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Opengl world coords change on camera rotation

  • Hi,

    I build own gluUnProject, but I have big trouble with camera, when I rotate camera, world coords are changed and are incorrect.

    When I just start app, my Z coordinate is incorrect, when I turn camera to left by 90 degrees, Z is in normal, but X is corrupted.

    @ QMatrix4x4 viewMatrix = m_camera->viewMatrix();
    QMatrix4x4 modelViewMatrix = viewMatrix * m_modelMatrix;
    QMatrix4x4 modelViewProject = m_camera->projectionMatrix() * modelViewMatrix;
    QMatrix4x4 inverted = m_viewportMatrix * modelViewProject;

        inverted = inverted.inverted();
        float posZ;
        int   posY = (int)m_viewportSize.y() - (int)mouse_position.y() - 1;
        m_funcs->glReadPixels((int)mouse_position.x(), posY, 1, 1, GL_DEPTH_COMPONENT, GL_FLOAT, &posZ);
        QVector4D clickedPointOnScreen(mouse_position.x(), (float)posY, posZ, 1.0f);
        QVector4D clickedPointIn3DOrgn = inverted * clickedPointOnScreen;
        clickedPointIn3DOrgn = clickedPointIn3DOrgn / clickedPointIn3DOrgn.w();
        terrain_pos = clickedPointIn3DOrgn.toVector3DAffine();@

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