arcAstroVR
Software for visualization of archaeological structures and the background celestial body

Users Manual
Ver.0.16（July 25, 2022）

Table of Content
Change log...................................................................................................................................................2
1.File structure..............................................................................................................................................5
1-1.Stellarium app.....................................................................................................................................5
1-2.arcAstroVR app...................................................................................................................................5
1-3.Dataset for arcAstroVR.......................................................................................................................5
2.Overview...................................................................................................................................................6
2-1.Functional overview............................................................................................................................6
2-2.Reproduction accuracy........................................................................................................................7
3.Installation and configuration...................................................................................................................93-1.Stellarium settings...............................................................................................................................93-2.Recommended display settings.........................................................................................................10
3-3. Time zone setting.............................................................................................................................11
4.Creating a dataset....................................................................................................................................11
4-1.Dataset file structure..........................................................................................................................11
4-2. Creation of Wide-area terrain / Narrow-area terrain data.................................................................11
4-3.Creating a configuration file (dataset.txt).........................................................................................12
5.Start up....................................................................................................................................................13
6.Operation of arcAstroVR........................................................................................................................13
6-1. Date and time setting........................................................................................................................13
6-2. Move operation of the observer.......................................................................................................13
6-3. Display Settings...............................................................................................................................15
6-4. Top Bar and Information Window...................................................................................................16
7. HMD（Head Mount Display）.................................................................................................................19
7-1. Head Mount Display (HMD) output settings...................................................................................19
7-2. Operation with Head Mount Display...............................................................................................19
8. Dome Master..........................................................................................................................................20
8-1.Dome Master Settings.......................................................................................................................20
9.Advanced display using Stellarium settings...........................................................................................21
9-1.Starry sky display settings.................................................................................................................21
9-2. Atronomical Calculation Window....................................................................................................22
9-3.Other settings....................................................................................................................................22
10. Licenses................................................................................................................................................23
Unity built-in package.............................................................................................................................23
Contact information...................................................................................................................................231

Change log
AppUpdate date

Update content

0.8.1

March 26, 2021

First draft

0.9.1

May 6, 2021

Correction of description due to the latest status of Stellarium-Since the precautions for "1-1.Stellarium App" are no longer necessary, the description has
been deleted.
The following corrections due to data file format changes-Corrected the terrain data file name in "2-2-1 Terrain accuracy" "4-1. Data set fileconfiguration" "4-2. Base terrain data creation"
The following corrections due to data management changes-Additional description to "3-1. Stellarium settings" to specify the ArchaeoLines plug-insettings and the save destination of screen shots on Windows and Linux.
-Corrected the description of "4-3. Creation of configuration file (dataset.txt)"
The following corrections due to UI changes-Added time update key (1h UP, 1h DOWN, 10min UP, 10min Down)-Change the viewpoint change key, change the camera operation-Addition of Archaeological Auxiliary Lines (ArchaeoLines) key-Corrected the description of "6-1. Date and time setting", "6-2. Move operation", and"6-3. Display switching"

0.12.1

August 23, 2021

Combined the manual and the operation manual.
Changed and Added Stellarium settings.
-Corrected the description of "3-2. Recommended display settings"-Added "3-3. Time zone setting"
The following corrections due to data file format changes-Added reference point / marker function-Added display / non-display function for reference points / markers / objects, etc.
-Supports multiple coordinate system reference points such as 19 plane rectangularcoordinates and UTM coordinate systems.
-Corresponds to the correction of the true north direction angle at the origin of thereference point to which it belongs.
-The x, y, z axis directions differ depending on the type of 3D format, and it is easy toconfuse them, so the x, y, z notation in the dataset has been changed to the E, N, H
notation.
-Added time series management to 3D models-Support for reading avatars (Unity "Humanoid" type model)-Supports marker color specification-Supports file specification including directories-Corrected the description in "4-3. Creating a configuration file (dataset.txt)"
The following corrections due to UI changes-Added the direction and altitude display of the cursor position.
-Added the function to display the latitude and longitude of the current position.
-Added the function to display the longitude / latitude of the reference point / marker andthe direction / altitude / distance from the current position (camera position).
-Zoom speed adjustment-Added a function to turn off flares such as the sun and moon when the viewing angle iszoomed to 60 degrees or more.
-Date and time InputField is now key compatible-Marker display ON / OFF-Added list of 3D objects to InfoWindow-Added a check box function to show / hide in the information window.
-Added a function to move to the reference point / marker in the information window (youcan also click the marker)-Added elevation display to the information window-Added Copy function to Information Window (Ctrl + C or Cmd + C is also possible)-Added the name display of the reference point and marker that overlaps the cursor in theinformation window.
-Added the name display of reference points, markers, remains, and 3D objects to theinformation window.
-Supports scrolling and variable size of information window-Supports display / non-display of information window-Corrected the description of "6-1. Date and time setting", "6-3. Display switching", and2

"6-4. Information display".
Bug fixes-Fixed a bug that the date and time cannot be specified in BC-Fixed a bug that the display change by the key and the icon status display are notsynchronized.
-To avoid malfunction, the key required for setting input is abolished from the shortcut
registration key.
-Fixed a bug that seconds are displayed as 1 digit in date input.
-Corrected the starting point of azimuth / altitude angle calculation in the information
window from the camera position to the human visual position.
-Corrected the starting point of elevation calculation in the information window from thecamera position to the human foot position.
-Fixed one step forward when landing from Jump or Fly mode
-Fixed that when Fly mode is canceled, it is forcibly released from the 1st viewpoint to the
3rd viewpoint.
-Fixed the phenomenon that your body can be seen from the inside when you are in the
1st viewpoint.
-Fixed a bug that the cursor moves when it overlaps with the reference point / marker whilethe viewpoint is moving.
others-Migrate 3D engine from unity2019 base to unity2021 base
-Added version notation-Multiple bug fixes and optimizations-Added "8. List of programs used in ArcAstroVR"-Added 3D model placement to Cartesian coordinates for placement height / tilt correction
to match the Earth ellipsoid.
-Adjust walking speed and running speed-Adjust the height of the steps that can be climbed-To support the operating environment with a trackpad or 1-key mouse, etc.
-Change the viewpoint change operation to left-click drag-Changed enlargement / reduction operation to Ctrl + wheel-Corrected the description of "6-2. Move operation"-Multiple optimizations
0.13.2

November 28,
2021

The following corrections due to data file format changes-Added area setting to dataset.txt to support the data format output by the QGIS plugin
terrain maker for arcAstroVR. At the same time, the setting of the down area is abolished.
-Added dataset [].rot_x, dataset [].rot_y, dataset [].rot_z as the rotation setting of 3D object.
At the same time, the setting of dataset [].rotation is abolished.
-Corrected the description of "4-3. Creation of configuration file (dataset.txt)"
others-Changed the basic height of the avatar from 180 cm to 160 cm. Collision detectionchanged to 140 cm.
-Supports pasting textures on Terrain-Addition of detailed Terrain00 (corresponding to any resolution)-Compatible with Stellarium orbit after starting arcAstroVR-Since the geoid model is now included in the terrain generation in the QGIS plugin terrainmaker for arcAstroVR, the altitude notation has been changed from altitude to ellipsoidal
height.
-When the ellipse height, EN coordinates, etc. exceed 1000 m, the display is changed to
km (two digits after the decimal point).

0.14.4

March 9, 2022

-Added auxiliary line
-Added add markers and auxiliary lines in the operation screen.
-Added move and edit markers, auxiliary lines, and objects in the operation screen.
-Added multi-language display-Added ambient light control for screens-Added selection of display coordinate system-Added vertical ascent of avatar-Added compass map-Add output of dataset.txt for various edited settings-Added game controller support-Added Head Mount Dispray support-Changed dataset.txt specification
Deleted the following descriptionarea, rp[], dataset[].rp_no, dataset[].rp_meridian, dataset[].rp_E, dataset[].rp_N,3

dataset[].rp_H, dataset[].rot_x, dataset[].rot_y, dataset[].rot_z
Added the following description
mesh, type, center, height, line[], dataset[].origin, dataset[].height, dataset[].rot_E,
dataset[].rot_N, dataset[].rot_H
The definition of rp[0], the reference point at the center of the terrain, has been
eliminated. The center point is now defined by center and height.
-Layout review to different screen sizes and resolutions; supports WXGA (1366 x 768)
screens and above.
0.15.1

May 22, 2022

-Added label display to the compass map-Added Japanese and Spanish to language settings-Added the function to save preference values and carry over the settings the next timethey are opened.
-Fixed resizing of the information window when settings are made in the various settings
dialogs.
-Fixed shifting of the compass map center and line display when moving the marker
position on the compass map screen.
-Fixed disappearance of corresponding auxiliary lines when LineEdit dialog is opened on
the compass map screen.
-Fixed disorder of information display when the designated marker of an auxiliary line isdeleted.
-Fixed auxiliary lines appearing vertically above the viewpoint when the end marker of an
auxiliary line is deleted.
-Fixed a bug that Preferences dialog could not be canceled when opened with the Info
window closed.
-Updated Unity Editor 2021.3.3f1(LTS)-Updated Input System 1.30
-Updated Localization 1.31
-Updated XR Interaction Toolkit 2.02
-Updated 3rd Person Controller + Fly Mode 2.15
-Updated TriLib2 2.16
-Updated JSON Object 2.12

0.16.1

July 25, 2022

-Added display of objects to be read when loading datasets-Added display of progress percentage when loading data sets
-Added Dome Master format output-Added setting to switch output to HMD after arcAstroVR is launched-Fixed dataset loading algorithm to Improved stability-Fixed drawing algorithm of auxiliary lines to improve uniformity of auxiliary line thickness-Fixed clipping of far distance display in HMD-Fixed an issue where the analog stick may not work on the HMD.
-Fixed problem with compass map label display width being too short and often breaking
lines-Fixed resource management to significantly reduce program size
-Update with complete migration to Unity's new InputSystem

4

1.File structure
Two apps and one dataset are required tooperate arcAstroVR•••

Stellarium app
arcAstroVR app
Dataset for arcAstroVR

1-1.Stellarium app

Fig 1：Two applications and data sets

Stellarium is a planetarium app that runs on Linux, Windows, and macOS and is provided under the
GNU General Public License and can be obtained free of charge.
Please download and obtain the latest version (Ver 0.21.0 or later) from the official Stellarium website(http://stellarium.org).
Stellarium operating requirements• OS: Linux / Unix or Windows 7 or higher or Mac OS X 10.12.0 or higher• Graphics: OpenGL 3.0 and GLSL 1.3 or OpenGL ES 2.0 behavior• Memory guidelines: 512 MB or more
• Disk procedure: 420 MB or more

1-2.arcAstroVR app
Please download the arcAstroVR app from the web site (https://arcastrovr.org/download.html?id=app)
to your PC and use it.
The arcAstroVR app is prepared for each OS.
••

For Windows : arcAstroVR-Win-0.16.1/arcAstroVR.exe
For Mac 用 : arcAstroVR-Mac-0.16.1/arcAstroVR.app

1-3.Dataset for arcAstroVR
The data set for arcAstroVR contains undulation data of land, 3D model data of buildings, and setting
information. You will need to prepare this dataset yourself. For details on creating a dataset file, pleaserefer to "4. Creating a Dataset".
Datasets that are available as samples can be downloaded from the Dataset Download page ofarcAstroVR WEB (https://arcastrovr.org/download.html?id=dataset). Please use this dataset if you
would like to simply check the operation.

5

2.Overview
ArcAstroVR is an application that displays and simulates terrain, 3D objects, markers, celestialbodies, etc. in VR space.

2-1.Functional overview
ArcAstroVR works in conjunction with the planetarium app Stellarium. Therefore, both apps need torun at the same time. arcAstroVR is in charge of spatial display of lands and buildings, movement, andoverall control, and Stellarium is in charge of calculation and display of celestial bodies.
Regarding the cooperation between arcAstroVR and Stellarium, the following communication plug-in
for Stellarium, output script, and cooperation asset for Unity created by Georg Zotti et al. Are used. In
addition, arcAstroVR is created using the VR engine Unity.
Stellarium：Remote Control (Plugin)• Authors: Florian Schaukowitsch, Georg Zotti• License: GNU GPLv2 or later※This plugin was created in the 2015 campaign of the ESA Summer of Code in Space programme.

Stellarium：Skybox Tiles (Script)• Author: Georg Zotti• License: Public Domain
Unity：Stellarim - Unity (Assets for Unity, https://unitylist.com/p/11ul/stellarium-Unity)• Author: Georg Zotti, John Fillwalk, David Rodriguez, Neil Zehr
• License: GNU General Public License v3.0
※This is a collaboration between Georg Zotti (LBI ArchPro Vienna) and John Fillwalk, David Rodriguez
and Neil Zehr (IDIA Lab, Ball State University) suggested by Bernard Frischer (Indiana University).

The cooperation between arcAstroVR and
Stellarium is as follows.
1. Send a request from arcAstroVR to
Stellarium's RemortControl plugin.
2. Stellarium Skybox script outputs 6 tiles
global image.
3. Stellarium notifies arcAstroVR of updates
through the Remort Control plugin
4. 6 Unity automatically detects the global
image output of 6 tiles, loads the global
image into Unity, and reflects it on thecelestial sphere to synthesize the image.
Fig 2：Diagram of the linkage between arcAstroVR (Unity
program) and Stellarium
Linkage diagram taken from Serious Gaming for Virtual
Archaeoastronomy （https://doi.org/10.14434/sdh.v4i1.31041）

6

2-2.Reproduction accuracy
2-2-1Terrain accuracy
In arcAstroVR, the VR space is formed by using the
shadow undulation data (raw format 16bit gray-scale
image file) divided into 9 tiles (3 rows and 3 columns)
on the base wide-area terrain. Since one tile can be
expanded to a range of 100 x 100 km*which is the specification limitof Unity, it will form a terrain of 300 x 300 km as a whole.
In addition, since shadow undulation data of up to 4097
× 4097px*specification limit of Unity can be set for one tile, it canhave a horizontal resolution of 100km ÷ 4097 = 24m in
the wide-area terrain. Also, in the height direction, 1000m to 9000m is expressed in 16bit (65536), so it canhave a vertical resolution of 10000m ÷ 65536 =15.26cm.
The data for wide-area terrain is stored in the terrain
folder of the dataset with the file names terrain11.raw ~terrain33.raw. These wide-area terrain files are arranged
as shown in Fig 3.

terrain11.raw

terrain12.raw

terrain13.raw

terrain21.raw

terrain22.raw

terrain23.raw

terrain31.raw

terrain32.raw

terrain33.raw

Fig 3：Placement of wide-area terrain files

Data for wide-area terrain must be
orthphoto-corrected, sphere-corrected,
and optical-corrected (equivalentearth-format correction) in advance(Fig. 4).

Fig 4：orthphoto-corrected, sphere-corrected, and optical-corrected(equivalent earth-format correction)

Apart from wide-area terrain with
fixed resolution and coverage, you canhave narrow-area terrain with any
resolution and variable coverage.
However, the detailed terrain can only
be 4096 x 4096px for a single tile,
with an arbitrary resolution of 1px (0.1
to 10m). 1px at 5m resolution results
in a narrow terrain with an area of4096 x 5m = 20480m.
These wide-area and narrow-area
terrain can be created with the"terrain4arcAstroVR" plug-in for the
QGIS GIS software. This plug-in canbe downloaded from the Plugin
Download page of arcAstroVR WEB(https://arcastrovr.org/download.html?
id=plugin)7

In addition to these wide-area and narrow-area
terrain, 3D models of remains (in some cases, such as
tunnels and other terrain that cannot be represented byelevation data) are superimposed and reproduced inthe VR space. The wide-area terrain and narrow-area
terrain are superimposed at the center coordinates,
which are defined as the coordinates specified bycenter in dataset.txt. The coordinates can be specified
in WGS84 (latitude and longitude) or in the plane
rectangular coordinate system (19 system) or in the
UTM coordinate system. For details on settings, referto "4-3. Creating a Settings File (dataset.txt)".
Fig 5: Overlaying of wide-area terrain, narrow-area
terrain, and 3D models

2-2-2 Accuracy of celestial bodies

Stellarium supports VSOP87 / ELP2000-82B as standard for the calculation of solar system celestialbodies, and DE430 and DE431 with higher accuracy by extension. VSOP87 guarantees accuracy of lessthan 1 ″ for Mercury, Venus, and the center of gravity of the Moon-Earth system over 4000 years before
and after 2000 AD. With the same accuracy, Jupiter and Saturn are guaranteed for 2000 years before andafter, and Uranus and Neptune are guaranteed for 6000 years before and after.
DE430 and DE431 are the lunar and planetary calendars compiled and published by NASA's JPL (Jet
Propulsion Laboratory) for planetary exploration. The DE430 is available from December 21, 1549
(Julian Day: 2287184.5) to January 25, 2650 (Julian Day 2688976.5). DE431 is compatible with August
15, 13200 (Julian Day: -0.3100015.5) to March 15, 17191 (Julian Day: 8000016.5).
Since the expression accuracy on arcAstroVR is less than the calculation accuracy of VSOP87, it is
not necessary to incorporate DE430 or DE431 (described later in 2-2-3).

2-2-3 Light and shadow accuracy
arcAstroVR displays shadows using a parallel light source (Directional Light) from the directional
altitudes of the Sun, Moon, and Venus calculated by Stellarium. Therefore, the accuracy of light andshadow depends on the calculated angle accuracy of Stellarium and the light source setting angle
accuracy of Unity.
When using VSOP87 with Stellarium, the calculated angle accuracy of Venus, Earth, and Moon is
guaranteed to be within 1 ″ (0.00028 degrees) for 4000 years before and after 2000 AD.
On the other hand, with the parallel light source setting of arcAstroVR, there is an angle accuracy of
0.001 degrees*Unity asset: Stellarium – Unity specifications. Since the accuracy of the parallel light source setting is foundto be lower than the calculated angle accuracy of VSOP87, the angle accuracy of light and shadow
depends on the parallel light source angle accuracy of arcAstroVR.
Since the rotation of the celestial sphere in diurnal motion is 15 seconds of arc per second (0.004
degrees), on arcAstro VR light and shadow are simulated with a time resolution of about 0.25 seconds
on the parallel light source angle accuracy (0.001 degrees).

83.Installation andconfiguration
3-1.Stellarium settings
After installing the latest version from theStellarium official website(http://stellarium.org), start it and configure thefollowing settings.
1 Open the setting screen (Config) [F2]>Plugins> Remote Control, and check "Loadat startup".
2 Open the setting screen (Config) [F2]>Plugins> ArchaeoLines and check "Load atstartup".
3 Restart Stellarium
4 Open the setting screen (Config) [F2]>Plugins> Remote Control, and click the"configure" key.
5 Check "Server enabled" and "Enable
automatically at startup"
6 Set 8090 for "port number"
7 Click the "Save settings as default" key toclose the settings screen.
8 Open the setting screen (Config) [F2]>Scripts> skybox.ssc, check "Close window
when script runs", and click the "▶ ︎(script
execution)" key.
9 Open Config [F2]> Tool> Screenshot and set
the following
Save destination: Path of the savelocation of the Stellarium setting file ineach*1
Format: png
Resize (check on): 960 x 910*1: For Win, specify
C:/Users/<USERNAME>/AppData/Roaming/Stellarium/
For Mac, specify/Users/<USERNAME>/Library/Application
Support/Stellarium/93-2.Recommended display settings
From the balance of visibility, it is recommended to set the following settings in the sky and viewing
option window [F4].

Sky tab• Milky Way brightness / saturation• Atmosphere visualization• Light pollution• Stars• Absolute scale• Relative scale• Twinkle

ON 1.00/1.00
ON
1
ON
2.00
1.00
OFF

SSO tab• Solar System objects• Moon’s halo
• Sun’s glare

ON
OFF
OFF

10

3-3. Time zone setting
In the Stellarium default setting, if you specify a year before 1848 (before the introduction of the timezone), the time zone of the local average solar time or the local true solar time is automatically set, so it
may be different from the time zone settingof arcAstroVR. In that case, set the timezone of dataset.txt of arcAstroVR to the
local average solar time or the time zone of
the local true sun, or set the time zone of
Stellarium to the time zone of dataset.txt.
To change the Stellarium time zone, open
your current location [F6] and turn on“Customize the time zone”, and select thedesired time zone from the "Time zone"pull-down menu.

4.Creating a dataset
4-1.Dataset file structure
The dataset consists of the following three parts:•••

dataset.txt : Dataset configuration file (required)object folder : Stores 3D objects
3D models such as archaeological sites andshadow elevation files in the vicinity are stored inthis folder. You need to prepare and create it
yourself.
terrain folder: Storage of base terrain data(required)
A total of 9 files from terrain11.raw ~ terrain33.raw are required.
In addition, it is possible to add the narrow-area terrain of terrain00.raw.

4-2. Creation of Wide-area terrain / Narrow-area terrain dataarcAstroVR can handle two types of terrain, Wide-area terrain and Narrow-area terrain.
The wide-area terrain is a 30m mesh shadow elevation data file that covers area of 300 x 300km.
Narrow-area terrain is a shadow elevation data file with any mesh resolution that covers a range of meshresolution * 4096 (20480*20480m for a 5m mesh).
Use the QGIS plug-in "terrain4arcAstroVR" that comes with this distribution to create terrain data for
arcAstroVR. Please refer to the attached "terrain4arcAstroVR.pdf" for the installation and usage of
QGIS and terrain4arcastrovr.
Store the terrain files terrain00.raw ~ terrain33.raw, terrain00.jpg ~ terrain33.jpg generated by the QGIS
plugin "terrain4arcAstroVR" in the terrain folder of the dataset.

11

4-3.Creating a configuration file (dataset.txt)
Basic information of data and installation information are described in dataset.txt.
Use the ENTRY = SETTING format, one item per line. Use # for comment out.
Each setting entry is described below.
Basic Settings• location : Title name of the data (string)• country : Country name of the data (string)• timezone : Time zone (HH:MM: -12:00 to +13:00; +0:00 if not set)
• date : Date setting at start (yyyy/mm/dd: if not set, the current time is set)
• time : Time setting at start (HH:MM:SS: If not set, the current time is set)• mesh : Set mesh resolution (enter the value set for narrow-area terrain resolution in theterrain4arcAstroVR plug-in for QGIS)• type : Set the coordinate system to be handled.(required) (WGS84, JP01~19, or UTM01~60; thetwo-digit number after JP or UTM indicates the zone number).
• center : Set the coordinates of the terrain center point.(required) (set the center coordinates in thecoordinate system set by type: longitude and latitude (°) for WGS84, Y and X coordinates (m) for
the specified zone number for JP**, and E and N coordinates (m) for the specified zone number
for UTM**).
• height : Set the height of the ellipsoid at the terrain center point (m)(required) (if the geoid height
is not included in the terrain4arcAstroVR plug-in for QGIS, set the elevation value)• avatar : Data file name of the avatar (Unity Humanoid model)
Marker Settings(The numbers in [] are marker numbers; numbers are assigned in order from 1 to the next. There is nolimit to the number of objects that can be registered.)• marker[1].name : Marker name (string)• marker[1].origin : East coordinate, North coordinate (float : degree or m) (required)• marker[1].height : Ellipsoid height (or elevation value) (float : m) (required)• marker[1].color : Color designation (hex color value)• marker[1].visible : Show/hide marker (boolean: true or false)
Auxiliary line Settings(The numbers in [] are auxiliary line numbers; numbers are assigned in order from 1 to the next. There isno limit to the number of objects that can be registered. If end_marker is specified, the line will bedrawn between start_marker and end_marker. If end_marker is not specified, a supplementary line isdrawn starting from start_marker in the direction of the angle specified in angle. Multiple angles can be
specified by separating angle with “,”.)• line[1].name : Auxiliary line name (string)• line[1].start_marker : Marker number of the starting point (integer) (required)• line[1].end_marker : Marker number of the end point (integer)• line[1].angle : Auxiliary line azimuth starting from the starting point (float : degrees; multiple
values separated by “,” are allowed)• line[1].color : Color designation (hex color value)• line[1].visible : Show/hide auxiliary line (boolean: true or false)
Object Settings(The numbers in [] are object numbers; numbers are assigned in order from 1 to the next. There is nolimit to the number of objects that can be registered.)12• dataset[1].name : Object name (string)• dataset[1].file : Object data file name (string) (required)• dataset[1].origin : East coordinate, North coordinate (float : degree or m) (required)• dataset[1].height : Ellipsoid height (or elevation value) (float : m) (required)• dataset[1].rot_E : East axis rotation at object origin (float: degrees)• dataset[1].rot_N : North axis rotation at object origin (float: degrees)• dataset[1].rot_H : Vertical axis rotation at object origin (float: degrees)• dataset[1].scale : Magnification of object (float : times)• dataset[1].start : Existence start year (integer)• dataset[1].end : Existence end year (integer)• dataset[1].visible : Show/hide object (boolean: true or false)
After completing all the settings, you can run arcAstroVR.

5.Start up
Follow the steps below to start it.
1.

Start Stellarium (For Windows, press F11
key etc. to cancel full screen)
2. Start arcAstroVR (Keep Stellarium running)
3. Click the "Select File –'dataset.txt'" key,
select the setting file "dataset.txt" for thedataset you want to read, and press "Open".

6.Operation of arcAstroVR
6-1. Date and time setting
In the date and time panel• Input Time Zone
• Enter the date (press and hold the increase/decrease key to increase/decrease at high speed)• Enter the time (you can also enter it with the slide bar)and press the update key to update the sky image of arcAstroVR.
On both sides of the slide bar, there are forward/back keys for 1 hour or 10 minutes. The forward/backkeys automatically update the sky image, so there is no need to press the update key.
You can move the date and time panel to any position you like.
* It takes about 5 seconds for 6 tiles to be output by Stellarium and reflected in arcAstroVR.
* If the sky images are not connected properly, try pressing the Update key again.

6-2. Move operation of the observer
Observer movement and display switching is done with the keyboard and mouse, or with a gamecontroller.

136-2-1. Keyboard & Mouse
Basically, drag the left mouse key to set the direction of travel, and press the "W" and "S" keys to move
forward and backward.
•
•
•

•
•
•
•

Look : Left mouse button drag (Viewpoint shifts)
Viewpoint switching : "tab" Key (Switch between 1st and 3rd person view)
Move : "W" Key (Forward to viewpoint direction)"S" Key (Backward from viewpoint direction)"A" Key (Left shift)"D" Key (Right shift)
Sprint : "Shift" Key (Press and hold to move at high speed)
Flight : "F" Key (Switches to flight mode and can fly in the direction of the viewpoint. Pressagain to return to walking mode.)
Jump / Vertical Lift : "Space" Key (Jumps when in walking mode and lifts vertically when inflight mode)
Zoom In / Out : "Ctrl" Key + "Mouse Wheel" (change viewing angle)

You can switch the display with the menu key or the keyboard.
•
•
•
•
•
•
•
•
•

Constellation Lines : Icon Click or "C" KeyConstellation Labels : Icon Click or "V" KeyConstellation Art : Icon Click or "R" Key
Equatorial Grid : Icon Click or "E" Key
Azimuthal Grid : Icon Click or "Z" Key
Cardinal Points : Icon Click or "Q" KeyAtmosphere : Icon Click or "T" KeyArchaeoLines : Icon Click or "U" Key
Planet Labels : Icon Click or "P" Key14

6-2-2. GamePad
On the GamePad, the left analog stick and left cross button are used for movement control, and the rightanalog stick is used for viewpoint shift.
•

To switch the display, press the "◯" button to enter the "display switching mode", then use theleft cross button to move to the icon you want to switch the display to, and press the "◯" button
to switch the display. (You can cancel by pressing the "×" button.)•

To change the date, press the "×" button to enter "date setting mode", use the left cross button tomove to the desired location, use the "△" and "□" buttons to adjust the value, and press the "◯"button to confirm (Update).

6-3. Display Settings
Click the "Setting" button on the top bar to configure the display settings.

6-3-1. Language
You can select the display language from the Language pulldown menu.

6-3-2. Coordinate System
From the Coordinate System pull-down menu, you can select the coordinate system to be displayed in
the Top Bar and Information Window. The coordinate systems that can be selected are as follows•••

WGS84 : It is a world coordinate system of longitude and latitude (decimal notation).
Japan PRCS : Japanese Plane Rectangular Coordinate System (System 19) (Y,X in m); zone
number (1-19) is specified in Zone.
UTM : UTM coordinate system (E,N in m notation); zone number (1-60) is specified in Zone.

6-3-3. Ambient LightYou can adjust the ambient light from the Ambient Light slide bar. In the normal setting, it is to the far
right.
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By adjusting the ambient light, the ground can be displayed even in a pitch-dark environment with nomoonlight late at night.

Fig 7: Additional Ambient Light Min

Fig 6: Additional Ambient Light Max

6-4. Top Bar and Information
Window
The position information of reference point, marker
and remains, read into arcAstroVR are displayed in
the information window.
The information window can be shown or hidden byclicking the "Show (Close) Info" key in the topbar.You can also resize the information window bydragging the resize box at the bottom right of theinformation window.

6-4-1. Display items
The display items of the top-bar are as follows.
・Type of display coordinate system
・Current longitude, north latitude, altitude(Note: Calculated from human feet position)
・Azimuth and altitude of the cursor(Note: It is calculated from the camera position)

Fig 8: Top-Bar

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The display items of the information window are as follows.
・Coordinates and ellipsoid height of the marker. Azimuth angle, elevation angle, and distance of themarker from the current position.
(Note: It is calculated from the human eye position)
・Auxiliary line start marker number, end marker number or auxiliary line azimuth angle.
・Coordinates of object origin and ellipsoid height, angle of rotation from limited, scale, start and end
year of existence

Fig 9: Information Window

6-4-2. Show/Hide
Checkboxes to the left of the Info Window control the display of marker or Auxiliary line or object.
(Note: In the case of remains/objects, even if the display check box is ON, it will not be displayed if it isa year before the existence start year or after the existence end year)

6-4-3. Add
Markers and auxiliary lines can be added by pressing the "Add"button.
The initial position of the marker will be entered where the avatar iscurrently standing. You can add a marker by entering its name,coordinates, and color, and pressing "OK".
The initial position of the auxiliary line is set to Marker number 1 andAngle 0°. It can be added by entering a name, beginning, end, andcolor, and pressing "OK.

Fig 10: Edit screen with Add and Edit
(markers and auxiliary lines)17

6-4-4. Go
The "GO" button to the right of the marker information serves as a button to move to the marker location(it is also possible to move by left-clicking on the marker on the screen).

6-4-5. Edit
The "Edit" button on the right side of Marker Information /Auxiliary Line Information / Object Information allows you to edit
the name, coordinates, color, etc. of each information.
Note that markers and auxiliary lines can be deleted by checking
the "Delete" check box and clicking the "OK" button.
(Note: There is no button to add/delete objects. If you want to add an object, please modify thedescription in the configuration file (dataset.txt) and start up again)

6-4-6. Compass Map
The "Map" button to the right of the auxiliary
line information displays a compass map
centered on the marker at the beginning of theauxiliary line.
Zooming in and out of the display area is thesame as using Zoom In / Zoom Out (orCtrl+mouse wheel with mouse / keyboard).
You can return to the normal screen by pressingthe "Close Compass Map" button in the upper
right corner of the screen.

6-4-7. Copy
The "Copy Info" button in the lower left cornerof the Info Window allows the user to retrieve
information from the Info Window to the
clipboard (Ctrl+C or Cmd+C can also be used
for copying).
The information on the clipboard is tabdelimited, and when pasted into a spreadsheet,
it is divided into cells and written.

6-4-8. Save
The "Save" button in the lower right corner of
the Information Window exports theinformation added or edited by the Add andEdit buttons as a new dataset.txt file.

6-4-9. Restore
The "Restore" button in the lower right corner of the Information Window cancels information added oredited by the Add and Edit buttons and restores the information in dataset.txt, which is read at startup.

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7. HMD（Head Mount Display）
arcAstroVR uses a Head Mount Display to provide a more immersive viewing experience with 6
degrees of freedom (6FOV). The following HMDs are supported•

Meta(Oculus) Rift / Quest / Quest2（Oculus Link Mode）

However, the PC must support OpenXR. Currently, Macs do not support OpenXR, so only Windows
is supported. Also, please note that OpenXR requires a high-performance GPU and plenty ofmemory. Please refer to the compatibility list of each HMD to see if your PC is compatible with it.

7-1. Head Mount Display (HMD) output settings
Please follow the steps below to start

1. Launch the Oculus application.（https://www.oculus.com/setup/）
2. Connect the HMD to the PC with the Oculus Link cable.
3. For Quest / Quest2, click Enable when Enable Oculus Link appears in the HMD. If Oculus Linkis already turned on, it will not appear.
4. For Quest / Quest2, click on Oculus Link from the home screen within the Head Mount Display.
5. Launch Stellarium.
6. Launch arcAstroVR and load dataset.txt.
7. Click Setting from the top bar menu of arcAstroVR to open the Settings dialog.

8. Select HMD from the Output Display pull-down.

9. Wear the HMD.

7-2. Operation with Head
Mount Display
Movement controls on the HMD follow the
GamePad control system.
*This function is in beta version and the UI for
HMD has not been implemented yet, only the
movement operation is available.

198. Dome MasterarcAstroVR supports dome master format output, enabling dome projection using a projector with afisheye lens.

8-1.Dome Master Settings
1. Click Setting from the top bar menu to open the Settings dialog.

2. Select Dome Master from the Output Display pull-down.

3. Set Pitch, Roll, FOV, and Fix according to the projector and dome shape to be projected.

Pitch

At 0°, the horizontal north direction is at the center of the dome master.
At -90°, the zenith direction is at the center of the dome master.
At 90°, the vertical down direction is at the center of the dome master.
For a 20° inclined dome, a pitch of -70 (= -90 + 20) is specified.

Roll

if the direction of the dome tilt is forward, specify 0°.
If the dome is tilted to the right, specify 90°.
If the dome is tilted to the left, specify -90°.
If the dome is sloping backward, specify 180°.

FOV

If it is a 180° hemispheric dome, specify 180°.
If it is a 200° dome, specify 200°.

Fix

If checked, the forward direction is fixed to north.
If unchecked, the avatar's direction of travel is forward.

4. To exit the Dome Master output, open the Settings dialog and select PC Display from the Output
Display pull-down.
*The UI is not dome-compatible because it is a beta version. If you want to output dome output, please hide ormove the UI so that the UI does not appear on the dome screen.

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9.Advanced display using Stellarium settings
9-1.Starry sky display settings
You can make more advanced display settings by pressing the "Sky and viewing options window" [F4]key in Stellarium. To reflect the display set in Stellarium to arcAstroVR, press [F11] Key in arcAstrVR.
•

•

•
•
•

Sky tab
You can set the brightness/saturation of the Milky Way, brightness of ecliptic light, atmosphericrefraction/absorption settings, light pollution settings, brightness of stellar displays, size of stellar
displays, and magnitude limits for stellar displays.
SSO tab
You can set the display settings for orbits, display trajectories, calculate optical line differences,
set lunar magnification, set planetary luminosity formulas, and more.
DSO tab
You can select the catalog of celestial objects to be displayed and the type of display.
Marking tab
You can select the lines to be displayed.
Starlore tab
You can select to display constellation labels, constellation lines, and constellation arts related to
cultures around the world.

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9-2. Atronomical
Calculation Window
The "Astronomical Calculation
Window" [F10] allows you to
calculate various astronomical
phenomena.
•

Ephemeris :You can search for impulses
and concealment between
two celestial bodies.

•

Eclipse :You can search for all
eclipses visible on Earth, eclipses visible at the observing location, lunar eclipses, and transits ofplanets through the sun's surface.

9-3.Other settings
The "Configuration window" [F2] allows you to change basic preferences.
•••

Main :
You can change the language settings. You can also save your display settings and preferences sothat you can start up with the same display settings next time.
Time :
You can change the date display settings and the rotation speed correction algorithm.
Tools :
You can turn on/off Topcentric coordinates and Include nutation.

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10. Licenses
arcAstroVR was released on April 1, 2022 under the GPLv3 license.

Unity built-in package•

Stellarium-unity-spout-JSONobject-U2017-3
Authors: Georg Zotti
Contact: https://github.com/Stellarium/stellarium-unity
Version: Released September 15, 2020
Licence: GNU General Public License v3.0•

3rd Person Controller + Fly Mode
Authors: Vinicius Marques
Contact: https://ricardoreis.net
Version: 2.1.5
Licence: Unity Asset Store standard EULA•

JSON Object
Authors: Defective Studios
Contact: http://defectivestudios.com/company
Version: 2.1.2
Licence: Unity Asset Store standard EULA•

Dome Tools
Authors: At-Bristol
Contact: http://at-bristol.org.uk
Version: 1.1
Licence: Unity Asset Store standard EULA•

TriLib2
Authors: Ricardo Reis
Contact: https://ricardoreis.net
Version: 2.1.0
Licence: Unity Asset Store standard EULA

Contact information
office@arcAstroVR.org

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