org.netbeans.api.visual.widget.LevelOfDetailsWidget Maven / Gradle / Ivy
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* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you under the Apache License, Version 2.0 (the
* "License"); you may not use this file except in compliance
* with the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing,
* software distributed under the License is distributed on an
* "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
* KIND, either express or implied. See the License for the
* specific language governing permissions and limitations
* under the License.
*/
package org.netbeans.api.visual.widget;
import java.awt.*;
/**
* This is a widget with a level-of-details feature. The visibility of children is based on the zoom factor of a scene.
*
* For < hardMinimalZoom and > hardMaximalZoom the children are not painted.
* For < softMinimalZoom and > sortMaximalZoom the children are partially painted using alpha-blending.
* Between softMinimalZoom and softMaximalZoom the children are painted normally.
*
* @author David Kaspar
*/
public class LevelOfDetailsWidget extends Widget {
private double hardMinimalZoom;
private double softMinimalZoom;
private double softMaximalZoom;
private double hardMaximalZoom;
/**
* Creates a level-of-details widget.
* @param scene the scene
* @param hardMinimalZoom the hard minimal zoom factor
* @param softMinimalZoom the sort minimal zoom factor
* @param softMaximalZoom the sort maximal zoom factor
* @param hardMaximalZoom the hard maximal zoom factor
*/
public LevelOfDetailsWidget(Scene scene, double hardMinimalZoom, double softMinimalZoom, double softMaximalZoom, double hardMaximalZoom) {
super (scene);
this.hardMinimalZoom = hardMinimalZoom;
this.softMinimalZoom = softMinimalZoom;
this.softMaximalZoom = softMaximalZoom;
this.hardMaximalZoom = hardMaximalZoom;
}
/**
* Paints children based on the zoom factor.
*/
public void paintChildren () {
double zoom = getScene ().getZoomFactor();
if (zoom <= hardMinimalZoom || zoom >= hardMaximalZoom)
return;
Graphics2D gr = getGraphics();
Composite previousComposite = null;
if (hardMinimalZoom < zoom && zoom < softMinimalZoom) {
double diff = softMinimalZoom - hardMinimalZoom;
if (diff > 0.0) {
diff = (zoom - hardMinimalZoom) / diff;
previousComposite = gr.getComposite();
gr.setComposite(AlphaComposite.getInstance (AlphaComposite.SRC_OVER, (float) diff));
}
} else if (softMaximalZoom < zoom && zoom < hardMaximalZoom) {
double diff = hardMaximalZoom - softMaximalZoom;
if (diff > 0.0) {
diff = (hardMaximalZoom - zoom) / diff;
previousComposite = gr.getComposite();
gr.setComposite(AlphaComposite.getInstance (AlphaComposite.SRC_OVER, (float) diff));
}
}
super.paintChildren ();
if (previousComposite != null)
gr.setComposite(previousComposite);
}
/**
* Checks whether a specified local location is a part of a widget based on the zoom factor.
* @param localLocation the local location
* @return true, it it is
*/
public boolean isHitAt(Point localLocation) {
double zoom = getScene().getZoomFactor();
if (zoom < hardMinimalZoom || zoom > hardMaximalZoom)
return false;
return super.isHitAt(localLocation);
}
}