Aloha fellohas!
Is it possible to change normal for entire scene perhaps using Postprocess somehow?
Like what math happens between normal and diffuse to give the final result? Perhaps we can use that somehow to pipe the changes to normal
Alternately, Is it possible to change world normal for global changes?
Thanks!
T
It depends on the shading model. A very simple example would be that normal vectors are compared to each light vector in range of that pixel using a dot product operation. This tells that pixel how much light it should receive. This is multiplied by the color and strength of the light. The process is repeated for every relevant light source, with each result being added to the last.
This would only solve direct lighting. Additional work would need to be done to add indirect lighting aka global illumination into the scene.
You can change a materials normals in the material itself. The post-process is too late. Perhaps if you explain what effect you’re trying to achieve, we can point you in the right direction without having to rewrite a lighting model from scratch.