uniform vec4 uDiffuseColor;
uniform vec4 uAmbientColor;
uniform vec3 uSpecularColor;
uniform float uShininess;
uniform float uShadowStrength;
uniform vec3 uShadowColor;

// these are our new uniforms
uniform sampler2D s_scaleRef;
uniform sampler2D s_rot;
uniform vec2 u_inst_grid;
uniform float u_disp_scale;
uniform float u_rot_max;

// a new rotate funciton
vec2 rotate2D(float angle, vec2 prevXY){
	mat2 transMat 	= mat2(	cos(angle), -sin(angle),
							sin(angle), cos(angle));
	vec2 new_rot 	= transMat * prevXY;
	return new_rot;
}

out Vertex
{
	vec4 color;
	vec3 worldSpacePos;
	vec3 worldSpaceNorm;
	vec3 texCoord0;
	flat int cameraIndex;
} oVert;

void main()
{
	// here we use the grid size to crate a UV lookup for our texture
	vec2 samplerLookup	 	= TDInstanceTranslate().xy / (u_inst_grid/2);
	samplerLookup 			= (samplerLookup / 2) + 0.5;

	// here we grab the alpha value from our texture to determine scale
	float scale 			= texture(s_scaleRef, samplerLookup).a * u_disp_scale;

	// let's also grab our texture for rotation
	float rotAngle 			= texture(s_rot, samplerLookup).r * u_rot_max;

	// rotate the instance
	vec2 instRot  			= rotate2D(rotAngle, TDInstanceTranslate().xy);

	vec3 new_p 				= P;

	new_p.xy 				+= instRot;

	// scale the instance
	new_p 					*= scale;

	// First deform the vertex and normal
	// TDDeform always returns values in world space
	vec4 worldSpacePos =TDDeform(new_p);
	gl_Position = TDWorldToProj(worldSpacePos);

	// This is here to ensure we only execute lighting etc. code
	// when we need it. If picking is active we don't need this, so
	// this entire block of code will be ommited from the compile.
	// The TD_PICKING_ACTIVE define will be set automatically when
	// picking is active.
#ifndef TD_PICKING_ACTIVE

	{ // Avoid duplicate variable defs
		vec3 texcoord = TDInstanceTexCoord(uv[0]);
		oVert.texCoord0.stp = texcoord.stp;
	}
	int cameraIndex = TDCameraIndex();
	oVert.cameraIndex = cameraIndex;
	oVert.worldSpacePos.xyz = worldSpacePos.xyz;
	oVert.color = TDInstanceColor(Cd);
	vec3 worldSpaceNorm = normalize(TDDeformNorm(N));
	oVert.worldSpaceNorm.xyz = worldSpaceNorm;

#else // TD_PICKING_ACTIVE

	// This will automatically write out the nessessary values
	// for this shader to work with picking.
	// See the documentation if you want to write custom values for picking.
	TDWritePickingValues();

#endif // TD_PICKING_ACTIVE
}