Add a configurable scale factor (#230)

* Add swing-dpi dependency

* Implement scale factor

* Improve custom scale dialog, fix crash

* Remove use of $ in identifiers

* Use custom functional interface for scale listeners

* Bump version

Co-authored-by: modmuss50 <modmuss50@gmail.com>

2 files changed, 112 insertions, 0 deletions

diff --git a/src/main/java/cuchaz/enigma/gui/util/ScaleChangeListener.java b/src/main/java/cuchaz/enigma/gui/util/ScaleChangeListener.java
new file mode 100644
index 0000000..d045c6d
--- /dev/null
+++ b/src/main/java/cuchaz/enigma/gui/util/ScaleChangeListener.java
@@ -0,0 +1,8 @@
+package cuchaz.enigma.gui.util;
+
+@FunctionalInterface
+public interface ScaleChangeListener {
+
+        void onScaleChanged(float scale, float oldScale);
+
+}
diff --git a/src/main/java/cuchaz/enigma/gui/util/ScaleUtil.java b/src/main/java/cuchaz/enigma/gui/util/ScaleUtil.java
new file mode 100644
index 0000000..8bc826f
--- /dev/null
+++ b/src/main/java/cuchaz/enigma/gui/util/ScaleUtil.java
@@ -0,0 +1,104 @@
+package cuchaz.enigma.gui.util;
+
+import java.awt.Dimension;
+import java.awt.Font;
+import java.io.IOException;
+import java.lang.reflect.Field;
+import java.util.ArrayList;
+import java.util.List;
+
+import javax.swing.UIManager;
+
+import com.github.swingdpi.UiDefaultsScaler;
+import com.github.swingdpi.plaf.BasicTweaker;
+import com.github.swingdpi.plaf.MetalTweaker;
+import com.github.swingdpi.plaf.NimbusTweaker;
+import com.github.swingdpi.plaf.WindowsTweaker;
+import cuchaz.enigma.config.Config;
+import de.sciss.syntaxpane.DefaultSyntaxKit;
+
+public class ScaleUtil {
+
+        private static List<ScaleChangeListener> listeners = new ArrayList<>();
+
+        public static float getScaleFactor() {
+                return Config.getInstance().scaleFactor;
+        }
+
+        public static void setScaleFactor(float scaleFactor) {
+                float oldScale = getScaleFactor();
+                float clamped = Math.min(Math.max(0.25f, scaleFactor), 10.0f);
+                Config.getInstance().scaleFactor = clamped;
+                try {
+                        Config.getInstance().saveConfig();
+                } catch (IOException e) {
+                        e.printStackTrace();
+                }
+                listeners.forEach(l -> l.onScaleChanged(clamped, oldScale));
+        }
+
+        public static void addListener(ScaleChangeListener listener) {
+                listeners.add(listener);
+        }
+
+        public static void removeListener(ScaleChangeListener listener) {
+                listeners.remove(listener);
+        }
+
+        public static Dimension getDimension(int width, int height) {
+                return new Dimension(scale(width), scale(height));
+        }
+
+        public static Font getFont(String fontName, int plain, int fontSize) {
+                return scaleFont(new Font(fontName, plain, fontSize));
+        }
+
+        public static Font scaleFont(Font font) {
+                return createTweakerForCurrentLook(getScaleFactor()).modifyFont("", font);
+        }
+
+        public static float scale(float f) {
+                return f * getScaleFactor();
+        }
+
+        public static float invert(float f) {
+                return f / getScaleFactor();
+        }
+
+        public static int scale(int i) {
+                return (int) (i * getScaleFactor());
+        }
+
+        public static int invert(int i) {
+                return (int) (i / getScaleFactor());
+        }
+
+        public static void applyScaling() {
+                float scale = getScaleFactor();
+                UiDefaultsScaler.updateAndApplyGlobalScaling((int) (100 * scale), true);
+                try {
+                        Field defaultFontField = DefaultSyntaxKit.class.getDeclaredField("DEFAULT_FONT");
+                        defaultFontField.setAccessible(true);
+                        Font font = (Font) defaultFontField.get(null);
+                        font = font.deriveFont(12 * scale);
+                        defaultFontField.set(null, font);
+                } catch (NoSuchFieldException | IllegalAccessException e) {
+                        e.printStackTrace();
+                }
+        }
+
+        private static BasicTweaker createTweakerForCurrentLook(float dpiScaling) {
+                String testString = UIManager.getLookAndFeel().getName().toLowerCase();
+                if (testString.contains("windows")) {
+                        return new WindowsTweaker(dpiScaling, testString.contains("classic"));
+                }
+                if (testString.contains("metal")) {
+                        return new MetalTweaker(dpiScaling);
+                }
+                if (testString.contains("nimbus")) {
+                        return new NimbusTweaker(dpiScaling);
+                }
+                return new BasicTweaker(dpiScaling);
+        }
+
+}