I think if your buffer is less than 4k its recommended to use setVertexBytes, the question I have is can I keep hammering on setVertexBytes as the primary method to issue multiple draw calls within a render buffer and rely on Metal to figure out how to orphan and replace the target buffer? A lot of the primitives I am drawing are less than 4k and the process of wiring down larger segments of memory for individual buffers for each draw primitive call seems to be a negative. And it's just simpler to copy, submit and forget about buffer synchronization.

I would like to avoid the middle man and call Objective C directly from C Currently I do this This is called from a dispatch table in a pure C file _ctx->mt_render_funcs.mtlEnd(_ctx); Which calls this routine in a obj c file .m void mtlEnd(MTRenderContext mt_ctx) { // Call the Objective-C method using Objective-C syntax [(__bridge id) mt_ctx->mt_render_funcs.mtlObj mtlEnd]; } Which ends up here... in ObjC #pragma mark mtlEnd (void)mtlEnd { // vertex buffer size_t size; size = sizeof(Vertex4ColorNormalTex) * _ctx->vert_eng.current_vertex; [_currentRenderEncoder setVertexBytes:_ctx->vert_eng.vertices length: size atIndex: VertexInputIndexVertices]; [_currentRenderEncoder drawPrimitives:(MTLPrimitiveType)_ctx->vert_eng.prim_type vertexStart:0 vertexCount:_ctx->vert_eng.current_vertex]; } It would simplify this to get rid of one call and call ObjC directly. The other idea is I want to use GCD and put a lock / unlock on the call from C to ensure thread safety so I can use GCD to dispatch a thread to do the ObjC routines. I want to stick with C as the foundation so it can be used directly from C or a FFI interface from other languages. But Metal works well in ObjC and I would prefer to use that. Thanks ahead of time.

I get warnings like this on each project I build while debugging.. Internal inconsistency in menus - menu <NSMenu: 0x8b4b49ec0> Title: Help Supermenu: 0x8b4b49f80 (Main Menu), autoenable: YES Previous menu: 0x0 (None) Next menu: 0x0 (None) Items: ( "<NSMenuItem: 0x8b5771720 Metal4C Help, ke='Command-?'>" ) believes it has <NSMenu: 0x8b4b49f80> Title: Main Menu Supermenu: 0x0 (None), autoenable: YES Previous menu: 0x0 (None) Next menu: 0x0 (None) Items: ( ) as a supermenu, but the supermenu does not seem to have any item with that submenu What am I doing wrong? I get these errors even if I create a default app with no code?

I have a Xcode project with two apps that have a separate MainMenu.nib file. Both are different apps with different source trees.. Why am I seeing resources in interface builder from one app in another? I am a bit old school and using the AppDelegate rather than view controllers to capture events... but that should work fine Thanks ahead of time.

I have an odd bug, if I use initWithFrame as the init routine for NSView subclass that uses layers I don't see this bug. But if I embedded this view into a storyboard with a .nib file and use initWithCoder, I need to return true on (BOOL) contentsAreFlipped From the NSView subclass If I don't the CALayer actually renders from 0,0 from the view upwards and off the window. The frame sizes for the NSView and the CALayer are good.. when I see them in updateLayer. Obviously I have a fix.. but I would like to understand why.

I wrote my own framework and it uses some OpenGL calls, I have my own direct replacements for these calls. But Xcode complains when I try to integrate these calls into a NSApp that all of these calls are deprecated. It must be in some module that Appkit or Cocoa uses to include all the headers as I went through and eliminated all potential references. I could just encapsulate all of this in a separate C or C++ file, but I would rather write it all in Obj-C. I know it's just a warning, but I like to treat warnings as errors to catch as many bugs as possible.

I am building a framework and an app, the framework is a dependent on the app so that works.. But within the app I can't use #import <OpenGL_4_6/OpenGL_4_6.h> But I have to use #import "OpenGL_4_6/OpenGL_4_6.h" I can see the framework being built its in a directory that I can't seem to express with the $ macros for Xcode Library/Developer/Xcode/DerivedData/MGL-bpbwpidwnbulrxgcndprcdmfrosb/Build/Products/Debug I tried to set my framework search path to this.. but to no avail.

I have poked around the web looking for a good example to do this and I haven't found a working example. I need to connect to a USB Device, its multiple ports and supports what looks to be a root port and 4 other ports I am no expert in USB but I do know how to write a kext and client drivers, but thats really not the way to solve this. I need to display the serialized output from these USB ports for a development board. I would rather do this on my Mac than have to cobble up a Linux machine and mess around with Linux. Here is the output from ioreg MCHP-Debug@03100000 <class IOUSBHostDevice, id 0x105f6fdc2, registered, matched, active, busy 0 (20 ms), retain 27> MCHP-Debug@0 <class IOUSBHostInterface, id 0x105f6fdc8, registered, matched, active, busy 0 (13 ms), retain 5> +-o MCHP-Debug@0 <class IOUSBHostInterface, id 0x105f6fdc8, registered, matched, active, busy 0 (13 ms), retain 5> +-o MCHP-Debug@1 <class IOUSBHostInterface, id 0x105f6fdc9, registered, matched, active, busy 0 (11 ms), retain 5> +-o MCHP-Debug@2 <class IOUSBHostInterface, id 0x105f6fdcb, registered, matched, active, busy 0 (9 ms), retain 5> | | | | | +-o MCHP-Debug@3 <class IOUSBHostInterface, id 0x105f6fdcc, registered, matched, active, busy 0 (7 ms), retain 5> I have been able to open a inservice to the device at the top level, but I get an error when I use. usbHostInterface = [[IOUSBHostInterface alloc] initWithIOService:usbDevice options: IOUSBHostObjectInitOptionsNone queue: queue error: &error interestHandler: handler]; Error:Failed to create IOUSBHostInterface. with reason: Unable to obtain configuration descriptor. Assertion failed: (usbHostInterface), function main, file main.m, line 87. I started using DeviceKit but I received signing errors and I shouldn't have to go down that path just to dump data from a USB port? Any suggestions would be great, most of the Apple documentation on USB ports is like 20 years old and the new stuff pushes you towards DeviceKit.