Getzrange

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getzrange <x> <y> <z> <sector> <ceilingz> <ceilinghit> <floorz> <floorhit> <walldist> <clipmask>

Given a starting point and its containing sector, calculate (1) the z coordinates of (2) the objects that would be first hit by a quadratic, floor-aligned sprite pointing parallel to the grid and having side length 2*<walldist>, when travelling in a straight line up- and downwards (respectively for <ceiling...> and <floor...>). The <clipmask> is specified in the same fashion as in hitscan.

<ceilinghit> and <floorhit> can take the following values:

  • 16384 + sectnum, if a ceiling or floor was hit first
  • 49152 + spritenum, if a sprite was hit first

The behaviour in corner cases (sectnum invalid, x/y/z not in sectnum, etc.) should not be relied upon.

Example: Checking for spritebridges

The state below checks if the current actor is on a spritebridge, and if so, "returns" the id of that sprite.

// assumption: relevant variables are declared
defstate check_spritebridge
	 geta[].x my_x
	 geta[].y my_y
	 geta[].z my_z
	 geta[].sectnum sectnum
	 
	 getzrange my_x my_y my_z sectnum
		 ceilingz
		 ceilinghit
		 floorz
		 floorhit
		 256
 		 CLIPMASK0
		
	set outputSpriteId -1
	ifge floorhit 49152
	{
		sub floorhit 49152
		
		ifvarand sprite[floorhit].cstat 32
			set outputSpriteId floorhit
	}
       
       // outputSpriteId now contains either -1 if no spritebridge is detected, or the id of the spritebridge if there is
ends