public static ARHitTestResult SmartHitTest(this ARSCNView self, CGPoint point)
{
// Perform the hit test.
var results = self.HitTest(point, ARHitTestResultType.ExistingPlaneUsingGeometry);
// 1. Check for a result on an existing plane using geometry.
var existingPlaneUsingGeometryResult = results.FirstOrDefault(result => result.Type == ARHitTestResultType.ExistingPlaneUsingGeometry);
if (existingPlaneUsingGeometryResult != null)
{
return(existingPlaneUsingGeometryResult);
}
// 2. Check for a result on an existing plane, assuming its dimensions are infinite.
var infinitePlaneResults = self.HitTest(point, ARHitTestResultType.ExistingPlane);
var infinitePlaneResult = infinitePlaneResults.FirstOrDefault();
if (infinitePlaneResult != null)
{
return(infinitePlaneResult);
}
// 3. As a final fallback, check for a result on estimated planes.
return(results.FirstOrDefault(result => result.Type == ARHitTestResultType.EstimatedHorizontalPlane));
}
public void TapAction(UITapGestureRecognizer gestureRecognizer)
{
var location = gestureRecognizer.LocationOfTouch(0, scnView);
var hits = scnView.HitTest(location, new SCNHitTestOptions());
if (hits.Count() != 0)
{
var tappedNodeName = hits.FirstOrDefault().Node.Name;
UIAlertView alert = new UIAlertView()
{
Title = tappedNodeName,
Message = "You found a " + tappedNodeName
};
alert.AddButton("OK");
alert.Show();
}
}
private static SCNVector3?HitTestExistingPlanes(CGPoint point, ARSCNView sceneView)
{
var hitResult = sceneView.HitTest(point, ARHitTestResultType.ExistingPlaneUsingExtent);
if (hitResult.Count() > 0)
{
var xPos = hitResult[0].WorldTransform.Column3.X;
var yPos = hitResult[0].WorldTransform.Column3.Y;
var zPos = hitResult[0].WorldTransform.Column3.Z;
return(new SCNVector3(xPos, yPos, zPos));
}
return(null);
}
//Getting world position from touch hit
Tuple <SCNVector3?, ARAnchor> WorldPositionFromHitTest(CGPoint pt)
{
//Hit test against existing anchors
var hits = scnView.HitTest(pt, ARHitTestResultType.ExistingPlaneUsingExtent);
if (hits != null && hits.Length > 0)
{
var anchors = hits.Where(r => r.Anchor is ARPlaneAnchor);
if (anchors.Count() > 0)
{
var first = anchors.First();
var pos = PositionFromTransform(first.WorldTransform);
return(new Tuple <SCNVector3?, ARAnchor>(pos, (ARPlaneAnchor)first.Anchor));
}
}
return(new Tuple <SCNVector3?, ARAnchor>(null, null));
}
internal static ARHitTestResult SmartHitTest(this ARSCNView self, CGPoint point)
{
var hitTestResults = self.HitTest(point, ARHitTestResultType.FeaturePoint);
if (hitTestResults == null || hitTestResults.Length == 0)
{
return(null);
}
foreach (var result in hitTestResults)
{
// Return the first result which is between 20 cm and 3 m away from the user.
if (result.Distance > 0.2 && result.Distance < 3)
{
return(result);
}
}
return(null);
}
private void HandleTap(UITapGestureRecognizer recognizer)
{
var tapLocation = recognizer.LocationInView(sceneView);
var hitTestResults = sceneView.HitTest(tapLocation, ARHitTestResultType.ExistingPlaneUsingExtent);
if (hitTestResults != null && hitTestResults.Length > 0)
{
var hitTestResult = hitTestResults[0];
var translation = PositionFromTransform(hitTestResult.WorldTransform);
var x = translation.X;
var y = translation.Y;
var z = translation.Z;
var shipScene = SCNScene.FromFile("Sprites/ship.scn");
var shipNode = shipScene.RootNode.FindChildNode("ship", false);
shipNode.Position = new SCNVector3(x, y, z);
sceneView.Scene.RootNode.AddChildNode(shipNode);
}
}
public override void TouchesBegan(Foundation.NSSet touches, UIEvent evt)
{
if (touches.Count != 0)
{
var touch = touches.ToArray <UITouch>()[0];
var location = touch.LocationInView(sceneView);
var hitList = sceneView.HitTest(location, new SCNHitTestOptions());
if (hitList.Length > 0)
{
var hitObject = hitList[0];
if (hitObject.Node.Name == "ARShip")
{
hitObject.Node.RemoveFromParentNode();
AddObject();
}
}
}
}
internal (SCNVector3?, ARPlaneAnchor, Boolean) WorldPositionFromScreenPosition(CGPoint position, ARSCNView sceneView, SCNVector3?objectPos, bool infinitePlane = false)
{
var dragOnInfinitePlanesEnabled = AppSettings.DragOnInfinitePlanes;
// -------------------------------------------------------------------------------
// 1. Always do a hit test against exisiting plane anchors first.
// (If any such anchors exist & only within their extents.)
var planeHitTestResults = sceneView.HitTest(position, ARHitTestResultType.ExistingPlaneUsingExtent);
var result = planeHitTestResults.FirstOrDefault();
if (result != null)
{
var planeHitTestPosition = result.WorldTransform.Translation();
var planeAnchor = result.Anchor;
return(planeHitTestPosition, (ARPlaneAnchor)planeAnchor, true);
}
// -------------------------------------------------------------------------------
// 2. Collect more information about the environment by hit testing against
// the feature point cloud, but do not return the result yet.
SCNVector3?featureHitTestPosition = null;
var highQualityFeatureHitTestResult = false;
var highQualityfeatureHitTestResults = sceneView.HitTestWithFeatures(position, 18, 0.2, 2.0);
if (highQualityfeatureHitTestResults.Count() > 0)
{
var highQualityFeatureHit = highQualityfeatureHitTestResults.First();
featureHitTestPosition = highQualityFeatureHit.Position;
highQualityFeatureHitTestResult = true;
}
// -------------------------------------------------------------------------------
// 3. If desired or necessary (no good feature hit test result): Hit test
// against an infinite, horizontal plane (ignoring the real world).
if ((infinitePlane && dragOnInfinitePlanesEnabled) || !highQualityFeatureHitTestResult)
{
if (objectPos.HasValue)
{
var pointOnInfinitePlane = sceneView.HitTestWithInfiniteHorizontalPlane(position, objectPos.Value);
if (pointOnInfinitePlane != null)
{
return(pointOnInfinitePlane, null, true);
}
}
}
// -------------------------------------------------------------------------------
// 4. If available, return the result of the hit test against high quality
// features if the hit tests against infinite planes were skipped or no
// infinite plane was hit.
if (highQualityFeatureHitTestResult)
{
return(featureHitTestPosition, null, false);
}
// -------------------------------------------------------------------------------
// 5. As a last resort, perform a second, unfiltered hit test against features.
// If there are no features in the scene, the result returned here will be nil.
var unfilteredFeatureHitTestResults = sceneView.HitTestWithFeatures(position);
if (unfilteredFeatureHitTestResults.Count() > 0)
{
var unfilteredFeaturesResult = unfilteredFeatureHitTestResults.First();
return(unfilteredFeaturesResult.Position, null, false);
}
return(null, null, false);
}
public static (SCNVector3?, ARPlaneAnchor, bool) WorldPositionFromScreenPosition(CGPoint position,
ARSCNView sceneView,
SCNVector3?objectPos,
bool infinitePlane = false)
{
// -------------------------------------------------------------------------------
// 1. Always do a hit test against existing plane anchors first.
// (If any such anchors exist & only within their extents.)
var result = sceneView.HitTest(position, ARHitTestResultType.ExistingPlaneUsingExtent)?.FirstOrDefault();
if (result != null)
{
var planeHitTestPosition = result.WorldTransform.GetTranslation();
var planeAnchor = result.Anchor;
// Return immediately - this is the best possible outcome.
return(planeHitTestPosition, planeAnchor as ARPlaneAnchor, true);
}
// -------------------------------------------------------------------------------
// 2. Collect more information about the environment by hit testing against
// the feature point cloud, but do not return the result yet.
SCNVector3?featureHitTestPosition = null;
var highQualityFeatureHitTestResult = false;
var highQualityfeatureHitTestResults = sceneView.HitTestWithFeatures(position, 18f, 0.2f, 2f);
if (highQualityfeatureHitTestResults.Any())
{
featureHitTestPosition = highQualityfeatureHitTestResults[0].Position;
highQualityFeatureHitTestResult = true;
}
// -------------------------------------------------------------------------------
// 3. If desired or necessary (no good feature hit test result): Hit test
// against an infinite, horizontal plane (ignoring the real world).
if (infinitePlane || !highQualityFeatureHitTestResult)
{
if (objectPos.HasValue)
{
var pointOnInfinitePlane = sceneView.HitTestWithInfiniteHorizontalPlane(position, objectPos.Value);
if (pointOnInfinitePlane.HasValue)
{
return(pointOnInfinitePlane, null, true);
}
}
}
// -------------------------------------------------------------------------------
// 4. If available, return the result of the hit test against high quality
// features if the hit tests against infinite planes were skipped or no
// infinite plane was hit.
if (highQualityFeatureHitTestResult)
{
return(featureHitTestPosition, null, false);
}
// -------------------------------------------------------------------------------
// 5. As a last resort, perform a second, unfiltered hit test against features.
// If there are no features in the scene, the result returned here will be nil.
var unfilteredFeatureHitTestResults = sceneView.HitTestWithFeatures(position);
if (unfilteredFeatureHitTestResults.Any())
{
var first = unfilteredFeatureHitTestResults[0];
return(first.Position, null, false);
}
return(null, null, false);
}
