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LWJGL Shader Tutorials / src / main / java / com / ra4king / opengl / arcsynthesis / gl33 / chapter10 / example2 / example10.2.VertexLighting_PN.vert

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#version 330

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