(svn r16220) -Fix [FS#2862]: possible crashes when quiting OpenTTD or forcing resizes/redraws of the screen during map generation

src/gfx.cpp

@@ -19,6 +19,7 @@
 #include "landscape_type.h"
 #include "network/network_func.h"
 #include "core/smallvec_type.hpp"
+#include "thread.h"
 
 #include "table/palettes.h"
 #include "table/sprites.h"
@@ -1275,7 +1276,18 @@ void DrawDirtyBlocks()
 	int x;
 	int y;
 
-	if (IsGeneratingWorld() && !IsGeneratingWorldReadyForPaint()) return;
+	if (IsGeneratingWorld()) {
+		/* We are generating the world, so release our rights to the map and
+		 * painting while we are waiting a bit. */
+		_genworld_paint_mutex->EndCritical();
+		_genworld_mapgen_mutex->EndCritical();
+
+		/* Wait a while and update _realtime_tick so we are given the rights */
+		CSleep(GENWORLD_REDRAW_TIMEOUT);
+		_realtime_tick += GENWORLD_REDRAW_TIMEOUT;
+		_genworld_paint_mutex->BeginCritical();
+		_genworld_mapgen_mutex->BeginCritical();
+	}
 
 	y = 0;
 	do {
@@ -1343,12 +1355,6 @@ void DrawDirtyBlocks()
 	_invalid_rect.top = h;
 	_invalid_rect.right = 0;
 	_invalid_rect.bottom = 0;
-
-	/* If we are generating a world, and waiting for a paint run, mark it here
-	 *  as done painting, so we can continue generating. */
-	if (IsGeneratingWorld() && IsGeneratingWorldReadyForPaint()) {
-		SetGeneratingWorldPaintStatus(false);
-	}
 }
 
 /*!