Import remove all trees in scenario editor patch.

http://www.tt-forums.net/viewtopic.php?f=33&t=49326

Update to current current version.
Use CMD_LANDSCAPE_CLEAR instead of CMD_CLEAR_AREA.
Whitespace, misc fixes.

src/lang/english.txt

@@ -2819,6 +2819,8 @@ STR_TREES_RANDOM_TYPE                                           :{BLACK}Trees of
 STR_TREES_RANDOM_TYPE_TOOLTIP                                   :{BLACK}Place trees of random type. Shift toggles building/showing cost estimate
 STR_TREES_RANDOM_TREES_BUTTON                                   :{BLACK}Random Trees
 STR_TREES_RANDOM_TREES_TOOLTIP                                  :{BLACK}Plant trees randomly throughout the landscape
+STR_TREES_REMOVE_TREES_BUTTON                                   :{BLACK}Remove all Trees
+STR_TREES_REMOVE_TREES_TOOLTIP                                  :{BLACK}Remove all Trees over landscape
 
 # Land generation window (SE)
 STR_TERRAFORM_TOOLBAR_LAND_GENERATION_CAPTION                   :{WHITE}Land Generation

src/tree_cmd.cpp

@@ -356,6 +356,24 @@ void PlaceTreesRandomly()
 	}
 }
 
+/**
+ * Remove all trees
+ *
+ * This function remove all trees on the map.
+ */
+void RemoveAllTrees()
+{
+	for(uint i = 0; i < MapSizeX(); i++) {
+		for(uint j = 0; j < MapSizeY(); j++) {
+			TileIndex tile = TileXY(i, j);
+			if(GetTileType(tile) == MP_TREES) {
+				DoCommandP(tile, 0, 0, CMD_LANDSCAPE_CLEAR | CMD_MSG(STR_ERROR_CAN_T_CLEAR_THIS_AREA), CcPlaySound10);
+			}
+		}
+	}
+}
+
+
 /**
  * Place new trees.
  *

src/tree_gui.cpp

@@ -28,6 +28,7 @@
 #include "safeguards.h"
 
 void PlaceTreesRandomly();
+void RemoveAllTrees();
 
 /**
  * The build trees window.
@@ -120,6 +121,13 @@ public:
 				PlaceTreesRandomly();
 				MarkWholeScreenDirty();
 				break;
+
+			case WID_BT_REMOVE_ALL: // remove all trees over the landscape
+				if (_settings_client.sound.confirm) SndPlayFx(SND_15_BEEP);
+				RemoveAllTrees();
+				MarkWholeScreenDirty();
+				break;
+
 		}
 	}
 
@@ -213,6 +221,8 @@ static const NWidgetPart _nested_build_trees_widgets[] = {
 				NWidget(WWT_TEXTBTN, COLOUR_GREY, WID_BT_TYPE_RANDOM), SetMinimalSize(139, 12), SetDataTip(STR_TREES_RANDOM_TYPE, STR_TREES_RANDOM_TYPE_TOOLTIP),
 				NWidget(NWID_SPACER), SetMinimalSize(0, 1),
 				NWidget(WWT_PUSHTXTBTN, COLOUR_GREY, WID_BT_MANY_RANDOM), SetMinimalSize(139, 12), SetDataTip(STR_TREES_RANDOM_TREES_BUTTON, STR_TREES_RANDOM_TREES_TOOLTIP),
+				NWidget(NWID_SPACER), SetMinimalSize(0, 1),
+				NWidget(WWT_PUSHTXTBTN, COLOUR_GREY, WID_BT_REMOVE_ALL), SetMinimalSize(139, 12), SetDataTip(STR_TREES_REMOVE_TREES_BUTTON, STR_TREES_REMOVE_TREES_TOOLTIP),
 				NWidget(NWID_SPACER), SetMinimalSize(0, 2),
 			EndContainer(),
 			NWidget(NWID_SPACER), SetMinimalSize(2, 0),

src/widgets/tree_widget.h

@@ -28,6 +28,7 @@ enum BuildTreesWidgets {
 	WID_BT_TYPE_34,         ///< Tree 3st column 4th row.
 	WID_BT_TYPE_RANDOM,     ///< Button to build random type of tree.
 	WID_BT_MANY_RANDOM,     ///< Button to build many random trees.
+	WID_BT_REMOVE_ALL,      ///< Button to remove all trees.
 };
 
 #endif /* WIDGETS_TREE_WIDGET_H */