[r3508] Projectiles "clip through" steps

[Xaser]

Just spotted an odd one: it appears that projectiles will 'leap' up steps now (possibly related to this fix?).

To reproduce, whip out the plasma gun on MAP01 and shoot at one of the lower steps and watch as they travel upward. The effect is even more pronounced if you fire at the light boxes in the window room. You'll see something like this:




A fun effect, but not exactly desirable in the general case.

[Gez]

Best screenshot:



I can fix the bug by changing the checked flag:

Code: Select all

		if (!(thing->flags & MF_TELEPORT) && !(thing->flags3 & MF3_FLOORHUGGER))
		{
			if (tm.floorz-thing->z > thing->MaxStepHeight)
			{ // too big a step up
				goto pushline;
			}
			else if ((thing->flags & MF_MISSILE)&& !(thing->flags6 && MF6_STEPMISSILE) && tm.floorz > thing->z)
			{ // [RH] Don't let normal missiles climb steps
				goto pushline;
			}
			else if (thing->z < tm.floorz)
			{ // [RH] Check to make sure there's nothing in the way for the step up
				fixed_t savedz = thing->z;
				bool good;
				thing->z = tm.floorz;
				good = P_TestMobjZ (thing);
				thing->z = savedz;
				if (!good)
				{
					goto pushline;
				}
				if (thing->flags6 & MF6_STEPMISSILE)
				{
					thing->z = tm.floorz;
					// If moving down, cancel vertical component of the velocity
					if (thing->velz < 0)
					{
						thing->velz = 0;
					}
				}
			}
		}

Fix contained in GZDoom 1341.

[NightFright]

And I was starting to wonder why all of a sudden my plasmaballs are able to travel up stairs...

[Edward-san]

About this, fire a rocket to the stairs, freeze, go to the stairs, unfreeze, dead!

[Gez]

What do you mean? You impact on your own rockets now?

[NightFright]

But hey, this is an awesome cheat. You stand under a window, shoot straight forward, the rocket would travel up automatically, through the window, then down again (or it stays up in the air?) and hit anyone on the other side. Better then any mouselook, jumping or hack could ever do.

[Gez]

Not down again, no.

[Edward-san]

What do you mean? You impact on your own rockets now?

Yeah (before the new fix btw).