Improved direct vertical aiming and height calculations (#1213)

* Fix autoaim for direct vertical aiming

* Increase autoaim range for direct vertical aiming

* Calculate `actualheight` from current sprite

* Use `actualheight` for lock-on crosshair

* Use `actualheight` for check/aim/shoot

* Remove unused `spriteheight`

* Revert "Fix autoaim for direct vertical aiming"

This reverts commit 3a82190a6a0806f2f031ff23ccf61381b1924279.

* Revert "Increase autoaim range for direct vertical aiming"

This reverts commit 6c0e819567bcd0518709146ba1e97fd53b0653db.

src/i_3dsound.c

@@ -173,13 +173,13 @@ static void CalcDistance(const mobj_t *listener, const mobj_t *source,
 
     // Treat monsters and projectiles as point sources.
     src->point_source = (source->thinker.function.v != (actionf_v)P_DegenMobjThinker &&
-                        source->info && source->info->actualheight);
+                        source->info && source->actualheight);
 
     if (src->point_source)
     {
         fixed_t adz;
         // Vertical distance is from player's view to middle of source's sprite.
-        src->z = source->z + (source->info->actualheight >> 1);
+        src->z = source->z + (source->actualheight >> 1);
         adz = abs((listener->player->viewz >> FRACBITS) - (src->z >> FRACBITS));
         CalcHypotenuse(distxy, adz, dist);
     }

src/info.h

@@ -1524,8 +1524,6 @@ typedef struct
     int bloodcolor;   // [FG] colored blood and gibs
     // DEHEXTRA
     mobjtype_t droppeditem; // mobj to drop after death
-    // [crispy] height of the spawnstate's first sprite in pixels
-    int	actualheight;
 } mobjinfo_t;
 
 #define NO_ALTSPEED -1

src/p_map.c

@@ -491,6 +491,13 @@ static boolean P_ProjectileImmune(mobj_t *target, mobj_t *source)
     );
 }
 
+// [FG] mobj or actual sprite height
+static const inline fixed_t thingheight (const mobj_t *const thing, const mobj_t *const cond)
+{
+  return (direct_vertical_aiming && cond && cond->player && thing->actualheight > thing->height) ?
+        thing->actualheight : thing->height;
+}
+
 static boolean PIT_CheckThing(mobj_t *thing) // killough 3/26/98: make static
 {
   fixed_t blockdist;
@@ -565,13 +572,9 @@ static boolean PIT_CheckThing(mobj_t *thing) // killough 3/26/98: make static
   if (tmthing->flags & MF_MISSILE || (tmthing->flags & MF_BOUNCES &&
 				      !(tmthing->flags & MF_SOLID)))
     {
-      // [crispy] mobj or actual sprite height
-      const fixed_t thingheight = (direct_vertical_aiming && tmthing->target && tmthing->target->player) ?
-        thing->info->actualheight : thing->height;
-
       // see if it went over / under
 
-      if (tmthing->z > thing->z + thingheight)
+      if (tmthing->z > thing->z + thingheight(thing, tmthing->target))
 	return true;    // overhead
 
       if (tmthing->z+tmthing->height < thing->z)
@@ -1487,7 +1490,7 @@ static boolean PTR_AimTraverse (intercept_t *in)
   // check angles to see if the thing can be aimed at
 
   dist = FixedMul(attackrange, in->frac);
-  thingtopslope = FixedDiv(th->z+th->height - shootz , dist);
+  thingtopslope = FixedDiv(th->z+thingheight(th, shootthing) - shootz , dist);
 
   if (thingtopslope < bottomslope)
     return true;    // shot over the thing
@@ -1615,12 +1618,7 @@ static boolean PTR_ShootTraverse(intercept_t *in)
   // check angles to see if the thing can be aimed at
 
   dist = FixedMul (attackrange, in->frac);
-  {
-  // [crispy] mobj or actual sprite height
-  const fixed_t thingheight = (direct_vertical_aiming && shootthing->player) ?
-    th->info->actualheight : th->height;
-  thingtopslope = FixedDiv (th->z+thingheight - shootz , dist);
-  }
+  thingtopslope = FixedDiv (th->z+thingheight(th, shootthing) - shootz , dist);
 
   if (thingtopslope < aimslope)
     return true;  // shot over the thing

src/p_mobj.c

@@ -108,6 +108,12 @@ boolean P_SetMobjState(mobj_t* mobj,statenum_t state)
   if (tempstate)
     Z_Free(tempstate);
 
+  // [FG] update object's actual height
+  if (ret)
+  {
+    mobj->actualheight = spritetopoffset[sprites[mobj->sprite].spriteframes[mobj->frame & FF_FRAMEMASK].lump[0]];
+  }
+
   return ret;
 }
 
@@ -883,28 +889,8 @@ mobj_t *P_SpawnMobj(fixed_t x, fixed_t y, fixed_t z, mobjtype_t type)
       mobj->intflags &= ~MIF_FLIP;
   }
 
-  // [crispy] height of the spawnstate's first sprite in pixels
-  if (!info->actualheight)
-  {
-    const spritedef_t *const sprdef = &sprites[mobj->sprite];
-
-    if (!sprdef->numframes || !(mobj->flags & (MF_SOLID|MF_SHOOTABLE)))
-    {
-      info->actualheight = info->height;
-    }
-    else
-    {
-      spriteframe_t *sprframe;
-      int lump;
-      patch_t *patch;
-
-      sprframe = &sprdef->spriteframes[mobj->frame & FF_FRAMEMASK];
-      lump = sprframe->lump[0];
-      patch = W_CacheLumpNum(lump + firstspritelump, PU_CACHE);
-
-      info->actualheight = SHORT(patch->height) << FRACBITS;
-    }
-  }
+  // [FG] initialize object's actual height
+  mobj->actualheight = spritetopoffset[sprites[st->sprite].spriteframes[st->frame & FF_FRAMEMASK].lump[0]];
 
   P_AddThinker(&mobj->thinker);
 

src/p_mobj.h

@@ -379,6 +379,9 @@ typedef struct mobj_s
 
     // [FG] colored blood and gibs
     int bloodcolor;
+
+    // [FG] height of the sprite in pixels
+    int actualheight;
 } mobj_t;
 
 // External declarations (fomerly in p_local.h) -- killough 5/2/98

src/p_saveg.c

@@ -497,6 +497,9 @@ static void saveg_read_mobj_t(mobj_t *str)
     {
       str->bloodcolor = 0;
     }
+
+    // [FG] height of the sprite in pixels
+    str->actualheight = spritetopoffset[sprites[str->sprite].spriteframes[str->frame & FF_FRAMEMASK].lump[0]];
 }
 
 static void saveg_write_mobj_t(mobj_t *str)

src/r_things.c

@@ -648,7 +648,7 @@ void R_ProjectSprite (mobj_t* thing)
     HU_UpdateCrosshairLock
     (
       BETWEEN(0, viewwidth  - 1, (centerxfrac + FixedMul(txc, xscale)) >> FRACBITS),
-      BETWEEN(0, viewheight - 1, (centeryfrac + FixedMul(viewz - interpz - crosshair_target->height/2, xscale)) >> FRACBITS)
+      BETWEEN(0, viewheight - 1, (centeryfrac + FixedMul(viewz - interpz - crosshair_target->actualheight/2, xscale)) >> FRACBITS)
     );
 
     crosshair_target = NULL; // Don't update it again until next tic