java - WorldWind Java 中的闪烁注释

Question

我正在尝试在 NASA Worldwind for Java 中实现我自己的杂波过滤器，它导致了一个奇怪的问题 - 杂波过滤器还没有做太多事情，但当我通过时，我将使用它来移动东西。 “闪烁”问题。每当鼠标移动时，GlobeAnnotation 可渲染对象就会闪烁。当我将杂波过滤器设置为空时，似乎不会发生闪烁。

这是一个 GIF，它显示了我的意思:https://media.giphy.com/media/xT9IgFiZwYZ3VJHQU8/giphy.gif

我从这里克隆了 NASA worldwind 代码:https://github.com/NASAWorldWind/WorldWindJava 。我做了一些更改以使事情适合我的最终过滤器。需要注意的是，我希望 GlobeAnnotations 显示为始终位于其他所有内容之上。

如何使 GlobeAnnotations 不会相互冲突和闪烁，但仍然显示在其他所有内容之上 - 同时打开杂波过滤器？

请注意，以下代码只是我整理的一个示例，用于显示我在“真实”应用程序中看到的问题。我希望 GlobeAnnotations 始终位于其他所有内容之上，但不会闪烁或相互冲突。

这是我的测试驱动程序:

package gov.nasa.worldwindx.examples;

import java.awt.Color;

import gov.nasa.worldwind.geom.LatLon;
import gov.nasa.worldwind.geom.Position;
import gov.nasa.worldwind.layers.AnnotationLayer;
import gov.nasa.worldwind.layers.RenderableLayer;
import gov.nasa.worldwind.render.GlobeAnnotation;
import gov.nasa.worldwind.render.Material;
import gov.nasa.worldwind.render.airspaces.CappedCylinder;

public class FlashyAnnotations extends ApplicationTemplate {
    @SuppressWarnings("unchecked")
    private static class AppFrame extends ApplicationTemplate.AppFrame {

        private AnnotationLayer layer;

        public AppFrame() {

            this.getWwd().getSceneController().setClutterFilter(new SimpleClutterFilter());

            CappedCylinder cappedCyl = new CappedCylinder(LatLon.fromDegrees(27, -100), 3000000);
            cappedCyl.getAttributes().setDrawInterior(true);
            cappedCyl.getAttributes().setInteriorMaterial(Material.GREEN);
            cappedCyl.getAttributes().setInteriorOpacity(.75f);
            cappedCyl.setAltitudes(10, 100000);
            RenderableLayer renderLayer = new RenderableLayer();

            renderLayer.addRenderable(cappedCyl);
            insertBeforeCompass(this.getWwd(), renderLayer);

            // Create example annotations
            this.setupAnnotations();

        }

        private void setupAnnotations() {

            // Create an AnnotationLayer with lots of annotations
            this.layer = new AnnotationLayer();

            GlobeAnnotation ga = new GlobeAnnotation("Annotation", Position.fromDegrees(20, -100.9, 1000));
            ga.getAttributes().setTextColor(Color.white);
            ga.getAttributes().setBackgroundColor(Color.BLACK);
            ga.getAttributes().setOpacity(.75f);
            ga.setAlwaysOnTop(true);
            layer.addAnnotation(ga);

            ga = new GlobeAnnotation("Annotation", Position.fromDegrees(25, -100.9, 1000));
            ga.getAttributes().setTextColor(Color.white);
            ga.getAttributes().setBackgroundColor(Color.BLACK);
            ga.getAttributes().setOpacity(.75f);
            ga.setAlwaysOnTop(true);
            layer.addAnnotation(ga);

            // Add layer to the layer list and update the layer panel
            insertBeforeCompass(this.getWwd(), layer);
        }

    }

    public static void main(String[] args) {
        ApplicationTemplate.start("WorldWind Annotations", AppFrame.class);
    }
}

这是我的(基本上无操作)杂波过滤器:

package gov.nasa.worldwindx.examples;

import java.util.List;

import gov.nasa.worldwind.render.Declutterable;
import gov.nasa.worldwind.render.DrawContext;
import gov.nasa.worldwind.util.ClutterFilter;

public class SimpleClutterFilter implements ClutterFilter{

    @Override
    public void apply(DrawContext dc, List<Declutterable> shapes) {
        for(Declutterable shape: shapes) {
            dc.addOrderedRenderable(shape);
        }

    }

}

我还必须更新 gov.nasa.worldwind.render.BasicAnnotationRenderer 以使其创建的 OrderedAnnotations 实现 Declutterable。 (此内部类的唯一更改是添加 isEnableDecluttering 和 getBounds):

public class OrderedAnnotation implements OrderedRenderable, Declutterable
{
protected Annotation annotation;


protected double eyeDistance;
protected Layer layer;

public OrderedAnnotation(Annotation annotation, double eyeDistance)
{
    this.annotation = annotation;
    this.eyeDistance = eyeDistance;
}

public OrderedAnnotation(Annotation annotation, Layer layer, double eyeDistance)
{
    this.annotation = annotation;
    this.eyeDistance = eyeDistance;
    this.layer = layer;
}

public double getDistanceFromEye()
{
    return this.eyeDistance;
}

public void render(DrawContext dc)
{
    OGLStackHandler stackHandler = new OGLStackHandler();
    BasicAnnotationRenderer.this.beginDrawAnnotations(dc, stackHandler);
    try
    {
        this.doRender(dc, this);
        // Draw as many as we can in a batch to save ogl state switching.
        while (dc.peekOrderedRenderables() instanceof OrderedAnnotation)
        {
            OrderedAnnotation oa = (OrderedAnnotation) dc.pollOrderedRenderables();
            this.doRender(dc, oa);
        }
    }
    catch (WWRuntimeException e)
    {
        Logging.logger().log(Level.SEVERE, "generic.ExceptionWhileRenderingAnnotation", e);
    }
    catch (Exception e)
    {
        Logging.logger().log(Level.SEVERE, "generic.ExceptionWhileRenderingAnnotation", e);
    }
    finally
    {
        BasicAnnotationRenderer.this.endDrawAnnotations(dc, stackHandler);
    }
}

public void pick(DrawContext dc, java.awt.Point pickPoint)
{
    OGLStackHandler stackHandler = new OGLStackHandler();
    BasicAnnotationRenderer.this.pickSupport.clearPickList();
    BasicAnnotationRenderer.this.beginDrawAnnotations(dc, stackHandler);
    try
    {
        this.annotation.setPickSupport(BasicAnnotationRenderer.this.pickSupport);
        this.doRender(dc, this);
        // Draw as many as we can in a batch to save ogl state switching.
        while (dc.peekOrderedRenderables() instanceof OrderedAnnotation)
        {
            OrderedAnnotation oa = (OrderedAnnotation) dc.pollOrderedRenderables();
            oa.annotation.setPickSupport(BasicAnnotationRenderer.this.pickSupport);
            this.doRender(dc, oa);
        }
    }
    catch (WWRuntimeException e)
    {
        Logging.logger().log(Level.SEVERE, "generic.ExceptionWhilePickingAnnotation", e);
    }
    catch (Exception e)
    {
        Logging.logger().log(Level.SEVERE, "generic.ExceptionWhilePickingAnnotation", e);
    }
    finally
    {
        BasicAnnotationRenderer.this.endDrawAnnotations(dc, stackHandler);
        BasicAnnotationRenderer.this.pickSupport.resolvePick(dc, pickPoint, this.layer);
        BasicAnnotationRenderer.this.pickSupport.clearPickList(); // to ensure entries can be garbage collected
    }
}

protected void doRender(DrawContext dc, OrderedAnnotation oa)
{
    // Swap the draw context's current layer with that of the ordered annotation
    Layer previousCurrentLayer = dc.getCurrentLayer();
    try
    {
        dc.setCurrentLayer(oa.layer);
        oa.annotation.renderNow(dc);
    }
    finally
    {
        dc.setCurrentLayer(previousCurrentLayer); // restore the original layer
    }
}

@Override
public boolean isEnableDecluttering() {
    return (annotation instanceof GlobeAnnotation);
}

@Override
public Rectangle2D getBounds(DrawContext dc) {
    if(annotation instanceof GlobeAnnotation) {
        return ((GlobeAnnotation) annotation).computeBounds(dc);
    }
    return null;
}

}

Answer 1

首先；

Draw order of PointPlacemarks

https://forum.worldwindcentral.com/forum/world-wind-java-forums/development-help/13263-layer-priority-order

在setupAnnotations方法中，您将两个GlobeAnnotation对象的alwaysOnTop设置为true。可能是这个原因。

private void setupAnnotations() {

            // Create an AnnotationLayer with lots of annotations
            this.layer = new AnnotationLayer();

            GlobeAnnotation ga = new GlobeAnnotation("Annotation", Position.fromDegrees(20, -100.9, 1000));
            ga.getAttributes().setTextColor(Color.white);
            ga.getAttributes().setBackgroundColor(Color.BLACK);
            ga.getAttributes().setOpacity(.75f);
            **ga.setAlwaysOnTop(true);**
            layer.addAnnotation(ga);

            ga = new GlobeAnnotation("Annotation", Position.fromDegrees(25, -100.9, 1000));
            ga.getAttributes().setTextColor(Color.white);
            ga.getAttributes().setBackgroundColor(Color.BLACK);
            ga.getAttributes().setOpacity(.75f);
            **ga.setAlwaysOnTop(true);**
            layer.addAnnotation(ga);

            // Add layer to the layer list and update the layer panel
            insertBeforeCompass(this.getWwd(), layer);
        }

相反，通过使用上面的链接，将您希望始终位于顶部的注释放入单独的层中，并将剩余的注释放入另一个层中可能是解决方案。