cube2.vert

#version 330


uniform mat4 viewProj;


uniform vec3 rotationQuat;
uniform vec3 cubePos;
uniform vec3 color;
in vec3 position;
out vec3 colorFrag;


void main(void)
{
	// our quaternions are normalized and have w > 0.0
	float qw = sqrt(1.0 - dot(rotationQuat, rotationQuat));
	// rotate
	// this is quaternion multiplication from glm
	vec3 v = position;
	vec3 uv = cross(rotationQuat, v);
	vec3 uuv = cross(rotationQuat, uv);
	uv *= (2.0 * qw);
	uuv *= 2.0;
	vec3 rotatedPos = v + uv + uuv;

	gl_Position = viewProj * vec4(rotatedPos + cubePos, 1.0);
	colorFrag = color;
}