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gltut / Tut 10 Plane Lights / data / ModelPosVertexLighting_PCN.vert

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#version 330

layout(location = 0) in vec3 position;
layout(location = 1) in vec4 inDiffuseColor;
layout(location = 2) in vec3 normal;

smooth out vec4 interpColor;

uniform vec3 modelSpaceLightPos;
uniform vec4 lightIntensity;
uniform vec4 ambientIntensity;

uniform mat4 modelToCameraMatrix;

uniform Projection
{
	mat4 cameraToClipMatrix;
};

void main()
{
	gl_Position = cameraToClipMatrix * (modelToCameraMatrix * vec4(position, 1.0));

	vec3 dirToLight = normalize(modelSpaceLightPos - position);
	
	float cosAngIncidence = dot( normal, dirToLight);
	cosAngIncidence = clamp(cosAngIncidence, 0, 1);
	
	interpColor = (lightIntensity * cosAngIncidence * inDiffuseColor) +
		(ambientIntensity * inDiffuseColor);
}