Feature: Press ctrl to build diagonal rivers in Scenario Editor (#8880)

1 files changed, 17 insertions, 5 deletions

diff --git a/src/water_cmd.cpp b/src/water_cmd.cpp
index 6a3b73065..731954c2e 100644
--- a/src/water_cmd.cpp
+++ b/src/water_cmd.cpp
@@ -437,7 +437,9 @@ bool RiverModifyDesertZone(TileIndex tile, void *)
  * @param tile end tile of stretch-dragging
  * @param flags type of operation
  * @param p1 start tile of stretch-dragging
- * @param p2 waterclass to build. sea and river can only be built in scenario editor
+ * @param p2 various bitstuffed data
+ *  bits  0-1: waterclass to build. sea and river can only be built in scenario editor
+ *  bit     2: Whether to use the Orthogonal (0) or Diagonal (1) iterator.
  * @param text unused
  * @return the cost of this operation or an error
  */
@@ -449,13 +451,23 @@ CommandCost CmdBuildCanal(TileIndex tile, DoCommandFlag flags, uint32 p1, uint32
 	/* Outside of the editor you can only build canals, not oceans */
 	if (wc != WATER_CLASS_CANAL && _game_mode != GM_EDITOR) return CMD_ERROR;
 
-	TileArea ta(tile, p1);
-
 	/* Outside the editor you can only drag canals, and not areas */
-	if (_game_mode != GM_EDITOR && ta.w != 1 && ta.h != 1) return CMD_ERROR;
+	if (_game_mode != GM_EDITOR) {
+		TileArea ta(tile, p1);
+		if (ta.w != 1 && ta.h != 1) return CMD_ERROR;
+	}
 
 	CommandCost cost(EXPENSES_CONSTRUCTION);
-	TILE_AREA_LOOP(tile, ta) {
+
+	std::unique_ptr<TileIterator> iter;
+	if (HasBit(p2, 2)) {
+		iter = std::make_unique<DiagonalTileIterator>(tile, p1);
+	} else {
+		iter = std::make_unique<OrthogonalTileIterator>(tile, p1);
+	}
+
+	for (; *iter != INVALID_TILE; ++(*iter)) {
+		TileIndex tile = *iter;
 		CommandCost ret;
 
 		Slope slope = GetTileSlope(tile);