Shader Examples: Diffuse Shader

varying vec3 normal;
varying vec3 vertex_to_light_vector;

void main()
{
	// Defining The Material Colors
	const vec4 AmbientColor = vec4(0.1, 0.0, 0.0, 1.0);
	const vec4 DiffuseColor = vec4(1.0, 0.0, 0.0, 1.0);

	// Scaling The Input Vector To Length 1
	vec3 normalized_normal = normalize(normal);
	vec3 normalized_vertex_to_light_vector = normalize(vertex_to_light_vector);

	// Calculating The Diffuse Term And Clamping It To [0;1]
	float DiffuseTerm = clamp(dot(normal, vertex_to_light_vector), 0.0, 1.0);

	// Calculating The Final Color
	gl_FragColor = AmbientColor + DiffuseColor * DiffuseTerm;
}