Method OnRealtimeTick

src/intro_gui.cpp:189–255

	}

	void OnRealtimeTick(uint delta_ms) override
	{
		/* Move the main game viewport according to intro viewport commands. */

		if (intro_viewport_commands.empty()) return;

		bool suppress_panning = true;
		if (this->mouse_idle_pos.x != _cursor.pos.x || this->mouse_idle_pos.y != _cursor.pos.y) {
			this->mouse_idle_pos = _cursor.pos;
			this->mouse_idle_time = 2000;
		} else if (this->mouse_idle_time > delta_ms) {
			this->mouse_idle_time -= delta_ms;
		} else {
			this->mouse_idle_time = 0;
			suppress_panning = false;
		}

		/* Determine whether to move to the next command or stay at current. */
		bool changed_command = false;
		if (this->cur_viewport_command_index >= intro_viewport_commands.size()) {
			/* Reached last, rotate back to start of the list. */
			this->cur_viewport_command_index = 0;
			changed_command = true;
		} else {
			/* Check if current command has elapsed and switch to next. */
			this->cur_viewport_command_time += delta_ms;
			if (this->cur_viewport_command_time >= intro_viewport_commands[this->cur_viewport_command_index].delay) {
				this->cur_viewport_command_index = (this->cur_viewport_command_index + 1) % intro_viewport_commands.size();
				this->cur_viewport_command_time = 0;
				changed_command = true;
			}
		}

		IntroGameViewportCommand &vc = intro_viewport_commands[this->cur_viewport_command_index];
		Window *mw = GetMainWindow();

		/* Early exit if the current command hasn't elapsed and isn't animated. */
		if (!changed_command && !vc.pan_to_next && vc.vehicle == VehicleID::Invalid()) return;

		/* Suppress panning commands, while user interacts with GUIs. */
		if (!changed_command && suppress_panning) return;

		/* Reset the zoom level. */
		if (changed_command) FixTitleGameZoom(vc.zoom_adjust);

		/* Calculate current command position (updates followed vehicle coordinates). */
		Point pos = vc.PositionForViewport(*mw->viewport);

		/* Calculate panning (linear interpolation between current and next command position). */
		if (vc.pan_to_next) {
			size_t next_command_index = (this->cur_viewport_command_index + 1) % intro_viewport_commands.size();
			IntroGameViewportCommand &nvc = intro_viewport_commands[next_command_index];
			Point pos2 = nvc.PositionForViewport(*mw->viewport);
			const double t = this->cur_viewport_command_time / (double)vc.delay;
			pos.x = pos.x + (int)(t * (pos2.x - pos.x));
			pos.y = pos.y + (int)(t * (pos2.y - pos.y));
		}