50 lines
1.3 KiB
HLSL
50 lines
1.3 KiB
HLSL
#include "Header.hlsli"
|
|
|
|
|
|
|
|
float3x3 cotangent_frame( float3 N, float3 p, float2 uv )
|
|
{
|
|
// get edge vectors of the pixel triangle
|
|
float3 dp1 = ddx( p );
|
|
float3 dp2 = ddy( p );
|
|
float2 duv1 = ddx( uv );
|
|
float2 duv2 = ddy( uv );
|
|
|
|
// solve the linear system
|
|
float3 dp2perp = cross( dp2, N );
|
|
float3 dp1perp = cross( N, dp1 );
|
|
float3 T = dp2perp * duv1.x + dp1perp * duv2.x;
|
|
float3 B = dp2perp * duv1.y + dp1perp * duv2.y;
|
|
|
|
// construct a scale-invariant frame
|
|
float invmax = 1/sqrt( max( dot(T,T), dot(B,B) ) );
|
|
return float3x3( T * invmax, B * invmax, N );
|
|
}
|
|
|
|
float3 perturb_normal( float3 N, float3 V, float2 texcoord )
|
|
{
|
|
// assume N, the interpolated vertex normal and
|
|
// V, the view vector (vertex to eye)
|
|
float3 map = Normal.Sample(S1,texcoord).xyz;
|
|
map = map * 255./127. - 128./127.;
|
|
#ifdef WITH_NORMALMAP_2CHANNEL
|
|
map.z = sqrt( 1. - dot( map.xy, map.xy ) );
|
|
#endif
|
|
#ifdef WITH_NORMALMAP_GREEN_UP
|
|
map.y = -map.y;
|
|
#endif
|
|
float3x3 TBN = cotangent_frame( N, -V, texcoord );
|
|
return normalize( mul(transpose(TBN), map) );
|
|
}
|
|
|
|
PixelOut main(VertexOut input)
|
|
{
|
|
PixelOut output;
|
|
output.DiffuseGlow = Diffuse.Sample(S1, input.UV);
|
|
float3 normal = normalize(input.normal);
|
|
|
|
normal = perturb_normal( normal, normalize(-input.ViewPos), input.UV );
|
|
|
|
output.NormalSpec = float4(normal, Normal.Sample(S1,input.UV).w);
|
|
return output;
|
|
} |