Panoramas are pictures which surround you, giving you the impression that you are there. Since they're only pictures, they may be easier to make than full 3D models of a location.
Panoramic images only look right if your viewpoint is at a specific position, usually at the center. You can look in all directions without distrubing the illusion. If you move away from that position, however, then all the proportions of the projected image become distorted.
Three of the panoramic projections that are used quite often are spherical, cylindrical and cubical.
Most VRML programs are used only to display panoramic images. The 3D objects below make it easy to view panoramas within Celestia.
After you've gone to the center of a panorama within Celestia, here's how you can enable the "Alt-Az" arrow key mode so that you can turn your viewpoint appropriately.
Alternatively, you can put your computer's numeric keypad into "numeric lock" mode and then use the 4 and 6 keys to rotate to the left and right.
Archive: TOT-PANORAMA-V3.ZIP Length Date Time Name -------- ---- ---- ---- 0 05-11-06 13:23 tot-panorama-v3/models/ 1870085 04-29-06 15:55 tot-panorama-v3/models/surface.cmod 2718 04-29-06 10:45 tot-panorama-v3/models/tot-cyl-pano-an8.3ds 413 04-29-06 15:58 tot-panorama-v3/models/tot-topo.cmod 0 05-11-06 13:23 tot-panorama-v3/textures/ 0 05-11-06 13:23 tot-panorama-v3/textures/hires/ 1398280 05-07-06 14:32 tot-panorama-v3/textures/hires/tot-cyl-pano.dds 0 05-11-06 13:23 tot-panorama-v3/textures/lores/ 367845 04-30-06 17:59 tot-panorama-v3/textures/lores/tot-cyl-pano.jpg 0 05-11-06 13:23 tot-panorama-v3/textures/medres/ 1173018 04-29-06 13:02 tot-panorama-v3/textures/medres/big-tot-topo.jpg 20992 05-11-06 06:42 tot-panorama-v3/textures/medres/Thumbs.db 699208 05-07-06 14:35 tot-panorama-v3/textures/medres/tot-cyl-pano.dds 1242909 04-29-06 11:07 tot-panorama-v3/textures/medres/tot-topo.jpg 1837 05-12-06 09:17 tot-panorama-v3/tot.html 1708 05-12-06 09:13 tot-panorama-v3/tot.ssc 2610 05-12-06 09:23 tot-panorama-v3/tot-readme.txt -------- ------- 6781623 17 files
Spherical panoramas are projected onto the inside of a sphere.
Flat images that cover the entire spherical viewing angle (four π steradians) around the observer are produced in any of a variety of projections. Hammer-Aitoff seems to be the most common, although many are available as "simple cylindrical."
Spherical panoramas often are created by astronomers to display all-sky maps.
An image must be in "simple cylindrical" format for use with this model. This is the same projection format as is used for surface texture maps that are placed on the outside of planetary bodies within Celestia.
Software that does a good job of converting Hammer-Aitoff images into simple cylindrical is hard to find. Iris by Christian Buil is one such utility, but it has some problems: I've found it very difficult to avoid a pole-to-pole seam.
For more details, see the file sphere-pano/readme.txt
within the Zip
archive.
Cylindrical panoramas are projected onto the inside of a cylinder. An image to be used as a cylindrical panorama should show 360 degrees around the observer, but there's no standardized height. Usually they've been constructed from many pictures taken in a circle around the viewpoint.
Cylindrical panoramas often are created by photographers. There's a large variety of software available to stitch photographs together into cylindrical panoramas.
The easiest way to place a cylindrical panorama within Celestia is to project it onto the same spherical 3D model as is described in section 1 above. Scale the panoramic image if necessary, and pad its top and bottom to make its dimensions (in pixels) a power of two on a side. There may be some mild distortion of the perspective near the top and bottom of the resulting image, but it's usually not noticable.
For more details, see the file sphere-pano/readme.txt
within the Zip
archive.
A sample cylindrical panorama is included in the Zip archive above. Here's a screenshot showing it being used within Celestia. It's an anaglyph (red/blue) 3D panorama of Columbia Memorial Station recently taken by the Spirit excursion vehicle on Mars.
![]() Columbia Memorial Station in 3D |
Here's a Cel:// URL to take you to this viewpoint.
Columbia Memorial Station |
Alternatively, one can use a 3D modelling program to construct a cylinder with the proportions required by the particular panoramic image. An advantage of this approach is that the surface texture image only has to contain the panorama itself, without empty borders. Here's an example where this has been done.
It displays the veiw from the peak of the mountain known as "The Tooth of Time" on Philmont Scout Ranch.
![]() Tooth of Time on Philmont Scout Ranch |
Here's a Cel:// URL to take you to this viewpoint.
Tooth of Time |
![]() Tooth of Time Ridge (DEM) |
Here's a Cel:// URL to take you to this viewpoint.
Tooth of Time Ridge (DEM) |
![]() Philmont topogoraphy (a work in progress) |
![]() Philmont: Baldy Mountain topogoraphy (a work in progress) |
|
Provides a panoramic view of the Tooth of Time and 3D topographic
display of the Tooth of Time Ridge. v3 makes it easier to view
higher resolution images of the panorama if your graphics card supports
them.
To learn how to install Celestia and to look at this panorama, please visit the Web page novice-panorama.html. |
The panoramic photograph of the Tooth of Time was provided by Julian Love, BSA Troop 116, Mecklenburg County Council (Charlotte, NC) and is used with his permission. The topographical maps were created by the USGS. The 3D models were created by s.ball. See also: Selden's Philmont page.
Archive: TOT-PANORAMA-V3.ZIP Length Date Time Name -------- ---- ---- ---- 0 05-11-06 13:23 tot-panorama-v3/models/ 1870085 04-29-06 15:55 tot-panorama-v3/models/surface.cmod 2718 04-29-06 10:45 tot-panorama-v3/models/tot-cyl-pano-an8.3ds 413 04-29-06 15:58 tot-panorama-v3/models/tot-topo.cmod 0 05-11-06 13:23 tot-panorama-v3/textures/ 0 05-11-06 13:23 tot-panorama-v3/textures/hires/ 1398280 05-07-06 14:32 tot-panorama-v3/textures/hires/tot-cyl-pano.dds 0 05-11-06 13:23 tot-panorama-v3/textures/lores/ 367845 04-30-06 17:59 tot-panorama-v3/textures/lores/tot-cyl-pano.jpg 0 05-11-06 13:23 tot-panorama-v3/textures/medres/ 1173018 04-29-06 13:02 tot-panorama-v3/textures/medres/big-tot-topo.jpg 20992 05-11-06 06:42 tot-panorama-v3/textures/medres/Thumbs.db 699208 05-07-06 14:35 tot-panorama-v3/textures/medres/tot-cyl-pano.dds 1242909 04-29-06 11:07 tot-panorama-v3/textures/medres/tot-topo.jpg 1837 05-12-06 09:17 tot-panorama-v3/tot.html 1708 05-12-06 09:13 tot-panorama-v3/tot.ssc 2610 05-12-06 09:23 tot-panorama-v3/tot-readme.txt -------- ------- 6781623 17 files
Cubical panoramas consist of 6 square pictures, each covering about 90 degrees. Four of them combine to display the horizon around the observer, one shows the view above, and the sixth shows what's below the viewpoint.
Cubical panoramas often are created using programs like Terragen.
Two types of cubic bodies are available here. The first projects a single image, applying different parts of it onto the different faces of a cube. The other projects six separate images, one onto each face.
For proper positioning within Celestia, the north pole of the cubes is at the center of the "top" face, tile #5, while the prime meridian passes vertically through the center of tile #1.
The design of this 4x2-cube model is primarily the work of Grant Hutchison. He eliminated the seams at the edges. I'd been unable to get rid of them.
The 3DS model "4x2-cube" requires a single surface texture image file composed of 8 tiles. Six of those tiles are projected onto the six sides of the cube. They should be arranged in a specific pattern (see fig 1 below). The other two tiles are ignored. They can contain anything you want -- information about the other pictures, for example.
The 3DS model "4x2-cube" produces what appears to be a seamless panorama. This is at the cost of losing a few pixels around the edges of each of the tiles. If you look very closely, you may be able to see this.
For more details, see the file 4x2-cube/readme.txt
within the Zip
archive.
The 3DS model "6-cube" requires six separate surface texture image files. One is projected onto each of the faces of the cube.
Unlike the original version, v2 of the 3DS model "6-cube" produces a panorama with no visible seams. In order to do this, the model definition specifies that the area of the textures used by the cube is to start 1/1000 of the way in from the edges of those textures. This tiny offset seems to compensate exactly for the excess texture area that is visible along the edges of the cube. The seams in the previous version of 6-cube were due to the edges of other texture images being visible.
For more information, see the file 6-cube/readme.txt
within the Zip
archive.
A sample cubical panorama is included in the Zip archive above. Here's a screenshot showing it being used within Celestia. It shows a tropical beach somewhere in the South Pacific. This panorama, ©2003 by Andrew Tribick, was created using Terragen.
![]() A Tropical Beach within Celestia |
Here's a Cel:// URL to take you to this viewpoint.
Tropical Beach |
The procedure for aligning panoramas properly and so they'll stay in the correct position on the surface of a planet may not be immediately obvious. The "place" .SSC catalog files included in these Addons provide a model for doing this correctly.
The background for this procedure is described on the Web page Placing objects at defined locations on planetary surfaces by Grant Hutchison. Grant also has provided a spreadsheet to help in calculating the right panorama orientation values.
If you don't tell me that something's missing, unclear or wrong, I can't improve it.