Rendered by Lana Pinskaya
So I said... That sounds like a cool thing, Id like to finish it off. A few weeks passed, and I said to myself there ought to be something like this already... but I found little that seemed like what I wanted... I did find OpenUniverse.org and it was good... Very good... But I couldnt figure out how to get it to render what I wanted, and the screen saver edition seemed buggy... So I had this wireframe code, a little real data, after fooling with it for a week, I was able to come up with a reasonably satisfactory simulation with solid spheres.
Then I thought... It would be cool if I could get texture mapping to work... I already had the texture maps from OpenUniverse. Getting that to work proved to be much tougher... I couldnt figure it out with documentation on the internet... I looked at the OpenUniverse source, and it was just too much to be able to figure anything out from, so I kept looking on the Internet until I found the website of Richard S. Wright, Jr. He had written a book titled OpenGL SuperBible... I looked at what he had online, and it was EXACTLY what I thought I needed, In fact I was so impressed, I bought the book within 24 hours of finding his website. A bit more work, and I got the texture maps working... then I made it into a screen saver.
Now it was quite obvious to me that ACTUAL SIZE wouldn't be very entertaining... so I put a lot of effort trying to figure out the optimum distortion of the size of the planets to the size of their orbits. It occurred to me that a user might not prefer my selection, so I came up with a sliding distortion algorithm, and made it user selectable... So now it has a Settings panel, then it seemed like one setting after another got moved from being hard coded to the Settings panel.
This software is a Visualization Toy, it is based on as much real data
and real mathematics as I can obtain and understand, but it does allow you to distort
the facts so that it can be a useful visualization tool. If you want a similar product
without distortions, visit http://www.openuniverse.org Its a very
good package, with a different purpose... it has now been superceded by Celestia which is a most excellent package indeed! Also
of interest may be J-Track 3D
Get more, newer, or higher resolution maps at: http://maps.jpl.nasa.gov/ ...Or click on the download button to get a large variety of planetary images.
The addition of the stars and asteroids have helped to improve the sense of dimension. The star database contains 118 thousand stars from the Hipparcos star catalog. The asteroid database contains the 6 thousand largest asteroids listed by Edward Bowell of Lowell University, each with its correct size and orbit computed. Currently I'm working on adding comets to the program.
If you have a request, suggestion or information that would improve the simulation, drop me a note at firstname.lastname@example.org.
This is a public distribution please feel free to distribute this as widely as possible... Hurry while it's still free!
R Zoom on Planets
If selected, the camera will focus on individual planets otherwise, the Sun will continuously be the focus of the camera.
Will cause the camera to focus on the planets in a random order. (Only applies if Zoom on Planets is selected)
Will cause the camera to focus on the planets in order from the sun i.e.: Sol, Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, Neptune and finally Pluto, before it returns to Sol and repeats the order. (Only applies if Zoom on Planets is selected)
Will maintain the camera focus on the specific planet listed in the DropDownBox. (Only applies if Zoom on Planets is selected)
Planet choice DropDown
Selects the planet that will have the camera's focus. (Only applies if Specific is selected)
QuickAdvance vs SlowAdvance
Selects the speed that the camera approaches the bodies.
Fast Orbit vs Slow Orbit
Selects the speed that the camera rotates around the focus. This rotation is independent of the orbits of the planets, but can create the illusion that the planets are orbiting faster than they actually are. A setting of Fast Orbit could cause dizziness.
Near Periapsis vs Far Periapsis
The Periapsis of the Camera's orbit is the point at which it approaches nearest to the body (sun or planet). A setting toward the Near Periapsis will go very close to the planet. (the Periapsis, can not be set further than the Apoapsis)
Near Apoapsis vs Far Apoapsis
The Apoapsis of the Camera's orbit is the point at which it is furthest from the body (sun or planet). A setting toward the Far Apoapsis will go very far from the planet, to view the whole solar system, when the camera has fully retreated. (the Apoapsis, can not be set nearer than the Periapsis)
R Show Legend
This choice will display a Legend showing information about the body in focus.
Font Size DropDown
This controls the Font size of the Legend (if it is enabled by the Show Legend option)
Small Bodies vs Large Bodies
Sets the size of the planetary bodies, Small Bodies renders the planets at the small sizes that most accurately represents their true sizes. Large Bodies can be selected to magnify the size of each planet, and render more detail.
Normal Ratio vs Log Ratio
Controls the relative size of each planetary body to the others, at Normal Ratio, the relative sizes will be acurate, at LogRatio, the sizes of the planets will be closer to the each other, but the largest will still be larger than the smallest.
Fast Rotation vs Normal
This control affects the speed at which the planets rotate around their own axis. If Planet Normal Rotation Speed and Orbit Speed Normal are both set, then the rotation and orbits will be correct relative to each other.
Octahedron vs Sphere
This control is primarily to affect the speed that the video card can draw the planets. A choice near Octahedron will render the planets with very few sides, while a choice near Sphere will render the planets with very many sizes. This choice provides a way to trade off computer performance versus visual clarity.
R Draw Minor Rings
If this control is selected, a the rings of Jupiter, Neptune and Uranus will be rendered.
Actual Size vs Distort Orbits
Actual Size attempts to show the orbits at their correct relative sizes. Distort Orbits shows the orbits as if they were all equally spaced. Note: As the Planetary body size increases, the Orbits are distorted in order to accommodate the size of the Planet, so that if the Planet sizes are not set to Small Bodies, then some distortion will always occur regardless of this setting.
Fast vs Normal
Controls the speed at which the planets travel around the sun. If Planet Normal Rotation Speed and Orbit Speed Normal are both set, then the rotation and orbit speeds will be correct relative to each other.
Dim vs Bright
Controls how bright the Celestial Grid, Orbital lines and Clock Hands are drawn.
Normal vs Eccentric
At normal, the orbits will be near perfect circles as they are in reality the slider can be set toward Eccentric to exaggerate the Eccentricity of the orbits. The Eccentricity will also exaggerate the speed of travel along the orbit, with the planets traveling faster at their closest approach to the Sun. This can result in the more eccentric orbits crossing orbits that they do not actually cross.
R Clock Hands
Draws lines from the sun to each planet may be helpful when Small Bodies is selected.
If this control is selected, a wireframe will be rendered around the planet, if the computer is slow, this setting can be chosen instead of Sold. Wireframes also include axis, so that the rotations of a body can most clearly be observed. (wireframes are rendered slightly larger than the planet, in case both solids and wireframe are rendered)
If this control is selected, a the planetary bodies will be rendered as lighted solid objects, if the computer is slow, this setting may not be desireable.
R Texture Maps
If this control is selected, a map of each planet (commonly called a texture map) will be rendered on the solid bodies. This will produce the most desired effects. (Only applies if Solid is selected)
In Dir: [Text Box]
The directory specified in this text box specifies the directory where the program will try to find the texture maps, normally this is set to C:\windows\3dsolar\bmp but can be set to any directory. (the program can only use BMP format images, you may provide your own images or use the images provided with the program.)
Number of Asteroids
This controls the number of Asteroids drawn. A setting toward Many Asteroids will draw the 6000 largest asteroids. When the program begins, it will not have calculated the orbits of the asteroids, asteroids are added to the rendering as their orbits are calculated. The ideal setting for this control will depend both on individual preference, and computer performance.
Number of Stars
Controls the number of stars rendered by the program. A setting toward Many Stars will draw the complete database of 118,000 stars. The ideal setting for this control will depend both on individual preference, and computer performance.
Shows the Celestial Lattitude and Longitudes.
FreezeFrame vs Full Motion (only for Screen Saver)
Freeze Frame will hold each image for a full second. Full Motion, will attempt to display 60 frames per second (actual performance will depend on the individual computer). Smooth animation will be achieved between 15 and 30 frames per second. The bottom left corner displays the frame rate in Frames Per Second.
Opens a list of settings and commands.
The most accurate display can be achieved by setting:
Planets: Small Bodies, Normal Ratio, Normal Rotation; Orbits: Actual
Size, Normal, Eccentricity Normal. However this display is generally
not helpful for visualizing the Solar System. The most entertaining display is not
the most accurate.