#version 120

// Varying.
varying vec3 worldNormal;
varying vec3 worldPos;

// Misc uniforms.
uniform vec3 camPos;
uniform mat4 obj2World;
uniform mat4 world2Cam;

// Surface calculations, including specular power.
varying vec2 texCoord;
vec4 viewDelta;

// Fogging.
uniform vec4 fogBaseColor;
uniform vec4 fogConsts;
uniform sampler2D fogTex;
varying vec2 fogCoords;

void main()
{
	// Bricks always in world space.
 	worldPos = (obj2World * vec4(gl_Vertex.xyz, 1.0f)).xyz;
 	worldNormal = ((obj2World * vec4(gl_Normal.xyz, 0.0f)).xyz);

 	if(length(gl_Normal.xyz) < 1.1f)
 		worldNormal.xyz = normalize(worldNormal.xyz);

	// Do some camera delta math.
	viewDelta.xyz = worldPos - camPos;
	viewDelta.w   = length(viewDelta.xyz);
	viewDelta.xyz = -normalize(viewDelta.xyz);
	worldPos.z -= pow(viewDelta.w*-0.012, 2);

	// Fog can be done per-vertex.
	fogCoords.x = clamp((fogConsts.y - viewDelta.w) * fogConsts.x, 0.0f, 1.0f);
	fogCoords.y = clamp((worldPos.z - fogConsts.z) * fogConsts.w, 0.0f, 1.0f);

 	// Project the brick pos and normal.
	gl_Position = gl_ProjectionMatrix * world2Cam * vec4(worldPos, 1.0f);

	// Pass color through.
	gl_FrontColor = gl_Color;
	
	// Pass texcoords through.
	texCoord = gl_MultiTexCoord0.st;	
}