Bug 500013 - [Wayland] Keyboard Left and Right Arrow keys are very slow

or unresponsive 

The Caret drawing mechanism was originally implemented to be done using
a generated cairo from parent window using gdk_cairo_create(). This is
now deprecated and not working in Wayland. Drawing of the caret is now
handled in a draw signal which is triggered by a queue_draw() call.  

Change-Id: I0b6e50140b4e104e13ca2e6cbc1d97c8488e1b2c
Signed-off-by: Ian Pun <ipun@redhat.com>
Signed-off-by: Alexander Kurtakov <akurtako@redhat.com>

2 files changed, 115 insertions, 53 deletions

diff --git a/bundles/org.eclipse.swt/Eclipse SWT/gtk/org/eclipse/swt/widgets/Canvas.java b/bundles/org.eclipse.swt/Eclipse SWT/gtk/org/eclipse/swt/widgets/Canvas.java
index 8843f9148d..242d395b7e 100644
--- a/bundles/org.eclipse.swt/Eclipse SWT/gtk/org/eclipse/swt/widgets/Canvas.java
+++ b/bundles/org.eclipse.swt/Eclipse SWT/gtk/org/eclipse/swt/widgets/Canvas.java
@@ -42,6 +42,7 @@ import org.eclipse.swt.internal.gtk.*;
 public class Canvas extends Composite {
 	Caret caret;
 	IME ime;
+	private boolean drawFlag;
 
 Canvas () {}
 
@@ -167,13 +168,63 @@ long /*int*/ gtk_commit (long /*int*/ imcontext, long /*int*/ text) {
 @Override
 long /*int*/ gtk_draw (long /*int*/ widget, long /*int*/ cairo) {
 	if ((state & OBSCURED) != 0) return 0;
-	boolean isFocus = caret != null && caret.isFocusCaret ();
-	if (isFocus) caret.killFocus ();
-	long /*int*/ result = super.gtk_draw (widget, cairo);
-	if (isFocus) caret.setFocus ();
+	long /*int*/ result;
+	if ( OS.GTK_VERSION < OS.VERSION(3, 22, 0)) {
+		boolean isFocus = caret != null && caret.isFocusCaret ();
+		if (isFocus) caret.killFocus ();
+		 result = super.gtk_draw (widget, cairo);
+		if (isFocus) caret.setFocus ();
+	} else {
+		result = super.gtk_draw (widget, cairo);
+		if (caret != null && caret.isDrawing) {
+			drawCaret(widget,cairo);
+			caret.isDrawing = false;
+		}
+	}
 	return result;
 }
 
+private void drawCaret (long /*int*/ widget, long /*int*/ cairo) {
+	if(this.isDisposed()) return;
+	if (cairo == 0) error(SWT.ERROR_NO_HANDLES);
+	if (!drawFlag) {
+		Cairo.cairo_save(cairo);
+		if (caret.image != null && !caret.image.isDisposed() && caret.image.mask == 0) {
+			Cairo.cairo_set_source_rgb(cairo, 1, 1, 1);
+			Cairo.cairo_set_operator(cairo, Cairo.CAIRO_OPERATOR_DIFFERENCE);
+			long /*int*/ surface = Cairo.cairo_get_target(cairo);
+			int nWidth = 0;
+			switch (Cairo.cairo_surface_get_type(surface)) {
+				case Cairo.CAIRO_SURFACE_TYPE_IMAGE:
+					nWidth = Cairo.cairo_image_surface_get_width(surface);
+					break;
+				case Cairo.CAIRO_SURFACE_TYPE_XLIB:
+					nWidth = Cairo.cairo_xlib_surface_get_width(surface);
+					break;
+			}
+			int nX = caret.x;
+			if ((style & SWT.MIRRORED) != 0) nX = getClientWidth () - nWidth - nX;
+			Cairo.cairo_translate(cairo, nX, caret.y);
+			Cairo.cairo_set_source_surface(cairo, caret.image.surface, 0, 0);
+			Cairo.cairo_paint(cairo);
+		} else {
+			Cairo.cairo_set_source_rgb(cairo, 1, 1, 1);
+			Cairo.cairo_set_operator(cairo, Cairo.CAIRO_OPERATOR_DIFFERENCE);
+			int nWidth = caret.width, nHeight = caret.height;
+			if (nWidth <= 0) nWidth = Caret.DEFAULT_WIDTH;
+			int nX = caret.x;
+			if ((style & SWT.MIRRORED) != 0) nX = getClientWidth () - nWidth - nX;
+			Cairo.cairo_rectangle(cairo, nX, caret.y, nWidth, nHeight);
+			}
+		Cairo.cairo_fill(cairo);
+		Cairo.cairo_restore(cairo);
+		drawFlag = true;
+	} else {
+		drawFlag = false;
+		}
+	return;
+}
+
 @Override
 long /*int*/ gtk_expose_event (long /*int*/ widget, long /*int*/ event) {
 	if ((state & OBSCURED) != 0) return 0;
diff --git a/bundles/org.eclipse.swt/Eclipse SWT/gtk/org/eclipse/swt/widgets/Caret.java b/bundles/org.eclipse.swt/Eclipse SWT/gtk/org/eclipse/swt/widgets/Caret.java
index be0015207c..bceeec6637 100644
--- a/bundles/org.eclipse.swt/Eclipse SWT/gtk/org/eclipse/swt/widgets/Caret.java
+++ b/bundles/org.eclipse.swt/Eclipse SWT/gtk/org/eclipse/swt/widgets/Caret.java
@@ -38,7 +38,7 @@ import org.eclipse.swt.internal.gtk.*;
 public class Caret extends Widget {
 	Canvas parent;
 	int x, y, width, height;
-	boolean isVisible, isShowing;
+	boolean isVisible, isShowing, isDrawing;
 	int blinkRate;
 	Image image;
 	Font font;
@@ -99,64 +99,75 @@ void createWidget (int index) {
 boolean drawCaret () {
 	if (parent == null) return false;
 	if (parent.isDisposed ()) return false;
-	long /*int*/ window = parent.paintWindow ();
-	if (OS.USE_CAIRO) {
-		long /*int*/ cairo = OS.gdk_cairo_create(window);
-		if (cairo == 0) error(SWT.ERROR_NO_HANDLES);
-		Cairo.cairo_set_source_rgb(cairo, 1, 1, 1);
-		Cairo.cairo_set_operator(cairo, Cairo.CAIRO_OPERATOR_DIFFERENCE);
-		if (image != null && !image.isDisposed() && image.mask == 0) {
-			long /*int*/ surface = Cairo.cairo_get_target(cairo);
-			int nWidth = 0;
-			switch (Cairo.cairo_surface_get_type(surface)) {
-				case Cairo.CAIRO_SURFACE_TYPE_IMAGE:
-					nWidth = Cairo.cairo_image_surface_get_width(surface);
-					break;
-				case Cairo.CAIRO_SURFACE_TYPE_XLIB:
-					nWidth = Cairo.cairo_xlib_surface_get_width(surface);
-					break;
+	if (OS.GTK_VERSION < OS.VERSION (3, 22, 0)) {
+		long /*int*/ window = parent.paintWindow ();
+		if (OS.USE_CAIRO) {
+			long /*int*/ cairo = OS.gdk_cairo_create(window);
+			if (cairo == 0) error(SWT.ERROR_NO_HANDLES);
+			Cairo.cairo_set_source_rgb(cairo, 1, 1, 1);
+			Cairo.cairo_set_operator(cairo, Cairo.CAIRO_OPERATOR_DIFFERENCE);
+			if (image != null && !image.isDisposed() && image.mask == 0) {
+				long /*int*/ surface = Cairo.cairo_get_target(cairo);
+				int nWidth = 0;
+				switch (Cairo.cairo_surface_get_type(surface)) {
+					case Cairo.CAIRO_SURFACE_TYPE_IMAGE:
+						nWidth = Cairo.cairo_image_surface_get_width(surface);
+						break;
+					case Cairo.CAIRO_SURFACE_TYPE_XLIB:
+						nWidth = Cairo.cairo_xlib_surface_get_width(surface);
+						break;
+				}
+				int nX = x;
+				if ((parent.style & SWT.MIRRORED) != 0) nX = parent.getClientWidth () - nWidth - nX;
+				Cairo.cairo_translate(cairo, nX, y);
+				Cairo.cairo_set_source_surface(cairo, image.surface, 0, 0);
+				Cairo.cairo_paint(cairo);
+			} else {
+				int nWidth = width, nHeight = height;
+				if (nWidth <= 0) nWidth = DEFAULT_WIDTH;
+				int nX = x;
+				if ((parent.style & SWT.MIRRORED) != 0) nX = parent.getClientWidth () - nWidth - nX;
+				Cairo.cairo_rectangle(cairo, nX, y, nWidth, nHeight);
+
 			}
-			int nX = x;
-			if ((parent.style & SWT.MIRRORED) != 0) nX = parent.getClientWidth () - nWidth - nX;
-			Cairo.cairo_translate(cairo, nX, y);
-			Cairo.cairo_set_source_surface(cairo, image.surface, 0, 0);
-			Cairo.cairo_paint(cairo);
+			Cairo.cairo_fill(cairo);
+			Cairo.cairo_destroy(cairo);
+			return true;
+		}
+		long /*int*/ gc = OS.gdk_gc_new (window);
+		GdkColor color = new GdkColor ();
+		color.red = (short) 0xffff;
+		color.green = (short) 0xffff;
+		color.blue = (short) 0xffff;
+		long /*int*/ colormap = OS.gdk_colormap_get_system ();
+		OS.gdk_colormap_alloc_color (colormap, color, true, true);
+		OS.gdk_gc_set_foreground (gc, color);
+		OS.gdk_gc_set_function (gc, OS.GDK_XOR);
+		if (image != null && !image.isDisposed() && image.mask == 0) {
+			int[] width = new int[1]; int[] height = new int[1];
+			OS.gdk_pixmap_get_size (image.pixmap, width, height);
+		 	int nX = x;
+			if ((parent.style & SWT.MIRRORED) != 0) nX = parent.getClientWidth () - width[0] - nX;
+		 	OS.gdk_draw_drawable(window, gc, image.pixmap, 0, 0, nX, y, width[0], height[0]);
 		} else {
 			int nWidth = width, nHeight = height;
 			if (nWidth <= 0) nWidth = DEFAULT_WIDTH;
 			int nX = x;
 			if ((parent.style & SWT.MIRRORED) != 0) nX = parent.getClientWidth () - nWidth - nX;
-			Cairo.cairo_rectangle(cairo, nX, y, nWidth, nHeight);
+			OS.gdk_draw_rectangle (window, gc, 1, nX, y, nWidth, nHeight);
 		}
-		Cairo.cairo_fill(cairo);
-		Cairo.cairo_destroy(cairo);
+		OS.g_object_unref (gc);
+		OS.gdk_colormap_free_colors (colormap, color, 1);
 		return true;
-	}
-	long /*int*/ gc = OS.gdk_gc_new (window);
-	GdkColor color = new GdkColor ();
-	color.red = (short) 0xffff;
-	color.green = (short) 0xffff;
-	color.blue = (short) 0xffff;
-	long /*int*/ colormap = OS.gdk_colormap_get_system ();
-	OS.gdk_colormap_alloc_color (colormap, color, true, true);
-	OS.gdk_gc_set_foreground (gc, color);
-	OS.gdk_gc_set_function (gc, OS.GDK_XOR);
-	if (image != null && !image.isDisposed() && image.mask == 0) {
-		int[] width = new int[1]; int[] height = new int[1];
-		OS.gdk_pixmap_get_size (image.pixmap, width, height);
-	 	int nX = x;
-		if ((parent.style & SWT.MIRRORED) != 0) nX = parent.getClientWidth () - width[0] - nX;
-	 	OS.gdk_draw_drawable(window, gc, image.pixmap, 0, 0, nX, y, width[0], height[0]);
 	} else {
-		int nWidth = width, nHeight = height;
-		if (nWidth <= 0) nWidth = DEFAULT_WIDTH;
-		int nX = x;
-		if ((parent.style & SWT.MIRRORED) != 0) nX = parent.getClientWidth () - nWidth - nX;
-		OS.gdk_draw_rectangle (window, gc, 1, nX, y, nWidth, nHeight);
+		if (isDrawing) {
+			return false;
+		} else {
+			isDrawing = true;
+			OS.gtk_widget_queue_draw(parent.handle);
+			return true;
+		}
 	}
-	OS.g_object_unref (gc);
-	OS.gdk_colormap_free_colors (colormap, color, 1);
-	return true;
 }
 
 /**