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我想在 QGLWidget 中显示 OptixSDK 的 sample6。

我的应用程序只有 3 个用于围绕 X、Y、Z 轴和 QGLWidget 旋转的 QSlider。

据我了解,每当我的 QSlider 或 Mouseevents调用 updateGL ()时,都会调用paintGL() 。然后我初始化一个旋转矩阵并将这个矩阵应用到 PinholeCamera 以便使用新的变换后的相机坐标来跟踪场景,对吧?

跟踪完成后,我得到输出缓冲区并使用它使用glDrawPixels()绘制像素,就像在 OptiX 框架中给出的 GLUTdisplay.cpp 中一样。

但我的问题是图像歪斜/扭曲。例如,我想展示一个球,但球是极端扁平的,但旋转效果很好。当我缩小时,图像的水平缩放似乎比垂直缩放慢得多。

我几乎可以肯定/希望它必须对未正确使用的gl...()函数做一些事情。我错过了什么?有人可以帮我吗?

为了完整起见,我发布了我的paintGL()updateGL()代码。

void MyGLWidget::initializeGL()
{
glPixelStorei(GL_UNPACK_ALIGNMENT, 1);
m_scene = new MeshViewer();
m_scene->setMesh( (std::string( sutilSamplesDir() ) + "/ball.obj").c_str());                                  
int buffer_width, buffer_height;
    // Set up scene
    SampleScene::InitialCameraData initial_camera_data;
    m_scene->setUseVBOBuffer( false );
    m_scene->initScene( initial_camera_data );
    int m_initial_window_width = 400;
    int m_initial_window_height = 400;

    if( m_initial_window_width > 0 && m_initial_window_height > 0)
        m_scene->resize( m_initial_window_width, m_initial_window_height );

   // Initialize camera according to scene params
    m_camera = new PinholeCamera( initial_camera_data.eye,
                                  initial_camera_data.lookat,
                                  initial_camera_data.up,
                                  -1.0f, // hfov is ignored when using keep vertical
                                  initial_camera_data.vfov,
                                  PinholeCamera::KeepVertical );

    Buffer buffer = m_scene->getOutputBuffer();
    RTsize buffer_width_rts, buffer_height_rts;
    buffer->getSize( buffer_width_rts, buffer_height_rts );

    buffer_width  = static_cast<int>(buffer_width_rts);
    buffer_height = static_cast<int>(buffer_height_rts);

    float3 eye, U, V, W;
    m_camera->getEyeUVW( eye, U, V, W );
    SampleScene::RayGenCameraData camera_data( eye, U, V, W );

    // Initial compilation
    m_scene->getContext()->compile();
    // Accel build
    m_scene->trace( camera_data );
    m_scene->getContext()->launch( 0, 0 );

    // Initialize state
    glMatrixMode(GL_PROJECTION);glLoadIdentity();glOrtho(0, 1, 0, 1, -1, 1 );
    glMatrixMode(GL_MODELVIEW); glLoadIdentity();  glViewport(0, 0, buffer_width, buffer_height); 
   }

这是paintGL()

void MyGLWidget::paintGL()
{
glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
glLoadIdentity();
    float3 eye, U, V, W;
    m_camera->getEyeUVW( eye, U, V, W );
    SampleScene::RayGenCameraData camera_data( eye, U, V, W );

    {
        nvtx::ScopedRange r( "trace" );
        m_scene->trace( camera_data );
    }
    // Draw the resulting image
    Buffer buffer = m_scene->getOutputBuffer();
    RTsize buffer_width_rts, buffer_height_rts;
    buffer->getSize( buffer_width_rts, buffer_height_rts );
    int buffer_width  = static_cast<int>(buffer_width_rts);
    int buffer_height = static_cast<int>(buffer_height_rts);
    RTformat buffer_format = buffer.get()->getFormat();

    GLvoid* imageData = buffer->map();
    assert( imageData );
    switch (buffer_format) {
    /*... set gl_data_type and gl_format ...*/
    }

    RTsize elementSize = buffer->getElementSize();
    int align = 1;
    if      ((elementSize % 8) == 0) align = 8;
    else if ((elementSize % 4) == 0) align = 4;
    else if ((elementSize % 2) == 0) align = 2;
    glPixelStorei(GL_UNPACK_ALIGNMENT, align);

    gldata = QGLWidget::convertToGLFormat(image_data);

    NVTX_RangePushA("glDrawPixels");
    glDrawPixels( static_cast<GLsizei>( buffer_width ), static_cast<GLsizei>( buffer_height ),gl_format, gl_data_type, imageData);
    // glDraw
    NVTX_RangePop();
    buffer->unmap();
}
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1 回答 1

2

经过数小时的调试,我发现我忘了正确设置相机参数,它与 OpenGL 的东西无关。

我的 U 坐标,视平面的水平轴搞砸了,但 V、W 和眼睛坐标是正确的。

在我在initializeGL()中添加这些行之后

m_camera->setParameters(initial_camera_data.eye,
                        initial_camera_data.lookat,
                        initial_camera_data.up,
                        initial_camera_data.vfov,
                        initial_camera_data.vfov,
                        PinholeCamera::KeepVertical );

一切都是正确的。

于 2015-05-26T09:40:41.163 回答