message: Fixed build issue for shadows example
diff: @@ -223,8 +223,9 @@ impl MainState {
  glow: 0.0,
  strength: LIGHT_STRENGTH,
  };
  + let color_format = ggez::graphics::get_window_color_format(ctx);
  let foreground = Canvas::with_window_size(ctx)?;
  - let occlusions = Canvas::new(ctx, LIGHT_RAY_COUNT, 1, conf::NumSamples::One)?;
  + let occlusions = Canvas::new(ctx, LIGHT_RAY_COUNT, 1, conf::NumSamples::One, color_format)?;
  let mut shadows = Canvas::with_window_size(ctx)?;
  // The shadow map will be drawn on top using the multiply blend mode
  shadows.set_blend_mode(Some(BlendMode::Multiply));
  