-> ->

struct VS_IN
{
	float4 pos      : POSITION;
	float3 normal   : NORMAL;
	float2 texCoord : TEXCOORD0;
	float3 tangent  : TANGENT;
	float3 binormal : BINORMAL;
};

struct VS_OUT
{
	float4 pos 	: POSITION;
	float2 texCoord : TEXCOORD0;
	float3 eyeVec   : TEXCOORD1;
};

VS_OUT ParallaxVS(VS_IN inVertex)
{
	VS_OUT outVertex;
	
	//basic stuff
	outVertex.pos  = mul(inVertex.pos, s_matWorldViewProj);
	outVertex.tex  = inVertex.tex;
		
	//get eye vector
	float3 worldVert = mul(inVertex.pos, s_matWorld);
	float3 eye       = s_matViewInv[3] - worldVert;
	
	//get tangent matrix
	float3x3 matTangent;
	matTangent[0] = normalize(mul(inVertex.tangent,  (float3x3)s_matWorld));
	matTangent[1] = normalize(mul(inVertex.binormal, (float3x3)s_matWorld));
	matTangent[2] = normalize(mul(inVertex.normal,   (float3x3)s_matWorld));

	//bring eye into tangent space
	outVertex.toEye = mul(matTangent, eye);
		
	return outVertex;
}

float4 ParallaxPS(VS_OUT inPixel)
{
	//get height value
	float height = tex2D(heightMapSampler, inPixel.tex).x;
	 
	//get look vector
	float2 look = normalize(inPixel.toEye).xy;  //only use the xy componentents
	
	//offset texture coord by the look vector times a scaled and biased height
	float2 newTC  = inPixel.tex + (look*(height*0.04 - 0.02f));
	
	//texture color
	float4 diffuse = tex2D(diffuseTextureSampler, newTC);  //note that we are using the offsetted texture coordinate now
	
	return diffuse;
}

	
	//create a new vert decleration
	D3DVERTEXELEMENT9 vertDecl[] = 
	{
		{ 0, 0,  D3DDECLTYPE_FLOAT3, D3DDECLMETHOD_DEFAULT, D3DDECLUSAGE_POSITION, 0 },
		{ 0, 12, D3DDECLTYPE_FLOAT3, D3DDECLMETHOD_DEFAULT, D3DDECLUSAGE_NORMAL,   0 },
		{ 0, 24, D3DDECLTYPE_FLOAT2, D3DDECLMETHOD_DEFAULT, D3DDECLUSAGE_TEXCOORD, 0 },
		{ 0, 32, D3DDECLTYPE_FLOAT3, D3DDECLMETHOD_DEFAULT, D3DDECLUSAGE_TANGENT,  0 },
		{ 0, 44, D3DDECLTYPE_FLOAT3, D3DDECLMETHOD_DEFAULT, D3DDECLUSAGE_BINORMAL, 0 },
		D3DDECL_END()
	};

	//clonedMesh is where the new mesh with the new vertexDecl will be, and new mesh will be passed into the ComputeTangent function. Compute tangent
	//might modify some vertices to get correct tangent data so it needs this mesh.
	LPD3DXMESH clonedMesh, newMesh;

	//clone your mesh with new data and store it in clonedMesh
	yourMesh->CloneMesh(D3DXMESH_VB_MANAGED, vertDecl, d3dDevice, &clonedMesh);
	
	//release old mesh
	yourMesh->Release();

	//And heres what you really need
	D3DXComputeTangentFrameEx( clonedMesh, D3DDECLUSAGE_TEXCOORD, 0, D3DDECLUSAGE_TANGENT, 0,
                               D3DX_DEFAULT, 0, D3DDECLUSAGE_NORMAL, 0,
                               D3DXTANGENT_CALCULATE_NORMALS,
			       NULL, -1, 0, -1, &newMesh, NULL );


	//don't need clonedMesh anymore
	clonedMesh->Release();
	
	//set new mesh to the one that was created
	mesh_    = newMesh;
	newMesh  = 0;
	

	//store tangent and binormal data in texture coordinates
	DWORD newFVF = D3DFVF_XYZ | D3DFVF_NORMAL | D3DFVF_TEX3 | D3DFVF_TEXCOORDSIZE2(0) | D3DFVF_TEXCOORDSIZE3(1) | D3DFVF_TEXCOORDSIZE3(2);
	
	//create the new mesh
	LPD3DXMESH fvfMesh;
	
	//you need to clone the fvf before you do anything else
	yourMesh->CloneMeshFVF(D3DXMESH_VB_MANAGED , newFVF, d3dDevice, &fvfMesh);
	
	//Now you need to use this fvfMesh to do the rest of what was done above with the vertexDecl method. 
	// D3DXComputeTangentFrameEx won't work with fvf stuff. It requires the correct vertexDecl, so you 
	//still have to do what was described above this code.  Also, note that if you do it this way
	//then in your input vertex struct for your vertex shader, you need to change the TANGENT and BINORMAL
	// symmantics to TEXCOORD1 and TEXCOORD2 or else DX will give you an error if run using the debug runtime.
	// Also some graphics cards (ATI >_<) don't like it if those are wrong.