Abstract:
A technique for providing a subtle indication of imagery type can be implemented in a software application, such as a mapping application, that displays interactive imagery in a three-dimensional scene and allows users to tap, click, or otherwise select points within the displayed images to pull up corresponding detailed photographs. A pulled-up photograph may be laid out on a surface having a curvature (e.g., the surface of a sphere or a cylinder), in which case the viewport slides along the photograph in a three-dimensional space as the photograph is inspected, or on a surface having no curvature (i.e., the photograph is flat), in which case the viewport pans along the photograph in a two-dimensional space. However, at the time when a user selects a point within the interactive image, the user does not know whether the photograph associated with this point is laid out on a curved surface or a flat surface. To provide a subtle indication of whether the photograph is laid out on a curved surface or a flat surface, the user interface temporarily repositions the viewport along the surface of the photograph.

Description:
FIELD OF TECHNOLOGY 
     The present invention relates to electronic mapping systems and, more specifically, to the use of subtle camera motions to indicate imagery types in a mapping system. 
     BACKGROUND 
     Currently available mapping systems allow the user to interact within a three-dimensional space to explore an area such as a streetscape. In simple implementations, mapping systems present the user with a viewport including a three-dimensional rendering of a given street generated with generic graphics. The generic graphics rendered within a three-dimensional street may include three-dimensional polygon representations of buildings known to exist along the street and projected satellite imagery from above. The mapping system may render these generic graphics from large databases of satellite imagery. 
     However, due to the relatively low quality of satellite imagery from above when viewed at the micro-level of a street, some current mapping systems supplement the generic graphics with user generated imagery, for example two-dimensional photographs and three-dimensional panoramas. These two-dimensional photographs and three-dimensional panoramas provide high quality imagery that may not be available using generic satellite databases, and may provide a level of imagery resolution that is not available using three-dimensional polygon representations of buildings. Users may submit these photographs and panoramas voluntarily to the mapping service, for example, through crowd-sourcing efforts, or the mapping service may commission a large-scale effort to capture street-level photographic and panoramic imagery. 
     More advanced mapping systems may project these user generated two-dimensional and three-dimensional photographs together onto the three-dimensional space, for example a streetscape, to better allow the user to explore the three-dimensional space. The user may select the user-generated imagery projected onto the three-dimensional space in order to interact with the user-generated imagery independent of the three-dimensional space. 
     One issue that may arise when selecting two-dimensional or three-dimensional imagery is that the user may not understand whether the imagery is in fact two-dimensional or three-dimensional or how to best navigate the user-generated imagery. For example, a user may click on and navigate a user-generated two-dimensional photo by first selecting the photo in the three-dimensional space and panning the photo in two dimensions. The user may alternatively click on and navigate a user-generated three-dimensional panorama in the three-dimensional space by rotating the panorama in three dimensions. When the user selects the user-generated imagery in the three-dimensional space, the user may not understand which user-generated imagery is two-dimensional and which user-generated imagery is three-dimensional. Thus, the user may have no indication or instructions to navigate the selected user-generated imagery in two-dimensions or three-dimensions in the most efficient or intuitive means possible. 
     Some mapping systems may indicate, through a label or other obtrusive rendered indicator, that the user may navigate the user-generated imagery in two or three dimensions. However, these labels or rendered indicators typically obscure the image or distract the user from the image. Alternatively, the label or rendered indicator may not be immediately apparent to the user, presenting the same issue as providing no indicator whatsoever. 
     SUMMARY 
     Features and advantages described in this summary and the following detailed description are not all-inclusive. Many additional features and advantages will be apparent to one of ordinary skill in the art in view of the drawings, specification, and claims hereof. Additionally, other embodiments may omit one or more (or all) of the features and advantages described in this summary. 
     In one embodiment, a computer-implemented method indicates the curvature of a digital image via rendered subtle camera motions on a user interface. The computer-implemented method includes rendering a representation of the digital image on a user interface, enabling selection of the representation of the digital image via the user interface, determining the curvature of at least one axis of the digital image, and rendering an animated indication of the curvature of at least one axis of the digital image via the user interface. 
     In another embodiment, a computer system indicates the curvature of a digital image by rendering subtle camera motions via a user interface. The computer system includes a first processor, a first memory communicatively coupled to the first processor, and a user interface communicatively coupled to the first processor. The first memory includes a digital image and instructions that, when executed by the first processor, cause the first processor to render a representation of the digital image on the user interface, receive a selection of the representation of the digital image from the user interface, determine the curvature of at least one axis of the digital image, and render an animated indication of the curvature of at least one axis of the digital image via the user interface. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a high-level view of a stand-alone system for indicating imagery type with subtle camera motions; 
         FIG. 2  is a high-level view of a client-server system for indicating imagery type with subtle camera motions; 
         FIG. 3  is an illustration of a three-dimensional mapping application window with rendered two-dimensional and three-dimensional imagery available for a user to select; 
         FIG. 4  is a flowchart illustrating a high-level method of selecting two-dimensional and three-dimensional photographs within a three-dimensional mapping system; 
         FIG. 5  is an illustration of a two-dimensional viewport including a flat photograph and an indication of the movements available for the viewport in a two-dimensional flat space; 
         FIG. 6  is a flowchart illustrating a method that indicates the movements available for a viewport within the selected two-dimensional flat photograph; 
         FIG. 7  is an illustration of a three-dimensional cylindrical viewport including a three-dimensional cylindrical photograph and an indication of the movements available for the viewport in a three-dimensional cylindrical space; 
         FIG. 8  is a flowchart illustrating a method that indicates the movements available for a viewport within the selected three-dimensional cylindrical photograph; 
         FIG. 9  is an illustration of a three-dimensional spherical viewport including a three-dimensional spherical photograph and an indication of the movements available for the viewport in a three-dimensional spherical space; 
         FIG. 10  is a flowchart illustrating a method that indicates the movements available for a viewport within the selected three-dimensional spherical photograph; and 
         FIG. 11  is an exemplary computing system that may implement various portions of a system for indicating the movements available for a viewport within selected two-dimensional and three-dimensional photographs. 
     
    
    
     The figures depict a preferred embodiment for purposes of illustration only. One skilled in the art may readily recognize from the following discussion that alternative embodiments of the structures and methods illustrated herein may be employed without departing from the principles described herein. 
     DETAILED DESCRIPTION 
     An image display system, which displays images in a three dimensional scene to a user, uses subtle camera motions that change the perspective of a user in the scene to indicate the curvature or type of the image being displayed, such whether the image is a panorama, a spherical scene, or a flat photograph, to enable a user to easily determine the navigation options available for the image. The image display system that uses subtle camera motions, such as panning, rotating, zooming, or flipping the image using the image display system, intuitively indicates to the user that an image contains or lacks curvature by slightly changing the perspective of the user without obscuring the image with a label or requiring the user to read a written label. The subtle camera motions also provide the benefit of demonstrating the navigational options available to the user without obscuring the image with icons or requiring the user to read cumbersome navigation instructions. Thus, the image display system that uses subtle camera motions to indicate image type provides the distinct advantage of indicating curvature in an image and instructing the user of the available navigation options without requiring the user to observe anything other than the image itself and the subtle camera motions thereof. 
     Turning to  FIG. 1 , an image display system  100 , which uses subtle camera motions to enable a user to easily determine the navigational options available for the image, includes an image rendering unit  110  that generally stores and displays images on a display  120 , and that accepts user inputs from a keyboard  130  and pointing device  140 . The image rendering unit  110  stores images of differing curvatures in a database  150  that a processor  160  retrieves and renders on the display  120  by executing instructions stored in a memory  170 . Generally speaking, the processor  160  determines the curvature of the image retrieved from the database  150  and renders subtle camera motions on the display  120  to both indicate the curvature of the image and instruct the user of the system  100  how to navigate the image. The user of the system  100 , having observed the subtle camera motions on the display  120 , and aware of the curvature of the image and available navigational options, may navigate the image more effectively using the keyboard  130  and pointing device  140 . 
     In another embodiment, for example, the system  200  illustrated in  FIG. 2 , the database containing the imagery of differing types resides within a back-end server  202 , instead of a singular image rendering unit  110  in the embodiment illustrated in  FIG. 1 . In the system  200  of  FIG. 4 , front-end client  204 , connected to the back-end server  202  through a network  206 , renders subtle camera motions similar to the image rendering unit  110 , to enable a user to easily determine the navigational options available for a particular image retrieved from the back-end server  202 . 
     Generally,  FIG. 2  illustrates the system  200  as a system that renders two-dimensional and three-dimensional images on a display for a user and that indicates the image type and available navigational options with subtle camera motions. The system  200  generally includes a back-end server  202  and a front-end client  204  interconnected by a communication network  206 . The front-end client  204  includes executable instructions  208  contained in a memory  210 , a processor  212 , a display  214 , a keyboard  218 , a pointing device  220 , and a client network interface  222  communicatively coupled together with a front-end client bus  224 . The client network interface  222  communicatively couples the front-end client  204  to the network  206 . The back-end server  202  includes instructions  222  contained in a memory  224 , a processor  226 , a database containing scenes  230 , a database containing two-dimensional and three-dimensional photographs  232 , and a back-end network interface  140  communicatively coupled together with a back-end server bus  242 . 
     Generally, the front-end client  204 , executing instructions  208  in the processor  212 , renders photographs retrieved from the photograph database  232  onto a three dimensional scene retrieved from the scenes database  230  and renders the photographs and the scene together on the display  214 . The user generally interacts with the front-end client  204  by using the pointing device  220  and the keyboard  218  to select two-dimensional and three-dimensional photographs in a three-dimensional scene rendered on a display  214 . Selecting a two-dimensional or three dimensional photograph from a three-dimensional scene causes the processor  212  to send a request to the back-end server  202  to execute instructions  222  to retrieve the selected photograph from to the back-end server  202  and to transmit the selected photograph back to the front-end client  204 . The front-end client  204 , executing instructions  208 , indicates the type of imagery retrieved, for example, whether the image is two-dimensional or three-dimensional, by automatically rendering subtle camera motions on the display  214 , thereby instructing the user how to navigate the image more effectively. 
     The display  206  in the front-end client  205  may render an application window  300  as illustrated in  FIG. 3 . The user navigates a three dimensional scene rendered in the mapping application window  300  containing, for example, a ground-level streetscape depicting the Eiffel Tower in Paris, France using the keyboard  215  and pointing device  220 . The mapping application window  300  includes a search box  305  to enter a destination, a cursor  306  controlled by the pointing device  220  that the user uses to navigate and select items within the application window  300 , and a viewport  310 . The three-dimensional scene depicted within the viewport  310  may contain a two-dimensional flat photograph  320  rendered into the three-dimensional scene within the viewport  310  with outlining indicating the boundaries of the two-dimensional flat photograph  320 . The outlining of the two-dimensional flat photograph  320  becomes more distinctive when the cursor  306  hovers over the two-dimensional flat photograph  320 . The distinctive highlighting of the two-dimensional flat photograph  320  indicates that the two-dimensional photograph  320  may expand with options to navigate the two-dimensional photograph  320  independent of the three-dimensional scene within the viewport  210 . The user may select the two-dimensional flat photograph  320  for example with a click of the pointing device  220  in order to navigate the two-dimensional flat photograph  320  independent of the three-dimensional scene. 
     In a similar manner, the three dimensional scene within the viewport  310  contains a three-dimensional cylindrical photograph  330  that is rendered onto part of the three-dimensional scene with outlining indicating the boundaries of the three-dimensional cylindrical photograph  330 . Again, the outlining of the three-dimensional cylindrical photograph  330  may become more distinctive when the cursor  306  hovers over the three-dimensional cylindrical photograph  330 . The distinctive highlighting of the three dimensional cylindrical photograph  230  indicates that the three dimensional cylindrical photograph  330  may expand with options to navigate the three-dimensional cylindrical photograph  330  independent of the three dimensional scene. The user may select the three-dimensional cylindrical photograph  330  for example with a click of the pointing device  220  in order to navigate the three-dimensional cylindrical photograph  330  independent of the three-dimensional scene. 
     Likewise, the three-dimensional scene within the viewport  310  may contain a three-dimensional spherical photograph  340  that is rendered onto part of the three-dimensional scene with outlining indicating the boundaries of the three-dimensional spherical photograph  340 . Again, the outlining of the three-dimensional spherical photograph  340  may become more distinctive when the cursor  306  hovers over the three-dimensional spherical photograph  340 . The distinctive highlighting of the three-dimensional spherical photograph  340  indicates that the three-dimensional spherical photograph  340  may expand with options to navigate the three-dimensional spherical photograph  340  independent of the three dimensional scene. The user may select the three-dimensional spherical photograph  340  for example with a click of the pointing device  220  in order to navigate the three-dimensional spherical photograph  340  independent of the three-dimensional scene. 
     A user may interact with the application window  300  rendered in the display  214  using the method  400  illustrated in  FIG. 4 . The flowchart illustrated in  FIG. 4  illustrates a method  400  that uses the system  200  to render mixed two-dimensional and three-dimensional photographs in a three-dimensional scene and allow the user to select an individual photograph for rendering and navigation independent from the three-dimensional scene. 
     The user, following the process  400 , selects among the two-dimensional flat photograph  320 , the three-dimensional cylindrical photograph  330 , or the three-dimensional spherical photograph  340  illustrated in  FIG. 3 . More particularly, the method  400  begins at step  410  by executing instructions  208  in the processor  212  to send a request from the front-end client  204  to the back-end server  202  via the network  206  for retrieval of a three dimensional scene in the scenes database  230 . The system  200  specifies a particular three-dimensional scene to retrieve from the scenes database  230  for example using the search box  305  in  FIG. 3 . The back-end server  202 , executing instructions  222 , retrieves the indicated three-dimensional scene from the scenes database  230  and transmits the three-dimensional scene back to the front-end client  204  via the network  206 . The front-end client  204 , executing instructions  208  in the processor  212 , stores the three-dimensional scene in the memory  210 , and renders the three-dimensional scene in the display  214 . 
     The method  400  continues with step  420  that retrieves the two-dimensional and three-dimensional photographs that may exist within the boundaries of the viewport  310  of the three-dimensional scene from the back-end server  202  and renders the two-dimensional and three-dimensional photographs on the display  214  together with the three-dimensional scene. The processor  212 , executing instructions  208 , transmits identifying information about the currently displayed three-dimensional scene to the back-end server  202  via the network  206 . The back-end server  202 , executing instructions  222  in the processor  226 , retrieves the two-dimensional and three-dimensional photographs within the three-dimensional scene from the photographs database  232  and transmits the photographs back to the front-end client  204  via the network  206 . The front-end client  204 , executing instructions  208  in the processor  212 , stores the photographs in the memory  210  and renders the photographs into the three-dimensional scene on the display  214 . In one case, the rendered photographs  320 ,  330 , and  340  appear as continuous illustrations of the three-dimensional scene in the viewport  310 . 
     The method  400  continues to step  430  where a user interacting with the system  200  using the pointing device  220  and the keyboard  218  selects a particular photograph in the three-dimensional scene rendered on the display  214 . The user selects a particular two-dimensional or three-dimensional photograph in the three-dimensional scene for example with the click of the pointing device  220  within the outlined boundaries of a photograph. Selecting a particular photograph causes the processor  212  to execute instructions  208  that determine if the selected photograph stored in the memory  210  contains or lacks curvature, and is two-dimensional, three-dimensional cylindrical, or three-dimensional spherical. 
     If the processor  212 , executing instructions  208  determines at step  430  that the pointing device  220  was within the boundaries of a two-dimensional photograph, for example the two-dimensional photograph  320  in  FIG. 3 , then the processor executes the instructions  208  in the processor  212  at a step  440 . At the step  440  the processor  212  executes the instructions  208  to begin the process  670 , illustrated in  FIG. 6 , that displays the two-dimensional photograph  320  independent of the three-dimensional scene and subtly indicates with an automatic camera motion that the two-dimensional photograph  220  lacks curvature and is in fact two-dimensional and can be navigated in a two-dimensional manner. 
     Turning to  FIG. 5 , the user navigates the selected two-dimensional flat photograph  320  using an application window  501  rendered on the display  214 . The application window  501  contains similar features as the application window  300  in  FIG. 3 , for example a search box  505 , and a viewport  510 . However, the user may navigate the two-dimensional flat photograph  320  using the application window  501  independent from the three-dimensional scene in the viewport  310  in  FIG. 3 . The user may navigate the flat two-dimensional photograph  320  in the vertical direction  520  or horizontal direction  530  from the perspective of a user represented by a virtual camera  540 . The viewport  510  may include a portion of the two-dimensional flat photograph  320  as illustrated, or include the entire two-dimensional flat photograph  320 . The viewport  510  may be restricted from navigating outside of the boundaries of the flat photograph  320 . 
     In order to indicate to the user the available vertical  520  and horizontal  530  navigation capabilities, and to illustrate the that the two-dimensional flat photograph  320  lacks curvature, the viewport  510  moves along the vertical  520  and horizontal  530  directions of the two-dimensional photograph  320  automatically prior to allowing the user to navigate of the two-dimensional flat photograph  320  within the viewport  510 . The automatic movement of the viewport  510  may include a circular or strictly up and down motion and continues for a short duration prior to ceasing. The automatic movement of the viewport  510  in the vertical  520  and horizontal  530  directions along the two-dimensional flat photograph  320  illustrates a two-dimensional perspective for the virtual camera  540  and indicates the available navigation options for the user. Thus, when the automatic movement of the viewport  510  ceases, the user is aware of the available navigation options and that the two-dimensional photograph  320  lacks curvature prior to any user directed navigation. 
     A method  670  illustrated in  FIG. 6 , continuing from step  440  in  FIG. 4 , generally illustrates how the system  200  renders a subtle camera motion to indicate the lack of curvature of a two-dimensional flat photograph and demonstrate the available navigation options. The processor  212 , executing instructions  208  at a step  672  renders part or all of the two-dimensional photograph  320  in a viewport of an application window, similar to the viewport  510  of the application window  501  illustrated in  FIG. 5 . The system  200  indicates that the photograph is in fact two-dimensional, lacks curvature, and may demonstrate the available vertical range of motion of the viewport within the photograph to the user by executing instructions  208  in the processor  212  at step  674  to render the viewport  510  in the application window  501  on the display  214  moving vertically up the two-dimensional photograph  320  a short distance. The processor  212  continues to render the viewport  510  within the application window  501  moving vertically down the two-dimensional photograph  320  a short distance, returning to the original rendered position on the photograph  320 . 
     Likewise to further indicate to the user that the photograph is in fact two-dimensional, lacks curvature, and to possibly demonstrate the available horizontal range of motion of the viewport within the photograph, the processor  212  executing instructions  208  at step  676  renders the viewport  510  in the application window  501  on the display  214  moving horizontally left along the two-dimensional photograph  320  a short distance. The processor  212  continues to render the viewport  510  within the application window  501  moving horizontally right along the two-dimensional photograph  320  a short distance, returning to the original rendered position on the photograph  320 . 
     The vertical and horizontal motion of the viewport within the two-dimensional photograph  320  subtly indicates to the user that the photograph is in fact two dimensional, lacks curvature, and demonstrates the available navigation options without obscuring the photograph with indicators or printed instructions. While the steps  674  and  676  recite embodiments including vertical and horizontal subtle motions of the viewport  510  along the photograph  320  to indicate image type, additional movements such as spiral, circular, or diagonal movements may be used to provide additional subtle indications of the two-dimensional nature of the photograph and demonstrate the available navigation options. 
     Continuing to step  678 , the processor  212 , executing instructions  208  holds the photograph  320  stationary and awaits user manipulation of the photograph  320  with the pointing device  220  or keyboard  218  within the viewport  520  in the two-dimensional horizontal and vertical direction, as demonstrated with the automatic subtle vertical and horizontal motions in steps  674  and  676 . 
     Returning to the method  400  illustrated in  FIG. 4 , if the processor  212 , executing instructions  208  determines at the step  430  that the pointing device  220  was within the boundaries of a three-dimensional cylindrical photograph, for example, the three-dimensional cylindrical photograph  330  in  FIG. 3 , then the processor executes instructions  208  in the processor  212  at step  450 . At the step  450  the processor  212  executes instructions  208  to begin a process  880 , illustrated in  FIG. 8 , that displays the three-dimensional cylindrical photograph  330  independent from the three-dimensional scene and subtly indicates with an automatic camera motion that the three-dimensional cylindrical photograph  330  is in fact three-dimensional, contains curvature in one axis, and can be navigated in a three-dimensional cylindrical manner. 
     Turning to  FIG. 7 , the user navigates the selected three-dimensional cylindrical photograph  330  in an application window  701  rendered on the display  214 . The application window  701  contains similar features as the application window  300  in  FIG. 3  and the application window  501  in  FIG. 5 . For example, the application window  701  contains a search box  705  and a viewport  710 . However, the user navigates the three-dimensional cylindrical photograph  230  independent from the three-dimensional scene in the viewport  210  in  FIG. 2 . The user navigates the three-dimensional cylindrical photograph  330  by rotating horizontally along a vertical axis  720  of the three-dimensional cylindrical photograph  330  and panning the three-dimensional cylindrical photograph  330  vertically along the vertical axis  720  from the perspective of a user represented by a virtual camera  730 . The viewport  710  may include a portion of the three-dimensional cylindrical photograph  330  as illustrated, or include the entire three-dimensional cylindrical photograph  330 . The viewport  710  may be restricted from navigating outside the boundaries of the three-dimensional cylindrical photograph  330 . 
     In order to indicate the available horizontal rotation and vertical panning navigation capabilities of the viewport  710  along the horizontal axis  720  of the three-dimensional cylindrical photograph  330  and to illustrate the three-dimensional nature of the three-dimensional cylindrical photograph  330 , the viewport  710  automatically moves prior to allowing navigation. The automatic movement of the viewport  710  may include a circular or strictly vertical and horizontal movement and the movement may continue for a short duration prior to ceasing. The automatic movement of the viewport  710  in the vertical and horizontal directions along the vertical axis  720  of the three-dimensional cylindrical photograph  330  illustrates a three-dimensional perspective for the virtual camera  730 , demonstrates the curvature in one axis of the photograph  330 , and indicates the available navigational options for the user. When the automatic movement of the viewport  710  ceases, the available navigational options for the three-dimensional cylindrical photograph  330  are apparent to the user prior to any user directed navigation. Thus, when a user begins navigation of the three-dimensional cylindrical photograph  330  after the automatic movement of the viewport  710  ceases, the user understands the available navigations options of the three-dimensional photograph  330 . 
     Turning to the method  880  illustrated in  FIG. 8 , continuing from step  450  in  FIG. 4 , the processor  212 , executing instructions  208  at step  882  renders the three-dimensional cylindrical photograph  330  independent of the three-dimensional scene on the display  214 . The processor  212 , executing instructions  208  at step  882  may render part or all of the three-dimensional cylindrical photograph  330  in a viewport of an application window, similar to the viewport  710  of the application window  701  illustrated in  FIG. 7 . In order to indicate to the user that the photograph is three-dimensional cylindrical containing curvature in one axis but lacking curvature in another axis, and to demonstrate the available vertical range of motion of the viewport within the photograph, the processor  212  executing instructions  208  at step  884  renders the viewport  710  in the application window  701  on the display  214  panning vertically up the three-dimensional cylindrical photograph  330  a short distance. The processor  212  continues to render the viewport  710  within the application window  701  panning vertically down the three-dimensional cylindrical photograph  330  a short distance, returning to the original rendered position on the photograph  330 . 
     Likewise, to further indicate to the user that the photograph is three-dimensional cylindrical, lacking curvature in one axis but containing curvature in another axis, and to demonstrate the available horizontal rotation of the viewport within the photograph, the processor  212  executing instructions  208  at step  886  renders the viewport  710  in the application window  701  on the display  214  rotating horizontally left along the three-dimensional cylindrical photograph  330  a short distance. The processor  212  continues to render the viewport  710  within the application window  701  rotating horizontally right along the three-dimensional cylindrical photograph  330  a short distance, returning to the original rendered position on the photograph  330 . 
     The vertical panning and horizontal rotation of the viewport within the three-dimensional cylindrical photograph subtly indicates to the user that the photograph is in fact three-dimensional cylindrical containing curvature in one axis and lacking curvature in another axis, and demonstrates the navigation options without obscuring the photograph with indicators or printed instructions. While steps  884  and  886  recite embodiments comprising vertical and horizontal subtle motion of the viewport  710  along the photograph  330 , additional movements such as spiral, circular, or diagonal movements may provide additional subtle indications of the three-dimensional cylindrical nature of the photograph and the curvature of the axes of the photograph, and the navigation options available to the user along each axis. 
     Continuing to a step  888 , the processor  212 , executing instructions  208  holds the photograph  330  stationary and awaits user manipulation of the photograph  330  with the pointing device  220  or keyboard  218  within the viewport  710  in the two-dimensional horizontal and vertical direction, as demonstrated with the automatic subtle vertical and horizontal motion in steps  884  and  886 . 
     Returning again to method  400  illustrated in  FIG. 4 , if the processor  212 , executing instructions  208  determines at the step  430  that the pointing device  220  was within the boundaries of a three-dimensional spherical photograph, for example the three-dimensional spherical photograph  340  in  FIG. 3 , then the processor  212  may execute instructions  208  in the processor  212  at step  460 . At step  460  the processor  212  may execute instructions  208  to begin the process  1090 , illustrated in  FIG. 10 , that displays the three-dimensional spherical photograph  340  independent from the three-dimensional scene and subtly indicates with an automatic camera motion that the three-dimensional spherical photograph  340  is in fact three-dimensional and contains curvature in more than one axis, and can be navigated in a three-dimensional spherical manner. 
     Turning to  FIG. 9 , the user navigates the selected three-dimensional spherical photograph  340  using an application window  901  rendered on the display  214 . The application window  901  may contain similar features as the application window  300  in  FIG. 3 , the application window  501  in  FIG. 5 , and the application window  701  in  FIG. 7 . For example, the application window  901  contains a search box  905  and a viewport  910 . However, the user navigates the three-dimensional spherical photograph  340  independent from the three-dimensional scene in the viewport  310  in  FIG. 3 . The user navigates the three-dimensional spherical photograph  340  by vertically and horizontally rotating the viewport  910  from the perspective of a virtual camera  920  representing a user at the center  930  of a virtual sphere. The viewport  910  may include a portion of the three-dimensional spherical photograph  340  as illustrated, or include the entire three-dimensional spherical photograph  340 . The viewport  910  may be restricted from navigating outside the boundaries of the three-dimensional spherical photograph  340 . 
     In order to indicate to the user the available horizontal and vertical rotation navigation capabilities of the viewport  910  from the perspective of the virtual camera  920  and illustrate the three-dimensional nature of the spherical photograph  340  containing curvature in more than one axis, the viewport  910  automatically moves prior to allowing navigation. The automatic movement of the viewport  910  includes a circular or strictly vertical and horizontal movement and may continue for a short duration prior to ceasing. The automatic movement of the viewport  910  in the vertical and horizontal directions from the center  930  of a virtual sphere illustrates a three-dimensional perspective for the virtual camera  920  and indicates the available navigation options for the user. When the automatic movement of the viewport  910  ceases, the available navigation options are apparent prior to any user directed navigation. Thus, when a user begins navigation of the viewport  910 , the user understands the available navigation options of the three-dimensional photograph  340  under navigation. 
     Turning to the method  1090  illustrated in  FIG. 10 , continuing from step  460  in  FIG. 4 , the processor  212 , executing instructions  208  at a step  892  renders the three-dimensional spherical photograph  340  independent of the three-dimensional scene rendered on the display  214 . The processor  212 , executing instructions  208  at a step  1092  may render part or all of the three-dimensional spherical photograph  340  in a viewport of an application window, similar to the viewport  910  of the application window  901  illustrated in  FIG. 9 . To indicate to the user that the photograph is three-dimensional spherical containing curvature in more than one axis, and to demonstrate the available vertical range of motion of the viewport within the photograph, the processor  212  executing instructions  208  at a step  1094  renders the viewport  910  in the application window  901  on the display  214  rotating vertically up the three-dimensional spherical photograph  340  a short distance. The processor  212  continues to render the viewport  910  within the application window  901  rotating vertically down the three-dimensional spherical photograph  340  a short distance, returning to the original rendered position on the photograph  340 . 
     Likewise, to further indicate to the user that the photograph is three-dimensional spherical containing curvature in more than one axis, and to demonstrate the available horizontal rotation of the viewport within the photograph, the processor  212  executing instructions  208  at step  1096  renders the viewport  910  in the application window  901  on the display  214  rotating horizontally left along the three-dimensional spherical photograph  340  a short distance. The processor  212  continues to render the viewport  910  within the application window  901  rotating horizontally right along the three-dimensional cylindrical photograph  340  a short distance, returning to the original rendered position on the photograph  340 . 
     The vertical and horizontal rotation of the viewport within the three-dimensional spherical photograph subtly indicates to the user that the photograph is in fact three-dimensional spherical containing curvature in more than one axis, and demonstrate the available navigation options without obscuring the photograph with indicators or printed instructions. While steps  1094  and  1096  recite embodiments including vertical and horizontal subtle motions of the viewport  910  along the photograph  340 , additional movements such as spiral, circular, or diagonal movements may provide subtle indications of the three-dimensional spherical nature of the photograph containing curvature in more than one axis, and the available navigation options in each axis. 
     Continuing to step  1098 , the processor  212 , executing instructions  208  holds the photograph  340  stationary and awaits user manipulation of the photograph  330  with the pointing device  220  or keyboard  218  within the viewport  910  in the three-dimensional horizontal and vertical directions, as demonstrated with the automatic subtle vertical and horizontal motion in steps  1094  and  1096 . 
       FIG. 11  illustrates a generic computing system  1101  that the system  200  may use to implement the front-end client  204  in  FIG. 2 , and/or the back-end server  202 . The generic computing system  1101  comprises a processor  1105  for executing instructions that may be stored in volatile memory  1110 . The memory and graphics controller hub  1120  connects the volatile memory  1110 , processor  1105 , and graphics controller  1115  together. The graphics controller  1115  may interface with a display  1125  to provide output to a user. A clock generator  1130  drives the  1105  processor and memory and graphics controller hub  1120  that may provide synchronized control of the system  1101 . The I/O controller hub  1135  connects to the memory and graphics controller hub  1120  to comprise an overall system bus  1137 . The hub  1135  may connect the lower speed devices, such as the network controller  1140 , non-volatile memory  1145 , and serial and parallel interfaces  1150 , to the overall system  1101 . The serial and parallel interfaces may  1150  include a keyboard  1155  and pointing device  1160  for interfacing with a user. 
       FIGS. 1-11  illustrate a system and method for indicating imagery type with subtle camera motions. The system comprises a front-end client that receives user interactions and displays three-dimensional scenes and two-dimensional and three-dimensional photographs. The back-end server retrieves three-dimensional scenes and two and three-dimensional photographs from databases. The method provides an automatic subtle camera movement based on imagery type to indicate whether a photograph is two or three dimensional and provides exemplary available movements of a viewport along the two and three-dimensional photographs. 
     Additionally, certain embodiments are described herein as including logic or a number of components, modules, or mechanisms. Modules may constitute either software modules (e.g., code or instructions embodied on a machine-readable medium or in a transmission signal, wherein a processor executes the code) or hardware modules. A hardware module is tangible unit capable of performing certain operations and may be configured or arranged in a certain manner. In example embodiments, software (e.g., an application or application portion) may configure one or more computer systems (e.g., a standalone, client or server computer system) or one or more hardware modules of a computer system (e.g., a processor or a group of processors) as a hardware module that operates to perform certain operations as described herein. 
     In various embodiments, a hardware module may be implemented mechanically or electronically. For example, a hardware module may comprise dedicated circuitry or logic that is permanently configured (e.g., as a special-purpose processor, such as a field programmable gate array (FPGA) or an application-specific integrated circuit (ASIC)) to perform certain operations. A hardware module may also comprise programmable logic or circuitry (e.g., as encompassed within a general-purpose processor or other programmable processor) that is temporarily configured by software to perform certain operations. It will be appreciated that the decision to implement a hardware module mechanically, in dedicated and permanently configured circuitry, or in temporarily configured circuitry (e.g., configured by software) may be driven by cost and time considerations. 
     Accordingly, the term “hardware module” should be understood to encompass a tangible entity, be that an entity that is physically constructed, permanently configured (e.g., hardwired), or temporarily configured (e.g., programmed) to operate in a certain manner or to perform certain operations described herein. As used herein, “hardware-implemented module” refers to a hardware module. Considering embodiments in which hardware modules are temporarily configured (e.g., programmed), each of the hardware modules need not be configured or instantiated at any one instance in time. For example, where the hardware modules comprise a general-purpose processor configured using software, the general-purpose processor may be configured as respective different hardware modules at different times. Software may accordingly configure a processor, for example, to constitute a particular hardware module at one instance of time and to constitute a different hardware module at a different instance of time. 
     Hardware modules can provide information to, and receive information from, other hardware modules. Accordingly, the described hardware modules may be regarded as being communicatively coupled. Where multiple of such hardware modules exist contemporaneously, communications may be achieved through signal transmission (e.g., over appropriate circuits and buses) that connect the hardware modules. In embodiments in which multiple hardware modules are configured or instantiated at different times, communications between such hardware modules may be achieved, for example, through the storage and retrieval of information in memory structures to which the multiple hardware modules have access. For example, one hardware module may perform an operation and store the output of that operation in a memory device to which it is communicatively coupled. A further hardware module may then, at a later time, access the memory device to retrieve and process the stored output. Hardware modules may also initiate communications with input or output devices, and can operate on a resource (e.g., a collection of information). 
     The various operations of example methods described herein may be performed, at least partially, by one or more processors that are temporarily configured (e.g., by software) or permanently configured to perform the relevant operations. Whether temporarily or permanently configured, such processors may constitute processor-implemented modules that operate to perform one or more operations or functions. The modules referred to herein may, in some example embodiments, comprise processor-implemented modules. 
     Similarly, the methods, processes, or routines described herein may be at least partially processor-implemented. For example, at least some of the operations of a method may be performed by one or processors or processor-implemented hardware modules. The performance of certain of the operations may be distributed among the one or more processors, not only residing within a single machine, but deployed across a number of machines. In some example embodiments, the processor or processors may be located in a single location (e.g., within a home environment, an office environment or as a server farm), while in other embodiments the processors may be distributed across a number of locations. 
     The one or more processors may also operate to support performance of the relevant operations in a “cloud computing” environment or as a “software as a service” (SaaS). For example, at least some of the operations may be performed by a group of computers (as examples of machines including processors), these operations being accessible via a network (e.g., the Internet) and via one or more appropriate interfaces (e.g., application program interfaces (APIs).) 
     The performance of certain of the operations may be distributed among the one or more processors, not only residing within a single machine, but also deployed across a number of machines. In some example embodiments, the one or more processors or processor-implemented modules may be located in a single geographic location (e.g., within a home environment, an office environment, or a server farm). In other example embodiments, the one or more processors or processor-implemented modules may be distributed across a number of geographic locations. 
     Some portions of this specification are presented in terms of algorithms or symbolic representations of operations on data stored as bits or binary digital signals within a machine memory (e.g., a computer memory). These algorithms or symbolic representations are examples of techniques used by those of ordinary skill in the data processing arts to convey the substance of their work to others skilled in the art. As used herein, an “algorithm” is a self-consistent sequence of operations or similar processing leading to a desired result. In this context, algorithms and operations involve physical manipulation of physical quantities. Typically, but not necessarily, such quantities may take the form of electrical, magnetic, or optical signals capable of being stored, accessed, transferred, combined, compared, or otherwise manipulated by a machine. It is convenient at times, principally for reasons of common usage, to refer to such signals using words such as “data,” “content,” “bits,” “values,” “elements,” “symbols,” “characters,” “terms,” “numbers,” “numerals,” or the like. These words, however, are merely convenient labels and are to be associated with appropriate physical quantities. 
     Unless specifically stated otherwise, discussions herein using words such as “processing,” “computing,” “calculating,” “determining,” “presenting,” “displaying,” or the like may refer to actions or processes of a machine (e.g., a computer) that manipulates or transforms data represented as physical (e.g., electronic, magnetic, or optical) quantities within one or more memories (e.g., volatile memory, non-volatile memory, or a combination thereof), registers, or other machine components that receive, store, transmit, or display information. 
     As used herein any reference to “some embodiments” or “an embodiment” means that a particular element, feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment. The appearances of the phrase “in some embodiments” in various places in the specification are not necessarily all referring to the same embodiment. 
     Some embodiments may be described using the expression “coupled” and “connected” along with their derivatives. For example, some embodiments may be described using the term “coupled” to indicate that two or more elements are in direct physical or electrical contact. The term “coupled,” however, may also mean that two or more elements are not in direct contact with each other, but yet still co-operate or interact with each other. The embodiments are not limited in this context. 
     Further, the figures depict preferred embodiments of a system for providing subtle camera motions to indicate imagery type. One skilled in the art will readily recognize from the following discussion that alternative embodiments of the structures and methods illustrated herein may be employed without departing from the principles described herein 
     Upon reading this disclosure, those of skill in the art will appreciate still additional alternative structural and functional designs for a system for providing subtle camera motions to indicate imagery type through the disclosed principles herein. Thus, while particular embodiments and applications have been illustrated and described, it is to be understood that the disclosed embodiments are not limited to the precise construction and components disclosed herein. Various modifications, changes and variations, which will be apparent to those skilled in the art, may be made in the arrangement, operation and details of the method and apparatus disclosed herein without departing from the spirit and scope defined in the appended claims.