I'm having some issues with specular lights, to be more specific, the specular color seems to be flickering when I set high power, like 512 (I set the specular color to green, so you can see better):
http://i.imgur.com/PY0cmJA.gif
And when a power like 32 is used, everything seems ok:
Pixel shader hlsl:
pin.NormalW = normalize(pin.NormalW);
float3 toEyeW = normalize(gEyePosW - pin.PosW);
// Start with a sum of zero.
float4 ambient = float4(0.0f, 0.0f, 0.0f, 0.0f);
float4 diffuse = float4(0.0f, 0.0f, 0.0f, 0.0f);
float4 spec = float4(0.0f, 0.0f, 0.0f, 0.0f);
// Sum the light contribution from each light source
float4 A, D, S;
ComputeDirectionalLight(gMaterial, gDirLight, pin.NormalW, toEyeW, A, D, S);
ambient += A;
diffuse += D;
spec += S;
float4 litColor = ambient + diffuse + spec;
litColor.a = gMaterial.Diffuse.a;
return litColor;
ComputeDirectionalLight function:
void ComputeDirectionalLight(Material mat, DirectionalLight L,
float3 normal, float3 toEye,
out float4 ambient,
out float4 diffuse,
out float4 spec)
{
// Initialize outputs.
ambient = float4(0.0f, 0.0f, 0.0f, 0.0f);
diffuse = float4(0.0f, 0.0f, 0.0f, 0.0f);
spec = float4(0.0f, 0.0f, 0.0f, 0.0f);
// The light vector aims opposite the direction the light rays travel.
float3 lightVec = -L.Direction;
// Add ambient term.
ambient = mat.Ambient * L.Ambient;
// Add diffuse and specular term, provided the surface is in
// the line of site of the light.
float diffuseFactor = dot(lightVec, normal);
// Flatten to avoid dynamic branching.
[flatten]
if (diffuseFactor > 0.0f)
{
float3 v = reflect(-lightVec, normal);
float specFactor = pow(max(dot(v, toEye), 0.0f), mat.Specular.w);
diffuse = diffuseFactor * mat.Diffuse * L.Diffuse;
spec = specFactor * mat.Specular * L.Specular;
}
}
I'm using DirectX 11.
