/*******************************************************************************
 *
 * Simple HLSL FX file
 *
 *******************************************************************************/

// un-tweakables



// structures and shaders /////////////////////


float4x4 wvIT : WorldViewInverseTranspose;
float4x4 wvp : WorldViewProjection;

void mainVS( float4 vertex : POSITION0,
             float3 normal : NORMAL0,
             float4 tex : TEXCOORD0,
             out float4 Position  : POSITION0,
             out float3 eyeNormal : TEXCOORD0,
             out float4 texCoord  : TEXCOORD1
            )
{ 


	//	
	//
	Position = mul( vertex, wvp);

	//	Transform to shading space (we are going to shade in eyespace)
	//
	//
	eyeNormal = mul( normal, float3x3(wvIT));
	
	texCoord = tex;
}

// hatching parameters
sampler2D hatch0;
sampler2D hatch1;
sampler2D weight0;
sampler2D weight1;

float3 strokeColor = float3( 0.15, 0.05, 0.05);
float3 surfaceColor = float3( 0.9, 0.9, 0.9);

float3 lightDir = float3( 0.57735, 0.57735, 0.57735);

float4 mainPS(  float3 eyeNormal : TEXCOORD0, float4 texCoord : TEXCOORD1 ) : COLOR0 {
  float3 norm;
  float3 color;
  float illum;
  
  float3 lightDirection = normalize(lightDir);
  
  float4 Intensity;
  
  //
  //	Since the EyeNormal is getting interpolated, we
  //	have to first restore it by normalizing it.
  //
  norm = normalize( eyeNormal);

  //compute diffuse illumination
  illum = saturate( dot(norm, lightDirection));
  
  float3 h0 = float3( tex2D( hatch0, texCoord));
  float3 h1 = float3( tex2D( hatch1, texCoord));
  float3 w0 = float3( tex2D( weight0, float2(illum)));
  float3 w1 = float3( tex2D( weight1, float2(illum)));

  // compute the weighting for the different hatching directions
  float weight = saturate( saturate(dot(1.0-h0,w0)) + saturate(dot(1.0-h1,w1)) );

  // blend between dark and light colors
  color = lerp(surfaceColor, strokeColor, weight);

  float4 result = float4(color, 1.0);

  return result;

}


//////// techniques ////////////////////////////

technique BumpReflect0
{
	pass p0
	{
		VertexShader = compile vs_2_0 mainVS();
		
		ZEnable = true;
		ZWriteEnable = true;
        ZFunc = LEqual;
		CullMode = None;

		PixelShader = compile ps_2_0 mainPS();
	}
}