JavaFX2中的大型画布问题

Question

我的应用程序有一个非常大的Canvas，放在一个ScrollPane中。

当JavaFX处理Canvas操作时，大约在1000万像素左右，会抛出这些空指针异常：

at com.sun.javafx.sg.prism.NGCanvas$RenderBuf.validate(Unknown Source)
at com.sun.javafx.sg.prism.NGCanvas.initCanvas(Unknown Source)
at com.sun.javafx.sg.prism.NGCanvas.renderContent(Unknown Source)
at com.sun.javafx.sg.prism.NGNode.doRender(Unknown Source)
at com.sun.javafx.sg.prism.NGNode.doRender(Unknown Source)
at com.sun.javafx.sg.BaseNode.render(Unknown Source)
at com.sun.javafx.sg.prism.NGGroup.renderContent(Unknown Source)
at com.sun.javafx.sg.prism.NGRegion.renderContent(Unknown Source)
at com.sun.javafx.sg.prism.NGNode.doRender(Unknown Source)
at com.sun.javafx.sg.prism.NGNode.doRender(Unknown Source)
at com.sun.javafx.sg.BaseNode.render(Unknown Source)
at com.sun.javafx.sg.prism.NGGroup.renderContent(Unknown Source)
at com.sun.javafx.sg.prism.NGRegion.renderContent(Unknown Source)
at com.sun.javafx.sg.prism.NGNode.renderForClip(Unknown Source)
at com.sun.javafx.sg.prism.NGNode.renderRectClip(Unknown Source)
at com.sun.javafx.sg.prism.NGNode.renderClip(Unknown Source)
at com.sun.javafx.sg.prism.NGNode.doRender(Unknown Source)
at com.sun.javafx.sg.prism.NGNode.doRender(Unknown Source)
at com.sun.javafx.sg.BaseNode.render(Unknown Source)
at com.sun.javafx.sg.prism.NGGroup.renderContent(Unknown Source)
at com.sun.javafx.sg.prism.NGRegion.renderContent(Unknown Source)
at com.sun.javafx.sg.prism.NGNode.doRender(Unknown Source)
at com.sun.javafx.sg.prism.NGNode.doRender(Unknown Source)
at com.sun.javafx.sg.BaseNode.render(Unknown Source)
at com.sun.javafx.sg.prism.NGGroup.renderContent(Unknown Source)
at com.sun.javafx.sg.prism.NGNode.doRender(Unknown Source)
at com.sun.javafx.sg.prism.NGNode.doRender(Unknown Source)
at com.sun.javafx.sg.BaseNode.render(Unknown Source)
at com.sun.javafx.sg.prism.NGGroup.renderContent(Unknown Source)
at com.sun.javafx.sg.prism.NGRegion.renderContent(Unknown Source)
at com.sun.javafx.sg.prism.NGNode.doRender(Unknown Source)
at com.sun.javafx.sg.prism.NGNode.doRender(Unknown Source)
at com.sun.javafx.sg.BaseNode.render(Unknown Source)
at com.sun.javafx.tk.quantum.ViewPainter.doPaint(Unknown Source)
at com.sun.javafx.tk.quantum.AbstractPainter.paintImpl(Unknown Source)
at com.sun.javafx.tk.quantum.PresentingPainter.run(Unknown Source)
at java.util.concurrent.Executors$RunnableAdapter.call(Unknown Source)
at java.util.concurrent.FutureTask.runAndReset(Unknown Source)
at com.sun.prism.render.RenderJob.run(Unknown Source)
at java.util.concurrent.ThreadPoolExecutor.runWorker(Unknown Source)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source)
at com.sun.javafx.tk.quantum.QuantumRenderer$PipelineRunnable.run(Unknown Source)
at java.lang.Thread.run(Unknown Source)

我认为解决方案必须是虚拟化画布(Canvas)。我想象这在概念上类似于ListView的实现。

如果您了解类似于此的示例或任何可提供指导的页面，请告诉我。(Virtual和virtualized似乎不是用于谷歌搜索此主题的有用关键词)

谢谢

- John Cashew

---

请使用最近的JavaFX版本，例如8u20，它对此方面进行了一些错误修复：RT-36571 Re-enable DirectX 9Ex to avoid losing textures when surface lost。请参阅相关论坛讨论：Canvas Rendering Degrades Proportionally With Size?，以及ControlsFX GridView（不同于eppleton TileEngine，它不特定于画布）。 - jewelsea

这些是好链接。谢谢。 - John Cashew

Answer 1

我们遇到了相同的问题。为什么会发生这种情况，可以在这里找到解释：https://community.oracle.com/thread/3549359 我们绕过了视频卡并使用以下JVM参数解决了这个问题：-Dprism.order=sw 您可能还想使用-Xmx增加堆内存，因为它会使用更多的内存。

- Chocksmith