You can use this function to check and see if a sprite element exists on any given layer. You supply the layer ID (which you get when you create the layer using layer_create()) or the layer name (as a string - this will have a performance impact) and the sprite element ID (which you get when you create a sprite element using layer_background_create() or when you use the function layer_sprite_get_id()) and the function will return either true if the element exists, or false if it does not.NOTE: This function works within the scope of the current target room - by default the room in which the function is called - which can be set using the function layer_set_target_room().
Argument Description layer_id The unique ID value of the layer to target (or the layer name as a string) sprite_element_id The unique ID value of the sprite element to check
var lay_id = layer_get_id("Asset_Trees");
if layer_sprite_exists(lay_id, global.TreesSprites)
The above code checks the layer "Asset_trees" to see if the given sprite element exists and if it does, then it is destroyed (but not the layer).