polyvox/media/materials/programs/ColourMap3DVertexProgram.cg
2007-10-08 21:26:13 +00:00

95 lines
3.1 KiB
Plaintext

//NOTE - The code in this file might seem slightly strange. Intuitivy it would
//seem better to get Ogre to pass in an array of lights, rather than passing
//them individually and then building arrays. However, I have had problms with
//this approach (possibly a bug?)
//See http://www.ogre3d.org/phpBB2/viewtopic.php?t=32391
struct a2v
{
float4 Position : POSITION; //in object space
float3 Normal : NORMAL;
};
struct v2f
{
float4 Position : POSITION; //in projection space
float4 Color : COLOR;
float4 TexCoords : TEXCOORD0;
};
struct light
{
float4 position;
float4 diffuseColour;
float4 attenuation;
};
v2f doWork(a2v IN, float4x4 world, float4x4 viewProj, float textureScale, uniform float4 ambient, int iNoOfLights, light lights[4])
{
v2f OUT;
OUT.Position = mul(world, IN.Position);
OUT.TexCoords.xyz = OUT.Position.xyz /textureScale;
OUT.TexCoords.w = 1;
OUT.Color.rgba = float4(0.0,0.0,0.0,1.0);
for(int lightCt = 0; lightCt < iNoOfLights; lightCt++)
{
float3 L = normalize(lights[lightCt].position.xyz - OUT.Position.xyz);
//Calculate attenuation factor.
float d = distance(lights[lightCt].position.xyz, OUT.Position.xyz);
float attenuationFactor = 1.0 / (lights[lightCt].attenuation.y + lights[lightCt].attenuation.z * d + lights[lightCt].attenuation.w * d * d);
// Calculate diffuse component
float LdotN = max(dot(L, IN.Normal) , 0);
OUT.Color.rgb += lights[lightCt].diffuseColour.rgb * LdotN * attenuationFactor;
}
OUT.Color.rgb += ambient.rgb;
OUT.Position = mul(viewProj, OUT.Position);
return OUT;
}
v2f OneLight(a2v IN,uniform float4x4 world, uniform float4x4 viewProj, uniform float textureScale, uniform float4 ambient, uniform light light0)
{
light lights[4];
lights[0] = light0;
return doWork(IN, world, viewProj, textureScale, ambient, 1, lights);
}
v2f TwoLights(a2v IN,uniform float4x4 world, uniform float4x4 viewProj, uniform float textureScale, uniform float4 ambient, uniform light light0, uniform light light1)
{
light lights[4];
lights[0] = light0;
lights[1] = light1;
return doWork(IN, world, viewProj, textureScale, ambient, 2, lights);
}
v2f ThreeLights(a2v IN,uniform float4x4 world, uniform float4x4 viewProj, uniform float textureScale, uniform float4 ambient, uniform light light0, uniform light light1, uniform light light2)
{
light lights[4];
lights[0] = light0;
lights[1] = light1;
lights[2] = light2;
return doWork(IN, world, viewProj, textureScale, ambient, 3, lights);
}
v2f FourLights(a2v IN,uniform float4x4 world, uniform float4x4 viewProj, uniform float textureScale, uniform float4 ambient, uniform light light0, uniform light light1, uniform light light2, uniform light light3)
{
light lights[4];
lights[0] = light0;
lights[1] = light1;
lights[2] = light2;
lights[3] = light3;
return doWork(IN, world, viewProj, textureScale, ambient, 4, lights);
}