/// <summary>
/// Zooms the camera to the specified rectangle.
/// </summary>
/// <param name="camera">
/// The camera.
/// </param>
/// <param name="viewport">
/// The viewport.
/// </param>
/// <param name="zoomRectangle">
/// The zoom rectangle.
/// </param>
public static void ZoomToRectangle(this CameraCore camera, ViewportCore viewport, RectangleF zoomRectangle)
{
if (camera is ProjectionCameraCore pcam)
{
if (viewport.UnProject(new Vector2(zoomRectangle.Top, zoomRectangle.Left), out var topLeftRay) &&
viewport.UnProject(new Vector2(zoomRectangle.Top, zoomRectangle.Right), out var topRightRay) &&
viewport.UnProject(
new Vector2(
(zoomRectangle.Left + zoomRectangle.Right) * 0.5f,
(zoomRectangle.Top + zoomRectangle.Bottom) * 0.5f), out var centerRay))
{
var u = topLeftRay.Direction;
var v = topRightRay.Direction;
var w = centerRay.Direction;
u.Normalize();
v.Normalize();
w.Normalize();
if (camera is PerspectiveCameraCore perspectiveCamera)
{
var distance = pcam.LookDirection.Length();
// option 1: change distance
var newDistance = distance * zoomRectangle.Width / viewport.ViewportRectangle.Width;
var newLookDirection = (float)newDistance * w;
var newPosition = perspectiveCamera.Position + ((distance - (float)newDistance) * w);
var newTarget = newPosition + newLookDirection;
LookAt(pcam, newTarget, newLookDirection, 200);
}
else if (camera is OrthographicCameraCore orthographicCamera)
{
orthographicCamera.Width *= zoomRectangle.Width / viewport.ViewportRectangle.Width;
var oldTarget = pcam.Position + pcam.LookDirection;
var distance = pcam.LookDirection.Length();
if (centerRay.PlaneIntersection(oldTarget, w, out var newTarget))
{
orthographicCamera.LookDirection = w * distance;
orthographicCamera.Position = newTarget - orthographicCamera.LookDirection;
}
}
}
}
}
/// <summary>
///
/// </summary>
/// <param name="viewport"></param>
/// <param name="point2d"></param>
/// <returns></returns>
public static Ray UnProjectToRay(this ViewportCore viewport, Vector2 point2d)
{
var r = viewport.UnProject(point2d);
return(new Ray(r.Position, r.Direction));
}
