fixed tile map editor plugin, all previews are now the same size, closes #4983

scene/gui/item_list.cpp

@@ -729,7 +729,7 @@ static Rect2 _adjust_to_max_size(Size2 p_size, Size2 p_max_size) {
 
 	if (tex_width>size.width) {
 		tex_width=size.width;
-		tex_height=p_size.height * tex_width / p_size.height;
+		tex_height=p_size.height * tex_width / p_size.width;
 	}
 
 	int ofs_x=(size.width - tex_width)/2;

tools/editor/plugins/tile_map_editor_plugin.cpp

@@ -208,9 +208,14 @@ void TileMapEditor::_update_palette() {
 
 	palette->set_max_columns(0);
 	palette->add_constant_override("hseparation", 6);
+
+	float min_size = EDITOR_DEF("tile_map/preview_size",64);
+	palette->set_fixed_icon_size(Size2(min_size, min_size));
+	palette->set_fixed_column_width(min_size*3/2);
 	palette->set_icon_mode(ItemList::ICON_MODE_TOP);
 	palette->set_max_text_lines(2);
 
+
 	String filter = search_box->get_text().strip_edges();
 
 	for (List<int>::Element *E=tiles.front();E;E=E->next()) {
@@ -1434,6 +1439,7 @@ void TileMapEditorPlugin::make_visible(bool p_visible) {
 
 TileMapEditorPlugin::TileMapEditorPlugin(EditorNode *p_node) {
 
+	EDITOR_DEF("tile_map/preview_size",64);
 	tile_map_editor = memnew( TileMapEditor(p_node) );
 	add_control_to_container(CONTAINER_CANVAS_EDITOR_SIDE, tile_map_editor);
 	tile_map_editor->hide();