shader_type spatial;
render_mode unshaded;
uniform bool is_open = false;
uniform int mark_type = 0; //0空气墙 1黑块 2绿幕

uniform sampler2D tex : source_color;
uniform sampler2D tex_sub1 : source_color;


void fragment() {
	if (is_open){
		if (mark_type == 0){
			discard;
		}else if (mark_type == 1){
        	ALBEDO = vec3(0.0);
		}else if (mark_type == 2){
			vec3 color = vec3(0.0);
			vec4 background = textureLod(tex, SCREEN_UV, 0.0);
			vec4 background_sub1 = textureLod(tex_sub1, SCREEN_UV, 0.0);
			if (background.a > 0.0){
				color.rgb = background.rgb;
			}
			if (background_sub1.a > 0.0){
				color.rgb = background_sub1.rgb;
			}
        	ALBEDO = color;
		}
	}else{
		ALBEDO = COLOR.rgb;
	}
}