sprite_collision_mask(ind, sepmasks, bboxmode, bbleft, bbtop, bbright, bbbottom, kind, tolerance);
|ind||The index of the sprite to set the bounding box of.|
|sepmasks||Whether to create collision masks for each sub-image of the sprite (true), or one mask for all (false).|
|bboxmode||What kind of bounding box to use. 0=automatic, 1=full image, 2=user defined.|
|bbleft||The maximum left position of the bounding box.|
|bbtop||The maximum top position of the bounding box.|
|bbright||The maximum right position of the bounding box.|
|bbbottom||The maximum bottom position of the bounding box.|
|kind||The kind of mask (0=precise, 1=bounding box, 2=disk, 3=diamond).|
|tolerance||Indicates the tolerance in the transparency value (0=no tolerance, 255=full tolerance).|
With this function you can set the type of collision mask that a
sprite should have. If you select either automatic, or precise,
then the bounding box values can be set to 0, however for a user
defined mask you will have to set these values.
The bounding box is always a relative value, based on the (0,0) position being the top left corner of the sprite (irrespective of the x and y origin).
The kind of mask sets the general shape for the mask itself, although if you have a user defined bounding box, you may end up with a "cut off" mask that is not complete.
Finally, tolerance is used to define how precise the precise mask is, with a tolerance of 0 meaning that the mask will follow every single pixel that has a transparency over 0, while other values will shift the collision mask perimeter depending on the transparency of the pixels.
NOTE: This function is only useful for bitmap sprites and will not work with SWF or JSON (Spine) sprites.
NOTE: This function will only work on duplicated sprites and not directly on pre-made resources. you can duplicate sprites using the function sprite_duplicate.
spr = sprite_add("player_5.png", 16, true, true, 0,
sprite_collision_mask(spr, true, 1, 0, 0, 0, 0, 0, 0);
The above code loads a sprite from an external source and stores the new index in the variable "spr". The code then sets the new sprite to have a precise collision mask for each of its sub-images.