OpenScenegraph示例代码问题

时间:2012-06-20 22:33:25

标签: c++ visual-studio 3d openscenegraph

以下代码来自一本书。当我尝试运行它时,它就失败了

osg :: ref_ptr geom = new osg :: Geometry();

并且,输出窗口似乎没有包含有关崩溃原因的大量信息,除了告诉我它确实崩溃了。知道我在下面的代码中做错了什么吗?提前致谢。

当我尝试在Visual Studio 2010(Windows 7 64)

中运行此窗口时出现Windows错误弹出窗口

Windows已在OSGPracticeLab.exe中触发了断点。 这可能是由于堆的损坏,这表明OSGPracticeLab.exe或其加载的任何DLL中存在错误。 这也可能是由于用户在OSGPracticeLab.exe具有焦点时按下F12。 输出窗口可能包含更多诊断信息。

在尝试调试代码时,我能够将问题跟踪到新函数调用。在下面的代码中,似乎跳过了while循环,并且为p返回了一个空值(没有分配内存,所以我的Geometry对象在下面的代码中没有被实例化。

void *__CRTDECL operator new(size_t size) _THROW1(_STD bad_alloc)
        {       // try to allocate size bytes
        void *p;
        while ((p = malloc(size)) == 0)
                if (_callnewh(size) == 0)
                {       // report no memory
                static const std::bad_alloc nomem;
                _RAISE(nomem);
                }

        return (p);
        }

下面是我绘制一些形状和显示的程序。

#include <osg/ShapeDrawable>
#include <osg/Geode>
#include <osgViewer/Viewer> 


int main()
{
    //An octahedron is a polyhedron having eight triangle faces. 
    //It is really a nice example to show why primitive indexing is important
    // we will sketch the octahedron structure now 

    osg::ref_ptr<osg::Vec3Array> vertices = new osg::Vec3Array(6);
    //octahedron has six vertices, each shaed by four triangles.  
    //withe the help of an index array and the osg::DrawElementsUInt class, we can allocate
    //a vertex array with only six elements
    (*vertices)[0].set( 0.0f, 0.0f, 1.0f);
    (*vertices)[1].set(-0.5f,-0.5f, 0.0f);
    (*vertices)[2].set( 0.5f,-0.5f, 0.0f);
    (*vertices)[3].set( 0.5f, 0.5f, 0.0f);
    (*vertices)[4].set(-0.5f, 0.5f, 0.0f);
    (*vertices)[5].set( 0.0f, 0.0f,-1.0f);
    //The osg::DrawElementsUInt accepts a size parameter besides the drawing mode parameter, too. 
    //After that, we will specify the indices of vertices to describe all eight triangle faces.
    osg::ref_ptr<osg::DrawElementsUInt> indices = new osg::DrawElementsUInt(GL_TRIANGLES, 24);
    (*indices)[0] = 0; (*indices)[1] = 1; (*indices)[2] = 2;
    (*indices)[3] = 0; (*indices)[4] = 2; (*indices)[5] = 3;
    (*indices)[6] = 0; (*indices)[7] = 3; (*indices)[8] = 4;
    (*indices)[9] = 0; (*indices)[10]= 4; (*indices)[11]= 1;
    (*indices)[12]= 5; (*indices)[13]= 2; (*indices)[14]= 1;
    (*indices)[15]= 5; (*indices)[16]= 3; (*indices)[17]= 2;
    (*indices)[18]= 5; (*indices)[19]= 4; (*indices)[20]= 3;
    (*indices)[21]= 5; (*indices)[22]= 1; (*indices)[23]= 4;

    //To create a geometry with a default white color, we only set the vertex array 
    //and the osg::DrawElementsUInt primitive set. The normal array is also required but is not easy
    //to compute manually. We will use a smoothed normal calculator to automatically obtain it. This calculator
    //will be described in the next section, Using polygonal techniques.
    osg::ref_ptr<osg::Geometry> geom = new osg::Geometry();
    geom->setVertexArray( vertices.get() );
    geom->addPrimitiveSet( indices.get() );
    //osgUtil::SmoothingVisitor::smooth( *geom );
    //Add the geometry to an osg::Geode object and make it the scene root
    osg::ref_ptr<osg::Geode> root = new osg::Geode;
    root->addDrawable( geom.get() );
    osgViewer::Viewer viewer;
    viewer.setSceneData( root.get() );
    return viewer.run();
}

int drawShapeUsingVertices()
{
    //Create the vertex array and push the four corner points to the back of the array by using vector like operations:
    osg::ref_ptr<osg::Vec3Array> vertices = new osg::Vec3Array;
    vertices->push_back( osg::Vec3(0.0f, 0.0f, 0.0f) );
    vertices->push_back( osg::Vec3(1.0f, 0.0f, 0.0f) );
    vertices->push_back( osg::Vec3(1.0f, 0.0f, 1.0f) );
    vertices->push_back( osg::Vec3(0.0f, 0.0f, 1.0f) );
    //We have to indicate the normal of each vertex; otherwise OpenGL will use a default (0, 0, 1) normal vector
    //and the lighting equation calculation may be incorrect. The four vertices actually face the same direction,
    //so a single normal vector is enough. We will also set the setNormalBinding() method to BIND_OVERALL later.
    osg::ref_ptr<osg::Vec3Array> normals = new osg::Vec3Array; 
    normals->push_back( osg::Vec3(0.0f,-1.0f, 0.0f) );
    osg::ref_ptr<osg::Vec4Array> colors = new osg::Vec4Array;
    //here We will indicate a unique color value to each vertex and make them colored. By default, 
    //OpenGL will use smooth coloring and blend colors at each vertex together:
    colors->push_back( osg::Vec4(1.0f, 0.0f, 0.0f, 1.0f) );
    colors->push_back( osg::Vec4(0.0f, 1.0f, 0.0f, 1.0f) );
    colors->push_back( osg::Vec4(0.0f, 0.0f, 1.0f, 1.0f) );
    colors->push_back( osg::Vec4(1.0f, 1.0f, 1.0f, 1.0f) );
    //Next, we create the osg::Geometry object and set the prepared vertex, normal, and color arrays to it. 
    //We also indicate that the single normal should be bound to the entire geometry and that the colors
    //should be bound per vertex:
    osg::ref_ptr<osg::Geometry> quad = new osg::Geometry;
    quad->setVertexArray( vertices.get() );
    quad->setNormalArray( normals.get() );
    quad->setNormalBinding( osg::Geometry::BIND_OVERALL );
    quad->setColorArray( colors.get() );
    quad->setColorBinding( osg::Geometry::BIND_PER_VERTEX );

    //The last step required to finish a geometry and add it to the scene graph is to specify the primitive set.
    //A newly allocated osg::DrawArrays instance with the drawing mode set to GL_QUADS is used here, in order to
    //render the four vertices as quad corners in a counter-clockwise order:
    quad->addPrimitiveSet( new osg::DrawArrays(GL_QUADS, 0, 4) );
    //Add the geometry to an osg::Geode object and render it in the scene viewer:
    osg::ref_ptr<osg::Geode> root = new osg::Geode;
    root->addDrawable( quad.get() );
    osgViewer::Viewer viewer;
    viewer.setSceneData( root.get() );
    return viewer.run();
}

3 个答案:

答案 0 :(得分:4)

我对代码没有任何问题。从初学者指南中取出它并且工作正常:

#include <osg/Geometry>
#include <osg/Geode>
#include <osgViewer/Viewer>

int main()
{
    osg::ref_ptr<osg::Vec3Array> vertices = new osg::Vec3Array;
    vertices->push_back( osg::Vec3(0.0f, 0.0f, 0.0f) );
    vertices->push_back( osg::Vec3(1.0f, 0.0f, 0.0f) );
    vertices->push_back( osg::Vec3(1.0f, 0.0f, 1.0f) );
    vertices->push_back( osg::Vec3(0.0f, 0.0f, 1.0f) );

    osg::ref_ptr<osg::Vec3Array> normals = new osg::Vec3Array;
    normals->push_back( osg::Vec3(0.0f,-1.0f, 0.0f) );

    osg::ref_ptr<osg::Vec4Array> colors = new osg::Vec4Array;
    colors->push_back( osg::Vec4(1.0f, 0.0f, 0.0f, 1.0f) );
    colors->push_back( osg::Vec4(0.0f, 1.0f, 0.0f, 1.0f) );
    colors->push_back( osg::Vec4(0.0f, 0.0f, 1.0f, 1.0f) );
    colors->push_back( osg::Vec4(1.0f, 1.0f, 1.0f, 1.0f) );

    osg::ref_ptr<osg::Geometry> quad = new osg::Geometry;
    quad->setVertexArray( vertices.get() );
    quad->setNormalArray( normals.get() );
    quad->setNormalBinding( osg::Geometry::BIND_OVERALL );
    quad->setColorArray( colors.get() );
    quad->setColorBinding( osg::Geometry::BIND_PER_VERTEX );

    quad->addPrimitiveSet( new osg::DrawArrays(GL_QUADS, 0, 4) );

    osg::ref_ptr<osg::Geode> root = new osg::Geode;
    root->addDrawable( quad.get() );
    osgViewer::Viewer viewer;
    viewer.setSceneData( root.get() );
    return viewer.run();
}  

我建议您检查项目属性。

您是否添加了其他包含目录:$(OSG_ROOT)\include;$(OSG_SOURCE)\include;$(OSG_ROOT)\include\osg;
如果您处于调试模式,那么您的预处理器定义中是否包含此项? _DEBUG;WIN32;
您是否指定了链接器附加目录:$(OSG_ROOT)\lib
您是否指定了链接器附加依赖项?:osgWidgetd.lib;osgVolumed.lib;osgViewerd.lib;osgUtild.lib;osgTextd.lib;osgTerraind.lib;osgSimd.lib;osgShadowd.lib;osgPresentationd.lib;osgParticled.lib;osgManipulatord.lib;osgGAd.lib;osgFXd.lib;osgDBd.lib;osgd.lib;osgAnimationd.lib;OpenThreadsd.lib;;;;;;kernel32.lib;user32.lib;gdi32.lib;winspool.lib;comdlg32.lib;advapi32.lib;shell32.lib;ole32.lib;oleaut32.lib;uuid.lib;odbc32.lib;odbccp32.lib;%(AdditionalDependencies)
您是否指定了配置属性&gt;调试&gt;工作目录为:$(OSG_ROOT)\bin

如果是极端情况,可能是因为您的Visual Studio安装已损坏。尝试重新安装Visual Studio,如果OSG安装已损坏,请重新安装OSG(从源代码构建)。提到这个是因为我的一个朋友在运行OSG时遇到了问题,因为他的Visual Studio已经损坏了。重新安装修复它。

答案 1 :(得分:2)

osg构建了吗?您是否在OSG中运行“安装”项目?即使你这样做,权限也可以在Win7中加密 - 你可能必须手动安装到Program Files。

上面发布的样本在Win7 / VS 2008 / Win32-Release构建配置上完美编译,针对OSG版本3.1.0构建。我刚刚将OSG解决方案中的一个示例项目中的main替​​换为您上面粘贴的代码,它构建并运行时没有您列出的错误。

我正在使用主干中的OSG - 可能至少是任何预制版之前的次要版本,但如果您的路径等设置正确,它应该可以在预建中使用。当然,您也可以尝试从作者下载的示例开始:http://www.skew-matrix.com/OSGQSG/ - 他们已经正确设置了项目文件等。

答案 2 :(得分:0)

您没有在代码中定义osg::Geometry类,因此最可能的问题是您没有正确链接到 定义的对象或库。< / p>

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