[win32] Foward native zoom to draw bitmap in GC

This commit adapts the logic when a bitmap or icon is drawn with the GC
in the windows implementation. As of now,  the autoscale zoom was used to
identify the image handle to use. If the image is itself drawn with a
ImageGCDrawer, information about the original native zoom was lost, which
led to inconsistencies in fonts depending on the auto scale mode. This
commit fowards the native zoom in this case to enable the Image to
initialize the GC accordingly.

fixes #2385
fixes #2311

Author: akoch-yatta

bundles/org.eclipse.swt/Eclipse SWT/win32/org/eclipse/swt/graphics/GC.java

@@ -1253,7 +1253,7 @@ private void drawImage(Image srcImage, int srcX, int srcY, int srcWidth, int src
 		}
 		return;
 	}
-	long imageHandle = Image.win32_getHandle(srcImage, imageZoom);
+	long imageHandle = srcImage.getHandle(imageZoom, data.nativeZoom);
 	switch (srcImage.type) {
 		case SWT.BITMAP:
 			drawBitmap(srcImage, imageHandle, srcX, srcY, srcWidth, srcHeight, destX, destY, destWidth, destHeight, simple);
@@ -4384,7 +4384,7 @@ private void init(Drawable drawable, GCData data, long hDC) {
 	}
 	Image image = data.image;
 	if (image != null) {
-		data.hNullBitmap = OS.SelectObject(hDC, Image.win32_getHandle(image, data.nativeZoom));
+		data.hNullBitmap = OS.SelectObject(hDC, image.getHandle(data.imageZoom, data.nativeZoom));
 		image.memGC = this;
 	}
 	int layout = data.layout;

bundles/org.eclipse.swt/Eclipse SWT/win32/org/eclipse/swt/graphics/GCData.java

@@ -48,6 +48,7 @@ public final class GCData {
 	public float lineMiterLimit = 10;
 	public int alpha = 0xFF;
 	public int nativeZoom;
+	int imageZoom;
 
 	public Image image;
 	public PAINTSTRUCT ps;
@@ -67,6 +68,7 @@ void copyTo(GCData originalData) {
 		originalData.font = font;
 		originalData.nativeZoom = nativeZoom;
 		originalData.image = image;
+		originalData.imageZoom = imageZoom;
 		originalData.ps = ps;
 		originalData.layout = layout;
 		originalData.hwnd = hwnd;

bundles/org.eclipse.swt/Eclipse SWT/win32/org/eclipse/swt/graphics/Image.java

@@ -809,10 +809,15 @@ private ImageHandle getImageMetadata(ZoomContext zoomContext) {
  * @noreference This method is not intended to be referenced by clients.
  */
 public static long win32_getHandle (Image image, int zoom) {
-	if (image.isDisposed()) {
+	return image.getHandle(zoom, zoom);
+}
+
+long getHandle (int targetZoom, int nativeZoom) {
+	if (isDisposed()) {
 		return 0L;
 	}
-	return image.getImageMetadata(new ZoomContext(zoom)).handle;
+	ZoomContext zoomContext = imageProvider.getFittingZoomContext(targetZoom, nativeZoom);
+	return getImageMetadata(zoomContext).handle;
 }
 
 /**
@@ -1752,6 +1757,7 @@ private long configureGC(GCData data, ZoomContext zoomContext) {
 		}
 		data.device = device;
 		data.nativeZoom = zoomContext.nativeZoom();
+		data.imageZoom = zoomContext.targetZoom();
 		data.image = this;
 		data.font = SWTFontProvider.getSystemFont(device, zoomContext.nativeZoom());
 	}
@@ -1913,6 +1919,10 @@ private abstract class AbstractImageProviderWrapper {
 
 	protected abstract Rectangle getBounds(int zoom);
 
+	protected ZoomContext getFittingZoomContext(int targetZoom, int nativeZoom) {
+		return new ZoomContext(targetZoom);
+	}
+
 	protected long configureGCData(GCData data) {
 		return configureGC(data, new ZoomContext(100));
 	}
@@ -2138,14 +2148,22 @@ private class PlainImageProviderWrapper extends AbstractImageProviderWrapper {
 		type = SWT.BITMAP;
 	}
 
+	@Override
+	protected ZoomContext getFittingZoomContext(int targetZoom, int nativeZoom) {
+		if (memGC != null) {
+			return new ZoomContext(targetZoom, nativeZoom);
+		}
+		return super.getFittingZoomContext(targetZoom, nativeZoom);
+	}
+
 	@Override
 	public Collection<Integer> getPreservedZoomLevels() {
 		return Collections.singleton(baseZoom);
 	}
 
 	@Override
 	protected long configureGCData(GCData data) {
-		return configureGC(data, new ZoomContext(DPIUtil.getDeviceZoom()));
+		return configureGC(data, new ZoomContext(DPIUtil.getDeviceZoom(), DPIUtil.getNativeDeviceZoom()));
 	}
 
 	@Override
@@ -2577,6 +2595,11 @@ private class ImageGcDrawerWrapper extends DynamicImageProviderWrapper {
 		this.height = height;
 	}
 
+	@Override
+	protected ZoomContext getFittingZoomContext(int targetZoom, int nativeZoom) {
+		return new ZoomContext(targetZoom, nativeZoom);
+	}
+
 	@Override
 	protected Rectangle getBounds(int zoom) {
 		Rectangle rectangle = new Rectangle(0, 0, width, height);