[WP8.1] Get new position, relative to Canvas, of a rotated Rectangle

Question

I am struggling to figure out how i could get the new coordinate of a rotated Rectangle that is inside a Canvas.

My goal is to detect collisions between a non rotated rectangle and a rotated rectangle.

Note: The rotated rectangle is rotated around a canvas point, not its center.

I wanted to experiment with the answer from this question but IntersectWith is not available:
WPF: Collision Detection with Rotated Squares

Any other solution for collision detection would be welcome!

Thanks in advance!

Answer 1

I found out how to get the coordinate of the rotated rectangle relative to the Parent Canvas, however it doesnt consider the rotation.

var transform = target.TransformToVisual(null);
return transform.TransformPoint(new Point(0, 0));

Answer 2

Hi JPSavard,

>>I wanted to experiment with the answer from this question but IntersectWith is not available

Yes, there is no replacement API in WINRT app, there are only two ways:

1) Calculate the bound of rectangle using Transform angle and Rotating center point, this need some mathematical knowledge, like this thread

2) Using VisualTreeHelper.HitTest method the detect the overlapping area: https://msdn.microsoft.com/en-us/library/system.windows.media.visualtreehelper.hittest.aspx

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