Hi, I'm playing now with hand tracking. I want to get position of hand inside a system update function. I was not sure if transform I'm getting from hand attached AnchorEntity (with trackingMode: .predicted) would give same results as handAnchors(at:) from hand tracking provider, so I started to read them both and compare. For handAnchors i tried using context.scene.timebase.sourceTimebase!.sourceClock!.time.seconds and CACurrentMediaTime() as timestamp source. They seem to use exactly same clock, so that doesn't matter, but: for some reason update handler is always called twice with same context.deltaTime, but first time the query finds 0 entities, second time it finds them all. The query is the standard EntityQuery(where: .has(MyComponent.self)) and in update (matching: Self.query, updatingSystemWhen: .rendering). Here's part of logs: System update called, entity count: 0, dt: 0.01000458374619484, absTime: 4654.222593541 System update called, entity count: 11, dt: 0.01000458374619484, absTime: 4654.22262525 System update called, entity count: 0, dt: 0.009999999776482582, absTime: 4654.249390875 System update called, entity count: 11, dt: 0.009999999776482582, absTime: 4654.249425 accounting for the double update calling I started to calculate time delta of absolute time between calls and they're most of the time much bigger, or much smaller than advertised by system's context.deltaTime, only sometimes they kind of match, for example: system: (dt: 0.01000458374619484) scene : (dt: 0.021419291667371) (absTime: 4654.222628125001) and the very next call system: (dt: 0.010009 166784584522) scene : (dt: 0.0013097083328830195) (absTime: 4654.223937833334) but sometimes system: (dt: 0.009999999776482582) scene : (dt: 0.009 112249999816413) (absTime: 4654.351299 166668) Shouldn't those be more or less equal, or am I missing something? In the end it seems that getting hand position from AnchorEntity and with handAnchors(at:) gives kind of same results, but at different time points, so I'd love to understand what's the correct way to use them and why time flows differently :). --Edit-- P.S. Had to put spaces everywhere in logs between "9" and "1", otherwise post was blocked due to "sensitive content" :D

Hi, I'm working with CameraFrameProvider from Enterprise API. Is it always capped at 30fps, or is there something I can switch to get more? I assume it is capped at 30, so let me cram in additional question here :). If I'd get a developer strap and attach an external camera capable of doing >30fps, will I get the full stream, or some other limitation will kick in?

Hi, I'm trying to correct the lens distortion in frames provided by Enterprise API camera frame provider. The frames provided seem to have only in/extrinsics info, but not the distortion lookup table. Is there some magic setting, or function to do that (I can't seem to find anything like this)? Or is there a way to use AVCameraCalibrationData together with provider?

To set the stage: I made a prototype of an app for a company, the app is to be used internally right now. Prototype runs perfectly on iOS, so now I got VP to port the app to its final destination. The first thing I found out is that the image tracking on VP is useless for moving images (and that's the core of my app). Also distance at which image is lost seems to be way shorter on VP. Now I'm trying to figure out if it's possible to fix/work around it in any way and I'm wondering if Enterprise API would change anything. So: Is it possible to request Enterprise API access as a single person with basic Apple Developer subscription? I looked around the forum and only got more confused. Does QR code detection and tracking work any better than image detection, or anchor updates are the same? Does the increased "object detection" frequency affect in any way image/QR tracking, or is it (as name implies) only for object tracking? Would increasing the CPU/GPU headroom make any change to image/QR detection frequency? Is there something to disable to make anchor updates more frequent? I don't need complex models, shadows, physics, etc. Greetings Michal

I'm trying to clone an entity that's somewhere deeper in hierarchy and I want it together with transform that takes into account parents. Initially I made something that would go back through parents, get their transforms and then reduce them to single one. Then I realized that what I'm doing is same as .transformMatrix(relativeTo: rootEntity), but to validate that what I made gives same results I started to print them both and I noticed that for some reason the last row instead of stable (0,0,0,1) is sometimes (0,0,0,0.9999...). I know that there are rounding errors, but I'd assume that 0 and 1 are "magical" in FP world. The only way I can try to explain it, is that .transformMatrix is using some fancy accelerated matrix multiplication and those produce some bigger rounding errors. That would explain slight differences in other fields between my version and function call, but still - the 1 seems weird. Here's function I'm using to compare: func cloneFlattened(entity: Entity, withChildren recursive: Bool) -> Entity { let clone = entity.clone(recursive: recursive) var transforms = [entity.transform.matrix] var parent: Entity? = entity.parent var rootEntity: Entity = entity while parent != nil { rootEntity = parent! transforms.append(parent!.transform.matrix) parent = parent!.parent } if transforms.count > 1 { clone.transform.matrix = transforms.reversed().reduce(simd_diagonal_matrix(simd_float4(repeating: 1)), *) print("QWE CLONE FLATTENED: \(clone.transform.matrix)") print("QWE CLONE RELATIVE : \(entity.transformMatrix(relativeTo: rootEntity))") } else { print("QWE CLONE SINGLE : \(clone.transform.matrix)") } return clone } Sometimes last one is not 1 QWE CLONE FLATTENED: [ [0.00042261832, 0.0009063079, 0.0, 0.0], [-0.0009063079, 0.00042261832, 0.0, 0.0], [0.0, 0.0, 0.0010000002, 0.0], [-0.0013045187, -0.009559666, -0.04027118, 1.0] ] QWE CLONE RELATIVE : [ [0.00042261826, 0.0009063076, -4.681872e-12, 0.0], [-0.0009063076, 0.00042261826, 3.580335e-12, 0.0], [3.4256328e-12, 1.8047965e-13, 0.0009999998, 0.0], [-0.0013045263, -0.009559661, -0.040271178, 0.9999997] ] Sometimes it is QWE CLONE FLATTENED: [ [0.0009980977, -6.1623556e-05, -1.7382005e-06, 0.0], [-6.136851e-05, -0.0009958588, 6.707259e-05, 0.0], [-5.8642554e-06, -6.683835e-05, -0.0009977464, 0.0], [-1.761913e-06, -0.002, 0.0, 1.0] ] QWE CLONE RELATIVE : [ [0.0009980979, -6.1623556e-05, -1.7382023e-06, 0.0], [-6.136855e-05, -0.0009958589, 6.707254e-05, 0.0], [-5.864262e-06, -6.6838256e-05, -0.0009977465, 0.0], [-1.758337e-06, -0.0019999966, -3.7252903e-09, 1.0] ] 0s in last row seem to be stable. It happens both for entities that are few levels deep and those that have only anchor as parent. So far I've never seen any value that would not be "technically a 1", but my hierarchies are not very deep and it makes me wonder if this rounding could get worse. Or is it just me doing something stupid? :)