3 Replies
      Latest reply: Oct 10, 2017 4:29 AM by Yaali RSS
      Yaali Level 1 Level 1 (0 points)

        I am working on an application using ARKit-Scenekit. I am able to render my 3D object, create overlay etc. I want to load a gif animation like a overlay in ARSession on tap of one of my child nodes. Is this possible?

        I tried adding SKScene as a overlay to my SCNScene like below, and it looks good.

        informationOverlay = InformationOverlayScene(size: self.sceneView.frame.size) self.sceneView.overlaySKScene = informationOverlay

        But how to load this gif file in SKScene or SCNNode?

        • Re: How to load a gif animation in ARSession using ARKit-Scenekit?
          TonyPham Level 2 Level 2 (80 points)

          For me, I used some free websites to convert the gif file into multi-frame-images, then store them as an atlas, load them into a SKTextureAtlas, use SKAction to run those frames as an animation within a SKSpriteNode. Now you can use that sprite node to work as an overlay or as a material for ScnNode.



          That way works well in my app (ARDraw)

            • Re: How to load a gif animation in ARSession using ARKit-Scenekit?
              Yaali Level 1 Level 1 (0 points)

              I followed CALayer approach to solve this. Upon tapping a child node i am displaying a gif image by creating animation using CALayer and loading it in diffuse.contents

                          let animation : CAKeyframeAnimation = createGIFAnimation(url: gifImageURL!)!

                          let layer = CALayer()

                          layer.bounds = CGRect(x: 0, y: 0, width:600, height:200)

                          layer.add(animation, forKey: "contents")

                          let newMaterial = SCNMaterial()

                          newMaterial.isDoubleSided = true

                          newMaterial.diffuse.contents = layer

                          let plane = SCNPlane(width: 5, height: 5)

                          plane.materials = [newMaterial]

                          let node = SCNNode(geometry: plane)


              I am able to render the gif image in SCNNode but it is displaying only half of it(Right bottom most portion of gif is only visible). I tried below steps to rectify this but still in vain

              • Changing Plane's width/height
              • Changing the bounds of CALayer
              • Tried with different sizes of gif image
            • Re: How to load a gif animation in ARSession using ARKit-Scenekit?
              Bobjt Apple Staff Apple Staff (60 points)

              SpriteKit currently does not support loading of animated .gif (nor .apng). At the moment, you use Image I/O to turn gif frames into individual UIImages, and from there into SKSpriteNodes or SKTextures. The example (in Objective-C but the Swift version is symantically equivalent):


              NSURL* url = [NSURL fileURLWithPath:self.filename];
              numberOfImages = (int)CGImageSourceGetCount( imgSrc );
              for( int i = 0; i < numberOfImages; ++i ) {
                   @autoreleasepool {             
                        CGImageRef cgImage = CGImageSourceCreateImageAtIndex( imgSrc, i, nil );               
                        UIImage* frame = [UIImage imageWithCGImage:cgImage];
                        CGImageRelease( cgImage );
                        [self.images addObject:result];
              CFRelease( imgSrc );