const int max_samples = 32;

uniform mat4 projection_matrix;

uniform sampler2D depth;
uniform sampler2D occlusion;
uniform sampler2D rotate;
uniform AmbientOcclusionParams
{
	mat4 inverse_projection;
	float darkness;
	vec3 sample_points[max_samples];
	int n_samples;
	float occlusion_radius;
	float edge_depth_threshold;
};

#pragma MSP stage(fragment)
vec3 project(vec3 position)
{
	if(position.z>=0.0)
		return vec3(0.0, 0.0, -1.0);
	vec4 pp = projection_matrix*vec4(position, 1.0);
	return pp.xyz/pp.w;
}

vec3 unproject(vec3 position)
{
	vec4 upp = inverse_projection*vec4(position, 1.0);
	return upp.xyz/upp.w;
}