I've encountered a bizzare problem-if I use a non-blurred normal map to make fullscreen distortion I get low fps-but if I use a blurred texture (both are the same size) I don't get low fps???
Here is the hlsl code that offsets the UV coords based on the distortion (I must warn you that I am a beginner so I didn't look up at how "the pros" do this, but I think this is more or less it(?) )
// This will hold the UV offset once it will be retrived from the distortion texture
float2 uvOffset;
// Distortion multiplier
float offsetPower=0.1f;
// Here the distortion is retrived from the texture
float4 uvOffPower=2.0f*distMap.Sample(sampler1,input.texcoord)-1.0f;
// Distortion is scaled down a bit
uvOffPower*=offsetPower;
// Here the final UV coords are comuputed by adding the distortion to the original texcoords
uvOffset=float2(uvOffPower[0],uvOffPower[1])+input.texcoord;
Here is the image I use (if the entire image is like the left part I get low fps, but not if it is like the right part)
Why??
Why??
