# HG changeset patch
# User frosch <frosch@openttd.org>
# Date 1315753809 0
# Node ID 8adf9c55b5e54f88bb4c9656d97170670249aa8e
# Parent  7338f18ce5e4706d86162c99120ef907cd25bf86
(svn r22924) -Codechange: Enhance NewGRFSpriteLayout for drawing construction stages in spritelayouts with inconsistent number of sprites per spriteset.

diff --git a/src/newgrf.cpp b/src/newgrf.cpp
--- a/src/newgrf.cpp
+++ b/src/newgrf.cpp
@@ -607,9 +607,11 @@
  * @param use_cur_spritesets  Whether to use currently referenceable action 1 sets.
  * @param feature             GrfSpecFeature to use spritesets from.
  * @param [out] grf_sprite    Read sprite and palette.
+ * @param [out] max_sprite_offset  Optionally returns the number of sprites in the spriteset of the sprite. (0 if no spritset)
+ * @param [out] max_palette_offset Optionally returns the number of sprites in the spriteset of the palette. (0 if no spritset)
  * @return Read TileLayoutFlags.
  */
-static TileLayoutFlags ReadSpriteLayoutSprite(ByteReader *buf, bool read_flags, bool invert_action1_flag, bool use_cur_spritesets, byte feature, PalSpriteID *grf_sprite)
+static TileLayoutFlags ReadSpriteLayoutSprite(ByteReader *buf, bool read_flags, bool invert_action1_flag, bool use_cur_spritesets, int feature, PalSpriteID *grf_sprite, uint16 *max_sprite_offset = NULL, uint16 *max_palette_offset = NULL)
 {
 	grf_sprite->sprite = buf->ReadWord();
 	grf_sprite->pal = buf->ReadWord();
@@ -628,6 +630,7 @@
 			grf_sprite->pal = PAL_NONE;
 		} else {
 			SpriteID sprite = use_cur_spritesets ? _cur.GetSprite(feature, index) : index;
+			if (max_sprite_offset != NULL) *max_sprite_offset = use_cur_spritesets ? _cur.GetNumEnts(feature, index) : UINT16_MAX;
 			SB(grf_sprite->sprite, 0, SPRITE_WIDTH, sprite);
 			SetBit(grf_sprite->sprite, SPRITE_MODIFIER_CUSTOM_SPRITE);
 		}
@@ -645,6 +648,7 @@
 			grf_sprite->pal = PAL_NONE;
 		} else {
 			SpriteID sprite = use_cur_spritesets ? _cur.GetSprite(feature, index) : index;
+			if (max_palette_offset != NULL) *max_palette_offset = use_cur_spritesets ? _cur.GetNumEnts(feature, index) : UINT16_MAX;
 			SB(grf_sprite->pal, 0, SPRITE_WIDTH, sprite);
 			SetBit(grf_sprite->pal, SPRITE_MODIFIER_CUSTOM_SPRITE);
 		}
@@ -726,8 +730,13 @@
 	if (!allow_var10) valid_flags &= ~TLF_VAR10_FLAGS;
 	dts->Allocate(num_building_sprites); // allocate before reading groundsprite flags
 
+	uint16 *max_sprite_offset = AllocaM(uint16, num_building_sprites + 1);
+	uint16 *max_palette_offset = AllocaM(uint16, num_building_sprites + 1);
+	MemSetT(max_sprite_offset, 0, num_building_sprites + 1);
+	MemSetT(max_palette_offset, 0, num_building_sprites + 1);
+
 	/* Groundsprite */
-	TileLayoutFlags flags = ReadSpriteLayoutSprite(buf, has_flags, false, use_cur_spritesets, feature, &dts->ground);
+	TileLayoutFlags flags = ReadSpriteLayoutSprite(buf, has_flags, false, use_cur_spritesets, feature, &dts->ground, max_sprite_offset, max_palette_offset);
 	if (_cur.skip_sprites < 0) return true;
 
 	if (flags & ~(valid_flags & ~TLF_NON_GROUND_FLAGS)) {
@@ -742,7 +751,7 @@
 	for (uint i = 0; i < num_building_sprites; i++) {
 		DrawTileSeqStruct *seq = const_cast<DrawTileSeqStruct*>(&dts->seq[i]);
 
-		flags = ReadSpriteLayoutSprite(buf, has_flags, false, use_cur_spritesets, feature, &seq->image);
+		flags = ReadSpriteLayoutSprite(buf, has_flags, false, use_cur_spritesets, feature, &seq->image, max_sprite_offset + i + 1, max_palette_offset + i + 1);
 		if (_cur.skip_sprites < 0) return true;
 
 		if (flags & ~valid_flags) {
@@ -766,6 +775,42 @@
 		if (_cur.skip_sprites < 0) return true;
 	}
 
+	/* Check if the number of sprites per spriteset is consistent */
+	bool is_consistent = true;
+	dts->consistent_max_offset = 0;
+	for (uint i = 0; i < num_building_sprites + 1; i++) {
+		if (max_sprite_offset[i] > 0) {
+			if (dts->consistent_max_offset == 0) {
+				dts->consistent_max_offset = max_sprite_offset[i];
+			} else if (dts->consistent_max_offset != max_sprite_offset[i]) {
+				is_consistent = false;
+				break;
+			}
+		}
+		if (max_palette_offset[i] > 0) {
+			if (dts->consistent_max_offset == 0) {
+				dts->consistent_max_offset = max_palette_offset[i];
+			} else if (dts->consistent_max_offset != max_palette_offset[i]) {
+				is_consistent = false;
+				break;
+			}
+		}
+	}
+
+	/* When the Action1 sets are unknown, everything should be 0 (no spriteset usage) or UINT16_MAX (some spriteset usage) */
+	assert(use_cur_spritesets || (is_consistent && (dts->consistent_max_offset == 0 || dts->consistent_max_offset == UINT16_MAX)));
+
+	if (!is_consistent || dts->registers != NULL) {
+		dts->consistent_max_offset = 0;
+		if (dts->registers == NULL) dts->AllocateRegisters();
+
+		for (uint i = 0; i < num_building_sprites + 1; i++) {
+			TileLayoutRegisters &regs = const_cast<TileLayoutRegisters&>(dts->registers[i]);
+			regs.max_sprite_offset = max_sprite_offset[i];
+			regs.max_palette_offset = max_palette_offset[i];
+		}
+	}
+
 	return false;
 }
 
@@ -1584,6 +1629,7 @@
 
 				for (uint t = 0; t < statspec->tiles; t++) {
 					NewGRFSpriteLayout *dts = &statspec->renderdata[t];
+					dts->consistent_max_offset = UINT16_MAX; // Spritesets are unknown, so no limit.
 
 					if (buf->HasData(4) && *(uint32*)buf->Data() == 0) {
 						buf->Skip(4);
@@ -4403,13 +4449,6 @@
 					assert(TileLayoutSpriteGroup::CanAllocateItem());
 					TileLayoutSpriteGroup *group = new TileLayoutSpriteGroup();
 					act_group = group;
-					/* num_building_stages should be 1, if we are only using non-custom sprites */
-					if (_cur.HasValidSpriteSets(feature)) {
-						/* This assumes that all spritesets have the same number of sprites. */
-						group->num_building_stages = max(1u, _cur.GetNumEnts(feature, 0));
-					} else {
-						group->num_building_stages = 1;
-					}
 
 					/* On error, bail out immediately. Temporary GRF data was already freed */
 					if (ReadSpriteLayout(buf, num_building_sprites, true, feature, false, type == 0, &group->dts)) return;
diff --git a/src/newgrf_commons.cpp b/src/newgrf_commons.cpp
--- a/src/newgrf_commons.cpp
+++ b/src/newgrf_commons.cpp
@@ -571,10 +571,11 @@
  * @param orig_offset          Offset to apply to non-action-1 sprites.
  * @param newgrf_ground_offset Offset to apply to action-1 ground sprites.
  * @param newgrf_offset        Offset to apply to action-1 non-ground sprites.
+ * @param constr_stage         Construction stage (0-3) to apply to all action-1 sprites.
  * @param separate_ground      Whether the ground sprite shall be resolved by a separate action-1-2-3 chain by default.
  * @return Bitmask of values for variable 10 to resolve action-1-2-3 chains for.
  */
-uint32 NewGRFSpriteLayout::PrepareLayout(uint32 orig_offset, uint32 newgrf_ground_offset, uint32 newgrf_offset, bool separate_ground) const
+uint32 NewGRFSpriteLayout::PrepareLayout(uint32 orig_offset, uint32 newgrf_ground_offset, uint32 newgrf_offset, uint constr_stage, bool separate_ground) const
 {
 	result_seq.Clear();
 	uint32 var10_values = 0;
@@ -611,6 +612,7 @@
 		if (!(flags & TLF_SPRITE)) {
 			if (HasBit(result->image.sprite, SPRITE_MODIFIER_CUSTOM_SPRITE)) {
 				result->image.sprite += ground ? newgrf_ground_offset : newgrf_offset;
+				if (constr_stage > 0 && regs != NULL) result->image.sprite += GetConstructionStageOffset(constr_stage, regs->max_sprite_offset);
 			} else {
 				result->image.sprite += orig_offset;
 			}
@@ -626,6 +628,7 @@
 		if (!(flags & TLF_PALETTE)) {
 			if (HasBit(result->image.pal, SPRITE_MODIFIER_CUSTOM_SPRITE)) {
 				result->image.sprite += ground ? newgrf_ground_offset : newgrf_offset;
+				if (constr_stage > 0 && regs != NULL) result->image.sprite += GetConstructionStageOffset(constr_stage, regs->max_palette_offset);
 			}
 		}
 
@@ -663,7 +666,14 @@
 					result->image.sprite = 0;
 				} else {
 					if (HasBit(result->image.sprite, SPRITE_MODIFIER_CUSTOM_SPRITE)) result->image.sprite += resolved_sprite;
-					if (flags & TLF_SPRITE) result->image.sprite += (int16)GetRegister(regs->sprite); // mask to 16 bits to avoid trouble
+					if (flags & TLF_SPRITE) {
+						int16 offset = (int16)GetRegister(regs->sprite); // mask to 16 bits to avoid trouble
+						if (!HasBit(result->image.sprite, SPRITE_MODIFIER_CUSTOM_SPRITE) || (offset >= 0 && offset < regs->max_sprite_offset)) {
+							result->image.sprite += offset;
+						} else {
+							result->image.sprite = SPR_IMG_QUERY;
+						}
+					}
 
 					if (result->IsParentSprite()) {
 						if (flags & TLF_BB_XY_OFFSET) {
@@ -686,7 +696,15 @@
 			if (var10 == resolved_var10) {
 				/* Apply registers */
 				if (HasBit(result->image.pal, SPRITE_MODIFIER_CUSTOM_SPRITE)) result->image.pal += resolved_sprite;
-				if (flags & TLF_PALETTE) result->image.pal += (int16)GetRegister(regs->palette); // mask to 16 bits to avoid trouble
+				if (flags & TLF_PALETTE) {
+					int16 offset = (int16)GetRegister(regs->palette); // mask to 16 bits to avoid trouble
+					if (!HasBit(result->image.pal, SPRITE_MODIFIER_CUSTOM_SPRITE) || (offset >= 0 && offset < regs->max_palette_offset)) {
+						result->image.pal += offset;
+					} else {
+						result->image.sprite = SPR_IMG_QUERY;
+						result->image.pal = PAL_NONE;
+					}
+				}
 			}
 		}
 
diff --git a/src/newgrf_commons.h b/src/newgrf_commons.h
--- a/src/newgrf_commons.h
+++ b/src/newgrf_commons.h
@@ -96,6 +96,8 @@
 	uint8 dodraw;          ///< Register deciding whether the sprite shall be drawn at all. Non-zero means drawing.
 	uint8 sprite;          ///< Register specifying a signed offset for the sprite.
 	uint8 palette;         ///< Register specifying a signed offset for the palette.
+	uint16 max_sprite_offset;  ///< Maximum offset to add to the sprite. (limited by size of the spriteset)
+	uint16 max_palette_offset; ///< Maximum offset to add to the palette. (limited by size of the spriteset)
 	union {
 		uint8 parent[3];   ///< Registers for signed offsets for the bounding box position of parent sprites.
 		uint8 child[2];    ///< Registers for signed offsets for the position of child sprites.
@@ -114,6 +116,12 @@
 struct NewGRFSpriteLayout : ZeroedMemoryAllocator, DrawTileSprites {
 	const TileLayoutRegisters *registers;
 
+	/**
+	 * Number of sprites in all referenced spritesets.
+	 * If these numbers are inconsistent, then this is 0 and the real values are in \c registers.
+	 */
+	uint consistent_max_offset;
+
 	void Allocate(uint num_sprites);
 	void AllocateRegisters();
 	void Clone(const DrawTileSeqStruct *source);
@@ -147,7 +155,7 @@
 		return this->registers != NULL;
 	}
 
-	uint32 PrepareLayout(uint32 orig_offset, uint32 newgrf_ground_offset, uint32 newgrf_offset, bool separate_ground) const;
+	uint32 PrepareLayout(uint32 orig_offset, uint32 newgrf_ground_offset, uint32 newgrf_offset, uint constr_stage, bool separate_ground) const;
 	void ProcessRegisters(uint8 resolved_var10, uint32 resolved_sprite, bool separate_ground) const;
 
 	/**
diff --git a/src/newgrf_spritegroup.cpp b/src/newgrf_spritegroup.cpp
--- a/src/newgrf_spritegroup.cpp
+++ b/src/newgrf_spritegroup.cpp
@@ -236,12 +236,14 @@
  */
 const DrawTileSprites *TileLayoutSpriteGroup::ProcessRegisters(uint8 *stage) const
 {
-	if (stage != NULL) *stage = GetConstructionStageOffset(*stage, this->num_building_stages);
-	if (!this->dts.NeedsPreprocessing()) return &this->dts;
+	if (!this->dts.NeedsPreprocessing()) {
+		if (stage != NULL && this->dts.consistent_max_offset > 0) *stage = GetConstructionStageOffset(*stage, this->dts.consistent_max_offset);
+		return &this->dts;
+	}
 
 	static DrawTileSprites result;
 	uint8 actual_stage = stage != NULL ? *stage : 0;
-	this->dts.PrepareLayout(0, actual_stage, actual_stage, false);
+	this->dts.PrepareLayout(0, 0, 0, actual_stage, false);
 	this->dts.ProcessRegisters(0, 0, false);
 	result.seq = this->dts.GetLayout(&result.ground);
 
diff --git a/src/newgrf_spritegroup.h b/src/newgrf_spritegroup.h
--- a/src/newgrf_spritegroup.h
+++ b/src/newgrf_spritegroup.h
@@ -288,7 +288,6 @@
 	TileLayoutSpriteGroup() : SpriteGroup(SGT_TILELAYOUT) {}
 	~TileLayoutSpriteGroup() {}
 
-	byte num_building_stages;    ///< Number of building stages to show for this house/industry tile
 	NewGRFSpriteLayout dts;
 
 	const DrawTileSprites *ProcessRegisters(uint8 *stage) const;
diff --git a/src/newgrf_station.cpp b/src/newgrf_station.cpp
--- a/src/newgrf_station.cpp
+++ b/src/newgrf_station.cpp
@@ -838,7 +838,7 @@
 	if (layout != NULL) {
 		/* Sprite layout which needs preprocessing */
 		bool separate_ground = HasBit(statspec->flags, SSF_SEPARATE_GROUND);
-		uint32 var10_values = layout->PrepareLayout(total_offset, rti->fallback_railtype, 0, separate_ground);
+		uint32 var10_values = layout->PrepareLayout(total_offset, rti->fallback_railtype, 0, 0, separate_ground);
 		uint8 var10;
 		FOR_EACH_SET_BIT(var10, var10_values) {
 			uint32 var10_relocation = GetCustomStationRelocation(statspec, NULL, INVALID_TILE, var10);
diff --git a/src/station_cmd.cpp b/src/station_cmd.cpp
--- a/src/station_cmd.cpp
+++ b/src/station_cmd.cpp
@@ -2687,7 +2687,7 @@
 		if (layout != NULL) {
 			/* Sprite layout which needs preprocessing */
 			bool separate_ground = HasBit(statspec->flags, SSF_SEPARATE_GROUND);
-			uint32 var10_values = layout->PrepareLayout(total_offset, rti->fallback_railtype, 0, separate_ground);
+			uint32 var10_values = layout->PrepareLayout(total_offset, rti->fallback_railtype, 0, 0, separate_ground);
 			uint8 var10;
 			FOR_EACH_SET_BIT(var10, var10_values) {
 				uint32 var10_relocation = GetCustomStationRelocation(statspec, st, ti->tile, var10);