217377 2020-10-06 04:47:43 -0700 Implement ANGLE version of WebGL layer snapshot copyImageSnapshotWithColorSpace 2021-09-01 22:47:31 -0700 1 1 1 Unclassified WebKit WebGL WebKit Local Build Mac Unspecified RESOLVED FIXED InRadar P2 Normal --- 198948 1 kkinnunen kkinnunen dino jdarpinian kbr simon.fraser thorton webkit-bug-importer oldest_to_newest 1695096 0 kkinnunen 2020-10-06 04:47:43 -0700 To understand: Should the function snapshot the back buffer or the front buffer? Old CGL implementation (not sure if this is correct implementation) #if USE(OPENGL) CGLContextObj cglContext = static_cast<CGLContextObj>(_context->platformGraphicsContextGL()); CGLSetCurrentContext(cglContext); RetainPtr<CGColorSpaceRef> imageColorSpace = colorSpace; if (!imageColorSpace) imageColorSpace = WebCore::sRGBColorSpaceRef(); CGRect layerBounds = CGRectIntegral([self bounds]); size_t width = layerBounds.size.width * _devicePixelRatio; size_t height = layerBounds.size.height * _devicePixelRatio; size_t rowBytes = (width * 4 + 15) & ~15; size_t dataSize = rowBytes * height; void* data = fastMalloc(dataSize); if (!data) return nullptr; glPixelStorei(GL_PACK_ROW_LENGTH, rowBytes / 4); glReadPixels(0, 0, width, height, GL_BGRA, GL_UNSIGNED_INT_8_8_8_8_REV, data); WebCore::verifyImageBufferIsBigEnough((uint8_t*)data, dataSize); CGDataProviderRef provider = CGDataProviderCreateWithData(0, data, dataSize, freeData); CGImageRef image = CGImageCreate(width, height, 8, 32, rowBytes, imageColorSpace.get(), kCGImageAlphaPremultipliedFirst | kCGBitmapByteOrder32Host, provider, 0, true, kCGRenderingIntentDefault); CGDataProviderRelease(provider); return image; #else 1697224 1 webkit-bug-importer 2020-10-13 04:48:16 -0700 <rdar://problem/70248151> 1701612 2 kbr 2020-10-26 14:05:09 -0700 Which code calls this method? The old implementation used the front buffer and perhaps that's the correct semantic, but it's not clear because there doesn't seem to be any documentation for it. 1701778 3 kkinnunen 2020-10-26 23:33:02 -0700 As per my understanding, the old implementation used the back buffer, not the front buffer. This is on the grounds that there's no bind of any kind, so it expects to read what is bound. The front buffer is not bound ever. In fact, the old code did not have any concept of front buffer conceptually "inside OpenGL", so it can not be read by that read pixels. Front buffer it a CA layer holding a IOSurface. The only way it can be reading front buffer if it was, back in the day before prepareForDisplay, called during CA commit but before buffer swap. E.g. it would read the back buffer just before it became front buffer. However, even in this case it will either have read wrong frame buffers if client had bound something or alternatively left gl state wrong (by a bind that is not seen in the code). I couldn't find the call site, so I'd assume it is either dead code or CALayer Obj-C vfunc override which I'm not that familiar with at the moment. 1702460 4 kbr 2020-10-28 12:56:46 -0700 Sorry - I must have been tired - you're right, and I meant that it looked like it was snapshotting the back buffer. 1702461 5 kbr 2020-10-28 12:57:21 -0700 If it looks like this function's unused then perhaps the best thing to do is to remove it along with the old implementations. 1788856 6 kkinnunen 2021-08-31 03:44:16 -0700 Function introduced in trunk@50067 2009-10-26 Simon Fraser <simon.fraser@apple.com> Reviewed by Sam Weinig. <rdar://problem/6988966> Hardware layers do not show up in page snapshots * WebView/WebHTMLViewPrivate.h: * WebView/WebHTMLView.mm: (-[WebHTMLView _compositingLayersHostingView]): Add a private method that returns the NSView used to host compositing layers. * platform/graphics/mac/Canvas3DLayer.h: * platform/graphics/mac/Canvas3DLayer.mm: (-[Canvas3DLayer copyImageSnapshotWithColorSpace:]): Add a method that gets called when snapshotting Canvas3DLayers for page snapshots, that allows the layer to return a CGImageRef of its contents. Unclear if it's still used. 1788871 7 436876 kkinnunen 2021-08-31 05:01:29 -0700 Created attachment 436876 Patch 1789602 8 ews-feeder 2021-09-01 22:47:29 -0700 Committed r281909 (241221@main): <https://commits.webkit.org/241221@main> All reviewed patches have been landed. Closing bug and clearing flags on attachment 436876. 436876 2021-08-31 05:01:29 -0700 2021-09-01 22:47:30 -0700 Patch bug-217377-20210831150127.patch text/plain 2290 kkinnunen U3VidmVyc2lvbiBSZXZpc2lvbjogMjgxNzUzCmRpZmYgLS1naXQgYS9Tb3VyY2UvV2ViQ29yZS9D aGFuZ2VMb2cgYi9Tb3VyY2UvV2ViQ29yZS9DaGFuZ2VMb2cKaW5kZXggMjM5MDU1ZGE1ZjU1Yzhh Y2M0MTVkMDVkNzdmNjE5Y2E1MWNkNTJiNi4uZWY2Y2NjMjdmYTFlZjY2OWQxYTFiZTllYzg1NTc2 MDdkMTgzNTE0NiAxMDA2NDQKLS0tIGEvU291cmNlL1dlYkNvcmUvQ2hhbmdlTG9nCisrKyBiL1Nv dXJjZS9XZWJDb3JlL0NoYW5nZUxvZwpAQCAtMSwzICsxLDE2IEBACisyMDIxLTA4LTMxICBLaW1t byBLaW5udW5lbiAgPGtraW5udW5lbkBhcHBsZS5jb20+CisKKyAgICAgICAgSW1wbGVtZW50IEFO R0xFIHZlcnNpb24gb2YgV2ViR0wgbGF5ZXIgc25hcHNob3QgY29weUltYWdlU25hcHNob3RXaXRo Q29sb3JTcGFjZQorICAgICAgICBodHRwczovL2J1Z3Mud2Via2l0Lm9yZy9zaG93X2J1Zy5jZ2k/ aWQ9MjE3Mzc3CisgICAgICAgIDxyZGFyOi8vcHJvYmxlbS83MDI0ODE1MT4KKworICAgICAgICBS ZXZpZXdlZCBieSBOT0JPRFkgKE9PUFMhKS4KKworICAgICAgICBSZW1vdmUgdGhlIGZ1bmN0aW9u LiBUaGUgc25hcHNob3RzIGdvIHRocm91Z2ggdGhlIHBhaW50IGNvZGVwYXRoIG5vdy4KKworICAg ICAgICAqIHBsYXRmb3JtL2dyYXBoaWNzL2NvY29hL1dlYkdMTGF5ZXIuaDoKKyAgICAgICAgKiBw bGF0Zm9ybS9ncmFwaGljcy9jb2NvYS9XZWJHTExheWVyLm1tOgorCiAyMDIxLTA4LTI5ICBBbGFu IEJ1anRhcyAgPHphbGFuQGFwcGxlLmNvbT4KIAogICAgICAgICBbTEZDXVtJRkNdIE1vdmUgImxp bmUgbmVlZHMgaW50ZWdyYWwgc25hcHBpbmciIGNvbXB1dGluZyB0byBJRkMgZnJvbSB0aGUgaW50 ZWdyYXRpb24gbGF5ZXIKZGlmZiAtLWdpdCBhL1NvdXJjZS9XZWJDb3JlL3BsYXRmb3JtL2dyYXBo aWNzL2NvY29hL1dlYkdMTGF5ZXIuaCBiL1NvdXJjZS9XZWJDb3JlL3BsYXRmb3JtL2dyYXBoaWNz L2NvY29hL1dlYkdMTGF5ZXIuaAppbmRleCA3ZmU4OGEyZmY0Y2UwZjU1OWQ1OWRjMWNkOTUyYTNh N2VhODgwOTYyLi4xNDRjNWE0MjRhN2EzZTQ2MzRiODY0YjNiZjIwNzAxNzI2NjI0NTVkIDEwMDY0 NAotLS0gYS9Tb3VyY2UvV2ViQ29yZS9wbGF0Zm9ybS9ncmFwaGljcy9jb2NvYS9XZWJHTExheWVy LmgKKysrIGIvU291cmNlL1dlYkNvcmUvcGxhdGZvcm0vZ3JhcGhpY3MvY29jb2EvV2ViR0xMYXll ci5oCkBAIC0zNiw4ICszNiw2IEBAIEFMTE9XX0RFUFJFQ0FURURfREVDTEFSQVRJT05TX0JFR0lO CiAKIC0gKGlkKWluaXRXaXRoRGV2aWNlUGl4ZWxSYXRpbzooZmxvYXQpZGV2aWNlUGl4ZWxSYXRp byBjb250ZW50c09wYXF1ZTooYm9vbCljb250ZW50c09wYXF1ZTsKIAotLSAoQ0dJbWFnZVJlZilj b3B5SW1hZ2VTbmFwc2hvdFdpdGhDb2xvclNwYWNlOihDR0NvbG9yU3BhY2VSZWYpY29sb3JTcGFj ZTsKLQogLSAoV2ViQ29yZTo6R3JhcGhpY3NDb250ZXh0R0xJT1N1cmZhY2VTd2FwQ2hhaW4mKSBz d2FwQ2hhaW47CiAKIEBlbmQKZGlmZiAtLWdpdCBhL1NvdXJjZS9XZWJDb3JlL3BsYXRmb3JtL2dy YXBoaWNzL2NvY29hL1dlYkdMTGF5ZXIubW0gYi9Tb3VyY2UvV2ViQ29yZS9wbGF0Zm9ybS9ncmFw aGljcy9jb2NvYS9XZWJHTExheWVyLm1tCmluZGV4IGVhZTk2Zjc2YjMwMmY1ZjYwMzk4ZjFiODBl OGQ4NWZlODZiYWQ2ZTguLmE2ZTljZmY1MDNhM2QyZmI2NjVjYjcwMDM0NTFhZjUxZGY0Njc4OTMg MTAwNjQ0Ci0tLSBhL1NvdXJjZS9XZWJDb3JlL3BsYXRmb3JtL2dyYXBoaWNzL2NvY29hL1dlYkdM TGF5ZXIubW0KKysrIGIvU291cmNlL1dlYkNvcmUvcGxhdGZvcm0vZ3JhcGhpY3MvY29jb2EvV2Vi R0xMYXllci5tbQpAQCAtNzUsMTMgKzc1LDYgQEAgcHJpdmF0ZToKICAgICBbc3VwZXIgc2V0QW5j aG9yUG9pbnQ6Q0dQb2ludE1ha2UocC54LCAxLjAgLSBwLnkpXTsKIH0KIAotLSAoQ0dJbWFnZVJl Ziljb3B5SW1hZ2VTbmFwc2hvdFdpdGhDb2xvclNwYWNlOihDR0NvbG9yU3BhY2VSZWYpY29sb3JT cGFjZQotewotICAgIC8vIEZJWE1FOiBpbXBsZW1lbnQuIGh0dHBzOi8vYnVncy53ZWJraXQub3Jn L3Nob3dfYnVnLmNnaT9pZD0yMTczNzcKLSAgICAvLyBXaGVuIGltcGxlbWVudGluZywgcmVtZW1i ZXIgdG8gdXNlIHNlbGYuY29udGVudHNTY2FsZS4KLSAgICBVTlVTRURfUEFSQU0oY29sb3JTcGFj ZSk7Ci0gICAgcmV0dXJuIG51bGxwdHI7Ci19CiAtIChXZWJDb3JlOjpHcmFwaGljc0NvbnRleHRH TElPU3VyZmFjZVN3YXBDaGFpbiYpIHN3YXBDaGFpbgogewogICAgIHJldHVybiBfc3dhcENoYWlu LnZhbHVlKCk7Cg==