Hello. In the iOS app i'm working on we are very tight on memory budget and I was looking at ways to reduce our texture memory usage. However I noticed that comparing ASTC8x8 to ASTC12x12, there is no actual difference in allocated memory for most of our textures despite ASTC12x12 having less than half the bpp of 8x8. The difference between the two only becomes apparent for textures 1024x1024 and larger, and even in that case the actual texture data is sometimes only 60% of the allocation size. I understand there must be some alignment and padding going on, but this seems extreme. For an example scene in my app with astc12x12 for most textures there is over a 100mb difference in astc size on disk versus when loaded, so I would love to be able to recover even a portion of that memory.
Here is some test code with some measurements i've taken using an iphone 11:
for(int i = 0; i < 11; i++) {
MTLTextureDescriptor *texDesc = [[MTLTextureDescriptor alloc] init];
texDesc.pixelFormat = MTLPixelFormatASTC_12x12_LDR;
int dim = 12;
int n = 2 << i;
int mips = i+1;
texDesc.width = n;
texDesc.height = n;
texDesc.mipmapLevelCount = mips;
texDesc.resourceOptions = MTLResourceStorageModeShared;
texDesc.usage = MTLTextureUsageShaderRead;
// Calculate the equivalent astc texture size
int blocks = 0;
if(mips == 1) {
blocks = n/dim + (n%dim>0? 1 : 0);
blocks *= blocks;
} else {
for(int j = 0; j < mips; j++) {
int a = 2 << j;
int cur = a/dim + (a%dim>0? 1 : 0);
blocks += cur*cur;
}
}
auto tex = [objCObj newTextureWithDescriptor:texDesc];
printf("%dx%d, mips %d, Astc: %d, Metal: %d\n", n, n, mips, blocks*16, (int)tex.allocatedSize);
}
MTLPixelFormatASTC_12x12_LDR
128x128, mips 7, Astc: 2768, Metal: 6016
256x256, mips 8, Astc: 10512, Metal: 32768
512x512, mips 9, Astc: 40096, Metal: 98304
1024x1024, mips 10, Astc: 158432, Metal: 262144
128x128, mips 1, Astc: 1936, Metal: 4096
256x256, mips 1, Astc: 7744, Metal: 16384
512x512, mips 1, Astc: 29584, Metal: 65536
1024x1024, mips 1, Astc: 118336, Metal: 147456
MTLPixelFormatASTC_8x8_LDR
128x128, mips 7, Astc: 5488, Metal: 6016
256x256, mips 8, Astc: 21872, Metal: 32768
512x512, mips 9, Astc: 87408, Metal: 98304
1024x1024, mips 10, Astc: 349552, Metal: 360448
128x128, mips 1, Astc: 4096, Metal: 4096
256x256, mips 1, Astc: 16384, Metal: 16384
512x512, mips 1, Astc: 65536, Metal: 65536
1024x1024, mips 1, Astc: 262144, Metal: 262144
I also tried using MTLHeaps (placement and automatic) hoping they might be better, but saw nearly the same numbers.
Is there any way to have metal allocate these textures in a more compact way to save on memory?
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I recently needed to develop an application to obtain the window list, which requires Screen Recording permissions. Apple's official documentation mentions using the two functions CGPreflightScreenCaptureAccess and CGRequestScreenCaptureAccess to request permissions. These functions are stated to be available since version 10.15. However, when I used these two functions on a device running macOS 10.15.7, I encountered the errors shown in the attached screenshot. I used the nm tool to inspect the symbols in the CoreGraphics.framework and found that these two functions were not present. Could you help me understand why this is happening?
Topic:
Graphics & Games
SubTopic:
General
Looks like is something to do with the code and that is why my images are distorted. please help me get to the right person to help me get this issue resolved
Topic:
Graphics & Games
SubTopic:
General
Question:
I'm encountering an issue with in-app purchases (IAP) in Unity, specifically for a non-consumable product in the iOS sandbox environment. Below are the details:
Environment:
Unity Version: 2022.3.55f1 Unity In-App Purchasing
Version: v4.12.2
Device: iPhone (15, iOS 18.1.1)
Connection: Wi-Fi iOS
Settings: In-App Purchases set to “Allowed” initially Problem Behavior:
I attempted to purchase a non-consumable item for the first time. The payment is successfully completed by entering the password.
I then background the game app and navigate to the iOS Settings to set In-App Purchases to "Don't Allow."
After returning to the game and either closing or killing the app, I try to purchase the same non-consumable item again.
I checked canMakePayments() through the Apple configuration, and the app correctly detected that I could not make purchases due to the restriction.
I then navigate back to Settings and set In-App Purchases to "Allow."
Upon returning to the game, I try purchasing the non-consumable item again. A pop-up appears, saying, "You’ve already purchased this. Would you like to get it again for free?"
The issue is: Will it deduct money for the second time, and why is the system allowing the user to purchase the same non-consumable item multiple times after purchasing it once?
Is this the expected behavior for Unity In-App Purchasing, or is there something I might be missing in handling non-consumable purchases in this scenario?
Additional Information:
I’ve confirmed that the "In-App Purchases" are set to “Allowed” before attempting the purchase again.
I understand that non-consumable products should not be purchased more than once, so I’m unsure why the system is offering to let the user purchase it again.
I appreciate any insights into whether this is expected behavior or if I need to adjust how I handle the purchase flow.
The code is pretty simple
kernel void naive(
constant RunParams *param [[ buffer(0) ]],
const device float *A [[ buffer(1) ]], // [N, K]
device float *output [[ buffer(2) ]],
uint2 gid [[ thread_position_in_grid ]]) {
uint a_ptr = gid.x * param->K;
for (uint i = 0; i < param->K; i++, a_ptr++) {
val += A[b_ptr];
}
output[ptr] = val;
}
when uint a_ptr = gid.x * param->K, the code got 150 GFLops
when uint a_ptr = gid.y * param->K, the code got 860 GFLops
param->K = 256;
thread per group: [16, 16]
I'd like to understand why the performance is so different, and how can I profile/diagnose this to help with further optimization.
Topic:
Graphics & Games
SubTopic:
Metal
The farther away the center of a large entity is, the less accurate the positioning is?
For example I am changing only the y-axis position of an entity that is tens of meters long, but i notice x and z drifting slowly the farther away the center of the entity is. I would not expect the x and z to move.
It might be compounding rounding errors somewhere, or maybe the RealityKit engine is deciding not to be super precise about distant objects? Otherwise I just have a bug somewhere.
Topic:
Graphics & Games
SubTopic:
RealityKit
RealityKit spatial audio crackles and pops on iOS 26.0 beta 5.
It works correctly on iOS 18.6 and visionOS 26.0 beta 5.
The APIs used are AudioPlaybackController, Entity.prepareAudio, Entity.play
Videos of the expected and observed behavior are attached to the feedback FB19423059.
The audio should be a consistent, repeating sound, but it seems oddly abbreviated and the volume varies unexpectedly.
Thank you for investigating this issue.
Hello Apple team,
I'm working on an iOS AR app using SwiftUI and RealityKit,
and I was wondering if the Cinematic API can be used with a RealityKit scene. I’d like to achieve a shallow depth of field while keeping the 3D asset in focus, and vice versa.
Thanks!
We have a macOS app (not yet released, but in use by ourselves), that provides scoreboards for streaming sport events.
Today it is expected, that there are nice animations for goals, etc. We are streaming using NDI, which requires a CVPixelBuffer for each frame.
We currently create these animations using CABasicAnimation, CAAnimation and CAKeyframeAnimation. In addition we use ScreenCaptureKit to generate the frames.
This works fine with 25/30 fps, as long as the window where our animations are performed in is visible. But this is not what it should be. We have a smaller window as main app window and control display performing the animations in reduced size, while the streaming animations need to be in HD format and later maybe in 4K.
When using an offscreen window, the animations are not calculated. We get 1 frame per second or so. So we actually have to connect an external display to the MacBook and open the large windows there. Ugly solution.
Do we use a completely wrong approach? Or is there a way to tell the macOS to perform the animations although it is an offscreen window?
If it cannot work that way, what is an alternative?
I have really enjoyed looking through the code and videos related to Metal 4. Currently, my interest is to update a ReSTIR Project and take advantage of more robust ways to refit acceleration Structures and more powerful ways to access resources.
I am working in Swift and have encountered a couple of puzzles:
What is the 'accepted' way to create a MTL4BufferRange to store indices and vertices?
How do I properly rewrite Swift code to build and compact an Acceleration Structure?
I do realize that this is all in Beta and will happily look through Code Samples this Fall. If other guidance is available earlier, that would be fabulous!
Thank you
The game physics work as expected using GTPK 2.0 using Crossover 24 or Whisky. However, using GPTK 2.1 with Crossover 25, the player and camera physics misbehave. See https://www.reddit.com/r/WWEGames/comments/1jx9mph/the_siamese_elbow/ and https://www.reddit.com/r/WWEGames/comments/1jx9ow4/camera_glitch/
Full video also linked in the Reddit post.
I have also submitted this bug via the feedback assistant.
Hi everyone,
I'm using the Vision framework’s ImageAestheticsScoresObservation class (https://developer.apple.com/documentation/vision/imageaestheticsscoresobservation).
I noticed that the overallScore returned sometimes gives negative values. Could someone confirm whether the expected range of the score is from -1.0 to 1.0?
The documentation doesn’t explicitly state the possible score range, so I’d appreciate any clarification or insights.
Thanks in advance!
I have noticed that the performance drop on SpriteKit-based projects running on iOS 26 is still ongoing
With iOS 26 back in Sep 2025 a framerate problem was introduced. My app was always running smoothly with 60fps even on very old devices suddenly started to stutter with 40fps - and lower on a rather normal iPhone 13.
This problem continued with BETA 26.1
The problem was fixed in 26.2.
But 26.3 brought the problem back and its still ongoing with 26.4 of yesterday
This is easily reproducible with a very simple example
//
// BareboneSpriteKitApp.swift
// BareboneSpriteKit
//
// Created by Bernd Beyreuther on 24.02.26.
//
import SwiftUI
import SpriteKit
@main
struct BareboneSpriteKitApp: App {
var body: some Scene {
WindowGroup {
BareboneSceneView()
}
}
}
final class BareboneScene: SKScene {
override func didMove(to view: SKView) {
size = view.bounds.size
scaleMode = .resizeFill
anchorPoint = CGPoint(x: 0.5, y: 0.5)
backgroundColor = .darkGray
let s = SKSpriteNode(color: .cyan, size: CGSize(width: 64, height: 64))
addChild(s)
let action = SKAction.rotate(byAngle: .pi, duration: 2)
s.run(.repeatForever(action))
let t = SKLabelNode(text: deviceInfoString())
t.fontSize = 15
t.position.y = -100
addChild(t)
}
}
struct BareboneSceneView: View {
var body: some View {
SpriteView(
scene: BareboneScene(),
debugOptions: [.showsFPS]
)
.ignoresSafeArea()
}
}
func deviceInfoString() -> String {
let os = ProcessInfo.processInfo.operatingSystemVersion
let osString = "iOS \(os.majorVersion).\(os.minorVersion).\(os.patchVersion)"
let model = UIDevice.current.model // "iPhone", "iPad"
let machine = {
var sysinfo = utsname()
uname(&sysinfo)
return withUnsafePointer(to: &sysinfo.machine) { ptr -> String in
ptr.withMemoryRebound(to: CChar.self, capacity: 1) { cptr in
String(cString: cptr)
}
}
}() // z.B. "iPhone15,2"
return "Model Identifier: \(model) (\(machine)), \(osString)"
}
I file a bugreport via Feedback Assistant FB22038921
The problem is no around for such a long time ! This is deeply concerning, because it questions if it is really feasable to continue to develop using Spritekit ?
Hi,
wanted to test if possible to use Mesa3D OGLon12+D3DMetal 2b3 to get GL>4.1 support on windows apps via D3D12Metal..
using simple wglgears.c app (similar glxgears) and running like:
GALLIUM_DRIVER=d3d12 wine64 wglgears64 -info
with overridden opengl32.dll using contents from:
https://github.com/pal1000/mesa-dist-win/releases/download/24.3.0-rc1/mesa3d-24.3.0-rc1-release-msvc.7z
I get:
[D3DMetal:LOG:5E53] Unsupported API: CreateCommandQueue1
caused by:
https://gitlab.freedesktop.org/mesa/mesa/-/commit/c022c9603d500b59ff5e6f93c8a214d1785ab20a
API:
https://learn.microsoft.com/en-us/windows/win32/api/d3d12/nf-d3d12-id3d12device9-createcommandqueue1
note setup is correct as using:
GALLIUM_DRIVER=llvmpipe wine64 wglgears64 -info
I get:
GL_RENDERER = llvmpipe (LLVM 19.1.3, 128 bits)
GL_VERSION = 4.5 (Compatibility Profile) Mesa 24.3.0-rc1 (git-85ba713d76)
GL_VENDOR = Mesa
GL_EXTENSIONS = GL_ARB_multisample GL_EXT_abgr GL_EXT_bgra GL_EXT_blend_color GL_EXT_blend_minmax GL_EXT_blend_subtract
r GL_EXT_texture.. etc..
I've coded a text-adventure game in SwiftUI. (My game has no graphics or sound effects.)
My app already supports keyboard navigation; I would like to add support for game controllers on iPhone. I can't figure out how to do it. I especially can't see any way to allow controller users to enter text in a TextField.
I've read https://developer.apple.com/documentation/gamecontroller/supporting-game-controllers and it's all about button events. There's no reference to SwiftUI at all in that documentation, or any input-method editing at all. The only mention of "keyboard" is about treating the keyboard itself as if it were a game controller providing button events.
How do I implement this?
So, I'm done with GPTK and decided to delete it. The only thing I installed was brew -v install apple/apple/game-porting-toolkit and the external libraries from the ditto command. Now, I tried to remove it, but even after
brew remove game-porting-toolkit
brew autoremove
all of the dependencies installed with brew are still there. The most obvious was game-porting-toolkit-compiler, but even after removing this there are so many libraries that are now orphaned and it's just impossible to manually identify those. Is there a way or is the easiest way to simply uninstall Homebrew completely and reinstall it again?
Hi,
I'm trying to add game center challenges and activities to an already live game, but they are not appearing in game for testing, GameCenter, or the Games app.
I know the game is setup with GameKit entitlements since this is a live game and it has working leaderboards and achievements.
I've updated to Tahoe beta 8, added a challenge and activity on app store connect, added that to a new distribution and added that distribution to 'Add for Review'
I'm using Unity and the Apple Unity plugin
Not sure what other steps I'm missing
Thanks
I am currently using RealityKit (perspective camera) to render a character in my swiftUI app.
The character has customization such as clothing items and hair and all objects are properly weighted to the rig.
The way the model is setup in Blender is like so: Groups of objects that will be swapped (ex: Shoes -> Shoes objects) and an armature. I then export it to usdc with all objects active. This is the resulting entity hierarchy, viewed in Reality Composer Pro:
My problem is that when I export with the Armature Modifier applied to the objects, so that animations get exported, the ModelComponent gets flattened to the armature and swapping entities is no longer as simple as removing the entity with the corresponding name.
What's the best practice here? Should animation be exported separately and then applied to the skeleton? If so, how is that achieved? I'm not really sure how to proceed here.
Hey I'm using the CIDepthBlurEffect Core Image Filter in my app. It seems to work ok but I get these errors in the console when calling the class.
CoreImage Metal library does not contain function for name: sparserendering_xhlrb_scan
CoreImage Metal library does not contain function for name: sparserendering_xhlrb_diffuse
CoreImage Metal library does not contain function for name: sparserendering_xhlrb_copy_back
CoreImage Metal library does not contain function for name: plain_or_sRGB_copy
Am I missing some sort of import to gain these Metal functions? I am using my own custom shaders but I assume you'd be able to use them along side the built in ones.
I mean…I want to use defaults rather than launching apps via open with the saved environment variables.
This is pretty easy on iOS and other platforms. So what about in macOS?