uniform mat4 mvpMatrix;
uniform mat4 rotationMatrix;

attribute vec3 position;
attribute vec3 normal;
attribute vec4 color;

varying vec4 colorVarying;
varying float lightIntensity;

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

    vec4 rotatedNormal = rotationMatrix * vec4(normal, 1.0);
    lightIntensity = dot(rotatedNormal.xyz, normalize(vec3(0.2, 0.9, -1.0)));

    colorVarying = color;
}