/*
loads decal
*/
if !variable_local_exists("var_cave_opening_loaded")
	{
	spr_decal_sprite[argument0] = sprite_add(working_directory+"/graphics/decal/cave_opening/spr_cave_opening.png",0,0,1,100,100);
	if spr_decal_sprite[argument0] = -1
		{
		show_message("Loading of cave opening image failed.");
		}
	spr_cave_opening_sprite = spr_decal_sprite[argument0]
	var_decal_fade_rate[argument0] = 0; //0 doesn't make it fade!
	var_decal_alpha[argument0] = 1; 
	var_cave_opening_loaded = 1;
	}
	else
		{
		spr_decal_sprite[argument0] = spr_cave_opening_sprite;
		var_decal_fade_rate[argument0] = 0; //0 doesn't make it fade!
		var_decal_alpha[argument0] = 1;
		}