Something like HDR

This is not real HDR because input scene is stored in a PF_FLOAT_A8R8G8B8 buffer not a PF_FLOAT16_RGBA. With my deferred shading system it should be possible because the first MRT buffer is a floating point one (storing diffuse in RGB and specular in A) and the light pass exceed 1.0f - but if the HDR compositor tries to use a floating buffer as input it shows artifacts and doesn't render the sky

With hdrExposure set to 1.5f.

With hdrExposure set to 2.0f: