Class HiDPIUtils


  • public class HiDPIUtils
    extends Object
    • Constructor Detail

      • HiDPIUtils

        public HiDPIUtils()
    • Method Detail

      • paintAtScale1x

        public static void paintAtScale1x​(Graphics2D g,
                                          int x,
                                          int y,
                                          int width,
                                          int height,
                                          HiDPIUtils.Painter painter)
        Paint at system scale factor 1x to avoid rounding issues at 125%, 150% and 175% scaling.

        Scales the given Graphics2D down to 100% and invokes the given painter passing scaled x, y, width and height.

        Uses the same scaling calculation as the JRE uses.

      • computeTextYCorrection

        public static float computeTextYCorrection​(Graphics2D g)
        When painting text on HiDPI screens and the JRE scales, then the text is painted too far down on some operating systems. The higher the system scale factor is, the more.

        This method computes a correction value for the Y position.

      • drawStringWithYCorrection

        public static void drawStringWithYCorrection​(JComponent c,
                                                     Graphics2D g,
                                                     String text,
                                                     int x,
                                                     int y)
        Applies Y correction and draws the given string at the specified location. The provided component is used to query text properties and anti-aliasing hints.

        Use this method instead of Graphics.drawString(String, int, int) for correct anti-aliasing.

        Replacement for SwingUtilities2.drawString().

      • drawStringUnderlineCharAtWithYCorrection

        public static void drawStringUnderlineCharAtWithYCorrection​(JComponent c,
                                                                    Graphics2D g,
                                                                    String text,
                                                                    int underlinedIndex,
                                                                    int x,
                                                                    int y)
        Applies Y correction and draws the given string at the specified location underlining the specified character. The provided component is used to query text properties and anti-aliasing hints.

        Replacement for SwingUtilities2.drawStringUnderlineCharAt().

      • createGraphicsTextYCorrection

        public static Graphics2D createGraphicsTextYCorrection​(Graphics2D g)
        Creates a graphics object and applies Y correction to string drawing methods. If no Y correction is necessary, the passed in graphics object is returned.
      • repaint

        public static void repaint​(Component c,
                                   int x,
                                   int y,
                                   int width,
                                   int height)
        Repaints the given component area.

        Invokes Component.repaint(int, int, int, int) on the given component,

        Use this method, instead of Component.repaint(...), to fix a problem in Swing when using scale factors that end on .25 or .75 (e.g. 1.25, 1.75, 2.25, etc) and repainting single components, which may not repaint right and/or bottom 1px edge of component.

        The problem may occur under following conditions:

        • using Java 9 or later
        • system scale factor is 125%, 175%, 225%, ... (Windows only; Java on macOS and Linux does not support fractional scale factors)
        • repaint whole component or right/bottom area of component
        • component is opaque; or component is contained in a opaque container that has same right/bottom bounds as component
        • component has bounds that Java/Swing scales different when repainting components
        Since:
        3.5
      • installHiDPIRepaintManager

        public static void installHiDPIRepaintManager()
        Installs a HiDPIUtils.HiDPIRepaintManager on Windows when running in Java 9+, but only if default repaint manager is currently installed.

        Invoke once on application startup. Compatible with all/other LaFs.

        Since:
        3.5