Alpha mask texture

[Rick]

Is there a shader that allows you to have a mask texture? Not a diffuse that has alpha but a separate texture from the diffuse that is b&w that shows where the alpha should be?

[tjheldna]

Look at the campfire texture in urWorld Project. It uses a b/w mask texture to define the ember glow areas. It's not exactly what your after but it's close and you may be able to rework it.

[macklebee]

There have been several shaders that use masks (in various capacities) - found within 5 minutes of searching for the keyword "mask".

I also remember shadmar having several posts in the past where he was using masks for 2D effects as well.

[GorzenDev]

this could easily be achieved by adding 3 lines of code to any diffuse shader you can find in LE.
for shadows you add the same lines of code in any shadow shader.

//In the Fragment stage of the shader add to //Uniforms
//You can use any texture slot you like
//I used 4 since 1 till 3 are diffuse,normal,specular
uniform sampler2D texture4;//Black and White map


//In the void main(void) method add somewhere at the top
vec4 alphamask = texture(texture4,ex_texcoords0);
//Check for pure black color and discard
if (alphamask.r == 0.0 && alphamask.g == 0.0 && alphamask.b == 0.0) discard;

NOTE: make sure the Vertex stage of the shader passes ex_texcoords0 to the Fragment stage but any diffuse+alphamask shader does this.