I am currently working on writing a shader for combination lighting. The idea behind it is to apply directional light, point light, and spot light in a single pass. I believe I can do this by:
- Calculate the color after directional light is applied.
- Calculate the color after the point light is applied.
- Calculate the color after the spot light is applied.
- Return the final color of the pixel.
I believe this will allow me to have multiple point and spot lights that effect the pixel currently being handled by the pixel shader.
I believe the math for this will be:
return directional + pointLight + spot;
However, my concern is that this will create just a solid white object and I am unsure as to how to prevent that. Maybe each portion is normalized to a specific percentage of full intensity and the result would be:
directional = calcDirectional() * 0.3f; pointLight = calcPoint() * 0.3f; spot = calcSpot() * 0.3f; return direction + pointLight + spot;
But again, I am not 100% sure on this.
What is the proper way to additively calculate colors in this scenario?