# Efficiently draw actors from the light view
class ShadowDepthProgram
	super GamnitProgramFromSource

	redef var vertex_shader_source = """
		// Vertex coordinates
		attribute vec4 coord;

		// Vertex translation
		uniform vec4 translation;

		// Vertex scaling
		uniform float scale;

		// Vertex coordinates on textures
		attribute vec2 tex_coord;

		// Vertex normal
		attribute vec3 normal;

		// Model view projection matrix
		uniform mat4 mvp;

		// Rotation matrix
		uniform mat4 rotation;

		// Output for the fragment shader
		varying vec2 v_tex_coord;

		void main()
		{
			vec4 pos = (vec4(coord.xyz * scale, 1.0) * rotation + translation);
			gl_Position = pos * mvp;

			// Pass varyings to the fragment shader
			v_tex_coord = vec2(tex_coord.x, 1.0 - tex_coord.y);
		}
		""" @ glsl_vertex_shader

	redef var fragment_shader_source = """
		precision mediump float;

		// Diffuse map
		uniform bool use_map_diffuse;
		uniform sampler2D map_diffuse;

		varying vec2 v_tex_coord;

		void main()
		{
			if (use_map_diffuse && texture2D(map_diffuse, v_tex_coord).a <= 0.01) {
				discard;
			}
		}
		""" @ glsl_fragment_shader

	# Vertices coordinates
	var coord = attributes["coord"].as(AttributeVec4) is lazy

	# Should this program use the texture `map_diffuse`?
	var use_map_diffuse = uniforms["use_map_diffuse"].as(UniformBool) is lazy

	# Diffuse texture unit
	var map_diffuse = uniforms["map_diffuse"].as(UniformSampler2D) is lazy

	# Coordinates on the textures, per vertex
	var tex_coord = attributes["tex_coord"].as(AttributeVec2) is lazy

	# Diffuse color
	var diffuse_color = uniforms["diffuse_color"].as(UniformVec4) is lazy

	# Translation applied to each vertex
	var translation = uniforms["translation"].as(UniformVec4) is lazy

	# Rotation matrix
	var rotation = uniforms["rotation"].as(UniformMat4) is lazy

	# Scaling per vertex
	var scale = uniforms["scale"].as(UniformFloat) is lazy

	# Model view projection matrix
	var mvp = uniforms["mvp"].as(UniformMat4) is lazy
end