Blood: Fix shadows crashing when rendered in mirrors

This also increments numsectors when rendering fake mirror sector, as to avoid out of bounds crashes when calling engine functions related to mirror sector
nukeykt · Nov 5, 2024 · 76f3933 · 76f3933
1 parent a893571
commit 76f3933
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Showing 3 changed files with 28 additions and 4 deletions.
diff --git a/source/blood/src/mirrors.cpp b/source/blood/src/mirrors.cpp
@@ -35,6 +35,8 @@ Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
 #include "view.h"
 #include "warp.h"
 
+bool gMirrorDrawing;
+
 int mirrorcnt, mirrorsector, mirrorwall[4];
 
 typedef struct
@@ -85,6 +87,7 @@ void InitMirrors(void)
 #endif //  POLYMER
 
 #endif
+    gMirrorDrawing = false;
     mirrorcnt = 0;
     tilesiz[504].x = 0;
     tilesiz[504].y = 0;
@@ -360,6 +363,10 @@ void DrawMirrors(int x, int y, int z, fix16_t a, fix16_t horiz, int smooth, int
             {
             case 0:
             {
+                gMirrorDrawing = true;
+                const int bakNumsectors = numsectors;
+                if ((numsectors < kMaxSectors-1) && !VanillaMode())
+                    numsectors++; // needed for rendering else operations like getzrange will crash when checking mirror sector
                 int nWall = mirror[i].at4;
                 int nSector = sectorofwall(nWall);
                 walltype *pWall = &wall[nWall];
@@ -406,6 +413,8 @@ void DrawMirrors(int x, int y, int z, fix16_t a, fix16_t horiz, int smooth, int
                     TranslateMirrorColors(wall[nWall].shade, wall[nWall].pal);
                 pWall->nextwall = nNextWall;
                 pWall->nextsector = nNextSector;
+                numsectors = bakNumsectors;
+                gMirrorDrawing = false;
                 return;
             }
             case 1:
@@ -519,6 +528,7 @@ void MirrorLoadSave::Load(void)
     Read(&mirrorsector,sizeof(mirrorsector));
     Read(mirror, sizeof(mirror));
     Read(mirrorwall, sizeof(mirrorwall));
+    gMirrorDrawing = false;
     tilesiz[504].x = 0;
     tilesiz[504].y = 0;
 

diff --git a/source/blood/src/mirrors.h b/source/blood/src/mirrors.h
@@ -26,3 +26,5 @@ void InitMirrors(void);
 void sub_5571C(char mode);
 void sub_557C4(int x, int y, int interpolation);
 void DrawMirrors(int x, int y, int z, fix16_t a, fix16_t horiz, int smooth, int viewPlayer);
+
+extern bool gMirrorDrawing;
diff --git a/source/blood/src/view.cpp b/source/blood/src/view.cpp
@@ -2406,12 +2406,24 @@ tspritetype *viewAddEffect(int nTSprite, VIEW_EFFECT nViewEffect)
         pNSprite->z = getflorzofslope(pTSprite->sectnum, pNSprite->x, pNSprite->y);
         if (!VanillaMode()) // support better floor detection for shadows (detect fake floors/allows ROR traversal)
         {
-            int ceilZ, ceilHit, floorZ, floorHit;
-            GetZRangeAtXYZ(pTSprite->x, pTSprite->y, pTSprite->z, pTSprite->sectnum, &ceilZ, &ceilHit, &floorZ, &floorHit, pTSprite->clipdist<<2, CLIPMASK0, PARALLAXCLIP_CEILING|PARALLAXCLIP_FLOOR);
-            if (((floorHit&0xc000) == 0xc000) && spriRangeIsFine(floorHit&0x3fff) && ((sprite[floorHit&0x3fff].cstat & (CSTAT_SPRITE_BLOCK|CSTAT_SPRITE_ALIGNMENT_FLOOR|CSTAT_SPRITE_INVISIBLE)) == (CSTAT_SPRITE_BLOCK|CSTAT_SPRITE_ALIGNMENT_FLOOR))) // if there is a fake floor under us, use fake floor as the shadow position
+            char bHitFakeFloor = 0;
+            short nFakeFloorSprite;
+            if (spriRangeIsFine(pTSprite->owner) && (!gMirrorDrawing || numsectors < kMaxSectors-1)) // don't attempt to check for fake floors if we hit max sectors for mirror sector
+            {
+                spritetype *pSprite = &sprite[pTSprite->owner];
+                int bakCstat = pSprite->cstat;
+                pSprite->cstat &= ~257;
+                int ceilZ, ceilHit, floorZ, floorHit;
+                GetZRangeAtXYZ(pSprite->x, pSprite->y, pSprite->z, pSprite->sectnum, &ceilZ, &ceilHit, &floorZ, &floorHit, pSprite->clipdist<<2, CLIPMASK0, PARALLAXCLIP_CEILING|PARALLAXCLIP_FLOOR);
+                nFakeFloorSprite = floorHit&0x3fff;
+                if ((floorHit&0xc000) == 0xc000)
+                    bHitFakeFloor = (sprite[nFakeFloorSprite].cstat & (CSTAT_SPRITE_BLOCK|CSTAT_SPRITE_ALIGNMENT_FLOOR|CSTAT_SPRITE_INVISIBLE)) == (CSTAT_SPRITE_BLOCK|CSTAT_SPRITE_ALIGNMENT_FLOOR);
+                pSprite->cstat = bakCstat;
+            }
+            if (bHitFakeFloor) // if there is a fake floor under us, use fake floor as the shadow position
             {
                 int top, bottom;
-                GetSpriteExtents(&sprite[floorHit&0x3fff], &top, &bottom);
+                GetSpriteExtents(&sprite[nFakeFloorSprite], &top, &bottom);
                 pNSprite->z = top;
                 pNSprite->z--; // offset from fake floor so it isn't z-fighting when being rendered
             }