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我想要将几个对象合并成一个场景图。从Geode有两套Geode的翘曲场景
Street继承并取得了GL_LINE_STRIP的Geometry孩子绘制。Pointer继承自PositionAttitudeTransform并且包含Geode，其包含两个Geometry多边形。
当我添加一堆街道到Group，它看起来很好。当我只将指针添加到Group时，它看起来也很好。但是如果我在场景中以某种方式拥有它们，那么第二个就会搞砸了。看到两张照片。
在上述画面，街道网络作为期望的话，并且在下面的图片，指针是任意的。
我会很感激任何帮助！如果您需要查看代码，请告诉我，我会更新我的问题。
更新1：由于到目前为止没有发生任何事情，因此下面是生成该现象所需的最少量代码。我已经把两个指针放在一起，没有问题，所以我开始怀疑我弄错了街道......下一次更新将会是一些街道代的代码。
更新2：该代码现在包含街道绘图代码。
更新3：该代码现在还包含指针绘图代码，并且街道图 代码已被简化。
// My libraries:
#include <asl/util/color.h>
using namespace asl;
#include <straph/point.h>
#include <straph/straph.h>
using namespace straph;
// Standard and OSG libraries:
#include <utility>
#include <boost/tuple/tuple.hpp> // tie
using namespace std;
#include <osg/ref_ptr>
#include <osg/Array>
#include <osg/Geometry>
#include <osg/Geode>
#include <osg/Group>
#include <osg/LineWidth>
using namespace osg;
#include <osgUtil/Tessellator>
#include <osgViewer/Viewer>
using namespace osgViewer;
/*
* Just FYI: A Polyline looks like this:
*
* typedef std::vector<Point> Polyline;
*
* And a Point basically is a simple struct:
*
* struct Point {
* double x;
* double y;
* };
*/
inline osg::Vec3d toVec3d(const straph::Point& p, double elevation=0.0)
{
return osg::Vec3d(p.x, p.y, elevation);
}
Geometry* createStreet(const straph::Polyline& path)
{
ref_ptr<Vec3dArray> array (new Vec3dArray(path.size()));
for (unsigned i = 0; i < path.size(); ++i) {
(*array)[i] = toVec3d(path[i]);
}
Geometry* geom = new Geometry;
geom->setVertexArray(array.get());
geom->addPrimitiveSet(new osg::DrawArrays(GL_LINE_STRIP, 0, array->size()));
return geom;
}
Geode* load_streets()
{
unique_ptr<Straph> graph = read_shapefile("mexico/roads", 6);
Geode* root = new Geode();
boost::graph_traits<straph::Straph>::edge_iterator ei, ee;
for (boost::tie(ei, ee) = edges(*graph); ei != ee; ++ei) {
const straph::Segment& s = (*graph)[*ei];
root->addDrawable(createStreet(s.polyline));
}
return root;
}
Geode* createPointer(double width, const Color& body_color, const Color& border_color)
{
float f0 = 0.0f;
float f3 = 3.0f;
float f1 = 1.0f * width;
float f2 = 2.0f * width;
// Create vertex array
ref_ptr<Vec3Array> vertices (new Vec3Array(4));
(*vertices)[0].set( f0 , f0 , f0);
(*vertices)[1].set(-f1/f3, -f1/f3 , f0);
(*vertices)[2].set( f0 , f2/f3 , f0);
(*vertices)[3].set( f1/f3, -f1/f3 , f0);
// Build the geometry object
ref_ptr<Geometry> polygon (new Geometry);
polygon->setVertexArray(vertices.get());
polygon->addPrimitiveSet(new DrawArrays(GL_POLYGON, 0, 4));
// Set the colors
ref_ptr<Vec4Array> body_colors (new Vec4Array(1));
(*body_colors)[0] = body_color.get();
polygon->setColorArray(body_colors.get());
polygon->setColorBinding(Geometry::BIND_OVERALL);
// Start the tesselation work
osgUtil::Tessellator tess;
tess.setTessellationType(osgUtil::Tessellator::TESS_TYPE_GEOMETRY);
tess.setWindingType(osgUtil::Tessellator::TESS_WINDING_ODD);
tess.retessellatePolygons(*polygon);
// Create the border-lines
ref_ptr<Geometry> border (new Geometry);
border->setVertexArray(vertices.get());
border->addPrimitiveSet(new DrawArrays(GL_LINE_LOOP, 0, 4));
border->getOrCreateStateSet()->setAttribute(new LineWidth(2.0f));
ref_ptr<Vec4Array> border_colors (new Vec4Array(1));
(*border_colors)[0] = border_color.get();
border->setColorArray(border_colors.get());
border->setColorBinding(Geometry::BIND_OVERALL);
// Create Geode object
ref_ptr<Geode> geode (new Geode);
geode->addDrawable(polygon.get());
geode->addDrawable(border.get());
return geode.release();
}
int main(int, char**)
{
Group* root = new Group();
Geode* str = load_streets();
root->addChild(str);
Geode* p = createPointer(6.0, TangoColor::Scarlet3, TangoColor::Black);
root->addChild(p);
Viewer viewer;
viewer.setSceneData(root);
viewer.getCamera()->setClearColor(Color(TangoColor::White).get());
viewer.run();
}