/*
  Basic ambient lighting vertex program
*/
void ambientOneTexture_vp(float4 position : POSITION,
						  float2 uv		  : TEXCOORD0,
						  
						  out float4 oPosition : POSITION,
						  out float2 oUv	   : TEXCOORD0,
						  out float4 colour    : COLOR,

						  uniform float4x4 worldViewProj,
						  uniform float4 ambient)
{
	oPosition = mul(worldViewProj, position);
	oUv = uv;
	colour = ambient;
}

/*
  Basic fragment program using texture and diffuse colour.
*/
void diffuseOneTexture_fp(float4 position          : POSITION, 
						  float2 uv                : TEXCOORD0,
						  float4 diffuse           : COLOR,
						  out float4 colour        : COLOR,
						  uniform sampler2D texMap : register(s0))
{
	colour = tex2D(texMap,uv) * diffuse;
}
			  
/*
  Single-weight-per-vertex hardware skinning, 2 lights
  The trouble with vertex programs is they're not general purpose, but
  fixed function hardware skinning is very poorly supported
*/
void hardwareSkinningOneWeight_vp(
	float4 position : POSITION,
	float3 normal   : NORMAL,
	float2 uv       : TEXCOORD0,
	float  blendIdx : BLENDINDICES,
	

	out float4 oPosition : POSITION,
	out float2 oUv       : TEXCOORD0,
	out float4 colour           : COLOR,
	// Support up to 24 bones of float3x4
	// vs_1_1 only supports 96 params so more than this is not feasible
	uniform float3x4   worldMatrix3x4Array[24],
	uniform float4x4 viewProjectionMatrix,
	uniform float4   lightPos[2],
	uniform float4   lightDiffuseColour[2],
	uniform float4   ambient)
{
	// transform by indexed matrix
	float4 blendPos = float4(mul(worldMatrix3x4Array[blendIdx], position).xyz, 1.0);
	// view / projection
	oPosition = mul(viewProjectionMatrix, blendPos);
	// transform normal
	float3 norm = mul((float3x3)worldMatrix3x4Array[blendIdx], normal);
	// Lighting - support point and directional
	float3 lightDir0 = 	normalize(
		lightPos[0].xyz -  (blendPos.xyz * lightPos[0].w));
	float3 lightDir1 = 	normalize(
		lightPos[1].xyz -  (blendPos.xyz * lightPos[1].w));

	oUv = uv;
	colour = ambient + 
		(saturate(dot(lightDir0, norm)) * lightDiffuseColour[0]) + 
		(saturate(dot(lightDir1, norm)) * lightDiffuseColour[1]);
	
}	

/*
  Single-weight-per-vertex hardware skinning, shadow-caster pass
*/
void hardwareSkinningOneWeightCaster_vp(
	float4 position : POSITION,
	float3 normal   : NORMAL,
	float  blendIdx : BLENDINDICES,
	

	out float4 oPosition : POSITION,
	out float4 colour    : COLOR,
	// Support up to 24 bones of float3x4
	// vs_1_1 only supports 96 params so more than this is not feasible
	uniform float3x4   worldMatrix3x4Array[24],
	uniform float4x4 viewProjectionMatrix,
	uniform float4   ambient)
{
	// transform by indexed matrix
	float4 blendPos = float4(mul(worldMatrix3x4Array[blendIdx], position).xyz, 1.0);
	// view / projection
	oPosition = mul(viewProjectionMatrix, blendPos);
	
	colour = ambient;
	
}	

/*
  Two-weight-per-vertex hardware skinning, 2 lights
  The trouble with vertex programs is they're not general purpose, but
  fixed function hardware skinning is very poorly supported
*/
void hardwareSkinningTwoWeights_vp(
	float4 position : POSITION,
	float3 normal   : NORMAL,
	float2 uv       : TEXCOORD0,
	float4 blendIdx : BLENDINDICES,
	float4 blendWgt : BLENDWEIGHT,
	

	out float4 oPosition : POSITION,
	out float2 oUv       : TEXCOORD0,
	out float4 colour           : COLOR,
	// Support up to 24 bones of float3x4
	// vs_1_1 only supports 96 params so more than this is not feasible
	uniform float3x4   worldMatrix3x4Array[24],
	uniform float4x4 viewProjectionMatrix,
	uniform float4   lightPos[2],
	uniform float4   lightDiffuseColour[2],
	uniform float4   ambient,
	uniform float4   diffuse)
{
	// transform by indexed matrix
	float4 blendPos = float4(0,0,0,0);
	int i;
	for (i = 0; i < 2; ++i)
	{
		blendPos += float4(mul(worldMatrix3x4Array[blendIdx[i]], position).xyz, 1.0) * blendWgt[i];
	}
	// view / projection
	oPosition = mul(viewProjectionMatrix, blendPos);
	// transform normal
	float3 norm = float3(0,0,0);
	for (i = 0; i < 2; ++i)
	{
		norm += mul((float3x3)worldMatrix3x4Array[blendIdx[i]], normal) * 
		blendWgt[i];
	}
	norm = normalize(norm);
	// Lighting - support point and directional
	float3 lightDir0 = 	normalize(
		lightPos[0].xyz -  (blendPos.xyz * lightPos[0].w));
	float3 lightDir1 = 	normalize(
		lightPos[1].xyz -  (blendPos.xyz * lightPos[1].w));

	
	oUv = uv;
	colour = diffuse * (ambient + 
		(saturate(dot(lightDir0, norm)) * lightDiffuseColour[0]) + 
		(saturate(dot(lightDir1, norm)) * lightDiffuseColour[1]));
	
}

/*
  Two-weight-per-vertex hardware skinning, shadow caster pass
*/
void hardwareSkinningTwoWeightsCaster_vp(
	float4 position : POSITION,
	float3 normal   : NORMAL,
	float2 uv       : TEXCOORD0,
	float4 blendIdx : BLENDINDICES,
	float4 blendWgt : BLENDWEIGHT,
	

	out float4 oPosition : POSITION,
	out float4 colour           : COLOR,
	// Support up to 24 bones of float3x4
	// vs_1_1 only supports 96 params so more than this is not feasible
	uniform float3x4   worldMatrix3x4Array[24],
	uniform float4x4 viewProjectionMatrix,
	uniform float4   ambient)
{
	// transform by indexed matrix
	float4 blendPos = float4(0,0,0,0);
	int i;
	for (i = 0; i < 2; ++i)
	{
		blendPos += float4(mul(worldMatrix3x4Array[blendIdx[i]], position).xyz, 1.0) * blendWgt[i];
	}
	// view / projection
	oPosition = mul(viewProjectionMatrix, blendPos);
	

	colour = ambient;
}


/*
  Four-weight-per-vertex hardware skinning, 2 lights
  The trouble with vertex programs is they're not general purpose, but
  fixed function hardware skinning is very poorly supported
*/
void hardwareSkinningFourWeights_vp(
	float4 position : POSITION,
	float3 normal   : NORMAL,
	float2 uv       : TEXCOORD0,
	float4 blendIdx : BLENDINDICES,
	float4 blendWgt : BLENDWEIGHT,
	

	out float4 oPosition : POSITION,
	out float2 oUv       : TEXCOORD0,
	out float4 colour           : COLOR,
	// Support up to 24 bones of float3x4
	// vs_1_1 only supports 96 params so more than this is not feasible
	uniform float3x4   worldMatrix3x4Array[24],
	uniform float4x4 viewProjectionMatrix,
	uniform float4   lightPos[2],
	uniform float4   lightDiffuseColour[2],
	uniform float4   ambient)
{
	// transform by indexed matrix
	float4 blendPos = float4(0,0,0,0);
	int i;
	for (i = 0; i < 4; ++i)
	{
		blendPos += float4(mul(worldMatrix3x4Array[blendIdx[i]], position).xyz, 1.0) * blendWgt[i];
	}
	// view / projection
	oPosition = mul(viewProjectionMatrix, blendPos);
	// transform normal
	float3 norm = float3(0,0,0);
	for (i = 0; i < 4; ++i)
	{
		float3x3 d = (float3x3)worldMatrix3x4Array[blendIdx[i]];
		norm += mul(d, normal) * 
		blendWgt[i];
	}
	norm = normalize(norm);
	// Lighting - support point and directional
	float3 lightDir0 = 	normalize(
		lightPos[0].xyz -  (blendPos.xyz * lightPos[0].w));
	float3 lightDir1 = 	normalize(
		lightPos[1].xyz -  (blendPos.xyz * lightPos[1].w));

	
	oUv = uv;
	colour = ambient + 
		(saturate(dot(lightDir0, norm)) * lightDiffuseColour[0]) + 
		(saturate(dot(lightDir1, norm)) * lightDiffuseColour[1]);
	
}

// hardware morph animation (no normals)
void hardwareMorphAnimation(float3 pos1 : POSITION,
			  float4 normal		: NORMAL,
			  float2 uv		  : TEXCOORD0,
			  float3 pos2	  : TEXCOORD1,
						  
			  out float4 oPosition : POSITION,
			  out float2 oUv	   : TEXCOORD0,
			  out float4 colour    : COLOR,

			  uniform float4x4 worldViewProj, 
			  uniform float4 anim_t)
{
	// interpolate
	float4 interp = float4(pos1 + anim_t.x*(pos2 - pos1), 1.0f);
	
	oPosition = mul(worldViewProj, interp);
	oUv = uv;
	colour = float4(1,0,0,1);
}

// hardware pose animation (no normals)
void hardwarePoseAnimation(float3 pos : POSITION,
			  float4 normal		: NORMAL,
			  float2 uv		  : TEXCOORD0,
			  float3 pose1	  : TEXCOORD1,
			  float3 pose2	  : TEXCOORD2,
						  
			  out float4 oPosition : POSITION,
			  out float2 oUv	   : TEXCOORD0,
			  out float4 colour    : COLOR,

			  uniform float4x4 worldViewProj, 
			  uniform float4 anim_t)
{
	// interpolate
	float4 interp = float4(pos + anim_t.x*pose1 + anim_t.y*pose2, 1.0f);
	
	oPosition = mul(worldViewProj, interp);
	oUv = uv;
	colour = float4(1,0,0,1);
}

// hardware morph animation (with normals)
void hardwareMorphAnimationWithNormals(float3 pos1 : POSITION,
			  float3 normal1  : NORMAL,
			  float2 uv		  : TEXCOORD0,
			  float3 pos2	  : TEXCOORD1,
			  float3 normal2  : TEXCOORD2,
						  
			  out float4 oPosition : POSITION,
			  out float2 oUv	   : TEXCOORD0,
			  out float4 colour    : COLOR,

			  uniform float4x4 worldViewProj, 
			  uniform float4 objSpaceLightPos,
			  uniform float4 ambient,
			  uniform float4 anim_t)
{
	// interpolate position
	float4 posinterp = float4(pos1 + anim_t.x*(pos2 - pos1), 1.0f);

	// nlerp normal
	float3 ninterp = normal1 + anim_t.x*(normal2 - normal1);
	ninterp = normalize(ninterp);
	
	oPosition = mul(worldViewProj, posinterp);
	oUv = uv;
	
	float3 lightDir = normalize(
		objSpaceLightPos.xyz -  (posinterp.xyz * objSpaceLightPos.w));

	// Colour it red to make it easy to identify
	float lit = saturate(dot(lightDir, ninterp));
	colour = float4((ambient.rgb + float3(lit,lit,lit)) * float3(1,0,0), 1);
}

// hardware pose animation (with normals)
void hardwarePoseAnimationWithNormals(float3 pos : POSITION,
			  float3 normal	   : NORMAL,
			  float2 uv		   : TEXCOORD0,
			  float3 pose1pos  : TEXCOORD1,
			  float3 pose1norm : TEXCOORD2,
			  float3 pose2pos  : TEXCOORD3,
			  float3 pose2norm : TEXCOORD4,
						  
			  out float4 oPosition : POSITION,
			  out float2 oUv	   : TEXCOORD0,
			  out float4 colour    : COLOR,

			  uniform float4x4 worldViewProj, 
			  uniform float4 objSpaceLightPos,
			  uniform float4 ambient,
			  uniform float4 anim_t)
{
	// interpolate
	float4 posinterp = float4(pos + anim_t.x*pose1pos + anim_t.y*pose2pos, 1.0f);
	
	// nlerp normal
	// First apply the pose normals (these are actual normals, not offsets)
	float3 ninterp = anim_t.x*pose1norm + anim_t.y*pose2norm;

	// Now add back any influence of the original normal
	// This depends on what the cumulative weighting left the normal at, if it's lacking or cancelled out
	//float remainder = 1.0 - min(anim_t.x + anim_t.y, 1.0);
	float remainder = 1.0 - min(length(ninterp), 1.0);
	ninterp = ninterp + (normal * remainder);
	ninterp = normalize(ninterp);

	oPosition = mul(worldViewProj, posinterp);
	oUv = uv;
	
	float3 lightDir = normalize(
		objSpaceLightPos.xyz -  (posinterp.xyz * objSpaceLightPos.w));

	// Colour it red to make it easy to identify
	float lit = saturate(dot(lightDir, ninterp));
	colour = float4((ambient.rgb + float3(lit,lit,lit)) * float3(1,0,0), 1);
}

void basicPassthroughTangent_v(float4 position : POSITION,
						float3 tangent       : TANGENT,
						  
						  out float4 oPosition : POSITION,
						  out float3 oTangent  : TEXCOORD0,

						  uniform float4x4 worldViewProj)
{
	oPosition = mul(worldViewProj, position);
	oTangent = tangent;
}
void basicPassthroughNormal_v(float4 position : POSITION,
						float3 normal       : NORMAL,
						  
						  out float4 oPosition : POSITION,
						  out float3 oNormal  : TEXCOORD0,

						  uniform float4x4 worldViewProj)
{
	oPosition = mul(worldViewProj, position);
	oNormal = normal;
}
// Basic fragment program to display UV
float4 showuv_p (float4 position : POSITION, float2 uv : TEXCOORD0) : COLOR
{
	// wrap values using frac
	return float4(frac(uv.x), frac(uv.y), 0, 1);
}
// Basic fragment program to display 3d uv
float4 showuvdir3d_p (float4 position : POSITION, float3 uv : TEXCOORD0) : COLOR
{
	float3 n = normalize(uv);
	return float4(n.x, n.y, n.z, 1);
}