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Qt3D - Video Texture



  • Hello everybody!
    I'm creating a 3D scene in C++ via 3D render module.
    I'm not using any qml file, just C++.

    I sucessfuly got a 3d scene with my custom object in it. Everything was going fine but now i think i hit the wall...

    I need to set an image texture on my object.... the problem is that it should update quickly ( video texture )....
    I got the image there but i can only load it at costruct time since it needs a QUrl.... but my intention is to use a Opencv frame ( cv::Mat) is there any workaround on it? (I think writtig a png and load for each frame will grill the computer!)
    I searched alot on Qt Material classes and none of them AFAIK supports it.... I sucessfully got the Mat to QImage....but there's no way to use QImage aswell.... Abstract texture was good but only accepts QUrl.

    Any workarounds or feedback would be appreciated thanks!

    I will leave some snippets of my code

    Where I need to load the frame texture from opencv...

        // screen
        m_screenEntity = new Qt3DCore::QEntity(m_rootEntity);
        // screen shape data
        screenMesh = new Qt3DExtras::QPlaneMesh(m_screenEntity);
        screenMesh->setWidth(0.6);
        screenMesh->setHeight(0.23);
    
        // screen mesh transform
        screenTransform = new Qt3DCore::QTransform(m_screenEntity);
        screenTransform->setScale(1.3f);
        screenTransform->setRotation(QQuaternion::fromAxisAndAngle(QVector3D(1.0f, 0.0f, 0.0f), 90.0f));
        screenTransform->setTranslation(QVector3D(posx, posy, posz+ screenoffset));
    
        //screen material
        screenMaterial = new Qt3DExtras::QPhongMaterial(m_screenEntity);
        screenMaterial->setDiffuse(QColor(QRgb(0xa69929)));
    

    The frame processing

            Mat frame;
            // Capture frame-by-frame
            this->cap >> frame;
    
            // If the frame is empty, break immediately
            if (frame.empty())
                break;
    
            // Display the resulting frame --> should update object texture instead
            imshow("Frame", frame); 
    
            // Press  ESC on keyboard to exit
            char c = (char)waitKey(25);
            if (c == 27)
                break;
        }
    

    thanks,
    André


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