#version 330

in vec3 vertexPosition;
in vec2 vertexTexCoord;
in vec3 vertexNormal;
in vec4 vertexColor;

uniform mat4 mvp;
uniform mat4 matNormal;

out vec2 frag_texcoord;
out vec4 frag_colour;
out vec3 frag_world_normal;

void
main() {
	frag_texcoord = vertexTexCoord;
	frag_colour = vertexColor;

	/*
	 * Do not necessarily normalize here. Interpolation changes the
	 * length, so the fragment shader must normalize it regardless.
	 */
	frag_world_normal =
		(matNormal * vec4(vertexNormal, 0.0)).xyz;

	gl_Position = mvp * vec4(vertexPosition, 1.0);
}