[Résolu] Effectuer le zoom réelle sous Android

Zoomer mZoomer;
private PointF mZoomFocalPoint = new PointF();
...

// If a zoom is in progress (either programmatically or via double
// touch), performs the zoom.
if (mZoomer.computeZoom()) {
    float newWidth = (1f - mZoomer.getCurrZoom()) * 
            mScrollerStartViewport.width();
    float newHeight = (1f - mZoomer.getCurrZoom()) * 
            mScrollerStartViewport.height();
    float pointWithinViewportX = (mZoomFocalPoint.x - 
            mScrollerStartViewport.left)
            / mScrollerStartViewport.width();
    float pointWithinViewportY = (mZoomFocalPoint.y - 
            mScrollerStartViewport.top)
            / mScrollerStartViewport.height();
    mCurrentViewport.set(
            mZoomFocalPoint.x - newWidth * pointWithinViewportX,
            mZoomFocalPoint.y - newHeight * pointWithinViewportY,
            mZoomFocalPoint.x + newWidth * (1 - pointWithinViewportX),
            mZoomFocalPoint.y + newHeight * (1 - pointWithinViewportY));
    constrainViewport();
    needsInvalidate = true;
}
if (needsInvalidate) {
    ViewCompat.postInvalidateOnAnimation(this);
}