C++ GLUTWindowRefPtr::getPort方法代码示例

//.........这里部分代码省略.........
        SLOG << "Got " << (isPOT?"":"non-") << "power-of-two images and "
            << (hasNPOT?"can":"cannot") << " use NPOT textures, changing "
            << (changeOnlyPart?"part":"all")
            << " of the screen"
            << std::endl;

        // Ok, now for the meat of the code...
        // first we need an Image to hold the picture(s) to show
        image = OSG::Image::create();

        // set the image's size and type, and allocate memory
        // this example uses RGB. On some systems (e.g. Windows) BGR
        // or BGRA might be faster, it depends on how the images are
        // acquired

        image->set(OSG::Image::OSG_RGB_PF, width, height);



        // Now create the texture to be used for the background
        texObj = OSG::TextureObjChunk::create();

        // Associate image and texture
        texObj->setImage(image);

        // Set filtering modes. LINEAR is cheap and good if the image size
        // changes very little (i.e. the window is about the same size as
        // the images).

        texObj->setMinFilter(GL_LINEAR);
        texObj->setMagFilter(GL_LINEAR);

        // Set the wrapping modes. We don't need repetition, it might actually
        // introduce artifactes at the borders, so switch it off.

        texObj->setWrapS(GL_CLAMP_TO_EDGE);
        texObj->setWrapT(GL_CLAMP_TO_EDGE);

        // Newer versions of OpenGL can handle NPOT textures directly.
        // OpenSG will do that internally automatically.
        //
        // Older versions need POT textures. By default OpenSG
        // will scale an NPOT texture to POT while defining it.
        // For changing textures that's too slow.
        // So tell OpenSG not to scale the image and adjust the texture
        // coordinates used by the TextureBackground (see below).

        texObj->setScale(false);

        // Create the background

        OSG::TextureBackgroundRefPtr back = OSG::TextureBackground::create();

        // Set the texture to use
        back->setTexture(texObj);

        // if the image is NPOT and we don't have hardware support for it
        // adjust the texture coordinates.
        if(isPOT == false && hasNPOT == false)
        {
            OSG::UInt32 potWidth  = OSG::osgNextPower2(width );
            OSG::UInt32 potHeight = OSG::osgNextPower2(height);

            OSG::Real32 tcRight = OSG::Real32(width ) / OSG::Real32(potWidth );
            OSG::Real32 tcTop   = OSG::Real32(height) / OSG::Real32(potHeight);

            back->editMFTexCoords()->push_back(OSG::Vec2f(    0.f,   0.f));
            back->editMFTexCoords()->push_back(OSG::Vec2f(tcRight,   0.f));
            back->editMFTexCoords()->push_back(OSG::Vec2f(tcRight, tcTop));
            back->editMFTexCoords()->push_back(OSG::Vec2f(    0.f, tcTop));
        }

        OSG::commitChanges();

        // create the SimpleSceneManager helper
        mgr = OSG::SimpleSceneManager::create();

        // tell the manager what to manage
        mgr->setWindow(gwin );
        mgr->setRoot  (scene);
        mgr->setStatistics(true);

        // replace the background
        // This has to be done after the viewport has been created, which the
        // SSM does in setRoot().

        OSG::ViewportRefPtr vp = gwin->getPort(0);

        vp->setBackground(back);
    }

    // show the whole scene
    mgr->showAll();

    // GLUT main loop
    glutMainLoop();

    return 0;

}