I need some help with OpenGL textures masking. I have it working but need to find some other blending function parameters to work in other way. Now I have
//Background
...code...
glBlendFunc(GL_ONE, GL_ZERO);
...code
//Mask
...code...
glBlendFuncSeparate(GL_ZERO, GL_ONE, GL_DST_COLOR, GL_ZERO);
...code...
//Foreground
...code
glBlendFunc(GL_DST_ALPHA, GL_ONE_MINUS_DST_ALPHA);
...code
Now it sets foreground’s opacity to 0 (fills with background texture) where mask is transparent. I need it to react to mask’s colors. I mean something like setting foregrounds opacity depending on mask’s color. For example if mask is black (0.0,0.0,0.0) then the opacity of that place in foreground is 0 (is filled with background), and if mask is white (1.0,1.0,1.0) then the opacity of foreground is 1 (not filled with background). It can be in reverse consequence (white = opacity 0, black = opacity 1). I just need it to work depending on color.
Visualization:
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[li]1st column is my current result. Circle in mask is transparent.[/li][li]2nd column is example of result I am trying to get. Circle in mask is white.[/li][li]3rd column is example of why I want to get it working just like as I said (white mask color = foreground alpha 0, black mask color = foreground alpha 1 or reverse)[/li][/ol]|
|[ol]
[li]1st row is background[/li][li]2nd row is mask[/li][li]3rd row is foreground[/li][li]4th row is result[/li][/ol]||