So I am using ARKit and ARAnchors in an ARImageTrackingConfiguration(). I am using multiple versions of the same ARAnchor with different colored backgrounds. I would like to be able to get the background color of the ARAnchor being recognized (because if I register them all as ARAnchors it mixes them up even if they have different backgrounds). The way I was thinking of doing this was to get the position of the ARAnchor in 2D space and then obtaining the color of a pixel within the frame like this.
The problem is I can't find a way to get the ARAnchor's position in 2D space. I am using a setup like below. If you have any idea how I can translate the coordinates or a better way to do this please let me know.
func renderer(_ renderer: SCNSceneRenderer, nodeFor anchor: ARAnchor) -> SCNNode? {
let node = SCNNode()
if let imageAnchor = anchor as? ARImageAnchor {
if (anchor.name == "EXAMPLE MARKER") {
let plane = SCNPlane(width: imageAnchor.referenceImage.physicalSize.width, height: imageAnchor.referenceImage.physicalSize.height)
plane.firstMaterial?.diffuse.contents = UIImage(named: "EXAMPLE")
let planeNode = SCNNode(geometry: plane)
planeNode.eulerAngles.x = -.pi / 2
node.addChildNode(planeNode)
// HOW TO CONVERT ANY OF THESE COORDINATE SYSTEMS TO GRECT? CGPOINT?
}
}
return node
}
I've tried to get the position as follows but it always comes out as all zeros
print(anchor.accessibilityFrame)
print(imageAnchor.accessibilityFrame)
print(node.frame)
print(node.boundingBox.max,node.boundingBox.min)
Results
(0.0, 0.0, 0.0, 0.0)
(0.0, 0.0, 0.0, 0.0)
(0.0, 0.0, 0.0, 0.0)
SCNVector3(x: 0.0, y: 0.0, z: 0.0) SCNVector3(x: 0.0, y: 0.0, z: 0.0)
Related
I'm trying to detect an image using ARImageTrackingConfiguration and when the image is detected, an UIWebView shows up instead of the image scanned. I read a lot of problems regarding the new WBWebView but is not working either.
The problem it seems that is the UIWebView is not being updated from the main thread even thought I'm using the DispatchMain.
On a related topic (the code I use is pretty much the same), if I try to put a SKVideoNode instead of a UIWebView, the video gets played super laggy with some big pixels on top if I set plane.cornerRadius = 0.25
The code is the following
func renderer(_ renderer: SCNSceneRenderer, didAdd node: SCNNode, for anchor: ARAnchor) {
guard let imageAnchor = anchor as? ARImageAnchor else { return }
updateQueue.async {
let physicalWidth = imageAnchor.referenceImage.physicalSize.width
let physicalHeight = imageAnchor.referenceImage.physicalSize.height
// Create a plane geometry to visualize the initial position of the detected image
let mainPlane = SCNPlane(width: physicalWidth, height: physicalHeight)
mainPlane.firstMaterial?.colorBufferWriteMask = .alpha
// Create a SceneKit root node with the plane geometry to attach to the scene graph
// This node will hold the virtual UI in place
let mainNode = SCNNode(geometry: mainPlane)
mainNode.eulerAngles.x = -.pi / 2
mainNode.renderingOrder = -1
mainNode.opacity = 1
// Add the plane visualization to the scene
node.addChildNode(mainNode)
// Perform a quick animation to visualize the plane on which the image was detected.
// We want to let our users know that the app is responding to the tracked image.
self.highlightDetection(on: mainNode, width: physicalWidth, height: physicalHeight, completionHandler: {
DispatchQueue.main.async {
let request = URLRequest(url: URL(string: "https://www.facebook.com/")!)
let webView = UIWebView(frame: CGRect(x: 0, y: 0, width: 400, height: 672))
webView.loadRequest(request)
let webViewPlane = SCNPlane(width: xOffset, height: xOffset * 1.4)
webViewPlane.cornerRadius = 0.25
let webViewNode = SCNNode(geometry: webViewPlane)
webViewNode.geometry?.firstMaterial?.diffuse.contents = webView
webViewNode.position.z -= 0.5
webViewNode.opacity = 0
rootNode.addChildNode(webViewNode)
webViewNode.runAction(.sequence([
.wait(duration: 3.0),
.fadeOpacity(to: 1.0, duration: 1.5),
.moveBy(x: xOffset * 1.1, y: 0, z: -0.05, duration: 1.5),
.moveBy(x: 0, y: 0, z: -0.05, duration: 0.2)
])
)
}
})
}
}
VIDEO VERSION
func renderer(_ renderer: SCNSceneRenderer, didAdd node: SCNNode, for anchor: ARAnchor) {
guard let imageAnchor = anchor as? ARImageAnchor else { return }
updateQueue.async {
let physicalWidth = imageAnchor.referenceImage.physicalSize.width
let physicalHeight = imageAnchor.referenceImage.physicalSize.height
// Create a plane geometry to visualize the initial position of the detected image
let mainPlane = SCNPlane(width: physicalWidth, height: physicalHeight)
mainPlane.firstMaterial?.colorBufferWriteMask = .alpha
// Create a SceneKit root node with the plane geometry to attach to the scene graph
// This node will hold the virtual UI in place
let mainNode = SCNNode(geometry: mainPlane)
mainNode.eulerAngles.x = -.pi / 2
mainNode.renderingOrder = -1
mainNode.opacity = 1
// Add the plane visualization to the scene
node.addChildNode(mainNode)
// Perform a quick animation to visualize the plane on which the image was detected.
// We want to let our users know that the app is responding to the tracked image.
self.highlightDetection(on: mainNode, width: physicalWidth, height: physicalHeight, completionHandler: {
let size = imageAnchor.referenceImage.physicalSize
var videoNode = SKVideoNode()
switch imageAnchor.name {
case "Elephant-PostCard":
videoNode = SKVideoNode(fileNamed: "Movies/cat.mp4")
case "puppy":
videoNode = SKVideoNode(fileNamed: "puppy.mov")
default:
break
}
// invert our video so it does not look upside down
videoNode.yScale = -1.0
videoNode.play()
let videoScene = SKScene(size: CGSize(width: 1280, height: 720))
videoScene.anchorPoint = CGPoint(x: 0.5, y: 0.5)
videoScene.addChild(videoNode)
let plane = SCNPlane(width: size.width, height: size.height)
plane.cornerRadius = 0.25
plane.firstMaterial?.diffuse.contents = videoScene
let planeNode = SCNNode(geometry: plane)
plane.firstMaterial?.isDoubleSided = true
mainNode.addChildNode(planeNode)
})
}
}
UIWebView from UIKit module is now deprecated.
Use WKWebView from WebKit module instead.
I am trying to rotate by scene kit node, however it is not rotating.
I want it to rotate around the y axis. It is a sphere.
let node = SCNNode()
node.geometry = SCNSphere(radius: 1)
node.geometry?.firstMaterial?.diffuse.contents = UIImage(named: "diffuse.png")
node.geometry?.firstMaterial?.specular.contents = UIImage(named: "specular.png")
node.geometry?.firstMaterial?.emission.contents = UIImage(named: "emission.png")
scene.rootNode.addChildNode(node)
let action = SCNAction.rotate(by:360 * CGFloat((Double.pi)/180.0), around: SCNVector3(x: 0, y: 1, z: 0), duration: 8)
let repeatAction = SCNAction.repeatForever(action)
node.runAction(repeatAction)
Are you certain it isn't rotating? I'm not sure what your diffuse, specular and emission images are but maybe because it's a sphere it just doesn't really look like it is rotating because it looks the same from all sides.
Running the same action on a cube in viewDidAppear is working for me, so it could just be that you can't really notice the sphere rotating. I used this code:
let node = SCNNode()
node.geometry = SCNBox (width: 0.5, height: 0.5, length: 0.5, chamferRadius: 0.1)
node.position = SCNVector3Make(0, 0, -1)
sceneView.scene.rootNode.addChildNode(node)
let action = SCNAction.rotate(by:360 * CGFloat((Double.pi)/180.0), around: SCNVector3(x: 0, y: 1, z: 0), duration: 8)
let repeatAction = SCNAction.repeatForever(action)
node.runAction(repeatAction)
The cube is rotating fine with the way that you rotated the SCNNode.
Hope this helps
I am using this to create a simple 3D object in Single View application. In a default configuration, the following code places a 10-centimeter cube 20 centimeters in front of the camera's initial position
let cubeNode = SCNNode(geometry: SCNBox(width: 0.1, height: 0.1, length: 0.1, chamferRadius: 0))
cubeNode.position = SCNVector3(0, 0, -0.2)
sceneView.scene.rootNode.addChildNode(cubeNode)
When plane detection is enabled, ARKit adds and updates anchors for each detected plane. To add visual content for these anchors, implement
ARSCNViewDelegate methods such as the following:
func renderer(_ renderer: SCNSceneRenderer, didAdd node: SCNNode, for anchor: ARAnchor) {
guard let planeAnchor = anchor as? ARPlaneAnchor else { return }
let plane = SCNPlane(width: CGFloat(planeAnchor.extent.x), height: CGFloat(planeAnchor.extent.z))
let planeNode = SCNNode(geometry: plane)
planeNode.position = SCNVector3Make(planeAnchor.center.x, 0, planeAnchor.center.z)
planeNode.transform = SCNMatrix4MakeRotation(-Float.pi / 2, 1, 0, 0)
node.addChildNode(planeNode)
}
How can i rander the 3D Object.
The code below generates a red box in a SCNView. However, the edges are jagged along the top and bottom of the side/element facing you (as illustrated by the attachment). The goal is to render smoother edges similar to Minecraft boxes. Changing the camera position reduces the pixelation of certain edges, so is this a camera angle issue? If yes, is it possible to render boxes with smooth edges no matter the camera angle?
For instance setting the camera position to SCNVector3(x: 0.0, y: 0.0, z: 10.0) renders the box effectively in 2D and with crisp edges (second attachment).
let sceneView = SCNView(frame: self.view.frame)
self.view.addSubview(sceneView)
let scene = SCNScene()
sceneView.scene = scene
let camera = SCNCamera()
let cameraNode = SCNNode()
cameraNode.camera = camera
cameraNode.position = SCNVector3(x: -3.0, y: 0.0, z: 10.0)
let ambientLight = SCNLight()
ambientLight.type = SCNLightTypeAmbient
ambientLight.color = UIColor(red: 0.2, green: 0.2, blue: 0.2, alpha: 1.0)
cameraNode.light = ambientLight
let light = SCNLight()
light.type = SCNLightTypeOmni
let lightNode = SCNNode()
lightNode.light = light
lightNode.position = SCNVector3(x: 0, y: 20, z: 10)
let cubeGeometry = SCNBox(width: 3.0, height: 3.0, length: 3.0, chamferRadius: 0.0)
let cubeNode = SCNNode(geometry: cubeGeometry)
let planeGeometry = SCNPlane(width: 100.0, height: 100.0)
let planeNode = SCNNode(geometry: planeGeometry)
planeNode.eulerAngles = SCNVector3(x: GLKMathDegreesToRadians(-90), y: 0, z: 0)
planeNode.position = SCNVector3(x: 0, y: -0.5, z: 0)
let redMaterial = SCNMaterial()
redMaterial.diffuse.contents = UIColor.redColor()
cubeGeometry.materials = [redMaterial]
let greenMaterial = SCNMaterial()
greenMaterial.diffuse.contents = UIColor.greenColor()
planeGeometry.materials = [greenMaterial]
let constraint = SCNLookAtConstraint(target: cubeNode)
constraint.gimbalLockEnabled = true
cameraNode.constraints = [constraint]
lightNode.constraints = [constraint]
scene.rootNode.addChildNode(lightNode)
scene.rootNode.addChildNode(cameraNode)
scene.rootNode.addChildNode(cubeNode)
scene.rootNode.addChildNode(planeNode)
As mentioned in the comments, if you want to antialias every frame set the antialiasingMode. It doesn’t do as nice a job as CoreGraphics but it’s reasonably nice. However, it does increase the workload a ton, so you’re going to burn batteries and slow down your framerate.
On OS X the default is to 4x multisample every frame. On iOS the default is no multisampling, since it’s so expensive.
Luckily there’s a solution I much prefer, which is to turn on jittering. It’s kind of like multisampling but lazy. When objects are moving they are rendered normally (with jaggies), but when they stop moving the renderer runs like 96 more frames in the background and smooths out all the jaggies.
The final look is much better than antialiasing (because there’s no “96x antialiasing mode”) and on fast hardware most people I’ve shown it to don’t realize that the quality is changing when objects move.
I am tying to draw a 3d line in Scenekit iOS, i am trying below code to draw line,
func path() -> UIBezierPath
{
var bPath = UIBezierPath()
bPath.moveToPoint(CGPointMake(0, 0))
bPath.addLineToPoint(CGPointMake(10, 10))
bPath.addLineToPoint(CGPointMake(5, 5))
bPath.closePath()
return bPath
}
and the below code is to load the line in SCNNode,
let sap = SCNShape()
sap.path = path()
let carbonNode = SCNNode(geometry: sap)
carbonNode.position = SCNVector3Make(0, 0, 15)
scene.rootNode.addChildNode(carbonNode)
But, i am getting blank screen.
try changing your geometry's materials. You might have a white object on a white background.
edit:
it also turns out that the vertices of your triangle are colinear. You thus end up with a degenerate triangle.
Your path has no surface area since you start at (0,0), draw a line to (10, 10) and then a second line to (5,5) which is already on the line between (0,0) and (10, 10). Then you close the path by drawing another line to (0,0).
Changing either of the three points creates a path with a surface area.
Also, the z-axis points out of the screen. This means that depending on where your camera is positioned, you may be placing the carbonNode behind the camera. If instead you meant to position it further into the scene you should likely use a negative z value.
Here's some code I wrote to address the problem.
// Material colors
let cyanMaterial = SCNMaterial()
cyanMaterial.diffuse.contents = UIColor.cyanColor()
let anOrangeMaterial = SCNMaterial()
anOrangeMaterial.diffuse.contents = UIColor.orangeColor()
let aPurpleMaterial = SCNMaterial()
aPurpleMaterial.diffuse.contents = UIColor.purpleColor()
// A bezier path
let bezierPath = UIBezierPath()
bezierPath.moveToPoint(CGPointMake(-0.25, 0))
bezierPath.addLineToPoint(CGPointMake(0, -0.25))
bezierPath.addLineToPoint(CGPointMake(0.25, 0))
bezierPath.addLineToPoint(CGPointMake(0, 0.25))
bezierPath.closePath()
// Add shape
let shape = SCNShape(path: bezierPath, extrusionDepth: 0.75)
shape.materials = [cyanMaterial, anOrangeMaterial, aPurpleMaterial]
let shapeNode = SCNNode(geometry: shape)
shapeNode.position = SCNVector3(x: 0.2, y: 0.75, z: 0.1);
self.rootNode.addChildNode(shapeNode)
shapeNode.rotation = SCNVector4(x: -1.0, y: -1.0, z: 0.0, w: 0.0)
Keep in mind that the numbers, the Scene Kit scale, are in meters. So set the numbers similarly to those that work for the other shapes you create.