Working on the project using Metal. Instead of using MTKView, I use a customized View inherited from NSView and use CAMetalLayer as backing layer:
- (CALayer*)makeBackingLayer
{
return [CAMetalLayer layer];
}
- (instancetype)initWithFrame:(NSRect)frameRect
{
self = [super initWithFrame:frameRect];
if ( self != nullptr )
{
[self setWantsLayer:YES];
[self setLayerContentsRedrawPolicy:NSViewLayerContentsRedrawDuringViewResize];
}
return self;
}
When first showing, the rendering is OK. But after resizing the View, the rendering is weird. After debugging, I find that, after resizing, the bounds of NSView and CAMetalLayer are already updated, but the MTLTexture's size is still the old one:
(lldb) po m_metalLayer # the same address for m_metalLayer between resizing.
<CAMetalLayer:0x610000c2f620; position = CGPoint (0 0); bounds = CGRect (0 0; 1126 636); delegate = <MyMetalView: 0x610000192bd0>; contents = <CAImageQueue 0x610000190a80>; opaque = YES; masksToBounds = YES; allowsDisplayCompositing = YES; contentsScale = 2; backgroundFilters = (
); filters = (
); shadowColor = (null); anchorPoint = CGPoint (0 0); NS_view = <MyMetalView: 0x610000192bd0>>
(lldb) po NSStringFromSize([m_metalLayer drawableSize]) #the drawableSize is not equal to bounds * contentsScale.
{2984, 1604}
(lldb) po [[m_metalLayer nextDrawable] texture]
<BronzeMtlTexture: 0x14a074280>
label = Drawable
textureType = MTLTextureType2D
pixelFormat = MTLPixelFormatBGRA8Unorm
width = 2984
height = 1604
depth = 1
arrayLength = 1
mipmapLevelCount = 1
sampleCount = 1
cpuCacheMode = MTLCPUCacheModeDefaultCache
storageMode = MTLStorageModeManaged
resourceOptions = MTLResourceCPUCacheModeDefaultCache MTLResourceStorageModeManaged
usage = MTLTextureUsageShaderRead MTLTextureUsageShaderWrite MTLTextureUsageRenderTarget MTLTextureUsagePixelFormatView
framebufferOnly = 1
purgeableState = MTLPurgeableStateNonVolatile
parentTexture = <null>
parentRelativeLevel = 0
parentRelativeSlice = 0
buffer = <null>
bufferOffset = 0
bufferBytesPerRow = 0
iosurface = 0x61c000003580
iosurfacePlane = 0
label = Drawable
Did I miss something here?
And For MTKView class, it has autoResizeDrawable property ( https://developer.apple.com/documentation/metalkit/mtkview/1535938-autoresizedrawable?language=objc) How can I achieve the same result for normal NSview with MTKView's autoResizeDrawable = YES?
Thanks.
