/// <summary>
/// Un-projects a 2D screen point.
/// </summary>
/// <param name="viewport">The viewport.</param>
/// <param name="point2d">The input point.</param>
/// <returns>The ray.</returns>
public static Ray UnProject(this Viewport3DX viewport, Vector2 point2d)//, out Vector3 pointNear, out Vector3 pointFar)
{
var camera = viewport.Camera as ProjectionCamera;
if (camera != null)
{
var px = (float)point2d.X;
var py = (float)point2d.Y;
var viewMatrix = camera.GetViewMatrix();
Vector3 v = new Vector3();
var matrix = CameraExtensions.InverseViewMatrix(ref viewMatrix);
float w = (float)viewport.ActualWidth;
float h = (float)viewport.ActualHeight;
var aspectRatio = w / h;
var projMatrix = camera.GetProjectionMatrix(aspectRatio);
Vector3 zn, zf;
v.X = (2 * px / w - 1) / projMatrix.M11;
v.Y = -(2 * py / h - 1) / projMatrix.M22;
v.Z = 1 / projMatrix.M33;
Vector3.TransformCoordinate(ref v, ref matrix, out zf);
if (camera is PerspectiveCamera)
{
zn = camera.Position.ToVector3();
}
else
{
v.Z = 0;
Vector3.TransformCoordinate(ref v, ref matrix, out zn);
}
Vector3 r = zf - zn;
r.Normalize();
return(new Ray(zn, r));
}
throw new HelixToolkitException("Unproject camera error.");
}
/// <summary>
/// Initial implementation of hittest for billboard. Needs further improvement.
/// </summary>
/// <param name="rayWS"></param>
/// <param name="hits"></param>
/// <returns></returns>
protected override bool OnHitTest(IRenderMatrices context, Ray rayWS, ref List <HitTestResult> hits)
{
var g = this.geometryInternal as IBillboardText;
var h = false;
var result = new HitTestResult();
result.Distance = double.MaxValue;
if (context == null || g.Width == 0 || g.Height == 0)
{
return(false);
}
if (g != null)
{
BoundingBox b = new BoundingBox();
var left = -g.Width / 2;
var right = -left;
var top = -g.Height / 2;
var bottom = -top;
if (FixedSize)
{
var viewportMatrix = context.ViewportMatrix;
var projectionMatrix = context.ProjectionMatrix;
var viewMatrix = context.ViewMatrix;
var visualToScreen = viewMatrix * projectionMatrix * viewportMatrix;
var center = new Vector4(g.Positions[0], 1);
var screenPoint = Vector4.Transform(center, visualToScreen);
var spw = screenPoint.W;
var spx = screenPoint.X;
var spy = screenPoint.Y;
var spz = screenPoint.Z / spw / projectionMatrix.M33;
var matrix = CameraExtensions.InverseViewMatrix(ref viewMatrix);
var width = (float)context.ActualWidth;
var height = (float)context.ActualHeight;
Vector3 v = new Vector3();
var x = spx + left * spw;
var y = spy + bottom * spw;
v.X = (2 * x / width / spw - 1) / projectionMatrix.M11;
v.Y = -(2 * y / height / spw - 1) / projectionMatrix.M22;
v.Z = spz;
Vector3 bl;
Vector3.TransformCoordinate(ref v, ref matrix, out bl);
x = spx + right * spw;
y = spy + bottom * spw;
v.X = (2 * x / width / spw - 1) / projectionMatrix.M11;
v.Y = -(2 * y / height / spw - 1) / projectionMatrix.M22;
v.Z = spz;
Vector3 br;
Vector3.TransformCoordinate(ref v, ref matrix, out br);
x = spx + right * spw;
y = spy + top * spw;
v.X = (2 * x / width / spw - 1) / projectionMatrix.M11;
v.Y = -(2 * y / height / spw - 1) / projectionMatrix.M22;
v.Z = spz;
Vector3 tr;
Vector3.TransformCoordinate(ref v, ref matrix, out tr);
x = spx + left * spw;
y = spy + top * spw;
v.X = (2 * x / width / spw - 1) / projectionMatrix.M11;
v.Y = -(2 * y / height / spw - 1) / projectionMatrix.M22;
v.Z = spz;
Vector3 tl;
Vector3.TransformCoordinate(ref v, ref matrix, out tl);
b = BoundingBox.FromPoints(new Vector3[] { tl, tr, bl, br });
/*
* var visualToScreen = viewport.GetViewProjectionMatrix() * viewport.GetViewportMatrix();
*
* var screenToVisual = visualToScreen.Inverted();
*
* var center = new Vector4(g.Positions[0], 1);
* var screenPoint = Vector4.Transform(center, visualToScreen);
* var spw = screenPoint.W;
* var spx = screenPoint.X;
* var spy = screenPoint.Y;
* var spz = screenPoint.Z;
*
* //Debug.WriteLine(spw);
* // Debug.WriteLine(string.Format("Z={0}; W={1}", spz, spw));
* var bl = new Vector4(spx + left * spw, spy + bottom * spw, spz, spw);
* bl = Vector4.Transform(bl, screenToVisual);
* bl /= bl.W;
*
* var br = new Vector4(spx + right * spw, spy + bottom * spw, spz, spw);
* br = Vector4.Transform(br, screenToVisual);
* br /= br.W;
*
* var tr = new Vector4(spx + right * spw, spy + top * spw, spz, spw);
* tr = Vector4.Transform(tr, screenToVisual);
* tr /= tr.W;
*
* var tl = new Vector4(spx + left * spw, spy + top * spw, spz, spw);
* tl = Vector4.Transform(tl, screenToVisual);
* tl /= tl.W;
*
* b = BoundingBox.FromPoints(new Vector3[] { tl.ToVector3(), tr.ToVector3(), bl.ToVector3(), br.ToVector3() });
*/
}
else
{
var center = new Vector4(g.Positions[0], 1);
var viewMatrix = context.ViewMatrix;
var vcenter = Vector4.Transform(center, viewMatrix);
var vcX = vcenter.X;
var vcY = vcenter.Y;
var bl = new Vector4(vcX + left, vcY + bottom, vcenter.Z, vcenter.W);
var br = new Vector4(vcX + right, vcY + bottom, vcenter.Z, vcenter.W);
var tr = new Vector4(vcX + right, vcY + top, vcenter.Z, vcenter.W);
var tl = new Vector4(vcX + left, vcY + top, vcenter.Z, vcenter.W);
var invViewMatrix = CameraExtensions.InverseViewMatrix(ref viewMatrix);
bl = Vector4.Transform(bl, invViewMatrix);
bl /= bl.W;
br = Vector4.Transform(br, invViewMatrix);
br /= br.W;
tr = Vector4.Transform(tr, invViewMatrix);
tr /= tr.W;
tl = Vector4.Transform(tl, invViewMatrix);
tl /= tl.W;
b = BoundingBox.FromPoints(new Vector3[] { tl.ToVector3(), tr.ToVector3(), bl.ToVector3(), br.ToVector3() });
}
// this all happens now in world space now:
//Debug.WriteLine(string.Format("RayPosition:{0}; Direction:{1};", rayWS.Position, rayWS.Direction));
if (rayWS.Intersects(ref b))
{
float distance;
if (Collision.RayIntersectsBox(ref rayWS, ref b, out distance))
{
h = true;
result.ModelHit = this;
result.IsValid = true;
result.PointHit = (rayWS.Position + (rayWS.Direction * distance)).ToPoint3D();
result.Distance = distance;
Debug.WriteLine(string.Format("Hit; HitPoint:{0}; Bound={1}; Distance={2}", result.PointHit, b, distance));
}
}
}
if (h)
{
hits.Add(result);
}
return(h);
}