/// <summary>
/// Zoom in/out centered on the specified point (in content coordinates).
/// The focus point is kept locked to it's on screen position (ala google maps).
/// </summary>
public void AnimatedZoomAboutPoint(double newContentScale, Point contentZoomFocus)
{
newContentScale = Math.Min(Math.Max(newContentScale, MinContentScale), MaxContentScale);
ZoomPanAnimationHelper.CancelAnimation(this, ContentZoomFocusXProperty);
ZoomPanAnimationHelper.CancelAnimation(this, ContentZoomFocusYProperty);
ZoomPanAnimationHelper.CancelAnimation(this, ViewportZoomFocusXProperty);
ZoomPanAnimationHelper.CancelAnimation(this, ViewportZoomFocusYProperty);
ContentZoomFocusX = contentZoomFocus.X;
ContentZoomFocusY = contentZoomFocus.Y;
ViewportZoomFocusX = (ContentZoomFocusX - ContentOffsetX) * ContentScale;
ViewportZoomFocusY = (ContentZoomFocusY - ContentOffsetY) * ContentScale;
//
// When zooming about a point make updates to ContentScale also update content offset.
//
_enableContentOffsetUpdateFromScale = true;
ZoomPanAnimationHelper.StartAnimation(this, ContentScaleProperty, newContentScale, AnimationDuration,
delegate(object sender, EventArgs e)
{
_enableContentOffsetUpdateFromScale = false;
ResetViewportZoomFocus();
});
}
/// <summary>
/// Zoom to the specified scale and move the specified focus point to the center of the viewport.
/// </summary>
private void AnimatedZoomPointToViewportCenter(double newContentScale, Point contentZoomFocus, EventHandler callback)
{
newContentScale = Math.Min(Math.Max(newContentScale, MinContentScale), MaxContentScale);
ZoomPanAnimationHelper.CancelAnimation(this, ContentZoomFocusXProperty);
ZoomPanAnimationHelper.CancelAnimation(this, ContentZoomFocusYProperty);
ZoomPanAnimationHelper.CancelAnimation(this, ViewportZoomFocusXProperty);
ZoomPanAnimationHelper.CancelAnimation(this, ViewportZoomFocusYProperty);
ContentZoomFocusX = contentZoomFocus.X;
ContentZoomFocusY = contentZoomFocus.Y;
ViewportZoomFocusX = (ContentZoomFocusX - ContentOffsetX) * ContentScale;
ViewportZoomFocusY = (ContentZoomFocusY - ContentOffsetY) * ContentScale;
//
// When zooming about a point make updates to ContentScale also update content offset.
//
_enableContentOffsetUpdateFromScale = true;
ZoomPanAnimationHelper.StartAnimation(this, ContentScaleProperty, newContentScale, AnimationDuration,
delegate(object sender, EventArgs e)
{
_enableContentOffsetUpdateFromScale = false;
if (callback != null)
{
callback(this, EventArgs.Empty);
}
});
ZoomPanAnimationHelper.StartAnimation(this, ViewportZoomFocusXProperty, ViewportWidth / 2, AnimationDuration);
ZoomPanAnimationHelper.StartAnimation(this, ViewportZoomFocusYProperty, ViewportHeight / 2, AnimationDuration);
}
/// <summary>
/// Use animation to center the view on the specified point (in content coordinates).
/// </summary>
public void AnimatedSnapTo(Point contentPoint)
{
double newX = contentPoint.X - (this.ContentViewportWidth / 2);
double newY = contentPoint.Y - (this.ContentViewportHeight / 2);
ZoomPanAnimationHelper.StartAnimation(this, ContentOffsetXProperty, newX, AnimationDuration);
ZoomPanAnimationHelper.StartAnimation(this, ContentOffsetYProperty, newY, AnimationDuration);
}