#version 410 core

// Pseudocode for incorporating texture mapping into
// a Phong lighting model

// Per-vertex attributes from vertex shader
in PVA
{
	vec3 ecPosition; // position in eye coordinates
	vec3 ecNormal; // normal vector in eye coordinates
	vec2 texCoords;
} pvaIn;

uniform sampler2D textureMap;
// You will also likely need a couple other uniforms as
// discussed in class...

// Output:
out vec4 fragColor;

// ...

vec4 composeColor(vec4 lmColor, vec4 tColor)
{
	// What color arithmetic do we want to perform?
	// Most common is to multiply the two together since this
	// simulates the lighting model acting on the texture color.
	// But you can always explore other options...
	vec4 combinedColor = the result of that color arithmetic
	return combinedColor;
}

void main (void)
{
	vec4 lightModelColor = computePhongModel();
	if using a texture map
		vec4 textureColor = texture(textureMap, pvaIn.texCoords);
		fragColor = composeColor(lightModelColor, textureColor);
	else
		fragColor = lightModelColor;
}