message: Start removing stray nalgebra types from public API
  See issue for the list.  This one cleans up `graphics`,
  I think.
diff: @@ -65,8 +65,8 @@ impl Rect {
  }
  /// Gets the `Rect`'s x and y coordinates as a `Point2`.
  - pub fn point(&self) -> Point2 {
  - Point2::new(self.x, self.y)
  + pub fn point(&self) -> mint::Point2<f32> {
  + mint::Point2{ x: self.x, y: self.y}
  }
  /// Returns the left edge of the `Rect`
  @@ -90,7 +90,8 @@ impl Rect {
  }
  /// Checks whether the `Rect` contains a `Point`
  - pub fn contains(&self, point: Point2) -> bool {
  + pub fn contains<P>(&self, point: P) -> bool where P: Into<mint::Point2<f32>> {
  + let point = point.into();
  point.x >= self.left()
  && point.x <= self.right()
  && point.y <= self.bottom()
  @@ -106,13 +107,15 @@ impl Rect {
  }
  /// Translates the `Rect` by an offset of (x, y)
  - pub fn translate(&mut self, offset: Vector2) {
  + pub fn translate<V>(&mut self, offset: V) where V: Into<mint::Vector2<f32>> {
  + let offset = offset.into();
  self.x += offset.x;
  self.y += offset.y;
  }
  /// Moves the `Rect`'s origin to (x, y)
  - pub fn move_to(&mut self, destination: Point2) {
  + pub fn move_to<P>(&mut self, destination: P) where P: Into<mint::Point2<f32>> {
  + let destination = destination.into();
  self.x = destination.x;
  self.y = destination.y;
  }
  