Zoom in and zoom out code

I am trying to zoom in and zoom out. Below is my code. Can anyone tell me what am I missing as the pointers are moving but zoom in or zoom out is not working:

    PointOption pointFrom = PointOption.point(scrWidth / 2,  scrHeight /2);
    PointOption pointTo = PointOption.point(0,  scrHeight/2);
    PointOption point3 = PointOption.point(scrWidth-50,  scrHeight/2-50);
    TouchAction t1 =new TouchAction<>(driver)
    TouchAction t2 =new TouchAction<>(driver)
            .longPress(PointOption.point(scrWidth / 2-20,  scrHeight /2-20))

I can’t implement this one:“https://appiumpro.com/editions/67-generating-touch-gestures-to-zoom-in-and-out-on-google-maps” because I am working on dialect OSS.

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