Function DrawStringMultiLine

src/gfx.cpp:785–829

* Draw string, possibly over multiple lines. * * @param left The left most position to draw on. * @param right The right most position to draw on. * @param top The top most position to draw on. * @param bottom The bottom most position to draw on. * @param str String to draw. * @param colour Colour used for drawing the string, for details see _string_colourmap in * ta

 * @return If \a align is #SA_BOTTOM, the top to where we have written, else the bottom to where we have written.
 */
int DrawStringMultiLine(int left, int right, int top, int bottom, std::string_view str, TextColour colour, StringAlignment align, bool underline, FontSize fontsize)
{
	int maxw = right - left + 1;
	int maxh = bottom - top + 1;

	/* It makes no sense to even try if it can't be drawn anyway, or
	 * do we really want to support fonts of 0 or less pixels high? */
	if (maxh <= 0) return top;

	Layouter layout(str, maxw, fontsize);
	int total_height = layout.GetBounds().height;
	int y;
	switch (align & SA_VERT_MASK) {
		case SA_TOP:
			y = top;
			break;

		case SA_VERT_CENTER:
			y = RoundDivSU(bottom + top - total_height, 2);
			break;

		case SA_BOTTOM:
			y = bottom - total_height;
			break;

		default: NOT_REACHED();
	}

	int last_line = top;
	int first_line = bottom;

	for (const auto &line : layout) {

		int line_height = line->GetLeading();
		if (y >= top && y + line_height - 1 <= bottom) {
			last_line = y + line_height;
			if (first_line > y) first_line = y;

			DrawLayoutLine(*line, y, left, right, align, underline, false, colour);
		}
		y += line_height;
	}

	return ((align & SA_VERT_MASK) == SA_BOTTOM) ? first_line : last_line;
}

/**
 * Draw string, possibly over multiple lines.