Bug 529431: [GTK3.10+] Snippet294 fails to draw Region

Allow GtkWindow (usually Shells) to be shaped using
gdk_window_shape_combine_region() instead of cairo_clip. GtkWindow
is unaffected by the changes in GTK3.10 so this is fine.

A snippet has been added to test this functionality, and to test for the
case mentioned in comment 8 of bug 529431.

Change-Id: I40c80599e015553576fc8979181577c1170146d2
Signed-off-by: Eric Williams <ericwill@redhat.com>

6 files changed, 101 insertions, 5 deletions

diff --git a/bundles/org.eclipse.swt/Eclipse SWT PI/gtk/library/os.c b/bundles/org.eclipse.swt/Eclipse SWT PI/gtk/library/os.c
index 5fc92d0de9..565ee2ac1c 100644
--- a/bundles/org.eclipse.swt/Eclipse SWT PI/gtk/library/os.c
+++ b/bundles/org.eclipse.swt/Eclipse SWT PI/gtk/library/os.c
@@ -4228,6 +4228,18 @@ JNIEXPORT jintLong JNICALL GTK_NATIVE(_1GTK_1TYPE_1WIDGET)
 }
 #endif
 
+#ifndef NO__1GTK_1TYPE_1WINDOW
+JNIEXPORT jintLong JNICALL GTK_NATIVE(_1GTK_1TYPE_1WINDOW)
+	(JNIEnv *env, jclass that)
+{
+	jintLong rc = 0;
+	GTK_NATIVE_ENTER(env, that, _1GTK_1TYPE_1WINDOW_FUNC);
+	rc = (jintLong)GTK_TYPE_WINDOW;
+	GTK_NATIVE_EXIT(env, that, _1GTK_1TYPE_1WINDOW_FUNC);
+	return rc;
+}
+#endif
+
 #ifndef NO__1GTK_1WIDGET_1SET_1FLAGS
 JNIEXPORT void JNICALL GTK_NATIVE(_1GTK_1WIDGET_1SET_1FLAGS)
 	(JNIEnv *env, jclass that, jintLong arg0, jint arg1)
diff --git a/bundles/org.eclipse.swt/Eclipse SWT PI/gtk/library/os_stats.c b/bundles/org.eclipse.swt/Eclipse SWT PI/gtk/library/os_stats.c
index 98f36e68bb..01f966424d 100644
--- a/bundles/org.eclipse.swt/Eclipse SWT PI/gtk/library/os_stats.c
+++ b/bundles/org.eclipse.swt/Eclipse SWT PI/gtk/library/os_stats.c
@@ -321,6 +321,7 @@ char * GTK_nativeFunctionNames[] = {
 	"_1GTK_1TYPE_1IM_1MULTICONTEXT",
 	"_1GTK_1TYPE_1MENU",
 	"_1GTK_1TYPE_1WIDGET",
+	"_1GTK_1TYPE_1WINDOW",
 	"_1GTK_1WIDGET_1SET_1FLAGS",
 	"_1GTK_1WIDGET_1UNSET_1FLAGS",
 	"_1gtk_1accel_1group_1new",
diff --git a/bundles/org.eclipse.swt/Eclipse SWT PI/gtk/library/os_stats.h b/bundles/org.eclipse.swt/Eclipse SWT PI/gtk/library/os_stats.h
index 97f4d144ee..64a3069337 100644
--- a/bundles/org.eclipse.swt/Eclipse SWT PI/gtk/library/os_stats.h
+++ b/bundles/org.eclipse.swt/Eclipse SWT PI/gtk/library/os_stats.h
@@ -319,6 +319,7 @@ typedef enum {
 	_1GTK_1TYPE_1IM_1MULTICONTEXT_FUNC,
 	_1GTK_1TYPE_1MENU_FUNC,
 	_1GTK_1TYPE_1WIDGET_FUNC,
+	_1GTK_1TYPE_1WINDOW_FUNC,
 	_1GTK_1WIDGET_1SET_1FLAGS_FUNC,
 	_1GTK_1WIDGET_1UNSET_1FLAGS_FUNC,
 	_1gtk_1accel_1group_1new_FUNC,
diff --git a/bundles/org.eclipse.swt/Eclipse SWT PI/gtk/org/eclipse/swt/internal/gtk/GTK.java b/bundles/org.eclipse.swt/Eclipse SWT PI/gtk/org/eclipse/swt/internal/gtk/GTK.java
index ae31f7be36..ff3427fa12 100644
--- a/bundles/org.eclipse.swt/Eclipse SWT PI/gtk/org/eclipse/swt/internal/gtk/GTK.java
+++ b/bundles/org.eclipse.swt/Eclipse SWT PI/gtk/org/eclipse/swt/internal/gtk/GTK.java
@@ -478,6 +478,16 @@ public class GTK extends OS {
 			lock.unlock();
 		}
 	}
+	/** @method flags=const */
+	public static final native long /*int*/ _GTK_TYPE_WINDOW();
+	public static final long /*int*/ GTK_TYPE_WINDOW() {
+		lock.lock();
+		try {
+			return _GTK_TYPE_WINDOW();
+		} finally {
+			lock.unlock();
+		}
+	}
 	public static final native void _GTK_WIDGET_SET_FLAGS(long /*int*/ wid, int flag);
 	public static final void GTK_WIDGET_SET_FLAGS(long /*int*/ wid, int flag) {
 		lock.lock();
diff --git a/bundles/org.eclipse.swt/Eclipse SWT/gtk/org/eclipse/swt/widgets/Control.java b/bundles/org.eclipse.swt/Eclipse SWT/gtk/org/eclipse/swt/widgets/Control.java
index 7df9fe52fb..b16a51a9b7 100644
--- a/bundles/org.eclipse.swt/Eclipse SWT/gtk/org/eclipse/swt/widgets/Control.java
+++ b/bundles/org.eclipse.swt/Eclipse SWT/gtk/org/eclipse/swt/widgets/Control.java
@@ -64,7 +64,7 @@ public abstract class Control extends Widget implements Drawable {
 	Accessible accessible;
 	Control labelRelation;
 	String cssBackground, cssForeground = " ";
-	boolean reparentOnVisibility;
+	boolean drawRegion;
 
 	LinkedList <Event> dragDetectionQueue;
 
@@ -1343,11 +1343,16 @@ public void setRegion (Region region) {
 	if (region != null && region.isDisposed()) error (SWT.ERROR_INVALID_ARGUMENT);
 	long /*int*/ shape_region = (region == null) ? 0 : region.handle;
 	this.region = region;
-	// Only call gdk_window_shape_combine_region on GTK3.8-
-	if (GTK.GTK_VERSION < OS.VERSION(3, 9, 0)) {
-		long /*int*/ window = gtk_widget_get_window (topHandle ());
+	long /*int*/ topHandle = topHandle ();
+	/*
+	 * Only call gdk_window_shape_combine_region on GTK3.10-, or if the widget is
+	 * a GtkWindow.
+	 */
+	if (GTK.GTK_VERSION < OS.VERSION(3, 10, 0) || OS.G_OBJECT_TYPE(topHandle) == GTK.GTK_TYPE_WINDOW()) {
+		long /*int*/ window = gtk_widget_get_window (topHandle);
 		GDK.gdk_window_shape_combine_region (window, shape_region, 0, 0);
 	} else {
+		drawRegion = (this.region != null && this.region.handle != 0);
 		GTK.gtk_widget_queue_draw(topHandle());
 	}
 }
@@ -3536,7 +3541,7 @@ long /*int*/ gtk_draw (long /*int*/ widget, long /*int*/ cairo) {
 	 * Doesn't modify input handling at this time.
 	 * See bug 529431.
 	 */
-	if (this.region != null && this.region.handle != 0 && GTK.GTK_VERSION >= OS.VERSION(3, 10, 0)) {
+	if (drawRegion) {
 		long /*int*/ regionHandle = this.region.handle;
 		GdkRectangle regionRect = new GdkRectangle();
 		/*
diff --git a/tests/org.eclipse.swt.tests.gtk/ManualTests/org/eclipse/swt/tests/gtk/snippets/Bug529431_ShellSetRegion.java b/tests/org.eclipse.swt.tests.gtk/ManualTests/org/eclipse/swt/tests/gtk/snippets/Bug529431_ShellSetRegion.java
new file mode 100644
index 0000000000..65b0f428eb
--- /dev/null
+++ b/tests/org.eclipse.swt.tests.gtk/ManualTests/org/eclipse/swt/tests/gtk/snippets/Bug529431_ShellSetRegion.java
@@ -0,0 +1,67 @@
+/*******************************************************************************
+ * Copyright (c) 2018 Red Hat and others.
+ * All rights reserved. This program and the accompanying materials
+ * are made available under the terms of the Eclipse Public License v1.0
+ * which accompanies this distribution, and is available at
+ * http://www.eclipse.org/legal/epl-v10.html
+ *
+ * Contributors:
+ *     Red Hat - initial API and implementation
+ *******************************************************************************/
+package org.eclipse.swt.tests.gtk.snippets;
+
+import org.eclipse.swt.SWT;
+import org.eclipse.swt.graphics.Region;
+import org.eclipse.swt.widgets.Display;
+import org.eclipse.swt.widgets.Shell;
+
+/*
+ * Title: Bug 529431: [GTK3.10+] Snippet294 fails to draw Region
+ * How to run: launch snippet and look for the resulting Shell
+ * Bug description: the Shell is a 200 x 200 square with no region set
+ * Expected results: the Shell is circle with inner circular regions
+ * GTK Version(s): GTK3.10+
+ */
+public class Bug529431_ShellSetRegion {
+
+	static int[] circle(int r, int offsetX, int offsetY) {
+		int[] polygon = new int[8 * r + 4];
+		// x^2 + y^2 = r^2
+		for (int i = 0; i < 2 * r + 1; i++) {
+			int x = i - r;
+			int y = (int)Math.sqrt(r*r - x*x);
+			polygon[2*i] = offsetX + x;
+			polygon[2*i+1] = offsetY + y;
+			polygon[8*r - 2*i - 2] = offsetX + x;
+			polygon[8*r - 2*i - 1] = offsetY - y;
+		}
+		return polygon;
+	}
+
+	public static void main(String[] args) {
+		final Display display = new Display();
+
+		final Shell shell = new Shell(display, SWT.NO_TRIM | SWT.ON_TOP
+				| SWT.NO_FOCUS | SWT.TOOL);
+
+		shell.setSize(200,200);
+
+		// define a region that looks like a circle with two holes in it
+		Region region = new Region();
+		region.add(circle(67, 87, 77));
+		region.subtract(circle(20, 87, 47));
+		region.subtract(circle(20, 87, 113));
+
+		// define the shape of the shell using setRegion
+		shell.setRegion(region);
+		shell.open();
+
+		while (!shell.isDisposed()) {
+			if (!display.readAndDispatch())
+				display.sleep();
+		}
+		region.dispose();
+		display.dispose();
+	}
+
+}