Questions tagged [alpha]
The alpha tag has no usage guidance.
11
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Why is it so important to minimize alpha in textures for rendering
When modeling something like a hair or foliage using textures with alpha value for offline or real-time rendering, it seems to be common practice among computer modelers to try to minimize the amount ...
- 506
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How do I add two color values containing alpha?
I started out writing my Color class as just containing R, G, B triplets. Adding colors in this situation turns out to be fairly simple.
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- 111
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In alpha premultiplied sRGB a color component can't be greater than the alpha, right?
Afaik, in alpha premultiplied color the components stored so:
[r * a, g * a, b * a, a]
So the fully opaque white color is:
...
- 711
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237
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OpenGL blending with the screen
I don't understand how OpenGL performs the blending of a texture on the screen. By default, the clear color is set to (0, 0, 0, 0). If we use the default blending equation GL_SRC_ALPHA and ...
- 269
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Given a background image B and a composie image of A OVER B, can we somehow recover image A?
I often find myself in the situation where I have some old image where I composed a translucent overlay on top of a background, but then lost (or more likely discarded) the overlay. I still have pre-...
- 113
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Repeating alpha over/under operation multiple times
I have two RGBA colors in linear [0..1] space, src and dst and I want to alpha blender src ...
- 297
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165
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Sorting my geometry for alpha testing
Here is my predicament. I am trying to draw a multitude of dots that leave trails behind them real time. Heres the difficulty, that line fades. Each dot line has a defined z position and the goal ...
- 1,445
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How to perform additive blending in Metal. What do these terms mean?
Forgive me, I dont really understand the basis of alpha blending. Like I know the formula but when it comes to the terms blending operation, source blend factor, and destination blend factor I am ...
- 1,445
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Are w3.org docs correct?
I'm referring to this section: https://www.w3.org/TR/compositing-1/#simplealphacompositing
Considering the formula co = Cs x αs + Cb x αb x (1 - αs) the docs state ...
- 113
4
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Avoid having an opaque and transparent variant of each pixel shader
Transparency can be achieved (or actually approximated) by using alpha-to-coverage (in case of MSAA) or basic alpha/transparency blending using the following approach:
Bind a rasterizer state with a ...
- 1,044
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Make Object created in a list blend in/dissolve out of a scene
I have a number of (opaque) objects created using the glGenLists() glNewList() utilities. As generated, the Alpha values are all set to 1
Is there a way to make these objects when summoned blend into ...