#include <phong_lighting.cg>
#include <fragment_entry.cg>

DECLARE_TEXTURE(diffuseTexture)

uniform const float3 outlineColor = {0.0, 0.0, 0.0};
uniform const float  invTexWidth  = 1.0/1024.0;
uniform const float  invTexHeight = 1.0/1024.0;

// should replace the blur with a separable version or some such
SurfaceMaterial computeSurfaceMaterial(const FragmentParameters params)
{
	half4 diffuseTextureColor = tex2D(diffuseTexture, params.texcoord0.xy);
	
	half coeffs[9]= { 1.0/16.0, 2.0/16.0, 1.0/16.0,
	                  2.0/16.0, 4.0/16.0, 2.0/16.0,
	                  1.0/16.0, 2.0/16.0, 1.0/16.0 };
	                      
	float accum = 0.0;
	accum += tex2D(diffuseTexture, params.texcoord0.xy + half2(-invTexWidth, -invTexHeight)).a * coeffs[0];
	accum += tex2D(diffuseTexture, params.texcoord0.xy + half2(           0, -invTexHeight)).a * coeffs[1];
	accum += tex2D(diffuseTexture, params.texcoord0.xy + half2(invTexWidth,  -invTexHeight)).a * coeffs[2];
	accum += tex2D(diffuseTexture, params.texcoord0.xy + half2(-invTexWidth, 0 )).a * coeffs[3];
	accum += diffuseTextureColor.a * coeffs[4];
	accum += tex2D(diffuseTexture, params.texcoord0.xy + half2(invTexWidth,  0 )).a * coeffs[5];
	accum += tex2D(diffuseTexture, params.texcoord0.xy + half2(-invTexWidth, invTexHeight)).a * coeffs[6];
	accum += tex2D(diffuseTexture, params.texcoord0.xy + half2(           0, invTexHeight)).a * coeffs[7];
	accum += tex2D(diffuseTexture, params.texcoord0.xy + half2(invTexWidth,  invTexHeight)).a * coeffs[8];
	
	SurfaceMaterial mout;
	mout.diffuseColor       = lerp(outlineColor, params.color.rgb, diffuseTextureColor.a);
	mout.alpha              = diffuseTextureColor.a*params.color.a + accum;
	mout.emissiveColor      = 0;
	mout.specularColor      = half3(1,1,1); // TODO: make this a constant parameter set by the material.
	mout.specularPower      = 16;
	mout.tangentSpaceNormal = half3(0,0,1);
	return mout;
}