Hey Guys,
I am doing lighting of an object in a shader (using directx) but when i rotate the object, the lit part on the object rotates along with it instead of facing the light source.
Anyone know what I'm doing wrong? Thank you (shader source below)
//////////////////////////////////////////////////////////////////////
// STRUCTURES
//////////////////////////////////////////////////////////////////////
// Vertex shader output structure
struct VS_OUTPUT
{
float4 Position : POSITION;
float2 Texture : TEXCOORD0;
float4 Color : COLOR0;
float3 Light : TEXCOORD1;
float3 Norm : TEXCOORD2;
};
//////////////////////////////////////////////////////////////////////
// GLOBALS
//////////////////////////////////////////////////////////////////////
// vertex globals
float4x4 WorldViewProj;
float4x4 InvTransposeWorld;
float4 Diffuse;
// pixel variables
sampler2D Tex0;
//////////////////////////////////////////////////////////////////////
// VERTEX
//////////////////////////////////////////////////////////////////////
VS_OUTPUT vs_main( float4 Position : POSITION, float2 Texture : TEXCOORD0, float3 Normal : NORMAL )
{
VS_OUTPUT Out; //create an output vertex
Out.Position = mul(Position,WorldViewProj); //apply vertex transformation
Out.Texture = Texture; //copy original texcoords
Out.Color = Diffuse;
Out.Light = normalize(float3(3,2,-1));
Out.Norm = normalize(mul(InvTransposeWorld,Normal));
return Out; //return output vertex
}
//////////////////////////////////////////////////////////////////////
// PIXEL
//////////////////////////////////////////////////////////////////////
float4 ps_main( float2 Texture : TEXCOORD0, float4 Color : COLOR0, float3 Light : TEXCOORD1, float3 Norm : TEXCOORD2) : COLOR
{
float4 Out;
//look up texture, multiply by color tint, then multiply by ambient light
Out = tex2D(Tex0, Texture);
Out *= Color;
Out *= float4(0.2,0.2,0.2,1.0);
//apply lighting
Out += saturate(dot(Light,Norm)) * float4(0.5,0.0,0.0,0.0);
return Out;
}
Also, i do this every frame (C++) to update the values. The object looks correct but the lighting is wrong.
oid CShader::ApplyShader()
{
//communicate with shader
D3DXMATRIXA16 matWorld, matView, matProj;
LowLevel.D3Ddevice->GetTransform(D3DTS_WORLD, &matWorld);
LowLevel.D3Ddevice->GetTransform(D3DTS_VIEW, &matView);
LowLevel.D3Ddevice->GetTransform(D3DTS_PROJECTION, &matProj);
//make the world view projection matrix and pass it to the shader (useful for projecting 3d to 2d)
D3DXMATRIXA16 matWorldViewProj = matWorld * matView * matProj;
ConstantTable->SetMatrix(LowLevel.D3Ddevice,
"WorldViewProj",
&matWorldViewProj);
//make the inverse transpose world matrix and pass it to the shader (useful for lighting)
D3DXMATRIXA16 matInverseTransposeWorld;
float Determinant;
D3DXMatrixInverse(&matInverseTransposeWorld,&Determinant,&matWorld);
D3DXMatrixTranspose(&matInverseTransposeWorld,&matInverseTransposeWorld);
ConstantTable->SetMatrix(LowLevel.D3Ddevice,
"InvTransposeWorld",
&matInverseTransposeWorld);
LowLevel.D3Ddevice->SetVertexDeclaration(VertexDecl);
LowLevel.D3Ddevice->SetVertexShader(VertexShader);
LowLevel.D3Ddevice->SetPixelShader(PixelShader);
}
