safari或retina显示白边修正

[thomashooo]

    const viewport = new WebMercatorViewport({
        // width: gl.drawingBufferWidth*1.11,
        // height: gl.drawingBufferHeight*1.11,
        width: gl.drawingBufferWidth / window.devicePixelRatio,
        height: gl.drawingBufferHeight / window.devicePixelRatio,
        longitude: center.lng,
        latitude: center.lat,
        zoom: currentZoomLevel,
        pitch,
        bearing,
    });

[YuanZeSheng]

devicePixelRatio = 2 的时候， 打点的坐标会偏移