I want to do additive blending using GLSL. With fixed pipeline I would use:
glEnable(GL_BLEND);
glBlendFunc(GL_ONE, GL_ONE);
drawStuff()
Is there any way to do this with GLSL? I tried using:
gl_FragColor += colorToAdd;
doesn’t produce correct results (I guess gl_FragColor doesn’t contain the current framebuffer color). Is it possible to do this blending in a shader?