python中的SVG与cairo,opengl和rsvg的交互

我使用Cairo,OpenGL和rsvg渲染了一个包含许多元素的巨大SVG文件.我通过rsvg在开罗表面上绘制svg,并创建OpenGL纹理进行绘制.一切顺利.现在,我必须与SVG中的元素进行交互.例如,我想通过坐标猜测一个元素.我想更改SVG中某些路径的背景.我认为在更改背景的情况下,我可以更改SVG DOM并以某种方式重新呈现SVG的一部分.但是对于命中测试元素,我完全感到尴尬.

那么,是否有一些与SVG交互的python库？是否可以留在cairo和rsvg中,如何自己实现？还是有更好的方法在OpenGL中渲染SVG并在python中与其交互？我想要的只是加载SVG,操纵其DOM并呈现它

解决方法:

我对librsvg不太了解,但是自2005年以来似乎没有进行过更新,因此我倾向于建议使用其他实现.

如果您不依赖标准库之外的任何Python库,则可以将Jython与Batik一起使用.这使您可以添加事件处理程序,以及在渲染后更改DOM.

有关如何使用Java执行此操作的示例,请参见see this link.

这是Jython 2.2.1的快速移植(运行,但未经过全面测试)：

from java.awt.event import WindowAdapter;
from java.awt.event import WindowEvent;

from javax.swing import JFrame;

from org.apache.batik.swing import JSVGCanvas;
from org.apache.batik.swing.svg import SVGLoadEventDispatcherAdapter;
from org.apache.batik.swing.svg import SVGLoadEventDispatcherEvent;
from org.apache.batik.script import Window;

from org.w3c.dom import Document;
from org.w3c.dom import Element;
from org.w3c.dom.events import Event;
from org.w3c.dom.events import EventListener;
from org.w3c.dom.events import EventTarget;

class SVGApplication :

    def __init__(self) :

        class MySVGLoadEventDispatcherAdapter(SVGLoadEventDispatcherAdapter):
            def svgLoadEventDispatcherListener(e):
                # At this time the document is available...
                self.document = self.canvas.getSVGDocument();
                # ...and the window object too.
                self.window = self.canvas.getUpdateManager().getScriptingEnvironment().createWindow();
                # Registers the listeners on the document
                # just before the SVGLoad event is
                # dispatched.
                registerListeners();
                # It is time to pack the frame.
                self.frame.pack();

        def windowAdapter(e): 
            # The canvas is ready to load the base document
            # now, from the AWT thread.
            self.canvas.setURI("doc.svg");

        self.frame = JFrame(windowOpened = windowAdapter, size=(800, 600));

        self.canvas = JSVGCanvas();
        # Forces the canvas to always be dynamic even if the current
        # document does not contain scripting or animation.
        self.canvas.setDocumentState(JSVGCanvas.ALWAYS_DYNAMIC);
        self.canvas.addSVGLoadEventDispatcherListener(MySVGLoadEventDispatcherAdapter()) ;

        self.frame.getContentPane().add(self.canvas);

        self.frame.show()

    def registerListeners(self) :
        # Gets an element from the loaded document.
        elt = self.document.getElementById("elt-id");
        t = elt;

        def eventHandler(e):
            print e, type(e)

            self.window.setTimeout(500,run = lambda : self.window.alert("Delayed Action invoked!"));
            #window.setInterval(Animation(), 50);

        # Adds a 'onload' listener
        t.addEventListener("SVGLoad", false, handleEvent = eventHandler );

        # Adds a 'onclick' listener
        t.addEventListener("click", false, handleEvent = eventHandler );



if __name__ == "__main__":
    SVGApplication();

运行：

jython -Dpython.path=/usr/share/java/batik-all.jar:/home/jacob/apps/batik-1.7/lib/xml-apis-ext.jar test.py

标签：cairo,svg,rsvg,opengl,python
来源： https://codeday.me/bug/20191209/2097181.html