(svn r18802) -Codechange: Deduplicate drawing-code for depots and stations/waypoints.

src/rail_cmd.cpp

@@ -1944,8 +1944,6 @@ static void DrawTile_Track(TileInfo *ti)
 	} else {
 		/* draw depot */
 		const DrawTileSprites *dts;
-		const DrawTileSeqStruct *dtss;
-		uint32 relocation;
 		SpriteID pal = PAL_NONE;
 
 		if (ti->tileh != SLOPE_FLAT) DrawFoundation(ti, FOUNDATION_LEVELED);
@@ -1957,8 +1955,6 @@ static void DrawTile_Track(TileInfo *ti)
 			dts = &_depot_gfx_table[GetRailDepotDirection(ti->tile)];
 		}
 
-		relocation = rti->total_offset;
-
 		image = dts->ground.sprite;
 		if (image != SPR_FLAT_GRASS_TILE) image += rti->total_offset;
 
@@ -1985,37 +1981,8 @@ static void DrawTile_Track(TileInfo *ti)
 
 		if (HasCatenaryDrawn(GetRailType(ti->tile))) DrawCatenary(ti);
 
-		foreach_draw_tile_seq(dtss, dts->seq) {
-			SpriteID image = dtss->image.sprite;
-			SpriteID pal   = dtss->image.pal;
-
-			/* Stop drawing sprite sequence once we meet a sprite that doesn't have to be opaque */
-			if (IsInvisibilitySet(TO_BUILDINGS) && !HasBit(image, SPRITE_MODIFIER_OPAQUE)) return;
-
-			/* Unlike stations, our default waypoint has no variation for
-			 * different railtype, so don't use the railtype offset if
-			 * no relocation is set */
-			if (HasBit(image, SPRITE_MODIFIER_USE_OFFSET)) {
-				image += rti->total_offset;
-			} else {
-				image += relocation;
-			}
-
-			pal = SpriteLayoutPaletteTransform(image, pal, _drawtile_track_palette);
-
-			if ((byte)dtss->delta_z != 0x80) {
-				AddSortableSpriteToDraw(
-					image, pal,
-					ti->x + dtss->delta_x, ti->y + dtss->delta_y,
-					dtss->size_x, dtss->size_y,
-					dtss->size_z, ti->z + dtss->delta_z,
-					!HasBit(image, SPRITE_MODIFIER_OPAQUE) && IsTransparencySet(TO_BUILDINGS)
-				);
-			} else {
-				/* For stations and original spritelayouts delta_x and delta_y are signed */
-				AddChildSpriteScreen(image, pal, dtss->delta_x, dtss->delta_y, !HasBit(image, SPRITE_MODIFIER_OPAQUE) && IsTransparencySet(TO_BUILDINGS));
-			}
-		}
+		/* No NewGRF depots, so no relocation */
+		DrawStationTileSeq(ti, dts, TO_BUILDINGS, rti->total_offset, 0, _drawtile_track_palette);
 	}
 	DrawBridgeMiddle(ti);
 }

src/station_cmd.cpp

@@ -2457,12 +2457,26 @@ static void DrawTile_Station(TileInfo *ti)
 		total_offset = 0;
 	}
 
-	const DrawTileSeqStruct *dtss;
-	foreach_draw_tile_seq(dtss, t->seq) {
+	DrawStationTileSeq(ti, t, TO_BUILDINGS, total_offset, relocation, palette);
+}
+
+/**
+ * Draws a station, waypoint or depot including all subsprites on a tile.
+ * @param ti The tile to draw on
+ * @param dts Sprite and subsprites to draw
+ * @param to The transparancy bit that toggles drawing of these sprites
+ * @param total_offset Sprite-Offset between the current railtype and normal rail
+ * @param relocation Sprite-Offset for NewGRF defined stations
+ * @param default_palette The default recolour sprite to use (typically company colour)
+ */
+void DrawStationTileSeq(const TileInfo *ti, const DrawTileSprites *dts, TransparencyOption to, int32 total_offset, uint32 relocation, SpriteID default_palette)
+{
+ 	const DrawTileSeqStruct *dtss;
+	foreach_draw_tile_seq(dtss, dts->seq) {
 		SpriteID image = dtss->image.sprite;
 
 		/* Stop drawing sprite sequence once we meet a sprite that doesn't have to be opaque */
-		if (IsInvisibilitySet(TO_BUILDINGS) && !HasBit(image, SPRITE_MODIFIER_OPAQUE)) return;
+		if (IsInvisibilitySet(to) && !HasBit(image, SPRITE_MODIFIER_OPAQUE)) return;
 
 		if (relocation == 0 || HasBit(image, SPRITE_MODIFIER_USE_OFFSET)) {
 			image += total_offset;
@@ -2470,7 +2484,7 @@ static void DrawTile_Station(TileInfo *ti)
 			image += relocation;
 		}
 
-		SpriteID pal = SpriteLayoutPaletteTransform(image, dtss->image.pal, palette);
+		SpriteID pal = SpriteLayoutPaletteTransform(image, dtss->image.pal, default_palette);
 
 		if ((byte)dtss->delta_z != 0x80) {
 			AddSortableSpriteToDraw(
@@ -2478,11 +2492,11 @@ static void DrawTile_Station(TileInfo *ti)
 				ti->x + dtss->delta_x, ti->y + dtss->delta_y,
 				dtss->size_x, dtss->size_y,
 				dtss->size_z, ti->z + dtss->delta_z,
-				!HasBit(image, SPRITE_MODIFIER_OPAQUE) && IsTransparencySet(TO_BUILDINGS)
+				!HasBit(image, SPRITE_MODIFIER_OPAQUE) && IsTransparencySet(to)
 			);
 		} else {
 			/* For stations and original spritelayouts delta_x and delta_y are signed */
-			AddChildSpriteScreen(image, pal, dtss->delta_x, dtss->delta_y, !HasBit(image, SPRITE_MODIFIER_OPAQUE) && IsTransparencySet(TO_BUILDINGS));
+			AddChildSpriteScreen(image, pal, dtss->delta_x, dtss->delta_y, !HasBit(image, SPRITE_MODIFIER_OPAQUE) && IsTransparencySet(to));
 		}
 	}
 }

src/station_func.h

@@ -19,6 +19,7 @@
 #include "tile_type.h"
 #include "cargo_type.h"
 #include "vehicle_type.h"
+#include "transparency.h"
 
 void ModifyStationRatingAround(TileIndex tile, Owner owner, int amount, uint radius);
 
@@ -35,6 +36,8 @@ void UpdateStationAcceptance(Station *st, bool show_msg);
 const DrawTileSprites *GetStationTileLayout(StationType st, byte gfx);
 void StationPickerDrawSprite(int x, int y, StationType st, RailType railtype, RoadType roadtype, int image);
 
+void DrawStationTileSeq(const struct TileInfo *ti, const DrawTileSprites *dts, TransparencyOption to, int32 total_offset, uint32 relocation, SpriteID default_palette);
+
 bool HasStationInUse(StationID station, CompanyID company);
 
 RoadStop *GetRoadStopByTile(TileIndex tile, RoadStopType type);

src/transparency.h

@@ -14,6 +14,7 @@
 
 #include "gfx_func.h"
 #include "openttd.h"
+#include "core/bitmath_func.hpp"
 
 /**
  * Transparency option bits: which position in _transparency_opt stands for which transparency.