[sis] 03/03: Reduce the amount of repaint events when resizing windows.

[desruisseaux]

This is an automated email from the ASF dual-hosted git repository.

desruisseaux pushed a commit to branch geoapi-4.0
in repository https://gitbox.apache.org/repos/asf/sis.git

commit 0daa2b6ab49625fc52c15a286acf88b551ad2d8a
Author: Martin Desruisseaux <martin.desruisse...@geomatys.com>
AuthorDate: Sun Oct 17 21:14:06 2021 +0200

    Reduce the amount of repaint events when resizing windows.
---
 .../main/java/org/apache/sis/gui/map/MapCanvas.java    | 18 ++++++++++++++++++
 .../main/java/org/apache/sis/gui/map/MapCanvasAWT.java | 10 ++++++++++
 2 files changed, 28 insertions(+)

diff --git 
a/application/sis-javafx/src/main/java/org/apache/sis/gui/map/MapCanvas.java 
b/application/sis-javafx/src/main/java/org/apache/sis/gui/map/MapCanvas.java
index 288bfda..f8241bb 100644
--- a/application/sis-javafx/src/main/java/org/apache/sis/gui/map/MapCanvas.java
+++ b/application/sis-javafx/src/main/java/org/apache/sis/gui/map/MapCanvas.java
@@ -358,11 +358,29 @@ public abstract class MapCanvas extends PlanarCanvas {
     }
 
     /**
+     * Returns the bounds of the content in {@link #floatingPane} coordinates, 
or {@code null} if unknown.
+     * Some subclasses may compute a larger image than the widget size for 
better visual transition during
+     * pan or zoom-out. If such margin exists, it may not be necessary to 
repaint the canvas on size change.
+     */
+    Bounds getBoundsInParent() {
+        return null;
+    }
+
+    /**
      * Invoked when the size of the {@linkplain #floatingPane} has changed.
      * This method requests a new repaint after a short wait, in order to 
collect more resize events.
      */
     private void onSizeChanged() {
         sizeChanged = true;
+        final Bounds bp = getBoundsInParent();
+        if (bp != null) {
+            if (bp.getMinX() <= 0 && bp.getMinY() <= 0  &&
+                bp.getMaxX() >= floatingPane.getWidth() &&
+                bp.getMaxY() >= floatingPane.getHeight())
+            {
+                return;
+            }
+        }
         requestRepaint();
     }
 
diff --git 
a/application/sis-javafx/src/main/java/org/apache/sis/gui/map/MapCanvasAWT.java 
b/application/sis-javafx/src/main/java/org/apache/sis/gui/map/MapCanvasAWT.java
index 3fd42b7..863cbcb 100644
--- 
a/application/sis-javafx/src/main/java/org/apache/sis/gui/map/MapCanvasAWT.java
+++ 
b/application/sis-javafx/src/main/java/org/apache/sis/gui/map/MapCanvasAWT.java
@@ -30,6 +30,7 @@ import java.awt.image.RenderedImage;
 import java.awt.image.BufferedImage;
 import java.awt.image.VolatileImage;
 import javafx.application.Platform;
+import javafx.geometry.Bounds;
 import javafx.geometry.Insets;
 import javafx.geometry.Rectangle2D;
 import javafx.scene.image.ImageView;
@@ -154,6 +155,15 @@ public abstract class MapCanvasAWT extends MapCanvas {
     }
 
     /**
+     * Returns the image bounds. This is used for determining if a
+     * repaint is necessary after {@link MapCanvas} size changed.
+     */
+    @Override
+    final Bounds getBoundsInParent() {
+        return image.getBoundsInParent();
+    }
+
+    /**
      * Clears {@link #buffer} and all support fields.
      */
     private void clearBuffer() {