JAL-3609 HiDPI scale setting done via system prop in getdown or halview.bin.Launcher

[jalview.git] / getdown / src / getdown / core / src / main / java / jalview / bin / HiDPISetting.java

diff --git a/getdown/src/getdown/core/src/main/java/jalview/bin/HiDPISetting.java b/getdown/src/getdown/core/src/main/java/jalview/bin/HiDPISetting.java
new file mode 100644 (file)
index 0000000..5e20d76
--- /dev/null
+++ b/getdown/src/getdown/core/src/main/java/jalview/bin/HiDPISetting.java
@@ -0,0 +1,48 @@
+package jalview.bin;
+
+import java.awt.Toolkit;
+
+public class HiDPISetting
+{
+  public static final int dpi;
+
+  public static final int scale;
+
+  private static final int hidpi = 110;
+
+  private static final String scaleProperty = "sun.java2d.uiScale";
+
+  private static final boolean isAMac = System.getProperty("os.name")
+          .indexOf("Mac") > -1;
+
+  private static final boolean isLinux = System.getProperty("os.name")
+          .toLowerCase().indexOf("linux") > -1;
+
+  private static final boolean isWindows = System.getProperty("os.name")
+          .toLowerCase().indexOf("windows") > -1;
+
+  static
+  {
+    dpi = Toolkit.getDefaultToolkit().getScreenResolution();
+    scale = dpi / hidpi + 1;
+    if (scale > 1 && isLinux)
+    {
+      System.out.println("DPI detected as " + dpi
+              + ". Scaling factor set to " + scale + ".");
+    }
+  }
+
+  public static String getScalePropertyArg()
+  {
+    // HiDPI setting. Just looking at Linux to start with. Test with Windows.
+    if (!isLinux)
+    {
+      return null;
+    }
+    if (scale > 1)
+    {
+      return "-D" + scaleProperty + "=" + scale;
+    }
+    return null;
+  }
+}