BlendTexture

Tips for creating and manipulating planet textures for Celestia.
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Adirondack M
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BlendTexture

Post #1by Adirondack » 04.08.2008, 22:46

Can someone tell me something about the directive 'BlendTexture' -> true | false ?

Chris? Is this obsolete?
What did it do in former versions?

Adirondack
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chris
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Re: BlendTexture

Post #2by chris » 05.08.2008, 20:42

Adirondack wrote:Can someone tell me something about the directive 'BlendTexture' -> true | false ?

Chris? Is this obsolete?
What did it do in former versions?

If set to true, the color will be combined with the texture by multiplying (or 'modulating' in OpenGL terminology.)

For example, if you have a black and white texture and specify BlendTexture true, the object will be colored with various shades of the object color. If the object color is white ([ 1 1 1 ], the default), BlendTexture will appear to have no effect. This is because you're multiplying each component of each texel by one, the identity operation.

I don't think that two many people use BlendTexture. Usually, you don't want to modify the texture color. The one place that I have seen BlendTexture used is with asteroids: the basic asteroid color is black and white, and BlendTexture true is used to tint it with the asteroid color.

--Chris

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Chuft-Captain
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Re: BlendTexture

Post #3by Chuft-Captain » 05.08.2008, 22:18

And....

I think this only works for planets, moons, asteroids ie. Celestia's built-in meshes (because other meshes such as spacecraft cannot have a color assigned.

CC
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Adirondack M
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Re: BlendTexture

Post #4by Adirondack » 07.08.2008, 10:38

chris wrote:If set to true, the color will be combined with the texture by multiplying (or 'modulating' in OpenGL terminology.)

For example, if you have a black and white texture and specify BlendTexture true, the object will be colored with various shades of the object color. If the object color is white ([ 1 1 1 ], the default), BlendTexture will appear to have no effect. This is because you're multiplying each component of each texel by one, the identity operation.
Okay, I see. Thanks.

Adirondack
We all live under the same sky, but we do not have the same horizon. (K. Adenauer)

The horizon of some people is a circle with the radius zero - and they call it their point of view. (A. Einstein)


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