Finding the correct scale value within a scaled object to maintain the aspect ratio of a video

I have a video inside of another movieclip. When I go full screen, I scale up the outer movieclip to fit the screen. So that OuterMovieClip.width is equal to screenWidth etc. How do I maintain the aspect ratio on my video so it does not get distorted开发者_如何学Go? Whats the proper math for that?

Thank you.

I believe you'd need something (code below untested) along the lines of...

var screen_aspect_ratio = Screen.Width / Screen.Height;
var outer_aspect_ratio = OuterMovieClip.Width / OuterMovieClip.Height;
var new_outer_width;
var new_outer_height;

if (screen_aspect_ratio > outer_aspect_ratio) {
  new_outer_height = Screen.Height;
  new_outer_width = (Screen.Height * OuterMovieClip.Width) / OuterMovieClip.Height;
} else {
  new_outer_width = Screen.Width;
  new_outer_height = (Screen.Width * OuterMovieClip.Height) / OuterMovieClip.Width;
}

OuterMovieClip.Width = new_outer_width;
OuterMovieClip.Height = new_outer_height;