Method Scroll

src/console_gui.cpp:180–192

* Scroll the content of the console. * @param amount Number of lines to scroll back. */

	 * @param amount Number of lines to scroll back.
	 */
	void Scroll(int amount)
	{
		if (amount < 0) {
			size_t namount = static_cast<size_t>(-amount);
			IConsoleWindow::scroll = (namount > IConsoleWindow::scroll) ? 0 : IConsoleWindow::scroll - namount;
		} else {
			assert(this->height >= 0 && this->line_height > 0);
			size_t visible_lines = static_cast<size_t>(this->height / this->line_height);
			size_t max_scroll = (visible_lines > _iconsole_buffer.size()) ? 0 : _iconsole_buffer.size() + 1 - visible_lines;
			IConsoleWindow::scroll = std::min<size_t>(IConsoleWindow::scroll + amount, max_scroll);
		}
		this->SetDirty();
	}

	void OnPaint() override
	{