Planet - Revision history

Redmaw: Updated descriptions and added example images.

2021-12-24T08:47:55Z

Updated descriptions and added example images.

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Matt: Added a zero to radius of Uranus

2013-08-13T03:14:48Z

Added a zero to radius of Uranus

Jo at 05:02, 18 October 2012

2012-10-18T05:02:01Z

Jo at 04:57, 18 October 2012

2012-10-18T04:57:42Z

Jo at 04:48, 18 October 2012

2012-10-18T04:48:36Z

Jo at 04:30, 18 October 2012

2012-10-18T04:30:16Z

Jo at 04:28, 18 October 2012

2012-10-18T04:28:40Z

Jo at 04:25, 18 October 2012

2012-10-18T04:25:34Z

Jo at 04:25, 18 October 2012

2012-10-18T04:25:09Z

JavaJones at 23:00, 3 June 2012

2012-06-03T23:00:59Z

@@ Line 19: / Line 19: @@
 * Jupiter: 71490000 m
 * Saturn: 60268000 m
-* Uranus: 2559000 m
+* Uranus: 25590000 m
 * Neptune: 25629000 m
 * Pluto: 1160000 m

@@ Line 26: / Line 26: @@
 If you want to change the size of the planet then you need to understand how the scene origin and the planet '''Centre''' and '''Radius''' are related to each other. As described above we typically want the scene origin to be at the North Pole of the planet. Let's say we want a (small!) planet that has a radius of 5000m. If you created a new planet and set its '''Centre''' to the scene origin (0, 0, 0) and '''Radius''' to 5000 then the North Pole would end up being 5000m away from the origin. See Example A in the image below.
-To place the origin at the North Pole we need to offset the position of the planet. It's very easy to do this. Simply set the the Y coordinate of the '''Centre''' parameter to the same value as the '''Radius''' but make the value negative. For example we would set the Y coordinate to -5000. Set the X and Z coordinates to 0. This moves the planet "downwards" along the Y axis and aligns the scene origin with the planet surface at the North Pole. Example B in the image below shows what this looks like. You can see how the scene origin is now at the surface of the moved planet.
+To place the origin at the North Pole we need to offset the position of the planet. It's very easy to do this. Simply set the the Y coordinate of the '''Centre''' parameter to the same value as the '''Radius''' but make the value negative. Going with our current example we would set the Y coordinate to -5000. Set the X and Z coordinates to 0. This moves the planet "downwards" along the Y axis and aligns the scene origin with the planet surface at the North Pole. Example B in the image below shows what this looks like. You can see how the scene origin is now at the surface of the moved planet.
 [[Image:Planet-radius-origin.png|center|Diagrams showing how scene origin and Planet Radius and Centre relate to each other]]

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-[[Image:drex_module_193_image_0.png|485pxpx|Planet]]
+[[Image:drex_module_193_image_0.png|center|Planet]]
 '''Node Description and Purpose:'''<br />
@@ Line 27: / Line 27: @@
 To place the origin at the North Pole we need to offset the position of the planet. It's very easy to do this. Simply set the the Y coordinate of the '''Centre''' parameter to the same value as the '''Radius''' but make the value negative. For example we would set the Y coordinate to -5000. Set the X and Z coordinates to 0. This moves the planet "downwards" along the Y axis and aligns the scene origin with the planet surface at the North Pole. Example B in the image below shows what this looks like. You can see how the scene origin is now at the surface of the moved planet.
 If you want to change the radius of the default planet then the easiest way to do it is set the '''Radius''' parameter to the new radius. Now copy and paste that value into the '''Centre''' Y coordinate and make it negative.
 <br />

@@ Line 26: / Line 26: @@
 If you want to change the size of the planet then you need to understand how the scene origin and the planet '''Centre''' and '''Radius''' are related to each other. As described above we typically want the scene origin to be at the North Pole of the planet. Let's say we want a (small!) planet that has a radius of 5000m. If you created a new planet and set its '''Centre''' to the scene origin (0, 0, 0) and '''Radius''' to 5000 then the North Pole would end up being 5000m away from the origin. See Example A in the image below.
-To place the origin at the North Pole we need to offset the position of the planet. It's very easy to do this. Simply set the the Y coordinate of the '''Centre''' parameter to the same value as the '''Radius''' but make the value negative. For example we would set the Y coordinate to -5000. Set the X and Z coordinates to 0. This moves the planet "downwards" along the Y axis and aligns the scene origin with the planet surface at the North Pole. Example B in the image below shows what this looks like.
+To place the origin at the North Pole we need to offset the position of the planet. It's very easy to do this. Simply set the the Y coordinate of the '''Centre''' parameter to the same value as the '''Radius''' but make the value negative. For example we would set the Y coordinate to -5000. Set the X and Z coordinates to 0. This moves the planet "downwards" along the Y axis and aligns the scene origin with the planet surface at the North Pole. Example B in the image below shows what this looks like. You can see how the scene origin is now at the surface of the moved planet.
 If you want to change the radius of the default planet then the easiest way to do it is set the '''Radius''' parameter to the new radius. Now copy and paste that value into the '''Centre''' Y coordinate and make it negative.

@@ Line 9: / Line 9: @@
 To help with this if you're using georeferenced data you can set the latitude and longitude of the planet origin. This effectively shifts the planet origin to the scene origin where accuracy is better. It's a bit like the whole planet spins round so that the area you're interested ends up at the North Pole.
 You can have multiple planets in a scene. For example to create a moon you can make a new Planet object and position and size it appropriately. Here are some sizes of planets etc. in our solar system:
@@ Line 28: / Line 22: @@
 * Neptune: 25629000 m
 * Pluto: 1160000 m
 <br />

@@ Line 10: / Line 10: @@
 To help with this if you're using georeferenced data you can set the latitude and longitude of the planet origin. This effectively shifts the planet origin to the scene origin where accuracy is better. It's a bit like the whole planet spins round so that the area you're interested ends up at the North Pole.
-If you want to change the size of the planet then you need to understand how the scene origin and the planet '''Centre"" and '''Radius''' are related to each other. As described above we typically want the scene origin to be at the North Pole of the planet. Let's say we have a (small!) planet that has a radius of 5000m. If you created a new planet planet and set its '''Centre''' to the scene origin (0, 0, 0) and '''Radius''' to 5000 then the North Pole would end up being 5000m away from the origin. See Example A in the image below.
+If you want to change the size of the planet then you need to understand how the scene origin and the planet '''Centre''' and '''Radius''' are related to each other. As described above we typically want the scene origin to be at the North Pole of the planet. Let's say we have a (small!) planet that has a radius of 5000m. If you created a new planet planet and set its '''Centre''' to the scene origin (0, 0, 0) and '''Radius''' to 5000 then the North Pole would end up being 5000m away from the origin. See Example A in the image below.
 To place the origin at the North Pole we need to offset the position of the planet. It's very easy to do this. Simply set the the Y coordinate of the '''Centre''' parameter to the same value as the '''Radius''' but make the value negative. For example we would set the Y coordinate to -5000. Set the X and Z coordinates to 0. This moves the planet "downwards" along the Y axis and aligns the scene origin with the planet surface at the North Pole. Example B in the image below shows what this looks like.

@@ Line 4: / Line 4: @@
 The Planet object is the basis for most scenes in TG2. It is the terrain surface and the atmosphere is created around it. New Planet nodes are initially created with a default [[Power Fractal Shader v3]] surface shader and an [[Planet Atmosphere]] node inside their internal node networks.
-TG2 can handle zooming into a planet from way out in "space" to very close to the planet surface. However if the scene you're creating is on a kind of local scale rather than planetary scale we recommend that you create the scene around the origin of the planet, which is effectively the North Pole. As you move a long way from the origin coordinates begin to lose accuracy and you might start to see things you're not expecting. In many cases this isn't a problem and creating the scene close to the origin works well.
+TG2 can handle zooming into a planet from way out in "space" to very close to the planet surface. However if the scene you're creating is on a kind of local scale rather than planetary scale we recommend that you create the scene around the origin of the planet, which is effectively the North Pole by default. As you move a long way from the origin coordinates begin to lose accuracy and you might start to see things you're not expecting. In many cases this isn't a problem and creating the scene close to the origin works well.
 It does however mean that even though TG2 can model whole planets if you want to model a real world location it isn't necessarily a good idea to put that location in the same location as it is in the real world. For example let's say you wanted to model an area in the South Island of New Zealand. If you used the real position on the planet, low down in the Southern Hemisphere, you would likely find problems with coordinate accuracy. It would be much better to reposition the location at the North Pole.
-To help with this if you're using georeferenced data you can set the latitude and longitude of the planet origin. This effectively remaps that position to the planet origin where accuracy is better.
+To help with this if you're using georeferenced data you can set the latitude and longitude of the planet origin. This effectively shifts the planet origin to the scene origin where accuracy is better. It's a bit like the whole planet spins round so that the area you're interested ends up at the North Pole.
 You can have multiple planets in a scene. For example to create a moon you can make a new Planet object and position and size it appropriately. Here are some sizes of planets etc. in our solar system: