uniform Lighting
{
	vec3 light_dir[3];
};
uniform mat4 model_matrix;
uniform mat4 view_matrix;
uniform mat4 proj_matrix;

#pragma MSP stage(vertex)
layout(location=0) in vec4 vertex;
void main()
{
	out vec4 world_vertex = model_matrix*vertex;
	vec3 eye_pos = inverse(view_matrix)[3].xyz;
	out vec3 world_look_dir = normalize(world_vertex.xyz-eye_pos);
	gl_Position = proj_matrix*view_matrix*world_vertex;
}

#pragma MSP stage(fragment)
layout(location=0) out vec4 frag_color;
float calculate_lighting(vec3 look_dir)
{
	float intensity = 0.0;
	for(int i=0; i<3; ++i)
		intensity += max(dot(look_dir, light_dir[i]), 0.0);
	return intensity;
}
void main()
{
	float light_intensity = calculate_lighting(world_look_dir);
	frag_color = vec4(vec3(light_intensity), 1.0);
}

/* Expected output: vertex
layout(location=0) uniform mat4 model_matrix;
layout(location=4) uniform mat4 view_matrix;
layout(location=8) uniform mat4 proj_matrix;
layout(location=0) in vec4 vertex;
layout(location=0) out vec4 world_vertex;
layout(location=1) out vec3 world_look_dir;
void main()
{
	world_vertex = model_matrix*vertex;
	world_look_dir = normalize(world_vertex.xyz-inverse(view_matrix)[3].xyz);
	gl_Position = proj_matrix*view_matrix*world_vertex;
}
*/

/* Expected output: fragment
layout(binding=5) uniform Lighting
{
	vec3 light_dir[3];
};
layout(location=0) out vec4 frag_color;
float calculate_lighting(vec3 look_dir)
{
	float intensity = 0.0;
	for(int i = 0; i<3; ++i)
		intensity += max(dot(look_dir, light_dir[i]), 0.0);
	return intensity;
}
layout(location=1) in vec3 world_look_dir;
void main()
{
	frag_color = vec4(vec3(calculate_lighting(world_look_dir)), 1.0);
}
*/