Hi all,
A metal project of mine suddenly stopped working after upgrading to Xcode11 and iOS13. I found out that this is related to the SKRenderer class and its render(withViewport:commandBuffer:renderPassDescriptor:) method. I use metal to render a 3d environment and use SKRenderer to overlay a UI on top of that. Xcode does not crash or present any error, it just stops drawing/updating after a couple of frames (around 0.5 seconds in) and freezes my screen. This only happens when running the app through Xcode. If I run the app directly from my phone after, it runs just fine. However, this prevents me from using Xcode's debugging tools.
I tried to create a new clean project using SKRenderer and only one scene with one label, but it still freezes. I also tried removing SKRenderer from my rendering setup, this works but obviously I need my SpriteKit UI.
The code where it goes wrong is shown below (i removed all the clutter to only show the essentials).
public init(....) {
...
self.render = SKRenderer(device: OContext.device)
self.render.scene = aSKScene
}
open func draw(commandBuffer: MTLCommandBuffer) {
// Draw scene
let viewport = CGRect(origin: CGPoint.zero, size: self.size)
self.render.update(atTime: CACurrentMediaTime())
// FREEZES BELOW
self.render.render(withViewport: viewport, commandBuffer: commandBuffer, renderPassDescriptor: self.descriptor)
}When the app freezes and I click on pause within Xcode it shows me:
App > Thread 1 > 0 semaphore_wait_trap
libsystem_kernel.dylib`semaphore_wait_trap:
0x1a6442bf8 <+0>: mov x16, #-0x24
0x1a6442bfc <+4>: svc #0x80
-> 0x1a6442c00 <+8>: ret App > Thread 1 > 15 -[SKRenderer renderWithViewport:commandBuffer:renderPassDescriptor:]
SpriteKit`-[SKRenderer renderWithViewport:commandBuffer:renderPassDescriptor:]:
0x1bf1227f4 <+0>: pacibsp
0x1bf1227f8 <+4>: stp d11, d10, [sp, #-0x60]!
0x1bf1227fc <+8>: stp d9, d8, [sp, #0x10]
0x1bf122800 <+12>: stp x24, x23, [sp, #0x20]
0x1bf122804 <+16>: stp x22, x21, [sp, #0x30]
0x1bf122808 <+20>: stp x20, x19, [sp, #0x40]
0x1bf12280c <+24>: stp x29, x30, [sp, #0x50]
0x1bf122810 <+28>: add x29, sp, #0x50 ; =0x50
0x1bf122814 <+32>: mov x20, x3
0x1bf122818 <+36>: mov.16b v8, v3
0x1bf12281c <+40>: mov.16b v9, v2
0x1bf122820 <+44>: mov.16b v10, v1
0x1bf122824 <+48>: mov.16b v11, v0
0x1bf122828 <+52>: mov x22, x0
0x1bf12282c <+56>: mov x0, x2
0x1bf122830 <+60>: bl 0x1b8139128
0x1bf122834 <+64>: mov x19, x0
0x1bf122838 <+68>: mov x0, x20
0x1bf12283c <+72>: bl 0x1b8139128
0x1bf122840 <+76>: mov x20, x0
0x1bf122844 <+80>: adrp x8, 126727
0x1bf122848 <+84>: add x1, x8, #0x9c2 ; =0x9c2
0x1bf12284c <+88>: mov x0, x19
0x1bf122850 <+92>: bl 0x1b81390b8
0x1bf122854 <+96>: mov x29, x29
0x1bf122858 <+100>: bl 0x1b8139158
0x1bf12285c <+104>: mov x21, x0
0x1bf122860 <+108>: adrp x8, 126734
0x1bf122864 <+112>: add x1, x8, #0x3c1 ; =0x3c1
0x1bf122868 <+116>: mov x0, x19
0x1bf12286c <+120>: mov x2, x20
0x1bf122870 <+124>: bl 0x1b81390b8
0x1bf122874 <+128>: mov x29, x29
0x1bf122878 <+132>: bl 0x1b8139158
0x1bf12287c <+136>: mov x23, x0
0x1bf122880 <+140>: adrp x8, 126725
0x1bf122884 <+144>: add x1, x8, #0x696 ; =0x696
0x1bf122888 <+148>: adrp x2, 163830
0x1bf12288c <+152>: add x2, x2, #0x6e0 ; =0x6e0
0x1bf122890 <+156>: bl 0x1b81390b8
0x1bf122894 <+160>: adrp x8, 129605
0x1bf122898 <+164>: add x1, x8, #0xbb7 ; =0xbb7
0x1bf12289c <+168>: mov.16b v0, v11
0x1bf1228a0 <+172>: mov.16b v1, v10
0x1bf1228a4 <+176>: mov.16b v2, v9
0x1bf1228a8 <+180>: mov.16b v3, v8
0x1bf1228ac <+184>: mov x0, x22
0x1bf1228b0 <+188>: mov x2, x23
0x1bf1228b4 <+192>: mov x3, x20
0x1bf1228b8 <+196>: mov x4, x21
0x1bf1228bc <+200>: bl 0x1b81390b8
-> 0x1bf1228c0 <+204>: adrp x8, 126721
0x1bf1228c4 <+208>: add x1, x8, #0x3a5 ; =0x3a5
0x1bf1228c8 <+212>: mov x0, x23
0x1bf1228cc <+216>: bl 0x1b81390b8
0x1bf1228d0 <+220>: mov x0, x23
0x1bf1228d4 <+224>: bl 0x1b8139118
0x1bf1228d8 <+228>: mov x0, x21
0x1bf1228dc <+232>: bl 0x1b8139118
0x1bf1228e0 <+236>: mov x0, x20
0x1bf1228e4 <+240>: bl 0x1b8139118
0x1bf1228e8 <+244>: mov x0, x19
0x1bf1228ec <+248>: ldp x29, x30, [sp, #0x50]
0x1bf1228f0 <+252>: ldp x20, x19, [sp, #0x40]
0x1bf1228f4 <+256>: ldp x22, x21, [sp, #0x30]
0x1bf1228f8 <+260>: ldp x24, x23, [sp, #0x20]
0x1bf1228fc <+264>: ldp d9, d8, [sp, #0x10]
0x1bf122900 <+268>: ldp d11, d10, [sp], #0x60
0x1bf122904 <+272>: autibsp
0x1bf122908 <+276>: b 0x1b8139118
0x1bf12290c <+280>: mov x22, x0
0x1bf122910 <+284>: b 0x1bf122928 ; <+308>
0x1bf122914 <+288>: mov x22, x0
0x1bf122918 <+292>: b 0x1bf122930 ; <+316>
0x1bf12291c <+296>: mov x22, x0
0x1bf122920 <+300>: mov x0, x23
0x1bf122924 <+304>: bl 0x1b8139118
0x1bf122928 <+308>: mov x0, x21
0x1bf12292c <+312>: bl 0x1b8139118
0x1bf122930 <+316>: mov x0, x20
0x1bf122934 <+320>: bl 0x1b8139118
0x1bf122938 <+324>: mov x0, x19
0x1bf12293c <+328>: bl 0x1b8139118
0x1bf122940 <+332>: mov x0, x22
0x1bf122944 <+336>: bl 0x1b8138888
0x1bf122948 <+340>: brk #0x1Next step in the thread shows the render method I posted above.
Anyone else having this issue? What could be the problem?
