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coldy_slo

Parallax mapping shader

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Hi! I have parallax shader which is working perfectly with static geometry. Hovever, when I premultiply world and mvp matrix with rotation matrix, lighting goes really weird.
float4x4 mvp;
float4x4 world;
float3 lightPos;
float3 camPos;
float invRad;

struct VS_OUTPUT {
	float4 Pos:      POSITION;
	float2 texCoord: TEXCOORD0;
	float3 lightVec: TEXCOORD1;
	float3 viewVec:  TEXCOORD2;
};

VS_OUTPUT main(float4 pos: POSITION, float2 texCoord: TEXCOORD0, 
               float3 tangent: TEXCOORD1, float3 binormal: TEXCOORD2,
               float3 normal: TEXCOORD3)
{
	VS_OUTPUT Out;

	Out.Pos = mul(mvp, pos);
	Out.texCoord = texCoord;

	float4x4 world_pos = mul(pos, world);
	float3 lightVec = invRad * (lightPos - world_pos);
	float3 viewVec = camPos - world_pos;

	Out.lightVec.x = dot(lightVec, tangent);
	Out.lightVec.y = dot(lightVec, binormal);
	Out.lightVec.z = dot(lightVec, normal);

	Out.viewVec.x = dot(viewVec, tangent);
	Out.viewVec.y = dot(viewVec, binormal);
	Out.viewVec.z = dot(viewVec, normal);
	return Out;
}



sampler Bump;
sampler Base;

float4 lightColor;
float2 pSize;

float4 main(float2 texCoord: TEXCOORD0, float3 lightVec: TEXCOORD1, 
           float3 viewVec: TEXCOORD2) : COLOR 
{
	float atten = saturate(1 - dot(lightVec, lightVec));
	lightVec = normalize(lightVec);
	viewVec = normalize(viewVec);
	
	float height = tex2D(Bump, texCoord).a;
	float2 newTexCoord = texCoord + viewVec.xy * 
                             (height * pSize.x + pSize.y);

	float4 base = tex2D(Base, newTexCoord);
	float3 bump = tex2D(Bump, newTexCoord) * 2 - 1;

	bump = normalize(bump);

	float diffuse = saturate(dot(lightVec, bump));
	float spec = pow(saturate(dot(reflect(-viewVec, bump), lightVec)), 16);

	return lightColor * (diffuse * base + 0.7 * spec) * atten;
}
EDIT: Please remember to use 'source' tags around blocks of source code. [Edited by - jollyjeffers on October 2, 2006 9:56:13 AM]

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You have to transform the normals, binormals and tangents into world space as well. If you don't do this, your object will rotate and the lighting will rotate with it.

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