DiffuseVertex.glsl

layout(location = 0) in vec3 inVert;
layout(location = 1) in vec3 inNormal;
layout(location = 2) in vec3 inUV;

// Model View Projection matrix
uniform mat4 MVP;
// Model View matrix
uniform mat4 MV;
// Normal matrix
uniform mat3 NormalMatrix;

struct Lights
{
	// Position in eye coordinates
	vec4 position;

	// Diffuse reflectivity
	vec4 Kd;

	// Light source intensity
	vec4 Ld;
};

// Light data passed in from the client
uniform Lights light;

// Output to the fragment shader (interpolated)
out vec3 LightIntensity;

void main()
{
	// Convert normal to eye space
	vec3 nrmN = normalize(NormalMatrix * inNormal);

	// Convert vertex to eye space (we convert it to vec4 so the multiply by matrix works)
	vec4 eye = MV * vec4(inVert, 1);

	// Get direction to the light
	vec3 lightNrm = normalize( eye - light.position );

	// Calculate diffuse (lambert reflectance)
	vec3 lambert = dot(nrmN, lightNrm);

	// Intensity is the diffuse value multiplied by the light colour and intensity
	LightIntensity = light.Ld * light.Kd * max(lambert, 0.0);

	// Position is the input vertex transformed by the model view projection matrix
	gl_Position = MVP * vec4(inVert,1);
}