You might be interested in having a look at ShaderGen. From the description: ShaderGen is a program that can automatically produce shaders that mimic the results of a set of fixed function state. This tool was used to verify the fixed function shader code that is described in Chapter 9. By the way, you will … Read more
Lambertian reflectance model To model the reflection of light in computer graphics is used a Bidirectional reflectance distribution function (BRDF). BRDF is a function that gives the relation between the light reflected along an outgoing direction and the light incident from an incoming direction. A perfect diffuse surface has a BRDF that has the same … Read more
My bet is on the color setting/mixing in fragment shader… you are setting output color more then once If I remember correctly on some gfx drivers that do a big problems for example everything after the line color = vec4(brownColor * (texture(diffuseMap, fsCoords).rgb + 0.25), 1.0);//add a fixed base color (0.25), because its dark as … Read more