Show a message box on errors in release mode on Windows.

Bug report:
If you use a staircase on the same frame that a door opens,
enemy spawns shift into different rooms and doors start
acting funny until you leave the dungeon or use the mirror.

ancilla.c

@@ -4753,12 +4753,10 @@ endif_5:
   }
 }
 
-void AncillaAdd_SomariaBlock(uint8 type, uint8 y) {  // 88e078
+int AncillaAdd_SomariaBlock(uint8 type, uint8 y) {  // 88e078
   int k = AncillaAdd_AddAncilla_Bank08(type, y);
-  if (k < 0) {
-    Refund_Magic(4);
-    return;
-  }
+  if (k < 0)
+    return k;
   for (int j = 4; j >= 0; j--) {
     if (j == k || ancilla_type[j] != 0x2c)
       continue;
@@ -4771,7 +4769,7 @@ void AncillaAdd_SomariaBlock(uint8 type, uint8 y) {  // 88e078
       bitmask_of_dragstate = 0;
       link_speed_setting = 0;
     }
-    return;
+    return k;
   }
 
   Ancilla_Sfx3_Near(0x2a);
@@ -4804,6 +4802,7 @@ void AncillaAdd_SomariaBlock(uint8 type, uint8 y) {  // 88e078
     Ancilla_SetY(k, link_y_coord + kCaneOfSomaria_Y[j]);
     SomariaBlock_CheckForTransitTile(k);
   }
+  return k;
 }
 
 void SomariaBlock_CheckForTransitTile(int k) {  // 88e191
@@ -5378,7 +5377,10 @@ void Ancilla3A_BigBombExplosion(int k) {  // 88f18d
   }
   if (ancilla_item_to_link[k] == 3 && ancilla_arr3[k] == 1) {
     Bomb_CheckForDestructibles(Ancilla_GetX(k), Ancilla_GetY(k), 0); // r14?
-    follower_indicator = 0;
+
+    // Changed so this is reset elsewhere
+    if (!(enhanced_features0 & kFeatures0_MiscBugFixes))
+      follower_indicator = 0;
   }
 }
 
@@ -6087,7 +6089,7 @@ void AncillaAdd_SomariaPlatformPoof(int k) {  // 898dd2
   Player_TileDetectNearby();
 }
 
-void AncillaAdd_SuperBombExplosion(uint8 a, uint8 y) {  // 898df9
+int AncillaAdd_SuperBombExplosion(uint8 a, uint8 y) {  // 898df9
   int k = Ancilla_AddAncilla(a, y);
   if (k >= 0) {
     ancilla_R[k] = 0;
@@ -6101,6 +6103,7 @@ void AncillaAdd_SuperBombExplosion(uint8 a, uint8 y) {  // 898df9
     int x = tagalong_x_lo[j] | tagalong_x_hi[j] << 8;
     Ancilla_SetXY(k, x + 8, y + 16);
   }
+  return k;
 }
 
 void ConfigureRevivalAncillae() {  // 898e4e

ancilla.h

@@ -173,7 +173,7 @@ void Ancilla31_ByrnaSpark(int k);
 void Ancilla_SwordBeam(int k);
 void Ancilla0D_SpinAttackFullChargeSpark(int k);
 void Ancilla27_Duck(int k);
-void AncillaAdd_SomariaBlock(uint8 type, uint8 y);
+int AncillaAdd_SomariaBlock(uint8 type, uint8 y);
 void SomariaBlock_CheckForTransitTile(int k);
 int Ancilla_CheckBasicSpriteCollision(int k);
 bool Ancilla_CheckBasicSpriteCollision_Single(int k, int j);
@@ -219,7 +219,7 @@ void AncillaAdd_ChargedSpinAttackSparkle();
 void AncillaAdd_ExplodingWeatherVane(uint8 a, uint8 y);
 void AncillaAdd_CutsceneDuck(uint8 a, uint8 y);
 void AncillaAdd_SomariaPlatformPoof(int k);
-void AncillaAdd_SuperBombExplosion(uint8 a, uint8 y);
+int AncillaAdd_SuperBombExplosion(uint8 a, uint8 y);
 void ConfigureRevivalAncillae();
 void AncillaAdd_LampFlame(uint8 a, uint8 y);
 void AncillaAdd_MSCutscene(uint8 a, uint8 y);

dungeon.c

@@ -2052,13 +2052,14 @@ void RoomBounds_SubA(RoomBounds *r) {
 }
 
 void Dungeon_StartInterRoomTrans_Left() {
+  assert(submodule_index == 0);
   link_quadrant_x ^= 1;
   Dungeon_AdjustQuadrant();
   RoomBounds_SubA(&room_bounds_x);
   Dung_SaveDataForCurrentRoom();
   DungeonTransition_AdjustCamera_X(link_quadrant_x ^ 1);
   HandleEdgeTransition_AdjustCameraBoundaries(3);
-  submodule_index++;
+  submodule_index = 1;
   if (link_quadrant_x) {
     RoomBounds_SubB(&room_bounds_x);
     BYTE(dungeon_room_index_prev) = dungeon_room_index;
@@ -2072,7 +2073,7 @@ void Dungeon_StartInterRoomTrans_Left() {
       }
       dungeon_room_index--;
     }
-    submodule_index += 1;
+    submodule_index = 2;
     if (room_transitioning_flags & 1) {
       link_is_on_lower_level ^= 1;
       link_is_on_lower_level_mirror = link_is_on_lower_level;
@@ -2091,13 +2092,14 @@ void Dung_StartInterRoomTrans_Left_Plus() {
 }
 
 void Dungeon_StartInterRoomTrans_Up() {
+  assert(submodule_index == 0);
   link_quadrant_y ^= 2;
   Dungeon_AdjustQuadrant();
   RoomBounds_SubA(&room_bounds_y);
   Dung_SaveDataForCurrentRoom();
   DungeonTransition_AdjustCamera_Y(link_quadrant_y ^ 2);
   HandleEdgeTransition_AdjustCameraBoundaries(1);
-  submodule_index++;
+  submodule_index = 1;
   if (link_quadrant_y) {
     RoomBounds_SubB(&room_bounds_y);
     BYTE(dungeon_room_index_prev) = dungeon_room_index;
@@ -2119,7 +2121,7 @@ void Dungeon_StartInterRoomTrans_Up() {
       Dungeon_AdjustAfterSpiralStairs();
     }
     BYTE(dungeon_room_index) -= 0x10;
-    submodule_index += 1;
+    submodule_index = 2;
     if (room_transitioning_flags & 1) {
       link_is_on_lower_level ^= 1;
       link_is_on_lower_level_mirror = link_is_on_lower_level;
@@ -2133,13 +2135,14 @@ void Dungeon_StartInterRoomTrans_Up() {
 }
 
 void Dungeon_StartInterRoomTrans_Down() {
+  assert(submodule_index == 0);
   link_quadrant_y ^= 2;
   Dungeon_AdjustQuadrant();
   RoomBounds_AddA(&room_bounds_y);
   Dung_SaveDataForCurrentRoom();
   DungeonTransition_AdjustCamera_Y(link_quadrant_y);
   HandleEdgeTransition_AdjustCameraBoundaries(0);
-  submodule_index++;
+  submodule_index = 1;
   if (!link_quadrant_y) {
     RoomBounds_AddB(&room_bounds_y);
     BYTE(dungeon_room_index_prev) = dungeon_room_index;
@@ -2153,7 +2156,7 @@ void Dungeon_StartInterRoomTrans_Down() {
       Dungeon_AdjustAfterSpiralStairs();
     }
     BYTE(dungeon_room_index) += 16;
-    submodule_index += 1;
+    submodule_index = 2;
     if (room_transitioning_flags & 1) {
       link_is_on_lower_level ^= 1;
       link_is_on_lower_level_mirror = link_is_on_lower_level;
@@ -4281,6 +4284,14 @@ void Dungeon_FlipCrystalPegAttribute() {  // 81c22a
 void Dungeon_HandleRoomTags() {  // 81c2fd
   if (!flag_skip_call_tag_routines) {
     Dungeon_DetectStaircase();
+
+    // Dungeon_DetectStaircase might change the submodule, so avoid
+    // calling the tag routines cause they could also change the submodule,
+    // causing items to spawn in incorrect locations cause link_x/y_coord gets
+    // out of sync if you enter a staircase exactly when a room tag triggers.
+    if (enhanced_features0 & kFeatures0_MiscBugFixes && submodule_index != 0)
+      return;
+
     g_ram[14] = 0;
     kDungTagroutines[dung_hdr_tag[0]](0);
     g_ram[14] = 1;
@@ -7958,13 +7969,14 @@ void HandleEdgeTransitionMovementEast_RightBy8() {  // 82b62e
 }
 
 void Dungeon_StartInterRoomTrans_Right() {  // 82b63a
+  assert(submodule_index == 0);
   link_quadrant_x ^= 1;
   Dungeon_AdjustQuadrant();
   RoomBounds_AddA(&room_bounds_x);
   Dung_SaveDataForCurrentRoom();
   DungeonTransition_AdjustCamera_X(link_quadrant_x);
   HandleEdgeTransition_AdjustCameraBoundaries(2);
-  submodule_index++;
+  submodule_index = 1;
   if (!link_quadrant_x) {
     RoomBounds_AddB(&room_bounds_x);
     BYTE(dungeon_room_index_prev) = dungeon_room_index;
@@ -7978,7 +7990,7 @@ void Dungeon_StartInterRoomTrans_Right() {  // 82b63a
       }
       dungeon_room_index += 1;
     }
-    submodule_index += 1;
+    submodule_index = 2;
     if (room_transitioning_flags & 1) {
       link_is_on_lower_level ^= 1;
       link_is_on_lower_level_mirror = link_is_on_lower_level;
@@ -8591,7 +8603,7 @@ void HandleLinkOnSpiralStairs() {  // 87f2c1
       link_actual_vel_x = 2;
     }
   }
-  LinkHop_FindArbitraryLandingSpot();
+  Link_MovePosition();
   Link_HandleMovingAnimation_StartWithDash();
   if (!link_timer_push_get_tired && sign8(--countdown_timer_for_staircases)) {
     countdown_timer_for_staircases = 0;
@@ -8630,7 +8642,7 @@ void SpiralStairs_FindLandingSpot() {  // 87f391
     link_actual_vel_x = -4, link_actual_vel_y = 2;
   if (some_animation_timer_steps == 2)
     link_actual_vel_x = 0, link_actual_vel_y = 16;
-  LinkHop_FindArbitraryLandingSpot();
+  Link_MovePosition();
   Link_HandleMovingAnimation_StartWithDash();
   if ((uint8)link_x_coord == (uint8)tiledetect_which_y_pos[1])
     some_animation_timer_steps = 2;

main.c

@@ -65,6 +65,9 @@ static int g_snes_width, g_snes_height;
 static int g_sdl_audio_mixer_volume = SDL_MIX_MAXVOLUME;
 
 void NORETURN Die(const char *error) {
+#if defined(NDEBUG) && defined(_WIN32)
+  SDL_ShowSimpleMessageBox(SDL_MESSAGEBOX_ERROR, kWindowTitle, error, NULL);
+#endif
   fprintf(stderr, "Error: %s\n", error);
   exit(1);
 }
@@ -123,13 +126,12 @@ static SDL_HitTestResult HitTestCallback(SDL_Window *win, const SDL_Point *area,
          (SDL_GetModState() & KMOD_CTRL) != 0 ? SDL_HITTEST_DRAGGABLE : SDL_HITTEST_NORMAL;
 }
 
-static bool RenderScreenWithPerf(uint8 *pixel_buffer, size_t pitch, uint32 render_flags) {
-  bool rv;
+static void RenderScreenWithPerf(uint8 *pixel_buffer, size_t pitch, uint32 render_flags) {
   if (g_display_perf || g_config.display_perf_title) {
     static float history[64], average;
     static int history_pos;
     uint64 before = SDL_GetPerformanceCounter();
-    rv = ZeldaDrawPpuFrame(pixel_buffer, pitch, render_flags);
+    ZeldaDrawPpuFrame(pixel_buffer, pitch, render_flags);
     uint64 after = SDL_GetPerformanceCounter();
     float v = (double)SDL_GetPerformanceFrequency() / (after - before);
     average += v - history[history_pos];
@@ -137,9 +139,8 @@ static bool RenderScreenWithPerf(uint8 *pixel_buffer, size_t pitch, uint32 rende
     history_pos = (history_pos + 1) & 63;
     g_curr_fps = average * (1.0f / 64);
   } else {
-    rv = ZeldaDrawPpuFrame(pixel_buffer, pitch, render_flags);
+    ZeldaDrawPpuFrame(pixel_buffer, pitch, render_flags);
   }
-  return rv;
 }
 
 // Go some steps up and find zelda3.ini
@@ -481,30 +482,27 @@ static void RenderNumber(uint8 *dst, size_t pitch, int n, bool big) {
 }
 
 static void RenderScreen(SDL_Window *window, SDL_Renderer *renderer, SDL_Texture *texture, bool fullscreen) {
-  uint8* pixels = NULL;
+  uint8 *pixels = 0;
   int pitch = 0;
+  int render_scale = PpuGetCurrentRenderScale(g_zenv.ppu, g_ppu_render_flags);
+  SDL_Rect src_rect = { 0, 0, g_snes_width * render_scale >> 1, g_snes_height * render_scale >> 1};
+
   uint64 t0 = SDL_GetPerformanceCounter();
-  if(SDL_LockTexture(texture, NULL, (void**)&pixels, &pitch) != 0) {
+  if(SDL_LockTexture(texture, &src_rect, (void**)&pixels, &pitch) != 0) {
     printf("Failed to lock texture: %s\n", SDL_GetError());
     return;
   }
   uint64 t1 = SDL_GetPerformanceCounter();
-  bool hq = RenderScreenWithPerf(pixels, pitch, g_ppu_render_flags);
+  RenderScreenWithPerf(pixels, pitch, g_ppu_render_flags);
   if (g_display_perf) {
-    RenderNumber(pixels + (pitch * 2 << hq), pitch, g_curr_fps, hq);
-  }
-  if (g_config.display_perf_title) {
-    char title[60];
-    snprintf(title, sizeof(title), "%s | FPS: %d", kWindowTitle, g_curr_fps);
-    SDL_SetWindowTitle(window, title);
+    RenderNumber(pixels + pitch * render_scale, pitch, g_curr_fps, render_scale == 4);
   }
   uint64 t2 = SDL_GetPerformanceCounter();
   SDL_UnlockTexture(texture);
   uint64 t3 = SDL_GetPerformanceCounter();
   SDL_RenderClear(renderer);
   uint64 t4 = SDL_GetPerformanceCounter();
-  SDL_Rect src_rect = { 0, 0, g_snes_width, g_snes_height };
-  SDL_RenderCopy(renderer, texture, hq ? NULL : &src_rect, NULL);
+  SDL_RenderCopy(renderer, texture, &src_rect, NULL);
   uint64 t5 = SDL_GetPerformanceCounter();
 
   double f = 1e3 / (double)SDL_GetPerformanceFrequency();
@@ -516,7 +514,11 @@ static void RenderScreen(SDL_Window *window, SDL_Renderer *renderer, SDL_Texture
     (t5 - t4) * f
   );
 
-
+  if (g_config.display_perf_title) {
+    char title[60];
+    snprintf(title, sizeof(title), "%s | FPS: %d", kWindowTitle, g_curr_fps);
+    SDL_SetWindowTitle(window, title);
+  }
 }
 
 static void HandleCommand_Locked(uint32 j, bool pressed);
@@ -743,7 +745,7 @@ static void LoadAssets() {
   uint8 *data = ReadFile("tables/zelda3_assets.dat", &length);
   if (!data)
     data = ReadFile("zelda3_assets.dat", &length);
-  if (!data) Die("Failed to read zelda3_assets.dat");
+  if (!data) Die("Failed to read zelda3_assets.dat. Please see the README for information about how you get this file.");
 
   static const char kAssetsSig[] = { kAssets_Sig };
 

messaging.c

@@ -2220,6 +2220,12 @@ void CopySaveToWRAM() {  // 8ccfbb
   word_7E021F = 0x7f;
   word_7E0221 = 0xffff;
 
+  // If you save / quit in the middle of a mosaic effect, such as
+  // being electrocuted by a buzz blob, the resumed game will skip
+  // the location prompt and start in the sanctuary.
+  if (enhanced_features0 & kFeatures0_MiscBugFixes)
+    mosaic_level = 0;
+
   hud_var1 = 128;
   main_module_index = 5;
   submodule_index = 0;

player.c

@@ -242,14 +242,20 @@ void PlayerHandler_00_Ground_3() {  // 8781a0
       Link_HandleYItem();
       if (sram_progress_indicator != 0) {
         Link_HandleSwordCooldown();
-        if (link_player_handler_state == 3) {
-          link_x_vel = link_y_vel = 0;
-          goto getout_dostuff;
-        }
       }
     }
   }
 
+  // Ensure we're not handling potions. Things further
+  // down don't assume this and change the module indexes randomly.
+  // Also check for spin attack for some reason.
+  if ((enhanced_features0 & kFeatures0_MiscBugFixes) && main_module_index == 14 && submodule_index != 2 ||
+      link_player_handler_state == 3) {
+    link_x_vel = link_y_vel = 0;
+    goto getout_dostuff;
+  }
+
+
   Link_HandleCape_passive_LiftCheck();
   if (link_incapacitated_timer) {
     link_moving_against_diag_tile = 0;
@@ -737,7 +743,7 @@ lbl_jump_into_middle:
     if ((link_direction & 0xc) == 0)
       link_actual_vel_y = 0;
   }
-  LinkHop_FindArbitraryLandingSpot(); // not
+  Link_MovePosition(); // not
 timer_running:
   if (link_player_handler_state != 6) {
     Link_HandleCardinalCollision(); // not
@@ -791,7 +797,7 @@ void LinkHop_HoppingSouthOW() {  // 87894e
   link_actual_vel_z_copy = link_actual_vel_z_copy_mirror;
   link_z_coord = link_z_coord_mirror;
   link_actual_vel_z -= 2;
-  LinkHop_FindArbitraryLandingSpot();
+  Link_MovePosition();
   if (sign8(link_actual_vel_z)) {
     if (link_actual_vel_z < 0xa0)
       link_actual_vel_z = 0xa0;
@@ -827,7 +833,7 @@ void LinkState_HandlingJump() {  // 878a05
   link_actual_vel_z_copy = link_actual_vel_z_copy_mirror;
   BYTE(link_z_coord) = link_z_coord_mirror;
   link_actual_vel_z -= 2;
-  LinkHop_FindArbitraryLandingSpot();
+  Link_MovePosition();
   if (sign8(link_actual_vel_z)) {
     if (link_actual_vel_z < 0xa0)
       link_actual_vel_z = 0xa0;
@@ -1014,7 +1020,7 @@ finish:
 void LinkState_HoppingDiagonallyUpOW() {  // 878dc6
   draw_water_ripples_or_grass = 0;
   Player_ChangeZ(2);
-  LinkHop_FindArbitraryLandingSpot();
+  Link_MovePosition();
   if (sign8(link_z_coord)) {
     Link_SplashUponLanding();
     if (link_player_handler_state != kPlayerState_Swimming && !link_is_in_deep_water)
@@ -1041,9 +1047,15 @@ void LinkState_HoppingDiagonallyDownOW() {  // 878e15
     LinkHop_FindLandingSpotDiagonallyDown();
     link_x_coord = old_x;
 
-    static const uint8 kLedgeVelX[] = { 4, 4, 4, 10, 10, 10, 11, 18, 18, 18, 20, 20, 20, 20, 22, 22, 26, 26, 26, 26, 28, 28, 28, 28 };
+    static const uint8 kLedgeVelX[] = { 
+      4, 4, 4, 10, 10, 10, 11, 18,
+      18, 18, 20, 20, 20, 20, 22, 22,
+      26, 26, 26, 26, 28, 28, 28, 28
+    };
 
-    int8 velx = kLedgeVelX[(uint16)(link_y_coord - link_y_coord_original) >> 3];
+    int t = (uint16)(link_y_coord - link_y_coord_original);
+    // Fix out of bounds read
+    int8 velx = kLedgeVelX[IntMin(t >> 3, 23)];
     link_actual_vel_x = (dir != 2) ? velx : -velx;
     if (!player_is_indoors)
       link_is_on_lower_level = 2;
@@ -1359,7 +1371,12 @@ void LinkState_Pits() {  // 8792d3
   } else {
     if (!link_is_running)
       goto aux_state;
-    if (link_countdown_for_dash) {
+    // If you use a turbo controller to perfectly spam the dash button,
+    // the check for Link being in a hole is endlessly skipped and you
+    // can levitate across chasms.
+    // Fix this by ensuring that the dash button is held down before proceeding to the dash state.
+    if (link_countdown_for_dash &&
+        (!(enhanced_features0 & kFeatures0_MiscBugFixes) || (joypad1L_last & 0x80))) {
       LinkState_Dashing();
       return;
     }
@@ -1444,6 +1461,8 @@ endif_1:
     ApplyLinksMovementToCamera();
     return;
   }
+
+  // Initiate fall down
   if (player_near_pit_state != 2) {
     if (link_item_moon_pearl) {
       link_need_for_poof_for_transform = 0;
@@ -2736,7 +2755,7 @@ void LinkState_UsingQuake() {  // 87a6d6
     BYTE(link_z_coord) = link_z_coord_mirror;
     link_auxiliary_state = 2;
     Player_ChangeZ(2);
-    LinkHop_FindArbitraryLandingSpot();
+    Link_MovePosition();
     link_actual_vel_z_mirror = link_actual_vel_z;
     link_actual_vel_z_copy_mirror = link_actual_vel_z_copy;
     BYTE(link_z_coord_mirror) = link_z_coord;
@@ -3144,7 +3163,7 @@ void LinkState_Hookshotting() {  // 87ab7c
   }
   return;
 loc_87AD49:
-  LinkHop_FindArbitraryLandingSpot();
+  Link_MovePosition();
   TileDetect_MainHandler(5);
   if (player_is_indoors) {
     uint8 x = tiledetect_vertical_ledge >> 4 | tiledetect_vertical_ledge | detection_of_ledge_tiles_horiz_uphoriz;
@@ -3197,7 +3216,9 @@ void LinkItem_Cape() {  // 87adc1
     link_direction &= ~0xf;
     if (!--cape_decrement_counter) {
       cape_decrement_counter = kCapeDepletionTimers[link_magic_consumption];
-      if (!--link_magic_power) {
+      // Avoid magic underflow if an anti-fairy consumes magic.
+      if (link_magic_power == 0 && (enhanced_features0 & kFeatures0_MiscBugFixes) ||
+          !--link_magic_power) {
         Link_ForceUnequipCape();
         return;
       }
@@ -3260,15 +3281,30 @@ void LinkItem_CaneOfSomaria() {  // 87aec0
     if (player_on_somaria_platform || is_standing_in_doorway || !CheckYButtonPress())
       return;
     int i = 4;
+    bool did_charge_magic = false;
+
     while (ancilla_type[i] != 0x2c) {
       if (--i < 0) {
-        if (!LinkCheckMagicCost(4))
+        if (!LinkCheckMagicCost(4)) {
+          // If you use the Cane of Somaria with an empty magic meter,
+          // then quickly switch to the mushroom or magic powder after
+          // the "no magic" prompt, you will automatically sprinkle magic powder
+          // despite pressing no button and having no magic.
+          if (enhanced_features0 & kFeatures0_MiscBugFixes)
+            goto out;
           return;
+        }
+        did_charge_magic = true;
         break;
       }
     }
     link_debug_value_2 = 1;
-    AncillaAdd_SomariaBlock(44, 1);
+    if (AncillaAdd_SomariaBlock(0x2c, 1) < 0) {
+      // If you use the Cane of Somaria while two bombs and the boomerang are active,
+      // magic will be refunded instead of used.
+      if (did_charge_magic || !(enhanced_features0 & kFeatures0_MiscBugFixes))
+        Refund_Magic(4);
+    }
     link_delay_timer_spin_attack = kRodAnimDelays[0];
     link_animation_steps = 0;
     player_handler_timer = 0;
@@ -3289,8 +3325,9 @@ void LinkItem_CaneOfSomaria() {  // 87aec0
   player_handler_timer = 0;
   link_delay_timer_spin_attack = 0;
   link_debug_value_2 = 0;
-  button_mask_b_y &= ~0x40;
   link_position_mode &= ~8;
+out:
+  button_mask_b_y &= ~0x40;
 }
 
 void LinkItem_CaneOfByrna() {  // 87af3e
@@ -3708,7 +3745,7 @@ reset_to_normal:
   if (!(link_direction & 0xc))
     link_actual_vel_y = 0;
 out:
-  LinkHop_FindArbitraryLandingSpot();
+  Link_MovePosition();
 out2:
   Link_HandleCardinalCollision();
   HandleIndoorCameraAndDoors();
@@ -5099,11 +5136,17 @@ void StartMovementCollisionChecks_X_HandleOutdoors() {  // 87c8e9
     return;
   } // endif_8
 
-  if ((R14 & 2) == 0 && (R12 & 5) != 0 && (!link_is_running || (link_direction_facing & 4))) {
-    FlagMovingIntoSlopes_X();
-    if ((link_moving_against_diag_tile & 0xf) != 0)
-      return;
-  }  // endif_9
+  // If force facing down (hold B button), while turboing on the Run key, we'll never
+  // reach FlagMovingIntoSlopes_X causing a Dash Buffering glitch.
+  // Fix by always calling it, not sure why you wouldn't always want to call it.
+  if ((R14 & 2) == 0 && (R12 & 5) != 0) {
+    bool skip_check = link_is_running && !(link_direction_facing & 4);
+    if (!skip_check || (enhanced_features0 & kFeatures0_MiscBugFixes)) {
+      FlagMovingIntoSlopes_X();
+      if ((link_moving_against_diag_tile & 0xf) != 0)
+        return;
+    }  // endif_9
+  }
 
   link_moving_against_diag_tile = 0;
 
@@ -5214,8 +5257,9 @@ void Link_HandleDiagonalKickback() {  // 87ccab
     static const int8 x1[] = { 0, -1, -1, -1, -2, -2, -2, -3, -3, -3 };
     link_x_coord += sign8(link_x_vel) ? x1[-(int8)link_x_vel] : x0[link_x_vel];
 
-    static const int8 y0[] = { 0, 0, 0, 1, 1, 1, 2, 2, 2, 3 };
-    static const int8 y1[] = { 0, 1, 1, 2, 2, 2, 3, 3, 3, 3 };
+    static const int8 y0[10] = { 0, 0, 0, 1, 1, 1, 2, 2, 2, 3 };
+    // Bug in zelda, might read index 15
+    static const int8 y1[16] = { 0, 1, 1, 2, 2, 2, 3, 3, 3, 3, 0xa5, 0x30, 0xf0, 0x04, 0xa5, 0x31 };
     link_y_coord += sign8(link_y_vel) ? y1[-(int8)link_y_vel] : y0[link_y_vel];
   } else {
 noHorizOrNoVertical:
@@ -5511,12 +5555,25 @@ void FlagMovingIntoSlopes_Y() {  // 87e076
   if (tiledetect_diagonal_tile & 5) {
     int8 ym = tiledetect_which_y_pos[0] & 7;
 
-    if (!(tiledetect_diag_state & 2)) {
-      ym = 8 - ym;
+    if (enhanced_features0 & kFeatures0_MiscBugFixes) {
+      if (tiledetect_diag_state & 2) {
+        ym = -ym;
+      } else {
+        ym = kAvoidJudder1[o] - (8 - ym);
+      }
     } else {
-      ym += 8;
+      // This code is bad because it could cause the player
+      // to move up to 15 pixels, causing an array out bounds read.
+      // Not sure how it works, but changed it to look more like the X version.
+      if (!(tiledetect_diag_state & 2)) {
+        ym = 8 - ym; // 0 to 8
+      } else {
+        ym += 8; // 8 to 15
+      }
+      // -15 to 7
+      ym = kAvoidJudder1[o] - ym;
     }
-    ym = kAvoidJudder1[o] - ym;
+
     if (link_y_vel == 0)
       return;
     if (sign8(link_y_vel))
@@ -5548,12 +5605,9 @@ void FlagMovingIntoSlopes_X() {  // 87e112
     int8 xm = link_x_coord & 7;
 
     if (tiledetect_diag_state != 4 && tiledetect_diag_state != 6) {
-      o ^= 7;
       xm = -xm;
     } else {
-      xm -= 8;
-      xm = -xm;
-      xm = kAvoidJudder1[o] - xm;
+      xm = kAvoidJudder1[o] - (8 - xm);
     } // endif_5
     if (link_x_vel == 0)
       return;
@@ -5677,10 +5731,10 @@ void Link_HandleVelocity() {  // 87e245
   link_actual_vel_z = 0xff;
   link_z_coord = 0xffff;
   link_subpixel_z = 0;
-  LinkHop_FindArbitraryLandingSpot();
+  Link_MovePosition();
 }
 
-void LinkHop_FindArbitraryLandingSpot() {  // 87e370
+void Link_MovePosition() {  // 87e370
   uint16 x = link_x_coord, y = link_y_coord;
   link_y_coord_safe_return_lo = link_y_coord;
   link_y_coord_safe_return_hi = link_y_coord >> 8;
@@ -6015,6 +6069,14 @@ void HandleDoorTransitions() {  // 87e901
   link_x_page_movement_delta = 0;
   link_y_page_movement_delta = 0;
 
+  // Using a potion might have changed us into a different module, and the routines
+  // below just increment the submodule value, causing all kinds of havoc.
+  // There's an added return to catch the same behavior a bit up, but this one catches more cases,
+  // at the expense of link already having done his movement, so by returning here we might
+  // miss handling the door causing other kinds of issues.
+  if ((enhanced_features0 & kFeatures0_MiscBugFixes) && !(main_module_index == 7 && submodule_index == 0))
+    return;
+
   if (link_direction_last & 0xC && is_standing_in_doorway == 1) {
     if (link_direction_last & 4) {
       if (((t = link_y_coord + 28) & 0xfc) == 0)

player.h

@@ -207,7 +207,7 @@ void FlagMovingIntoSlopes_X();
 void Link_HandleRecoiling();
 void Player_HandleIncapacitated_Inner2();
 void Link_HandleVelocity();
-void LinkHop_FindArbitraryLandingSpot();
+void Link_MovePosition();
 void Link_HandleVelocityAndSandDrag(uint16 x, uint16 y);
 void HandleSwimStrokeAndSubpixels();
 void Player_SomethingWithVelocity_TiredOrSwim(uint16 xvel, uint16 yvel);

snes/ppu.c

@@ -122,10 +122,14 @@ void ppu_saveload(Ppu *ppu, SaveLoadFunc *func, void *ctx) {
   func(ctx, tmp, 123);
 }
 
-bool PpuBeginDrawing(Ppu *ppu, uint8_t *pixels, size_t pitch, uint32_t render_flags) {
+int PpuGetCurrentRenderScale(Ppu *ppu, uint32_t render_flags) {
+  bool hq = ppu->mode == 7 && !ppu->forcedBlank &&
+    (ppu->renderFlags & (kPpuRenderFlags_4x4Mode7 | kPpuRenderFlags_NewRenderer)) == (kPpuRenderFlags_4x4Mode7 | kPpuRenderFlags_NewRenderer);
+  return hq ? 4 : 2;
+}
+
+void PpuBeginDrawing(Ppu *ppu, uint8_t *pixels, size_t pitch, uint32_t render_flags) {
   ppu->renderFlags = render_flags;
-  bool hq = ppu->mode == 7 && !ppu->forcedBlank && 
-      (ppu->renderFlags & (kPpuRenderFlags_4x4Mode7 | kPpuRenderFlags_NewRenderer)) == (kPpuRenderFlags_4x4Mode7 | kPpuRenderFlags_NewRenderer);
   ppu->renderPitch = (uint)pitch;
   ppu->renderBuffer = pixels;
 
@@ -140,14 +144,12 @@ bool PpuBeginDrawing(Ppu *ppu, uint8_t *pixels, size_t pitch, uint32_t render_fl
     memset(&ppu->brightnessMult[32], ppu->brightnessMult[31], 31);
   }
 
-  if (hq) {
+  if (PpuGetCurrentRenderScale(ppu, ppu->renderFlags) == 4) {
     for (int i = 0; i < 256; i++) {
       uint32 color = ppu->cgram[i];
       ppu->colorMapRgb[i] = ppu->brightnessMult[color & 0x1f] << 16 | ppu->brightnessMult[(color >> 5) & 0x1f] << 8 | ppu->brightnessMult[(color >> 10) & 0x1f];
     }
   }
-  
-  return hq;
 }
 
 static inline void ClearBackdrop(PpuPixelPrioBufs *buf) {
@@ -833,7 +835,7 @@ static void PpuDrawBackgrounds(Ppu *ppu, int y, bool sub) {
       PpuDrawBackground_2bpp(ppu, y, sub, 2, 0xf200, 0x1200);
   } else {
     // mode 7
-    PpuDrawBackground_mode7(ppu, y, sub, 0xc0);
+    PpuDrawBackground_mode7(ppu, y, sub, 0xc000);
     if (ppu->lineHasSprites)
       PpuDrawSprites(ppu, y, sub, false);
   }

snes/ppu.h

@@ -135,7 +135,10 @@ void ppu_runLine(Ppu* ppu, int line);
 uint8_t ppu_read(Ppu* ppu, uint8_t adr);
 void ppu_write(Ppu* ppu, uint8_t adr, uint8_t val);
 void ppu_saveload(Ppu *ppu, SaveLoadFunc *func, void *ctx);
-bool PpuBeginDrawing(Ppu *ppu, uint8_t *buffer, size_t pitch, uint32_t render_flags);
+void PpuBeginDrawing(Ppu *ppu, uint8_t *buffer, size_t pitch, uint32_t render_flags);
+
+// Returns the current render scale, 1x = 256px, 2x=512px, 4x=1024px
+int PpuGetCurrentRenderScale(Ppu *ppu, uint32_t render_flags);
 
 void PpuSetMode7PerspectiveCorrection(Ppu *ppu, int low, int high);
 void PpuSetExtraSideSpace(Ppu *ppu, int left, int right, int bottom);

sprite_main.c

@@ -11804,6 +11804,12 @@ void Sprite_D8_Heart(int k) {  // 86cec0
   if (Sprite_ReturnIfInactive(k))
     return;
   Sprite_CheckAbsorptionByPlayer(k);
+
+  // Avoid calling Sprite_HandleAbsorptionByPlayer twice, it's called
+  // also from within Sprite_HandleDraggingByAncilla
+  if (sprite_state[k] == 0 && (enhanced_features0 & kFeatures0_MiscBugFixes))
+    return;
+
   if (Sprite_HandleDraggingByAncilla(k))
     return;
   Sprite_MoveXY(k);

tagalong.c

@@ -426,8 +426,23 @@ void Follower_NotFollowing() {  // 89a2b2
     Tagalong_Draw();
   } else {
     if (follower_indicator == 13 && !player_is_indoors && !super_bomb_indicator_unk2) {
-      AncillaAdd_SuperBombExplosion(0x3a, 0);
-      follower_dropped = 0;
+      // Fixed so we wait a little bit if we can't spawn the ancilla
+      if (AncillaAdd_SuperBombExplosion(0x3a, 0) >= 0) {
+        follower_dropped = 0;
+
+        // A ticking super bomb will cancel and teleport back to you as a follower if you do
+        // any of these at count 0: (1) change screen via walking, mirror, or bird travel
+        // (2) fill all ancillary slots
+        // (3) die with a bottled faerie.
+        // Fixed this by clearing the follower indicator here, instead of in the ancilla
+        // bomb code.
+        if (enhanced_features0 & kFeatures0_MiscBugFixes) {
+          follower_indicator = 0;
+          return;
+        }
+      } else {
+        super_bomb_indicator_unk1 = 1;
+      }
     }
     Follower_DoLayers();
   }
@@ -650,8 +665,11 @@ skip_first_sprites:
   if (pal == 7 && overworld_palette_swap_flag)
     pal = 0;
 
-  if (follower_indicator == 13 && super_bomb_indicator_unk2 == 1)
-    pal = (frame_counter & 7);
+  if (follower_indicator == 13) {
+    // Display colorful superbomb palette also on frame 0.
+    if (enhanced_features0 & kFeatures0_MiscBugFixes ? (super_bomb_indicator_unk2 <= 1) : (super_bomb_indicator_unk2 == 1))
+     pal = (frame_counter & 7);
+  }
 
   const TagalongSprXY *sprd = kTagalongDraw_SprXY + frame + (kTagalongDraw_Offs[follower_indicator] >> 3);
   const TagalongDmaFlags *sprf = kTagalongDmaAndFlags + frame;

zelda_cpu_infra.c

@@ -46,12 +46,14 @@ static void MakeSnapshot(Snapshot *s) {
   memcpy(s->ram, g_snes->ram, 0x20000);
   memcpy(s->sram, g_snes->cart->ram, g_snes->cart->ramSize);
   memcpy(s->vram, g_snes->ppu->vram, sizeof(uint16) * 0x8000);
+  memcpy(s->ram + 0x1DBA0, s->ram + 0x1B00, 224 * 2);  // hdma_table (partial)
 }
 
 static void MakeMySnapshot(Snapshot *s) {
   memcpy(s->ram, g_zenv.ram, 0x20000);
   memcpy(s->sram, g_zenv.sram, 0x2000);
   memcpy(s->vram, g_zenv.ppu->vram, sizeof(uint16) * 0x8000);
+  memcpy(s->ram + 0x1B00, s->ram + 0x1DBA0, 224 * 2);  // hdma_table (partial)
 }
 
 static void RestoreMySnapshot(Snapshot *s) {
@@ -105,10 +107,8 @@ static void VerifySnapshotsEq(Snapshot *b, Snapshot *a, Snapshot *prev) {
   memcpy(&b->ram[0x1f0d], &a->ram[0x1f0d], 0x3f - 0xd);
   memcpy(b->ram + 0x138, a->ram + 0x138, 256 - 0x38); // copy the stack over
 
-  memcpy(a->ram + 0x1DBA0, b->ram + 0x1DBA0, 240 * 2);  // hdma_table
-  memcpy(b->ram + 0x1B00, b->ram + 0x1DBA0, 224 * 2);  // hdma_table (partial)
-
   memcpy(a->ram + 0x1cc0, b->ram + 0x1cc0, 2);  // some leftover stuff in hdma table
+  memcpy(a->ram + 0x1dd60, b->ram + 0x1dd60, 16 * 2);  // some leftover stuff in hdma table
 
   if (memcmp(b->ram, a->ram, 0x20000)) {
     fprintf(stderr, "@%d: Memory compare failed (mine != theirs, prev):\n", frame_counter);
@@ -351,7 +351,7 @@ again_mine:
   VerifySnapshotsEq(&g_snapshot_mine, &g_snapshot_theirs, &g_snapshot_before);
 
   if (g_fail) {
-    //    g_fail = false;
+    g_fail = false;
     if (1) {
       RestoreMySnapshot(&g_snapshot_before);
       //SaveLoadSlot(kSaveLoad_Save, 0);

zelda_rtl.c

@@ -215,10 +215,10 @@ static void ConfigurePpuSideSpace() {
   PpuSetExtraSideSpace(g_zenv.ppu, extra_left, extra_right, extra_bottom);
 }
 
-bool ZeldaDrawPpuFrame(uint8 *pixel_buffer, size_t pitch, uint32 render_flags) {
+void ZeldaDrawPpuFrame(uint8 *pixel_buffer, size_t pitch, uint32 render_flags) {
   SimpleHdma hdma_chans[2];
 
-  bool rv = PpuBeginDrawing(g_zenv.ppu, pixel_buffer, pitch, render_flags);
+  PpuBeginDrawing(g_zenv.ppu, pixel_buffer, pitch, render_flags);
 
   dma_startDma(g_zenv.dma, HDMAEN_copy, true);
 
@@ -257,8 +257,6 @@ bool ZeldaDrawPpuFrame(uint8 *pixel_buffer, size_t pitch, uint32 render_flags) {
     SimpleHdma_DoLine(&hdma_chans[0]);
     SimpleHdma_DoLine(&hdma_chans[1]);
   }
-
-  return rv;
 }
 
 void HdmaSetup(uint32 addr6, uint32 addr7, uint8 transfer_unit, uint8 reg6, uint8 reg7, uint8 indirect_bank) {

zelda_rtl.h

@@ -42,7 +42,7 @@ void HdmaSetup(uint32 addr6, uint32 addr7, uint8 transfer_unit, uint8 reg6, uint
 
 void ZeldaInitialize();
 void ZeldaReset(bool preserve_sram);
-bool ZeldaDrawPpuFrame(uint8 *pixel_buffer, size_t pitch, uint32 render_flags);
+void ZeldaDrawPpuFrame(uint8 *pixel_buffer, size_t pitch, uint32 render_flags);
 void ZeldaRunFrameInternal(uint16 input, int run_what);
 bool ZeldaRunFrame(int input_state);
 void LoadSongBank(const uint8 *p);