include/SDL3/SDL_metal.h

/*
  Simple DirectMedia Layer
  Copyright (C) 1997-2026 Sam Lantinga <slouken@libsdl.org>

  This software is provided 'as-is', without any express or implied
  warranty.  In no event will the authors be held liable for any damages
  arising from the use of this software.

  Permission is granted to anyone to use this software for any purpose,
  including commercial applications, and to alter it and redistribute it
  freely, subject to the following restrictions:

  1. The origin of this software must not be misrepresented; you must not
     claim that you wrote the original software. If you use this software
     in a product, an acknowledgment in the product documentation would be
     appreciated but is not required.
  2. Altered source versions must be plainly marked as such, and must not be
     misrepresented as being the original software.
  3. This notice may not be removed or altered from any source distribution.
*/

/**
 * # CategoryMetal
 *
 * Functions to creating Metal layers and views on SDL windows.
 *
 * This provides some platform-specific glue for Apple platforms. Most macOS
 * and iOS apps can use SDL without these functions, but this API they can be
 * useful for specific OS-level integration tasks.
 */

#ifndef SDL_metal_h_
#define SDL_metal_h_

#include <SDL3/SDL_video.h>

#include <SDL3/SDL_begin_code.h>
/* Set up for C function definitions, even when using C++ */
#ifdef __cplusplus
extern "C" {
#endif

/**
 * A handle to a CAMetalLayer-backed NSView (macOS) or UIView (iOS/tvOS).
 *
 * \since This datatype is available since SDL 3.2.0.
 */
typedef void *SDL_MetalView;

/**
 *  \name Metal support functions
 */
/* @{ */

/**
 * Create a CAMetalLayer-backed NSView/UIView and attach it to the specified
 * window.
 *
 * On macOS, this does *not* associate a MTLDevice with the CAMetalLayer on
 * its own. It is up to user code to do that.
 *
 * The returned handle can be casted directly to a NSView or UIView. To access
 * the backing CAMetalLayer, call SDL_Metal_GetLayer().
 *
 * \param window the window.
 * \returns handle NSView or UIView.
 *
 * \threadsafety This function should only be called on the main thread.
 *
 * \since This function is available since SDL 3.2.0.
 *
 * \sa SDL_Metal_DestroyView
 * \sa SDL_Metal_GetLayer
 */
extern SDL_DECLSPEC SDL_MetalView SDLCALL SDL_Metal_CreateView(SDL_Window *window);

/**
 * Destroy an existing SDL_MetalView object.
 *
 * This should be called before SDL_DestroyWindow, if SDL_Metal_CreateView was
 * called after SDL_CreateWindow.
 *
 * \param view the SDL_MetalView object.
 *
 * \threadsafety This function should only be called on the main thread.
 *
 * \since This function is available since SDL 3.2.0.
 *
 * \sa SDL_Metal_CreateView
 */
extern SDL_DECLSPEC void SDLCALL SDL_Metal_DestroyView(SDL_MetalView view);

/**
 * Get a pointer to the backing CAMetalLayer for the given view.
 *
 * \param view the SDL_MetalView object.
 * \returns a pointer.
 *
 * \threadsafety This function should only be called on the main thread.
 *
 * \since This function is available since SDL 3.2.0.
 */
extern SDL_DECLSPEC void * SDLCALL SDL_Metal_GetLayer(SDL_MetalView view);

/* @} *//* Metal support functions */

/* Ends C function definitions when using C++ */
#ifdef __cplusplus
}
#endif
#include <SDL3/SDL_close_code.h>

#endif /* SDL_metal_h_ */