用TRIANGLE_FAN绘制三角扇面问题

cailu2121

osg::ref_ptr<osg:rawElementsUshort> draw = new osg::DrawElementsUshort(osg:rimitiveset::TRIANGLE_FAN);
draw->push_back(0);
......
geometry->SetPrimitiveset(draw.get());


为什么生成的图形不是面而是用线连接的呢？

FlySky

可能您的程序设置的问题，给您一段代码，，您对比下：

1. 
   
2. #include <osg/Node>
   
3. #include <osg/Group>
   
4. #include <osg/Geode>
   
5. #include <osg/Geometry>
   
6. #include <osg/Texture2D>
   
7. #include <osgDB/ReadFile>
   
8. #include <osgViewer/Viewer>
   
9. #include <osg/PositionAttitudeTransform>
   
10. #include <osgGA/TrackballManipulator>
    
11. int main()
    
12. {
    
13.         osgViewer::Viewer viewer;
    
14.         osg::Group* root = new osg::Group();
    
15.         osg::Geode* pyramidGeode = new osg::Geode();
    
16.         osg::Geometry* pyramidGeometry = new osg::Geometry();
    
17. 
    
18.         pyramidGeode->addDrawable(pyramidGeometry);
    
19.         root->addChild(pyramidGeode);
    
20. 
    
21.         osg::Vec3Array* pyramidVertices = new osg::Vec3Array;
    
22.         pyramidVertices->push_back( osg::Vec3( 0, 0, 0) );
    
23.         pyramidVertices->push_back( osg::Vec3(10, 0, 0) );
    
24.         pyramidVertices->push_back( osg::Vec3(10,10, 0) );
    
25.         pyramidVertices->push_back( osg::Vec3( 0,10, 0) );
    
26.         pyramidVertices->push_back( osg::Vec3( 5, 5,10) );
    
27. 
    
28.         pyramidGeometry->setVertexArray( pyramidVertices );
    
29. 
    
30. 
    
31.         osg::DrawElementsUShort* pyramidBase =
    
32.                 new osg::DrawElementsUShort(osg::PrimitiveSet::TRIANGLE_FAN);
    
33.         pyramidBase->push_back(4);
    
34.         pyramidBase->push_back(3);
    
35.         pyramidBase->push_back(2);
    
36.         pyramidBase->push_back(1);
    
37.         pyramidBase->push_back(0);
    
38.         pyramidGeometry->addPrimitiveSet(pyramidBase);
    
39. 
    
40.         viewer.setSceneData( root );;
    
41. 
    
42.         viewer.setCameraManipulator(new osgGA::TrackballManipulator());
    
43.         viewer.realize();
    
44. 
    
45.         while( !viewer.done() )
    
46.         {
    
47.                 viewer.frame();
    
48.         }
    
49. 
    
50.         return 0;
    
51. }
    
52. 
    
53. 
    

复制代码