Method OnMouseEvent

src/visual_tool.cpp:160–269

template<class FeatureType>
void VisualTool<FeatureType>::OnMouseEvent(wxMouseEvent &event) {
	bool left_click = event.LeftDown();
	bool left_double = event.LeftDClick();
	shift_down = event.ShiftDown();
	ctrl_down = event.CmdDown();
	alt_down = event.AltDown();

	mouse_pos = event.GetPosition();

	if (event.Leaving()) {
		mouse_pos = Vector2D();
		parent->Render();
		return;
	}

	if (!dragging) {
		int max_layer = INT_MIN;
		active_feature = nullptr;
		for (auto& feature : features) {
			if (feature.IsMouseOver(mouse_pos) && feature.layer >= max_layer) {
				active_feature = &feature;
				max_layer = feature.layer;
			}
		}
	}

	if (dragging) {
		// continue drag
		if (event.LeftIsDown()) {
			for (auto sel : sel_features)
				sel->UpdateDrag(mouse_pos - drag_start, shift_down);
			for (auto sel : sel_features)
				UpdateDrag(sel);
			Commit();
		}
		// end drag
		else {
			dragging = false;

			// mouse didn't move, fiddle with selection
			if (active_feature && !active_feature->HasMoved()) {
				// Don't deselect stuff that was selected in this click's mousedown event
				if (!sel_changed) {
					if (ctrl_down)
						RemoveSelection(active_feature);
					else
						SetSelection(active_feature, true);
				}
			}

			active_feature = nullptr;
			parent->ReleaseMouse();
			parent->SetFocus();
		}
	}
	else if (holding) {
		if (!event.LeftIsDown()) {
			holding = false;