shader_type spatial;
render_mode unshaded;

#include "res://vfx/util.gdshaderinc"

uniform sampler2D viewport_texture: source_color, hint_screen_texture;
uniform sampler2D viewport_depth_texture: source_color, hint_depth_texture;
uniform sampler2D image: source_color, hint_default_transparent;
uniform float far = 4000.0;

void vertex() {
	POSITION = vec4(VERTEX.xyz, 1.0);
}

void fragment() {
	DEPTH = texture(viewport_depth_texture, SCREEN_UV).x;
	float linear_depth = linearize_depth(
		DEPTH, SCREEN_UV, INV_PROJECTION_MATRIX
	);
	if (linear_depth > far) {
		ALBEDO = alpha_blend(
			texture(image, SCREEN_UV),
			texture(viewport_texture, SCREEN_UV)
		).rgb;
	} else {
		ALBEDO = texture(viewport_texture, SCREEN_UV).rgb;
	}
}