representation of the scene. As illustrated, virtual camera  404  is oriented to view table  410 , virtual glass  412 , and window  414 . Virtual camera  404  may be fixed at a location and/or orientation, or virtual camera  404  may be tied to a location and/or orientation of a device such as device  102 . For example, virtual camera  404  may identify the location and/or orientation of device  102  as user  119 A sits on a couch viewing the scene but will be updated accordingly if user  119 A moves device  102 . In other embodiments, virtual camera  404  may represent the perspective of a device used to view a 3D representation of the scene. For example, virtual camera  404  may represent a perspective of device  302 . In some embodiments, the location and/or orientation of virtual camera  404  is set by user  119 B, e.g. as discussed above in conjunction with  FIG.  3   . Additionally or alternatively, the location and/or orientation of virtual camera  404  may be set by user  119 A. 
     In some embodiments, virtual camera  404  may be moved throughout floor-map  402  using a mouse or other pointer input device, e.g. by clicking on virtual camera  404  and dragging it to another position. Keyboard input, or any other type of human computer interface, may also be used to move and/or redirect the orientation of virtual camera  404 . In some embodiments, a perspective generated by virtual camera  404  may be displayed by a UI. In these embodiments, as the location and/or orientation of virtual camera  404  is changed, the associated perspective of the 3D representation is updated. For example, if computing device  302  is associated with virtual camera  404 , changing the location and/or orientation of virtual camera  404  may change the perspective displayed in UI  318 . Conversely, if user  119 B moves computing device  302 , changing the perspective of the 3D representation displayed by computing device  302 , virtual camera  404  may be moved accordingly on floor-map  402  to reflect the new perspective. 
     In some embodiments, virtual camera  404  may be assigned to track a target object in the scene, such as a person, an object identified as needing repair, or the like. Once the target object is selected by a user (e.g. user  119 A or  119 B), a 3D model of the target object may be extracted from mesh data  106 . Then, if the target object is moved in the real-world scene, e.g. if user  119 A picks it up and sets it down in a new location, one of computing devices  102 ,  104 , or  302  may search the scene to locate the 3D model of the target object in the new location. Once the new location of the target object has been identified, virtual camera  404  may automatically change perspective to keep the target object in view. 
     Floor-map  402  may comprise a top-down view of the scene (as illustrated), an isometric view of the scene, or the like. Floor-map  402  may, in some embodiments, be generated using the same mesh data  106  and/or images  108  used to generate a 3D representation of the scene. A floor-map may be useful by providing context to user  119 B, who may not otherwise realize the extent of the scene. 
       FIG.  5    is a computing system diagram  500  illustrating a 3D representation of the scene that has been integrated with data captured in the past. In some embodiments, couch  502  and lamp  504  were captured in the past, generating past mesh data  506  and past images  508 . Past captures may have been performed by device  102 , or by another device (not pictured). In some embodiments, past captures may have been performed during the course of the meeting, e.g. when user  119 A was directing computing device  102  towards couch  502  and lamp  504 . By saving the information captured about these objects (mesh data and images) and integrating this data with the real-time stream of mesh data and images, a more complete scene may be available to user  119 B than the real-time data alone can provide. 
     Data captured in the past may also be used to provide additional details of objects currently in view of the live stream. For example, table  410  may be captured from the perspective of computing device  102 , but real-time data is not available for parts of table  410  that are occluded. As such, without integrating data captured in the past, user  119 B would not be able to view the occluded portions of table  410 . 
     In some embodiments, computing device  102  may identify a room or other environment it is in based on mesh data. For example, computing device  102  may infer the size of the room based on the location and size of walls, the location and size of windows, and the location and size of other objects that do not tend to move. Once the room has been identified, mesh data and images previously captured from within the room may be integrated in the real-time 3D representation. Other environments besides rooms, indoor and outdoor, are similarly contemplated. 
       FIG.  6    is a computing system diagram  600  illustrating a 3D representation of the scene that has been integrated with data captured by a second camera  610 . In some embodiments, second camera  610  has been added to the computing environment. Second camera  610  may comprise a depth finding camera (also described herein as a scene reconstruction or ‘SR’ camera) in addition to an RGB optical camera. Second camera  610  may generate additional mesh data, adding to mesh data  106  captured in real-time and/or mesh data previously captured. 
     In some embodiments, UI  618  depicts a floor-plan view of the scene, integrating data from computing device  102  and second camera  610 . As such, couch  602  and lamp  604  are rendered based on real-time data. Similarly, some portions of table  410  that would be occluded if second camera  610  was not present, are visible. 
     In some embodiments, virtual camera  404  depicts the location and orientation of a virtual camera associated with computing device  302 . The perspective of virtual camera  404  is rendered in UI  620 . Similarly, the perspective of virtual camera  612  is rendered in UI  622 . In one embodiment, user  119 B is enabled to switch between the perspectives of UI  620  and UI  622 . 
     In one embodiment, second camera  610  is included in UIs  620  and  622 , as second camera  610  is a real-world object included in the scene. However, in other embodiments, computing device  102  may not render other cameras in the scene. In some embodiments, computing device  102  may know the location of other cameras in the scene. Mesh data and images captured from a time when the other camera was not present may be substituted for the mesh data and images of the other camera devices. 
       FIG.  7    is a computing system diagram illustrating aspects of a routine for rendering different perspectives of a 3D environment. It should be understood by those of ordinary skill in the art that the operations of the methods disclosed herein are not necessarily presented in any particular order and that performance of some or all of the operations in an alternative order(s) is possible and is contemplated. The operations have been presented in the demonstrated order for ease of description and illustration. Operations may be added, omitted, performed together, and/or performed simultaneously, without departing from the scope of the appended claims. 
     It should also be understood that the illustrated methods can end at any time and need not be performed in their entireties. Some or all operations of the methods, and/or substantially equivalent operations, can be performed by execution of computer-readable instructions included on a computer-storage media, as defined herein. The term “computer-readable instructions,” and variants thereof, as used in the description and claims, is used expansively herein to include routines, applications, application modules, program modules, programs, components, data structures, algorithms, and the like. Computer-readable instructions can be implemented on various system configurations, including single-processor or multiprocessor systems, minicomputers, mainframe computers, personal computers, hand-held computing devices, microprocessor-based, programmable consumer electronics, combinations thereof, and the like. 
     Thus, it should be appreciated that the logical operations described herein are implemented (1) as a sequence of computer implemented acts or program modules running on a computing system such as those described herein) and/or (2) as interconnected machine logic circuits or circuit modules within the computing system. The implementation is a matter of choice dependent on the performance and other requirements of the computing system. Accordingly, the logical operations may be implemented in software, in firmware, in special purpose digital logic, and any combination thereof. 
     Additionally, the operations illustrated in  FIG.  7    and the other FIGS. can be implemented in association with the example computing devices and UIs described above with respect to  FIGS.  1  through  6   . For instance, the various device(s) and/or module(s) described herein can generate, transmit, receive, and/or display data associated with content of a communication session (e.g., live content, recorded content, etc.) and/or a 3D representation that includes images  108  of one or more participants (e.g. the user  119 A or a user  119 B of the remote computing device  104 ), avatars, channels, chat sessions, video streams, images, virtual objects, and/or applications associated with a communication session. 
     The routine  700  begins at operation  702 , where the remote computing device  104  receives mesh data  106  that defines a 3D representation of a real-world environment  109  from the computing device  102 . In some embodiments, the mesh data has been captured by device  102  from a perspective  103  of device  102 . The routine then proceeds to operation  704 , where the remote computing device  104  receives images  108  of the real-world environment  109  from the computing device  102 , also from perspective  103 . The routine  700  then proceeds from operation  704  to operation  706 . 
     At operation  706 , the remote computing device  104  determines a second perspective, in one embodiment, based on a position and orientation of a virtual camera. In some embodiments, the perspective is different from perspective  103  of computing device  102 . As discussed above, the second perspective may be based on a position and orientation of a computing device  302  worn by user  119 B, a fixed perspective, a perspective tied to an object selected from the scene, or the like. 
     The routine  700  then proceeds to operation  708 , where the remote computing device  104  receives previously captured mesh data and images of the real-world environment. As discussed above in conjunction with  FIGS.  5  and  6   , previously captured mesh data and images may have been captured by computing device  102  at an earlier point in the meeting, even minutes or seconds before the present moment. For example, as user  119 A scans the room, or walks around the room, mesh data and images may be captured for different parts of the room. Additionally or alternatively, previously captured mesh data and images may have been captured by a different computing device, e.g. second camera  610 . 
     The routine  700  then proceeds to operation  710 , where the previously captured mesh data and images are integrated into the real-time 3D representation of the real-world environment. In some embodiments, integration of previously captured mesh data adds objects, or perspectives of objects, to the 3D environment that are not visible from the real-time mesh data and images captured by computing device  102 . 
     Once the previously captured mesh data and images have been integrated into the received mesh data and images, the routine  700  proceeds to operation  712 , where the remote computing device  104  renders the 3D representation from the second perspective. From operation  712  the routine  700  proceeds to operation  714 , where it ends. 
     It should be appreciated that the above-described subject matter may be implemented as a computer-controlled apparatus, a computer process, a computing system, or as an article of manufacture such as a computer-readable storage medium. The operations of the example methods are illustrated in individual blocks and summarized with reference to those blocks. The methods are illustrated as logical flows of blocks, each block of which can represent one or more operations that can be implemented in hardware, software, or a combination thereof. In the context of software, the operations represent computer-executable instructions stored on one or more computer-readable media that, when executed by one or more processors, enable the one or more processors to perform the recited operations. 
     Generally, computer-executable instructions include routines, programs, objects, modules, components, data structures, and the like that perform particular functions or implement particular abstract data types. The order in which the operations are described is not intended to be construed as a limitation, and any number of the described operations can be executed in any order, combined in any order, subdivided into multiple sub-operations, and/or executed in parallel to implement the described processes. The described processes can be performed by resources associated with one or more device(s) such as one or more internal or external CPUs or GPUs, and/or one or more pieces of hardware logic such as field-programmable gate arrays (“FPGAs”), digital signal processors (“DSPs”), or other types of accelerators. 
     All of the methods and processes described above may be embodied in, and fully automated via, software code modules executed by one or more general purpose computers or processors. The code modules may be stored in any type of computer-readable storage medium or other computer storage device, such as those described below. Some or all of the methods may alternatively be embodied in specialized computer hardware, such as that described below. 
     Any routine descriptions, elements or blocks in the flow diagrams described herein and/or depicted in the attached figures should be understood as potentially representing modules, segments, or portions of code that include one or more executable instructions for implementing specific logical functions or elements in the routine. Alternate implementations are included within the scope of the examples described herein in which elements or functions may be deleted, or executed out of order from that shown or discussed, including substantially synchronously or in reverse order, depending on the functionality involved as would be understood by those skilled in the art. 
       FIG.  8    is a diagram illustrating an example environment  800  in which a system  802  can operate to populate the HCI disclosed herein with images  108 , virtual objects  112 , and/or other types of presentation content. In some implementations, a system implemented agent may function to collect and/or analyze data associated with the example environment  800 . For example, the agent may function to collect and/or analyze data exchanged between participants involved in a communication session  804  linked to the GUIs disclosed herein. 
     As illustrated, the communication session  804  may be implemented between a number of client computing devices  806 ( 1 ) through  806 (N) (where N is a positive integer number having a value of two or greater) that are associated with the system  802  or are part of the system  802 . The client computing devices  806 ( 1 ) through  806 (N) enable users, also referred to as individuals, to participate in the communication session  804 . For instance, the first client computing device  806 ( 1 ) may be the remote computing device  104  of  FIG.  1    and the second client computing device  806 ( 2 ) may be the computing device  102  of  FIG.  1   , and AR device  1000  of  FIG.  10   . 
     In this example, the communication session  804  is hosted, over one or more network(s)  808 , by the system  802 . That is, the system  802  can provide a service that enables users of the client computing devices  806 ( 1 ) through  806 (N) to participate in the communication session  804  (e.g., via a live viewing and/or a recorded viewing). Consequently, a “participant” to the communication session  804  can comprise a user and/or a client computing device (e.g., multiple users may be in a communication room participating in a communication session via the use of a single client computing device), each of which can communicate with other participants. As an alternative, the communication session  804  can be hosted by one of the client computing devices  806 ( 1 ) through  806 (N) utilizing peer-to-peer technologies. The system  802  can also host chat conversations and other team collaboration functionality (e.g., as part of an application suite). 
     In some implementations, such chat conversations and other team collaboration functionality are considered external communication sessions distinct from the communication session  804 . A computerized agent to collect participant data in the communication session  804  may be able to link to such external communication sessions. Therefore, the computerized agent may receive information, such as date, time, session particulars, and the like, that enables connectivity to such external communication sessions. In one example, a chat conversation can be conducted in accordance with the communication session  804 . Additionally, the system  802  may host the communication session  804 , which includes at least a plurality of participants co-located at a meeting location, such as a meeting room or auditorium, or located in disparate locations. 
     In examples described herein client computing devices  806 ( 1 ) through  806 (N) participating in the communication session  804  are configured to receive and render for display, on a user interface of a display screen, communication data. The communication data can comprise a collection of various instances, or streams, of live content and/or recorded content. The collection of various instances, or streams, of live content and/or recorded content may be provided by one or more cameras, such as video cameras. For example, an individual stream of live or recorded content can comprise media data associated with a video feed provided by a video camera (e.g., audio and visual data that capture the appearance and speech of a user participating in the communication session). In some implementations, the video feeds may comprise such audio and visual data, one or more still images, and/or one or more avatars. The one or more still images may also comprise one or more avatars. 
     Another example of an individual stream of live or recorded content can comprise media data that includes an avatar of a user participating in the communication session along with audio data that captures the speech of the user. Yet another example of an individual stream of live or recorded content can comprise media data that includes a file displayed on a display screen along with audio data that captures the speech of a user. Accordingly, the various streams of live or recorded content within the communication data enable a remote meeting to be facilitated between a group of people and the sharing of content within the group of people. In some implementations, the various streams of live or recorded content within the communication data may originate from a plurality of co-located video cameras, positioned in a space, such as a room, to record or stream live a presentation that includes one or more individuals presenting and one or more individuals consuming presented content. 
     A participant or attendee can view content of the communication session  804  live as activity occurs, or alternatively, via a recording at a later time after the activity occurs. In examples described herein client computing devices  806 ( 1 ) through  806 (N) participating in the communication session  804  are configured to receive and render for display, on a user interface of a display screen, communication data. The communication data can comprise a collection of various instances, or streams, of live and/or recorded content. For example, an individual stream of content can comprise media data associated with a video feed (e.g., audio and visual data that capture the appearance and speech of a user participating in the communication session). Another example of an individual stream of content can comprise media data that includes an avatar of a user participating in the conference session along with audio data that captures the speech of the user. Yet another example of an individual stream of content can comprise media data that includes a content item displayed on a display screen and/or audio data that captures the speech of a user. Accordingly, the various streams of content within the communication data enable a meeting or a broadcast presentation to be facilitated amongst a group of people dispersed across remote locations. 
     A participant or attendee to a communication session is a person that is in range of a camera, or other image and/or audio capture device such that actions and/or sounds of the person which are produced while the person is viewing and/or listening to the content being shared via the communication session can be captured (e.g., recorded). For instance, a participant may be sitting in a crowd viewing the shared content live at a broadcast location where a stage presentation occurs. Or a participant may be sitting in an office conference room viewing the shared content of a communication session with other colleagues via a display screen. Even further, a participant may be sitting or standing in front of a personal device (e.g., tablet, smartphone, computer, etc.) viewing the shared content of a communication session alone in their office or at home. 
     The system  802  includes device(s)  810 . The device(s)  810  and/or other components of the system  802  can include distributed computing resources that communicate with one another and/or with the client computing devices  806 ( 1 ) through  806 (N) via the one or more network(s)  808 . In some examples, the system  802  may be an independent system that is tasked with managing aspects of one or more communication sessions such as communication session  804 . As an example, the system  802  may be managed by entities such as SLACK, WEBEX, GOTOMEETING, GOOGLE HANGOUTS, etc. 
     Network(s)  808  may include, for example, public networks such as the Internet, private networks such as an institutional and/or personal intranet, or some combination of private and public networks. Network(s)  808  may also include any type of wired and/or wireless network, including but not limited to local area networks (“LANs”), wide area networks (“WANs”), satellite networks, cable networks, Wi-Fi networks, WiMax networks, mobile communications networks (e.g., 3G, 4G, and so forth) or any combination thereof. Network(s)  808  may utilize communications protocols, including packet-based and/or datagram-based protocols such as Internet protocol (“IP”), transmission control protocol (“TCP”), user datagram protocol (“UDP”), or other types of protocols. Moreover, network(s)  808  may also include a number of devices that facilitate network communications and/or form a hardware basis for the networks, such as switches, routers, gateways, access points, firewalls, base stations, repeaters, backbone devices, and the like. 
     In some examples, network(s)  808  may further include devices that enable connection to a wireless network, such as a wireless access point (“WAP”). Examples support connectivity through WAPs that send and receive data over various electromagnetic frequencies (e.g., radio frequencies), including WAPs that support Institute of Electrical and Electronics Engineers (“IEEE”) 802.11 standards (e.g., 802.11g, 802.11n, 802.11ac and so forth), and other standards. 
     In various examples, device(s)  810  may include one or more computing devices that operate in a cluster or other grouped configuration to share resources, balance load, increase performance, provide fail-over support or redundancy, or for other purposes. For instance, device(s)  810  may belong to a variety of classes of devices such as traditional server-type devices, desktop computer-type devices, and/or mobile-type devices. Thus, although illustrated as a single type of device or a server-type device, device(s)  810  may include a diverse variety of device types and are not limited to a particular type of device. Device(s)  810  may represent, but are not limited to, server computers, desktop computers, web-server computers, personal computers, mobile computers, laptop computers, tablet computers, or any other sort of computing device. 
     A client computing device (e.g., one of client computing device(s)  806 ( 1 ) through  806 (N)) may belong to a variety of classes of devices, which may be the same as, or different from, device(s)  810 , such as traditional client-type devices, desktop computer-type devices, mobile-type devices, special purpose-type devices, embedded-type devices, and/or wearable-type devices. Thus, a client computing device can include, but is not limited to, a desktop computer, a game console and/or a gaming device, a tablet computer, a personal data assistant (“PDA”), a mobile phone/tablet hybrid, a laptop computer, a telecommunication device, a computer navigation type client computing device such as a satellite-based navigation system including a global positioning system (“GPS”) device, a wearable device, a virtual reality (“VR”) device, an augmented reality (“AR”) device, an implanted computing device, an automotive computer, a network-enabled television, a thin client, a terminal, an Internet of Things (“IoT”) device, a work station, a media player, a personal video recorder (“PVR”), a set-top box, a camera, an integrated component (e.g., a peripheral device) for inclusion in a computing device, an appliance, or any other sort of computing device. Moreover, the client computing device may include a combination of the earlier listed examples of the client computing device such as, for example, desktop computer-type devices or a mobile-type device in combination with a wearable device, etc. 
     Client computing device(s)  806 ( 1 ) through  806 (N) of the various classes and device types can represent any type of computing device having one or more data processing unit(s)  892  operably connected to computer-readable media  894  such as via a bus  816 , which in some instances can include one or more of a system bus, a data bus, an address bus, a PCI bus, a Mini-PCI bus, and any variety of local, peripheral, and/or independent buses. 
     Executable instructions stored on computer-readable media  894  may include, for example, an operating system  819 , a client module  820 , a profile module  822 , and other modules, programs, or applications that are loadable and executable by data processing units(s)  892 . 
     Client computing device(s)  806 ( 1 ) through  806 (N) may also include one or more interface(s)  824  to enable communications between client computing device(s)  806 ( 1 ) through  806 (N) and other networked devices, such as device(s)  810 , over network(s)  808 . Such network interface(s)  824  may include one or more network interface controllers (NICs) or other types of transceiver devices to send and receive communications and/or data over a network. Moreover, client computing device(s)  806 ( 1 ) through  806 (N) can include input/output (“I/O”) interfaces  824  that enable communications with input/output devices  826  such as user input devices including peripheral input devices (e.g., a game controller, a keyboard, a mouse, a pen, a voice input device such as a microphone, a video camera for obtaining and providing video feeds and/or still images, a touch input device, a gestural input device, and the like) and/or output devices including peripheral output devices (e.g., a display, a printer, audio speakers, a haptic output device, and the like).  FIG.  8    illustrates that client computing device  806 ( 1 ) is in some way connected to a display device (e.g., a display screen  828 ( 1 )), which can display a GUI according to the techniques described herein. 
     In the example environment  800  of  FIG.  8   , client computing devices  806 ( 1 ) through  806 (N) may use their respective client modules  820  to connect with one another and/or other external device(s) in order to participate in the communication session  804 , or in order to contribute activity to a collaboration environment. For instance, a first user may utilize a client computing device  806 ( 1 ) to communicate with a second user of another client computing device  806 ( 2 ). When executing client modules  820 , the users may share data, which may cause the client computing device  806 ( 1 ) to connect to the system  802  and/or the other client computing devices  806 ( 2 ) through  806 (N) over the network(s)  808 . 
     The client computing device(s)  806 ( 1 ) through  806 (N) may use their respective profile module  822  to generate participant profiles (not shown in  FIG.  8   ) and provide the participant profiles to other client computing devices and/or to the device(s)  810  of the system  802 . A participant profile may include one or more of an identity of a user or a group of users (e.g., a name, a unique identifier (“ID”), etc.), user data such as personal data, machine data such as location (e.g., an IP address, a room in a building, etc.) and technical capabilities, etc. Participant profiles may be utilized to register participants for communication sessions. 
     As shown in  FIG.  8   , the device(s)  810  of the system  802  includes a server module  830  and an output module  832 . In this example, the server module  830  is configured to receive, from individual client computing devices such as client computing devices  806 ( 1 ) through  806 (N), media streams  834 ( 1 ) through  834 (N). As described above, media streams can comprise a video feed (e.g., audio and visual data associated with a user), audio data which is to be output with a presentation of an avatar of a user (e.g., an audio only experience in which video data of the user is not transmitted), text data (e.g., text messages), file data and/or screen sharing data (e.g., a document, a slide deck, an image, a video displayed on a display screen  828 , etc.), and so forth. Thus, the server module  830  is configured to receive a collection of various media streams  834 ( 1 ) through  834 (N) during a live viewing of the communication session  804  (the collection being referred to herein as “media data  834 ”). In some scenarios, not all the client computing devices that participate in the communication session  804  provide a media stream. For example, a client computing device may only be a consuming, or a “listening”, device such that it only receives content associated with the communication session  804  but does not provide any content to the communication session  804 . 
     In various examples, the server module  830  can select aspects of the media streams  834  that are to be shared with individual ones of the participating client computing devices  806 ( 1 ) through  806 (N). Consequently, the server module  830  may be configured to generate session data  836  based on the streams  834  and/or pass the session data  836  to the output module  832 . Then, the output module  832  may communicate communication data  838  to the client computing devices (e.g., client computing devices  806 ( 1 ) through  806 ( 3 ) participating in a live viewing of the communication session). The communication data  838  may include video, audio, and/or other content data, provided by the output module  832  based on content  850  associated with the output module  832  and based on received session data  836 . 
     As shown, the output module  832  transmits communication data  838 ( 1 ) to client computing device  806 ( 1 ), and transmits communication data  838 ( 2 ) to client computing device  806 ( 2 ), and transmits communication data  838 ( 3 ) to client computing device  806 ( 3 ), etc. The communication data  838  transmitted to the client computing devices can be the same or can be different (e.g., positioning of streams of content within a user interface may vary from one device to the next). 
     In various implementations, the device(s)  810  and/or the client module  820  can include GUI presentation module  840 . The GUI presentation module  840  may be configured to analyze communication data  838  that is for delivery to one or more of the client computing devices  806 . Specifically, the GUI presentation module  840 , at the device(s)  810  and/or the client computing device  806 , may analyze communication data  838  to determine an appropriate manner for displaying video, image, and/or content on the display screen  828  of an associated client computing device  806 . In some implementations, the GUI presentation module  840  may provide video, image, and/or content to a presentation GUI  846  rendered on the display screen  828  of the associated client computing device  806 . The presentation GUI  846  may be caused to be rendered on the display screen  828  by the GUI presentation module  840 . The presentation GUI  846  may include the video, image, and/or content analyzed by the GUI presentation module  840 . 
     In some implementations, the presentation GUI  846  may include a plurality of sections or grids that may render or comprise video, image, and/or content for display on the display screen  828 . For example, a first section of the presentation GUI  846  may include a video feed of a presenter or individual, a second section of the presentation GUI  846  may include a video feed of an individual consuming meeting information provided by the presenter or individual. The GUI presentation module  840  may populate the first and second sections of the presentation GUI  846  in a manner that properly imitates an environment experience that the presenter and the individual may be sharing. 
     In some implementations, the GUI presentation module  840  may enlarge or provide a zoomed view of the individual represented by the video feed in order to highlight a reaction, such as a facial feature, the individual had to the presenter. In some implementations, the presentation GUI  846  may include a video feed of a plurality of participants associated with a meeting, such as a general communication session. In other implementations, the presentation GUI  846  may be associated with a channel, such as a chat channel, enterprise teams channel, or the like. Therefore, the presentation GUI  846  may be associated with an external communication session that is different than the general communication session. 
       FIG.  9    illustrates a diagram that shows example components of an example device  900  configured to populate the HCI disclosed herein that may include one or more sections or grids that may render or comprise video, image, virtual objects  116 , and/or content for display on the display screen  828 . The device  900  may represent one of device(s)  102  or  104 . Additionally, or alternatively, the device  900  may represent one of the client computing devices  806 . 
     As illustrated, the device  900  includes one or more data processing unit(s)  902 , computer-readable media  904 , and communication interface(s)  906 . The components of the device  900  are operatively connected, for example, via a bus, which may include one or more of a system bus, a data bus, an address bus, a PCI bus, a Mini-PCI bus, and any variety of local, peripheral, and/or independent buses. 
     As utilized herein, data processing unit(s), such as the data processing unit(s)  902  and/or data processing unit(s)  892 , may represent, for example, a CPU-type data processing unit, a GPU-type data processing unit, a field-programmable gate array (“FPGA”), another class of DSP, or other hardware logic components that may, in some instances, be driven by a CPU. For example, and without limitation, illustrative types of hardware logic components that may be utilized include Application-Specific Integrated Circuits (“ASICs”), Application-Specific Standard Products (“ASSPs”), System-on-a-Chip Systems (“SOCs”), Complex Programmable Logic Devices (“CPLDs”), etc. 
     As utilized herein, computer-readable media, such as computer-readable media  904  and computer-readable media  894 , may store instructions executable by the data processing unit(s). The computer-readable media may also store instructions executable by external data processing units such as by an external CPU, an external GPU, and/or executable by an external accelerator, such as an FPGA type accelerator, a DSP type accelerator, or any other internal or external accelerator. In various examples, at least one CPU, GPU, and/or accelerator is incorporated in a computing device, while in some examples one or more of a CPU, GPU, and/or accelerator is external to a computing device. 
     Computer-readable media, which might also be referred to herein as a computer-readable medium, may include computer storage media and/or communication media. Computer storage media may include one or more of volatile memory, nonvolatile memory, and/or other persistent and/or auxiliary computer storage media, removable and non-removable computer storage media implemented in any method or technology for storage of information such as computer-readable instructions, data structures, program modules, or other data. Thus, computer storage media includes tangible and/or physical forms of media included in a device and/or hardware component that is part of a device or external to a device, including but not limited to random-access memory (“RAM”), static random-access memory (“SRAM”), dynamic random-access memory (“DRAM”), phase change memory (“PCM”), read-only memory (“ROM”), erasable programmable read-only memory (“EPROM”), electrically erasable programmable read-only memory (“EEPROM”), flash memory, compact disc read-only memory (“CD-ROM”), digital versatile disks (“DVDs”), optical cards or other optical storage media, magnetic cassettes, magnetic tape, magnetic disk storage, magnetic cards or other magnetic storage devices or media, solid-state memory devices, storage arrays, network attached storage, storage area networks, hosted computer storage or any other storage memory, storage device, and/or storage medium that can be used to store and maintain information for access by a computing device. 
     In contrast to computer storage media, communication media may embody computer-readable instructions, data structures, program modules, or other data in a modulated data signal, such as a carrier wave, or other transmission mechanism. As defined herein, computer storage media does not include communication media. That is, computer storage media does not include communications media consisting solely of a modulated data signal, a carrier wave, or a propagated signal, per se. 
     Communication interface(s)  906  may represent, for example, network interface controllers (“NICs”) or other types of transceiver devices to send and receive communications over a network. Furthermore, the communication interface(s)  906  may include one or more video cameras and/or audio devices  922  to enable generation of video feeds and/or still images, and so forth. 
     In the illustrated example, computer-readable media  904  includes a data store  908 . In some examples, data store  908  includes data storage such as a database, data warehouse, or other type of structured or unstructured data storage. In some examples, data store  908  includes a corpus and/or a relational database with one or more tables, indices, stored procedures, and so forth to enable data access including one or more of hypertext markup language (“HTML”) tables, resource description framework (“RDF”) tables, web ontology language (“OWL”) tables, and/or extensible markup language (“XML”) tables, for example. 
     The data store  908  may store data for the operations of processes, applications, components, and/or modules stored in computer-readable media  904  and/or executed by data processing unit(s)  902  and/or accelerator(s). For instance, in some examples, data store  908  may store session data  910  (e.g., session data  836 ), profile data  912  (e.g., associated with a participant profile), and/or other data. The session data  910  can include a total number of participants (e.g., users and/or client computing devices) in a communication session, activity that occurs in the communication session, a list of invitees to the communication session, and/or other data related to when and how the communication session is conducted or hosted. The data store  908  may also include content data  914 , such as the content  850  that includes video, audio, or other content for rendering and display on one or more of the display screens  828 . 
     Alternately, some or all of the above-referenced data can be stored on separate memories  916  on board one or more data processing unit(s)  902  such as a memory on board a CPU-type processor, a GPU-type processor, an FPGA-type accelerator, a DSP-type accelerator, and/or another accelerator. In this example, the computer-readable media  904  also includes operating system  918  and application programming interface(s)  920  (APIs) configured to expose the functionality and the data of the device  900  to other devices. Additionally, the computer-readable media  904  includes one or more modules such as the server module  930 , the output module  932 , and the GUI presentation module  940 , although the number of illustrated modules is just an example, and the number may vary higher or lower. That is, functionality described herein in association with the illustrated modules may be performed by a fewer number of modules or a larger number of modules on one device or spread across multiple devices. 
       FIG.  10    is a computing device diagram showing aspects of the configuration and operation of an AR device  1000  that can implement aspects of the systems disclosed herein. The AR device  1000  shows details of the computing device  102  shown in  FIG.  1   . As described briefly above, AR devices superimpose CG images over a user&#39;s view of a real-world environment  109 . For example, an AR device  1000  such as that shown in  FIG.  10    might generate composite views to enable a user to visually perceive a CG image superimposed over a real-world environment  109 . As also described above, the technologies disclosed herein can be utilized with AR devices such as that shown in  FIG.  10   , VR devices, MR devices, and other types of devices that utilize depth sensing. 
     In the example shown in  FIG.  10   , an optical system  1002  includes an illumination engine  1004  to generate electromagnetic (“EM”) radiation that includes both a first bandwidth for generating CG images and a second bandwidth for tracking physical objects. The first bandwidth may include some or all of the visible-light portion of the EM spectrum whereas the second bandwidth may include any portion of the EM spectrum that is suitable to deploy a desired tracking protocol. In this example, the optical system  1002  further includes an optical assembly  1006  that is positioned to receive the EM radiation from the illumination engine  1004  and to direct the EM radiation (or individual bandwidths thereof) along one or more predetermined optical paths. 
     For example, the illumination engine  1004  may emit the EM radiation into the optical assembly  1006  along a common optical path that is shared by both the first bandwidth and the second bandwidth. The optical assembly  1006  may also include one or more optical components that are configured to separate the first bandwidth from the second bandwidth (e.g., by causing the first and second bandwidths to propagate along different image-generation and object-tracking optical paths, respectively). 
     In some instances, a user experience is dependent on the AR device  1000  accurately identifying characteristics of a physical object such as the table  110  or plane (such as the real-world floor) and then generating the CG image in accordance with these identified characteristics. For example, suppose that the AR device  1000  is programmed to generate a user perception that a virtual gaming character is running towards and ultimately jumping over a real-world structure. To achieve this user perception, the AR device  1000  might obtain detailed data defining features of the real-world environment  109  around the AR device  1000 . In order to provide this functionality, the optical system  1002  of the AR device  1000  might include a laser line projector and a differential imaging camera in some embodiments. 
     In some examples, the AR device  1000  utilizes an optical system  1002  to generate a composite view (e.g., from a perspective of a user that is wearing the AR device  1000 ) that includes both one or more CG images and a view of at least a portion of the real-world environment  109 . For example, the optical system  1002  might utilize various technologies such as, for example, AR technologies to generate composite views that include CG images superimposed over a real-world view. As such, the optical system  1002  might be configured to generate CG images via an optical assembly  1006  that includes a display panel  1014 . 
     In the illustrated example, the display panel includes separate right eye and left eye transparent display panels, labeled  1014 R and  1014 L, respectively. In some examples, the display panel  1014  includes a single transparent display panel that is viewable with both eyes or a single transparent display panel that is viewable by a single eye only. Therefore, it can be appreciated that the techniques described herein might be deployed within a single-eye device (e.g. the GOOGLE GLASS AR device) and within a dual-eye device (e.g. the MICROSOFT HOLOLENS AR device). 
     Light received from the real-world environment  112  passes through the see-through display panel  1014  to the eye or eyes of the user. Graphical content computed by an image-generation engine  1026  executing on the processing units  1020  and displayed by right-eye and left-eye display panels, if configured as see-through display panels, might be used to visually augment or otherwise modify the real-world environment  109  viewed by the user through the see-through display panels  1014 . In this configuration, the user is able to view virtual objects that do not exist within the real-world environment  109  at the same time that the user views physical objects such as the table  110  within the real-world environment  109 . This creates an illusion or appearance that the virtual objects are physical objects like the table  110  or physically present light-based effects located within the real-world environment  109 . 
     In some examples, the display panel  1014  is a waveguide display that includes one or more diffractive optical elements (“DOEs”) for in-coupling incident light into the waveguide, expanding the incident light in one or more directions for exit pupil expansion, and/or out-coupling the incident light out of the waveguide (e.g., toward a user&#39;s eye). In some examples, the AR device  1000  further includes an additional see-through optical component, shown in  FIG.  10    in the form of a transparent veil  1016  positioned between the real-world environment  109  and the display panel  1014 . It can be appreciated that the transparent veil  1016  might be included in the AR device  1000  for purely aesthetic and/or protective purposes. 
     The AR device  1000  might further include various other components (not all of which are shown in  FIG.  10   ), for example, front-facing cameras (e.g. red/green/blue (“RGB”), black &amp; white (“B&amp;W”), or infrared (“IR”) cameras), speakers, microphones, accelerometers, gyroscopes, magnetometers, temperature sensors, touch sensors, biometric sensors, other image sensors, energy-storage components (e.g. battery), a communication facility, a global positioning system (“GPS”) a receiver, a laser line projector, a differential imaging camera, and, potentially, other types of sensors. Data obtained from one or more sensors  1008 , some of which are identified above, can be utilized to determine the orientation, location, and movement of the AR device  1000 . As discussed above, data obtained from a differential imaging camera and a laser line projector, or other types of sensors, can also be utilized to generate a 3D depth map of the surrounding real-world environment  109 . 
     In the illustrated example, the AR device  1000  includes one or more logic devices and one or more computer memory devices storing instructions executable by the logic device(s) to implement the functionality disclosed herein. In particular, a controller  1018  can include one or more processing units  1020 , one or more computer-readable media  1022  for storing an operating system  1024 , other programs (such as a 3D depth map generation module configured to generate the mesh data  106 ) in the manner disclosed herein), and data. 
     In some implementations, the AR device  1000  is configured to analyze data obtained by the sensors  1008  to perform feature-based tracking of an orientation of the AR device  1000 . For example, in a scenario in which the object data includes an indication of a stationary physical object  110  within the real-world environment  109  (e.g., the table  110 ), the AR device  1000  might monitor a position of the stationary object within a terrain-mapping field-of-view (“FOV”). Then, based on changes in the position of the stationary object within the terrain-mapping FOV and a depth of the stationary object from the AR device  1000 , a terrain-mapping engine  1028  executing on the processing units  1020  AR might calculate changes in the orientation of the AR device  1000 . 
     It can be appreciated that these feature-based tracking techniques might be used to monitor changes in the orientation of the AR device  1000  for the purpose of monitoring an orientation of a user&#39;s head (e.g., under the presumption that the AR device  1000  is being properly worn by a user  118 A). The computed orientation of the AR device  1000  can be utilized in various ways, some of which have been described above. 
     The processing unit(s)  1020 , can represent, for example, a central processing unit (“CPU”)-type processor, a graphics processing unit (“GPU”)-type processing unit, an FPGA, one or more digital signal processors (“DSPs”), or other hardware logic components that might, in some instances, be driven by a CPU. For example, and without limitation, illustrative types of hardware logic components that can be used include ASICs, Application-Specific Standard Products (“ASSPs”), System-on-a-Chip Systems (“SOCs”), Complex Programmable Logic Devices (“CPLDs”), etc. The controller  1018  can also include one or more computer-readable media  1022 , such as the computer-readable media described above. The processing unit(s)  1020  and the computer-readable media  1022  may be coupled to each other and to the optical system  1002  by a bus  1030 . 
     It is to be appreciated that conditional language used herein such as, among others, “can,” “could,” “might” or “may,” unless specifically stated otherwise, are understood within the context to present that certain examples include, while other examples do not include, certain features, elements and/or steps. Thus, such conditional language is not generally intended to imply that certain features, elements and/or steps are in any way required for one or more examples or that one or more examples necessarily include logic for deciding, with or without user input or prompting, whether certain features, elements and/or steps are included or are to be performed in any particular example. Conjunctive language such as the phrase “at least one of X, Y or Z,” unless specifically stated otherwise, is to be understood to present that an item, term, etc. may be either X, Y, or Z, or a combination thereof. 
     It should be also be appreciated that many variations and modifications may be made to the above-described examples, the elements of which are to be understood as being among other acceptable examples. All such modifications and variations are intended to be included herein within the scope of this disclosure and protected by the following claims. 
     EXAMPLE CLAUSES 
     The disclosure presented herein encompasses the subject matter set forth in the following example clauses. 
     Example 1: A system ( 104 ) comprising: one or more data processing units ( 892 ); and a computer-readable medium ( 894 ) having encoded thereon computer-executable instructions to cause the one or more data processing units ( 892 ) to receive sensor data captured by one or more sensors of a computing device ( 102 ), the sensor data comprising an image ( 108 ) of the real-world environment ( 109 ) and mesh data ( 106 ) derived from a depth scan, the data captured from a first perspective ( 103 ); receive input data indicating a second perspective ( 203 ); generate a three-dimensional representation of the real-world environment ( 109 ) from the image ( 108 ) and the mesh data ( 106 ); and render the image ( 108 ) in a user interface (UI) ( 118 ) from the second perspective ( 203 ) by rendering the three-dimensional representation of the real-world environment from the second perspective ( 203 ). 
     Example 2: A system of example 1, wherein the instructions further cause the one or more data processing units to: receive a past image ( 508 ) and past mesh data ( 506 ) captured before the image ( 108 ) and the mesh data ( 106 ) were captured; and integrate the past image ( 508 ) and past mesh data ( 506 ) into the 3D representation. 
     Example 3: A system of example 1, wherein the instructions further cause the one or more data processing units to: receive a second image ( 608 ) and second mesh data ( 606 ) captured by a second camera ( 610 ); and integrate the second image ( 608 ) and second mesh data ( 606 ) into the 3D representation. 
     Example 4: A system of example 1, wherein the three-dimensional representation is rendered onto at least two displays, one as a floor-map ( 402 ) and one based on the second perspective ( 203 ). 
     Example 5: A system of example 1, wherein a rendering of the three-dimensional representation includes a virtual camera ( 404 ,  612 ) indicating a second perspective ( 203 ) of the real-world environment ( 109 ). 
     Example 6: A system of example 5, wherein moving the virtual camera ( 612 ) within the real-world environment ( 109 ) changes the perspective of another computing device rendering the second perspective ( 203 ) of the real-world environment ( 109 ). 
     Example 7: A system of example 5, wherein changing the perspective of another computing device ( 302 ) rendering the second perspective ( 203 ) of the real-world environment ( 109 ) changes the location or orientation of the virtual camera ( 612 ). 
     Example 8: A system ( 104 ) comprising: one or more data processing units ( 892 ); and a computer-readable medium ( 894 ) having encoded thereon computer-executable instructions to cause the one or more data processing units ( 892 ) to receive sensor data captured by one or more sensors of a computing device ( 102 ), the sensor data comprising an image ( 108 ) of the real-world environment ( 109 ) and mesh data ( 106 ) derived from a depth scan, the data captured from a first perspective ( 103 ); receive input data indicating a second perspective ( 203 ); generate a three-dimensional representation of the real-world environment ( 109 ) from the image ( 108 ) and the mesh data ( 106 ); receive a past image ( 508 ) and past mesh data ( 506 ) captured before the image ( 108 ) and the mesh data ( 106 ) were captured; integrate the past image ( 508 ) and past mesh data ( 506 ) into the 3D representation; and render the image ( 108 ) in a user interface (UI) ( 118 ) from the second perspective ( 203 ) by rendering the three-dimensional representation of the real-world environment from the second perspective ( 203 ). 
     Example 9: The system of example 8, wherein rendering the image ( 108 ) in the UI ( 118 ) is part of a meeting, and wherein the past image ( 508 ) and past mesh data ( 506 ) were captured using the computing device ( 102 ) earlier in the meeting. 
     Example 10: A system of example 8, wherein the instructions further cause the one or more data processing units to: receive a second image ( 608 ) and second mesh data ( 606 ) captured by a second camera  610 ; and integrate the second image ( 608 ) and second mesh data ( 606 ) into the 3D representation. 
     Example 11: A system of example 8, wherein the three-dimensional representation is rendered onto at least two displays, one as a floor-map ( 402 ) and one based on the second perspective ( 203 ). 
     Example 12: A system of example 8, wherein a rendering of the three-dimensional representation includes a virtual camera ( 404 ,  612 ) indicating a second perspective ( 203 ) of the real-world environment ( 109 ). 
     Example 13: A system of example 12, wherein moving the virtual camera ( 612 ) within the real-world environment ( 109 ) changes the perspective of another computing device rendering the second perspective ( 203 ) of the real-world environment ( 109 ). 
     Example 14: A system of example 12, wherein changing the perspective of another computing device ( 302 ) rendering the second perspective ( 203 ) of the real-world environment ( 109 ) changes the location or orientation of the virtual camera ( 612 ). 
     Example 15: A method employed by a computing device ( 104 ) comprising: receiving sensor data captured by one or more sensors of a computing device ( 102 ), the sensor data comprising an image ( 108 ) of the real-world environment ( 109 ) and mesh data ( 106 ) derived from a depth scan, the data captured from a first perspective ( 103 ); receiving input data indicating a second perspective ( 203 ); generating a three-dimensional (3D) representation of the real-world environment ( 109 ) from the image ( 108 ) and the mesh data ( 106 ); receiving a second image ( 608 ) and second mesh data ( 606 ) captured by a second camera ( 610 ); integrating the second image ( 608 ) and second mesh data ( 606 ) into the 3D representation; and rendering the image ( 108 ) in a user interface (UI) ( 118 ) from the second perspective ( 203 ) by rendering the three-dimensional representation of the real-world environment from the second perspective ( 203 ). 
     Example 16: The method of example 15, wherein the second camera ( 610 ) is included in the image ( 108 ), wherein a position of the second camera ( 610 ) is known, wherein a past image ( 508 ) and past mesh data ( 506 ) associated with the position of the second camera ( 610 ), when the second camera ( 610 ) was not present, is available, further comprising: integrating a portion of the past image ( 508 ) that includes the position of the second camera ( 610 ) and a portion of the past mesh data ( 506 ) that includes the position of the second camera ( 610 ) into the three-dimensional representation, so that the rendering of the three-dimensional representation does not include the second camera ( 610 ). 
     Example 17: The method of example 15, wherein the three-dimensional representation is rendered from two perspectives, and wherein a user ( 119 B) is enabled to switch between the two perspectives. 
     Example 18: The method of example 15, wherein a rendering of the three-dimensional representation includes a virtual camera ( 404 ,  612 ) indicating a second perspective ( 203 ) of the real-world environment ( 109 ). 
     Example 19: The method of example 18, wherein the virtual camera ( 404 ,  612 ) is positioned in response to receiving a command from a user ( 119 B), wherein the perspective ( 203 ) is updated in real-time as the user positions the virtual camera ( 404 ,  612 ), and wherein rendering the image ( 108 ) continues while the second perspective ( 203 ) is updated. 
     Example 20: The method of example 15, wherein images ( 108 ) and mesh data ( 106 ) are saved over time, and wherein in response to a user command, the UI ( 118 ) may display a rendering of the 3D representation from the past from a different perspective. 
     Among many other technical benefits, the technologies herein enable more efficient use of computing resources such as processor cycles, memory, network bandwidth, and power, as compared to previous solutions relying upon inefficient manual placement of virtual objects in a 3D environment. Other technical benefits not specifically mentioned herein can also be realized through implementations of the disclosed subject matter. 
     Although the techniques have been described in language specific to structural features and/or methodological acts, it is to be understood that the appended claims are not necessarily limited to the features or acts described. Rather, the features and acts are described as example implementations of such techniques.