First draft for Program Scaling Improvement

Author: amartya4256

bundles/org.eclipse.swt/Eclipse SWT PI/win32/library/com.c

@@ -1,5 +1,5 @@
 /*******************************************************************************
- * Copyright (c) 2000, 2022 IBM Corporation and others.
+ * Copyright (c) 2000, 2025 IBM Corporation and others.
  *
  * This program and the accompanying materials
  * are made available under the terms of the Eclipse Public License 2.0
@@ -870,6 +870,24 @@ JNIEXPORT jlong JNICALL COM_NATIVE(SHCreateMemStream)
 }
 #endif
 
+#ifndef NO_SHGetImageList
+JNIEXPORT jlong JNICALL COM_NATIVE(SHGetImageList)
+	(JNIEnv *env, jclass that, jint arg0, jobject arg1, jlongArray arg2)
+{
+	GUID _arg1, *lparg1=NULL;
+	jlong *lparg2=NULL;
+	jlong rc = 0;
+	COM_NATIVE_ENTER(env, that, SHGetImageList_FUNC);
+	if (arg1) if ((lparg1 = getGUIDFields(env, arg1, &_arg1)) == NULL) goto fail;
+		if (arg2) if ((lparg2 = (*env)->GetPrimitiveArrayCritical(env, arg2, NULL)) == NULL) goto fail;
+	rc = (jlong)SHGetImageList(arg0, lparg1, (VOID **)lparg2);
+fail:
+		if (arg2 && lparg2) (*env)->ReleasePrimitiveArrayCritical(env, arg2, lparg2, 0);
+	COM_NATIVE_EXIT(env, that, SHGetImageList_FUNC);
+	return rc;
+}
+#endif
+
 #ifndef NO_STGMEDIUM_1sizeof
 JNIEXPORT jint JNICALL COM_NATIVE(STGMEDIUM_1sizeof)
 	(JNIEnv *env, jclass that)

bundles/org.eclipse.swt/Eclipse SWT PI/win32/library/com_stats.h

@@ -1,5 +1,5 @@
 /*******************************************************************************
- * Copyright (c) 2000, 2023 IBM Corporation and others.
+ * Copyright (c) 2000, 2025 IBM Corporation and others.
  *
  * This program and the accompanying materials
  * are made available under the terms of the Eclipse Public License 2.0
@@ -83,6 +83,7 @@ typedef enum {
 	RevokeDragDrop_FUNC,
 	SHCreateItemFromParsingName_FUNC,
 	SHCreateMemStream_FUNC,
+	SHGetImageList_FUNC,
 	STGMEDIUM_1sizeof_FUNC,
 	StgCreateDocfile_FUNC,
 	StgIsStorageFile_FUNC,

bundles/org.eclipse.swt/Eclipse SWT PI/win32/library/os.c

@@ -3981,6 +3981,18 @@ JNIEXPORT void JNICALL OS_NATIVE(ImageList_1EndDrag)
 }
 #endif
 
+#ifndef NO_ImageList_1GetIcon
+JNIEXPORT jlong JNICALL OS_NATIVE(ImageList_1GetIcon)
+	(JNIEnv *env, jclass that, jlong arg0, jint arg1, jint arg2)
+{
+	jlong rc = 0;
+	OS_NATIVE_ENTER(env, that, ImageList_1GetIcon_FUNC);
+	rc = (jlong)ImageList_GetIcon((HIMAGELIST)arg0, arg1, (UINT)arg2);
+	OS_NATIVE_EXIT(env, that, ImageList_1GetIcon_FUNC);
+	return rc;
+}
+#endif
+
 #ifndef NO_ImageList_1GetIconSize
 JNIEXPORT jboolean JNICALL OS_NATIVE(ImageList_1GetIconSize)
 	(JNIEnv *env, jclass that, jlong arg0, jintArray arg1, jintArray arg2)

bundles/org.eclipse.swt/Eclipse SWT PI/win32/library/os_stats.h

@@ -310,6 +310,7 @@ typedef enum {
 	ImageList_1DragMove_FUNC,
 	ImageList_1DragShowNolock_FUNC,
 	ImageList_1EndDrag_FUNC,
+	ImageList_1GetIcon_FUNC,
 	ImageList_1GetIconSize_FUNC,
 	ImageList_1GetImageCount_FUNC,
 	ImageList_1Remove_FUNC,

bundles/org.eclipse.swt/Eclipse SWT PI/win32/library/os_structs.c

@@ -1,5 +1,5 @@
 /*******************************************************************************
- * Copyright (c) 2000, 2022 IBM Corporation and others.
+ * Copyright (c) 2000, 2025 IBM Corporation and others.
  *
  * This program and the accompanying materials
  * are made available under the terms of the Eclipse Public License 2.0

bundles/org.eclipse.swt/Eclipse SWT PI/win32/library/os_structs.h

@@ -1,5 +1,5 @@
 /*******************************************************************************
- * Copyright (c) 2000, 2021 IBM Corporation and others.
+ * Copyright (c) 2000, 2025 IBM Corporation and others.
  *
  * This program and the accompanying materials
  * are made available under the terms of the Eclipse Public License 2.0

bundles/org.eclipse.swt/Eclipse SWT PI/win32/org/eclipse/swt/internal/ole/win32/COM.java

@@ -107,7 +107,7 @@ public class COM extends OS {
 	public static final GUID IIDIAccessibleImage = IIDFromString("{FE5ABB3D-615E-4f7b-909F-5F0EDA9E8DDE}"); //$NON-NLS-1$
 	public static final GUID IIDIAccessibleApplication = IIDFromString("{D49DED83-5B25-43F4-9B95-93B44595979E}"); //$NON-NLS-1$
 	public static final GUID IIDIAccessibleContext = IIDFromString("{77A123E4-5794-44e0-B8BF-DE600C9D29BD}"); //$NON-NLS-1$
-
+	public static final GUID IID_IImageList = IIDFromString("{46EB5926-582E-4017-9FDF-E8998DAA0950}");
 	/** Constants */
 	public static final int CF_TEXT = 1;
 	public static final int CF_BITMAP = 2;
@@ -465,6 +465,11 @@ private static GUID IIDFromString(String lpsz) {
  * @param ppv cast=(void **)
  */
 public static final native int SHCreateItemFromParsingName (char [] pszName, long pbc, GUID riid, long [] ppv);
+/**
+ * @param riid flags=no_out
+ * @param ppvObj cast=(VOID **),flags=no_in critical
+ */
+public static final native long SHGetImageList (int iImageList, GUID riid, long[] ppvObj);
 /**
  * @param pwcsName cast=(const WCHAR *),flags=no_out
  * @param ppstgOpen cast=(IStorage **)

bundles/org.eclipse.swt/Eclipse SWT PI/win32/org/eclipse/swt/internal/win32/OS.java

@@ -661,6 +661,7 @@ public class OS extends C {
 	public static final int ILC_COLOR8 = 0x8;
 	public static final int ILC_MASK = 0x1;
 	public static final int ILC_MIRROR = 0x2000;
+	public static final int ILD_TRANSPARENT = 0x00000001;
 	public static final int IMAGE_ICON = 0x1;
 	public static final int IME_CMODE_FULLSHAPE = 0x8;
 	public static final int IME_CMODE_KATAKANA = 0x2;
@@ -1209,9 +1210,14 @@ public class OS extends C {
 	public static final int SET_FEATURE_ON_PROCESS = 0x2;
 	public static final int SHADEBLENDCAPS = 120;
 	public static final int SHGFI_ICON = 0x000000100;
+	public static final int SHGFI_ICONLOCATION = 0x000001000;
 	public static final int SHGFI_SMALLICON= 0x1;
 	public static final int SHGFI_LARGEICON= 0x0;
 	public static final int SHGFI_USEFILEATTRIBUTES = 0x000000010;
+	public static final int SHIL_LARGE = 0x0;
+	public static final int SHIL_SMALL = 0x1;
+	public static final int SHIL_EXTRALARGE = 0x2;
+	public static final int SHIL_SYSSMALL = 0x3;
 	public static final int SIGDN_FILESYSPATH = 0x80058000;
 	public static final int SIF_ALL = 0x17;
 	public static final int SIF_DISABLENOSCROLL = 0x8;
@@ -4458,6 +4464,11 @@ public static int HRESULT_FROM_WIN32(int x) {
 public static final native boolean ShowScrollBar (long hWnd, int wBar, boolean bShow);
 /** @param hWnd cast=(HWND) */
 public static final native boolean ShowWindow (long hWnd, int nCmdShow);
+/**
+ * @param himl cast=(HIMAGELIST)
+ * @param flags cast=(UINT)
+ */
+public static final native long ImageList_GetIcon (long himl, int i, int flags);
 /**
  * @param hdc cast=(HDC)
  * @param lpdi flags=no_out

bundles/org.eclipse.swt/Eclipse SWT Program/win32/org/eclipse/swt/program/Program.java

@@ -20,7 +20,9 @@
 import org.eclipse.swt.*;
 import org.eclipse.swt.graphics.*;
 import org.eclipse.swt.internal.*;
+import org.eclipse.swt.internal.ole.win32.*;
 import org.eclipse.swt.internal.win32.*;
+import org.eclipse.swt.widgets.*;
 
 /**
  * Instances of this class represent programs and
@@ -381,26 +383,20 @@ public ImageData getImageData () {
 public ImageData getImageData (int zoom) {
 	// OS.SHGetFileInfo is System DPI-aware, hence it retrieves the icon with zoom
 	// of primary monitor at the application startup
-	int initialNativeZoom = getPrimaryMonitorZoomAtStartup();
 	if (extension != null) {
 		SHFILEINFO shfi = new SHFILEINFO ();
-		int flags = OS.SHGFI_ICON | OS.SHGFI_USEFILEATTRIBUTES;
-		boolean useLargeIcon = 100 * zoom /  initialNativeZoom >= 200;
-		if(useLargeIcon) {
-			flags |= OS.SHGFI_LARGEICON;
-			initialNativeZoom *= 2;
-		} else {
-			flags |= OS.SHGFI_SMALLICON;
-		}
+		int flags = OS.SHGFI_USEFILEATTRIBUTES | OS.SHGFI_ICONLOCATION;
 		TCHAR pszPath = new TCHAR (0, extension, true);
 		OS.SHGetFileInfo (pszPath.chars, OS.FILE_ATTRIBUTE_NORMAL, shfi, SHFILEINFO.sizeof, flags);
-		if (shfi.hIcon != 0) {
-			Image image = Image.win32_new (null, SWT.ICON, shfi.hIcon, initialNativeZoom);
-			ImageData imageData = image.getImageData (zoom);
-			image.dispose ();
+		if (shfi.iIcon >= 0) {
+			Image icon = getImageForZoom(zoom, shfi.iIcon);
+			ImageData imageData = icon.getImageData(zoom);
+			icon.dispose();
 			return imageData;
 		}
 	}
+
+	int initialNativeZoom = getPrimaryMonitorZoomAtStartup();
 	int nIconIndex = 0;
 	String fileName = iconName;
 	int index = iconName.indexOf (',');
@@ -434,6 +430,60 @@ private int getPrimaryMonitorZoomAtStartup() {
 	return DPIUtil.mapDPIToZoom(dpi);
 }
 
+private NavigableMap<Integer, Long> getImageListinAllAvailableSizesMappedWithZoom() {
+	TreeMap<Integer, Long> zoomToHImageList = new TreeMap<>();
+	int primaryMonitorZoomAtStartup = getPrimaryMonitorZoomAtStartup();
+	// SHIL_SYSSMALL is the size of icon at startup zoom of the primary monitor. The
+	// sizes can differ as specified by OS.GetSystemMetrics.
+	long hImageListAtPrimaryMonitorZoomAtStartup = getImageListForSize(OS.SHIL_SYSSMALL);
+	int sizeAtPrimaryMonitorZoomAtStartup = getIconSizeOfImageList(hImageListAtPrimaryMonitorZoomAtStartup);
+	zoomToHImageList.put(primaryMonitorZoomAtStartup, hImageListAtPrimaryMonitorZoomAtStartup);
+	// SHIL_* (SMALL, LARGE and EXTRALARGE) are typically 1x, 2x, 3x relative to the
+	// primary monitor zoom at startup, e.g., 16px, 32px and 48px
+	// respectively.
+	int[] allSizes = new int[] { OS.SHIL_SMALL, OS.SHIL_LARGE, OS.SHIL_EXTRALARGE };
+	for (int size : allSizes) {
+		long hImageList = getImageListForSize(size);
+		int iconSize = getIconSizeOfImageList(hImageList);
+		int zoom = (iconSize / sizeAtPrimaryMonitorZoomAtStartup) * primaryMonitorZoomAtStartup;
+		if (!zoomToHImageList.containsKey(zoom)) {
+			zoomToHImageList.put(zoom, hImageList);
+		} else {
+			OS.ImageList_Destroy(hImageList);
+		}
+	}
+	return zoomToHImageList;
+}
+
+private int getIconSizeOfImageList(long hImageList) {
+	int [] cx = new int [1];
+	int [] cy = new int [1];
+	OS.ImageList_GetIconSize(hImageList, cx, cy);
+	return cx[0];
+}
+
+private Image getImageForZoom(int zoom, int index) {
+	NavigableMap<Integer, Long> zoomToHImageList = getImageListinAllAvailableSizesMappedWithZoom();
+	int closestZoomAvailable = getClosestKey(zoomToHImageList, zoom);
+	long hIcon = OS.ImageList_GetIcon(zoomToHImageList.get(closestZoomAvailable), index, OS.ILD_TRANSPARENT);
+	zoomToHImageList.values().forEach(handle -> OS.ImageList_Destroy(handle));
+	return Image.win32_new(Display.getCurrent(), SWT.ICON, hIcon, closestZoomAvailable);
+}
+
+private long getImageListForSize(int size) {
+	long [] ppv = new long [1];
+	COM.SHGetImageList(size, COM.IID_IImageList, ppv);
+	return ppv[0];
+}
+
+private Integer getClosestKey(NavigableMap<Integer, Long> map, int x) {
+    Integer floorKey = map.floorKey(x);
+    Integer ceilingKey = map.ceilingKey(x);
+    if (floorKey == null) return ceilingKey;
+    if (ceilingKey == null) return floorKey;
+    return (Math.abs(x - floorKey) <= Math.abs(x - ceilingKey)) ? floorKey : ceilingKey;
+}
+
 /**
  * Returns the receiver's name.  This is as short and
  * descriptive a name as possible for the program.  If