2
votes
3answers
669 views

OpenGL additive blending not working as expected

I am trying to achieve additive blending with point sprites. When the sprites overlap, all I get is solid red, when I expect to get a smooth blend from red->yellow->white. My sprite texture has all ...
0
votes
1answer
272 views

Incorrect colour blending when using a pixel shader with XNA

I'm using XNA 4.0 to create a 2D game and while implementing a layer tinting pixel shader I noticed that when the texture's alpha value is anything between 1 or 0 the end result is different than ...
4
votes
1answer
213 views

Premultiplied Alpha And Alpha Testing

I have a shader that is supposed to work with either alpha blending or alpha testing, but the color values being passed in are premultiplied alpha values. Is there an easy/standard way to have it ...
1
vote
1answer
245 views

Why can't a blendShader sample anything but the current coordinate of the background image?

In Flash, you can set a DisplayObject's blendShader property to a pixel shader (flash.shaders.Shader class). The mechanism is nice, because Flash automatically provides your Shader with two input ...