Reindex all level cel blocks

Author: StephenCWills

Source/levels/gendung.cpp

@@ -524,12 +524,11 @@ void SetDungeonMicros()
 		uint16_t *pieces = &levelPieces[blocks * levelPieceId];
 		for (uint32_t block = 0; block < blocks; block++) {
 			const LevelCelBlock levelCelBlock { SDL_SwapLE16(pieces[blocks - 2 + (block & 1) - (block & 0xE)]) };
-			LevelCelBlock &mt = DPieceMicros[levelPieceId].mt[block];
-			mt = levelCelBlock;
+			DPieceMicros[levelPieceId].mt[block] = levelCelBlock;
 			if (levelCelBlock.hasValue()) {
 				if (const auto it = frameToTypeMap.find(levelCelBlock.frame()); it == frameToTypeMap.end()) {
 					frameToTypeMap.emplace_hint(it, levelCelBlock.frame(),
-					    DunFrameInfo { static_cast<uint8_t>(block), levelCelBlock.type(), SOLData[levelPieceId], &mt.data });
+					    DunFrameInfo { static_cast<uint8_t>(block), levelCelBlock.type(), SOLData[levelPieceId] });
 				}
 			}
 		}
@@ -539,7 +538,21 @@ void SetDungeonMicros()
 		return a.first < b.first;
 	});
 	ReencodeDungeonCels(pDungeonCels, frameToTypeList);
-	ReindexCelBlocks(frameToTypeList);
+
+	std::vector<std::pair<uint16_t, uint16_t>> celBlockAdjustments = ComputeCelBlockAdjustments(frameToTypeList);
+	if (celBlockAdjustments.size() == 0) return;
+	for (size_t levelPieceId = 0; levelPieceId < tileCount / blocks; levelPieceId++) {
+		for (uint32_t block = 0; block < blocks; block++) {
+			LevelCelBlock &levelCelBlock = DPieceMicros[levelPieceId].mt[block];
+			const uint16_t frame = levelCelBlock.frame();
+			const auto pair = std::make_pair(frame, frame);
+			const auto it = std::upper_bound(celBlockAdjustments.begin(), celBlockAdjustments.end(), pair,
+			    [](std::pair<uint16_t, uint16_t> p1, std::pair<uint16_t, uint16_t> p2) { return p1.first < p2.first; });
+			if (it != celBlockAdjustments.end()) {
+				levelCelBlock.data -= it->second;
+			}
+		}
+	}
 }
 
 void DRLG_InitTrans()

Source/levels/reencode_dun_cels.cpp

@@ -3,9 +3,11 @@
 #include <cstddef>
 #include <cstdint>
 #include <cstring>
+#include <limits>
 #include <memory>
 #include <span>
 #include <utility>
+#include <vector>
 
 #include <SDL_endian.h>
 
@@ -301,15 +303,21 @@ void ReencodeDungeonCels(std::unique_ptr<std::byte[]> &dungeonCels, std::span<st
 	dungeonCels = std::move(result);
 }
 
-void ReindexCelBlocks(std::span<std::pair<uint16_t, DunFrameInfo>> frames)
+std::vector<std::pair<uint16_t, uint16_t>> ComputeCelBlockAdjustments(std::span<std::pair<uint16_t, DunFrameInfo>> frames)
 {
+	std::vector<std::pair<uint16_t, uint16_t>> celBlockAdjustments;
 	uint16_t lastFrameIndex = 0;
 	uint16_t adjustment = 0;
 	for (auto &[frame, info] : frames) {
-		adjustment += frame - lastFrameIndex - 1;
+		uint16_t diff = frame - lastFrameIndex - 1;
+		if (diff > 0) celBlockAdjustments.emplace_back(frame, adjustment);
+		adjustment += diff;
 		lastFrameIndex = frame;
-		*info.celBlockData -= adjustment;
 	}
+	if (adjustment > 0) {
+		celBlockAdjustments.emplace_back(std::numeric_limits<uint16_t>::max(), adjustment);
+	}
+	return celBlockAdjustments;
 }
 
 } // namespace devilution

Source/levels/reencode_dun_cels.hpp

@@ -5,6 +5,7 @@
 #include <memory>
 #include <span>
 #include <utility>
+#include <vector>
 
 #include "levels/dun_tile.hpp"
 
@@ -17,8 +18,6 @@ struct DunFrameInfo {
 	TileType type;
 	TileProperties properties;
 
-	uint16_t *celBlockData;
-
 	[[nodiscard]] bool isFloor() const
 	{
 		// The BlockMissile check is for stairs in L3 and L4, e.g. tile 46 sub-tile 141 frame 386 in L4.
@@ -39,11 +38,11 @@ struct DunFrameInfo {
 void ReencodeDungeonCels(std::unique_ptr<std::byte[]> &dungeonCels, std::span<std::pair<uint16_t, DunFrameInfo>> frames);
 
 /**
- * @brief Adjusts frame indexes in cel block data.
+ * @brief Computes adjustments to apply to frame indexes in cel block data.
  *
  * Re-encoding the dungeon cels removes frames that are not referenced.
  * Indexes must also be adjusted to avoid errors when doing lookups.
  */
-void ReindexCelBlocks(std::span<std::pair<uint16_t, DunFrameInfo>> frames);
+std::vector<std::pair<uint16_t, uint16_t>> ComputeCelBlockAdjustments(std::span<std::pair<uint16_t, DunFrameInfo>> frames);
 
 } // namespace devilution