Function DrawTrainImage

src/train_gui.cpp:98–177

* Draws an image of a whole train * @param v Front vehicle * @param r Rect to draw at * @param selection Selected vehicle to draw a frame around * @param skip Number of pixels to skip at the front (for scrolling) * @param drag_dest The vehicle another one is dragged over, \c VehicleID::Invalid() if none. */

 * @param drag_dest The vehicle another one is dragged over, \c VehicleID::Invalid() if none.
 */
void DrawTrainImage(const Train *v, const Rect &r, VehicleID selection, EngineImageType image_type, int skip, VehicleID drag_dest)
{
	bool rtl = _current_text_dir == TD_RTL;
	Direction dir = rtl ? DIR_E : DIR_W;

	DrawPixelInfo tmp_dpi;
	/* Position of highlight box */
	int highlight_l = 0;
	int highlight_r = 0;
	int max_width = r.Width();

	if (!FillDrawPixelInfo(&tmp_dpi, r)) return;

	{
		AutoRestoreBackup dpi_backup(_cur_dpi, &tmp_dpi);

		bool do_overlays = ShowCargoIconOverlay();
		/* List of overlays, only used if cargo icon overlays are enabled. */
		static std::vector<CargoIconOverlay> overlays;

		int px = rtl ? max_width + skip : -skip;
		int y = r.Height() / 2;
		bool sel_articulated = false;
		bool dragging = (drag_dest != VehicleID::Invalid());
		bool drag_at_end_of_train = (drag_dest == v->index); // Head index is used to mark dragging at end of train.
		for (; v != nullptr && (rtl ? px > 0 : px < max_width); v = v->Next()) {
			if (dragging && !drag_at_end_of_train && drag_dest == v->index) {
				/* Highlight the drag-and-drop destination inside the train. */
				int drag_hlight_width = HighlightDragPosition(px, max_width, y, selection, _cursor.vehchain);
				px += rtl ? -drag_hlight_width : drag_hlight_width;
			}

			Point offset;
			int width = Train::From(v)->GetDisplayImageWidth(&offset);

			if (rtl ? px + width > 0 : px - width < max_width) {
				PaletteID pal = v->vehstatus.Test(VehState::Crashed) ? PALETTE_CRASH : GetVehiclePalette(v);
				VehicleSpriteSeq seq;
				v->GetImage(dir, image_type, &seq);
				seq.Draw(px + (rtl ? -offset.x : offset.x), y + offset.y, pal, v->vehstatus.Test(VehState::Crashed));
			}

			if (!v->IsArticulatedPart()) sel_articulated = false;

			if (v->index == selection) {
				/* Set the highlight position */
				highlight_l = rtl ? px - width : px;
				highlight_r = rtl ? px - 1 : px + width - 1;
				sel_articulated = true;
			} else if ((_cursor.vehchain && highlight_r != 0) || sel_articulated) {
				if (rtl) {
					highlight_l -= width;
				} else {
					highlight_r += width;
				}
			}

			if (do_overlays) AddCargoIconOverlay(overlays, px, width, v);