Taunt or Bug?

Check out...

The code contains a collision detection routine that can report the proximity of objects to jumpman.  This same routine is used by both the "death-collision" routine and "jumped-for-points" routine.  This works well since the things that cause death to jumpman also can be jumped over for points (barrels, fireballs).  Now, in order to have jumpman die when he collides with the Kong graphics, two invisible objects (a black square which is invisible against a black background) were added near Kong's feet.  The collision routine was modified to include these two invisible objects when checking for a collision.  This achieved the desired death collision with Kong, but it also meant that now these objects were included when checking for jumped-over points. 

The original thinking may have been that the death collision would occur before the jumped over points.  And this should have been true.  Since the size that the invisible objects were assigned was the maximum of 16x16, there really is no way for jumpman to clear the object without touching it.  Thus he should have died well before the points were awarded.  But I think the problem happened later when they increased the "jump zone" after they found out that sometimes barrels were jumped over (with a straight up jump) but they weren't registering as points.

The object width that was used for jumpman when detecting a death collision is 8 (4x2).
The object width that was used for jumpman when detecting jump-over points is 10 (5x2).

As you can see, that gives jumpman an extra 1 pixel margin on either side of him that he can register points in before he's involved in a death collision. 

And if you think about it, the taunt jump isn't really jumping "over" anything--it's just a jump straight into the air.

Incidentally a similar death collision occurs at the oilcan on the girders level.  If you try to jump over the oilcan when the fire is there, you will hit the fire and die.  If you try to jump over it before the fire starts, you will still die.  I think this is another example of unintended collisions. 

back to D2K