Index: src/viewport.cpp
===================================================================
--- src/viewport.cpp	(wersja 27117)
+++ src/viewport.cpp	(kopia robocza)
@@ -1509,7 +1509,8 @@
 
 				/* For some strange reason, those fields inside tile_info are uints. However,
 				 * in the old code their copies in an int variable where compared against zero. */
-				if (0 < x && x < (int)MapMaxX() && 0 < y && y < (int)MapMaxY()) {
+				if (IsInsideMM(x, _settings_game.construction.freeform_edges ? 1 : 0, MapMaxX()) &&
+						IsInsideMM(y, _settings_game.construction.freeform_edges ? 1 : 0, MapMaxY())) {
 					/* We are inside the map => paint landscape. */
 					tile_info.tile = TileXY(tile_info.x, tile_info.y);
 					tile_info.tileh = GetTilePixelSlope(tile_info.tile, &tile_info.z);