src/video/cocoa/SDL_cocoaopengl.m
author Ryan C. Gordon <icculus@icculus.org>
Sat, 01 Mar 2014 21:33:48 -0500
changeset 8278 e60a7bb2b80b
parent 8276 9bd65b58278e
child 8601 4c04c7785cba
permissions -rw-r--r--
Dynamically load glGetString(), to avoid direct dependency on OpenGL.
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/*
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  Simple DirectMedia Layer
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  Copyright (C) 1997-2014 Sam Lantinga <slouken@libsdl.org>
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  This software is provided 'as-is', without any express or implied
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  warranty.  In no event will the authors be held liable for any damages
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  arising from the use of this software.
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  Permission is granted to anyone to use this software for any purpose,
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  including commercial applications, and to alter it and redistribute it
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  freely, subject to the following restrictions:
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  1. The origin of this software must not be misrepresented; you must not
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     claim that you wrote the original software. If you use this software
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     in a product, an acknowledgment in the product documentation would be
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     appreciated but is not required.
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  2. Altered source versions must be plainly marked as such, and must not be
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     misrepresented as being the original software.
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  3. This notice may not be removed or altered from any source distribution.
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*/
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#include "../../SDL_internal.h"
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/* NSOpenGL implementation of SDL OpenGL support */
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#if SDL_VIDEO_OPENGL_CGL
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#include "SDL_cocoavideo.h"
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#include "SDL_cocoaopengl.h"
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#include <OpenGL/CGLTypes.h>
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#include <OpenGL/OpenGL.h>
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#include <OpenGL/CGLRenderers.h>
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#include "SDL_loadso.h"
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#include "SDL_opengl.h"
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#define DEFAULT_OPENGL  "/System/Library/Frameworks/OpenGL.framework/Libraries/libGL.dylib"
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#ifndef NSOpenGLPFAOpenGLProfile
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#define NSOpenGLPFAOpenGLProfile 99
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#endif
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#ifndef NSOpenGLProfileVersionLegacy
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#define NSOpenGLProfileVersionLegacy 0x1000
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#endif
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#ifndef NSOpenGLProfileVersion3_2Core
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#define NSOpenGLProfileVersion3_2Core 0x3200
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#endif
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@implementation SDLOpenGLContext : NSOpenGLContext
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- (id)initWithFormat:(NSOpenGLPixelFormat *)format
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        shareContext:(NSOpenGLContext *)share
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{
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    self = [super initWithFormat:format shareContext:share];
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    if (self) {
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        SDL_AtomicSet(&self->dirty, 0);
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        self->window = NULL;
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    }
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    return self;
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}
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- (void)scheduleUpdate
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{
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    SDL_AtomicAdd(&self->dirty, 1);
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}
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/* This should only be called on the thread on which a user is using the context. */
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- (void)updateIfNeeded
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{
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    int value = SDL_AtomicSet(&self->dirty, 0);
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    if (value > 0) {
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        /* We call the real underlying update here, since -[SDLOpenGLContext update] just calls us. */
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        [super update];
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    }
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}
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/* This should only be called on the thread on which a user is using the context. */
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- (void)update
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{
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    /* This ensures that regular 'update' calls clear the atomic dirty flag. */
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    [self scheduleUpdate];
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    [self updateIfNeeded];
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}
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/* Updates the drawable for the contexts and manages related state. */
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- (void)setWindow:(SDL_Window *)newWindow
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{
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    if (self->window) {
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        SDL_WindowData *oldwindowdata = (SDL_WindowData *)self->window->driverdata;
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        /* Make sure to remove us from the old window's context list, or we'll get scheduled updates from it too. */
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        NSMutableArray *contexts = oldwindowdata->nscontexts;
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        @synchronized (contexts) {
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            [contexts removeObject:self];
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        }
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    }
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    self->window = newWindow;
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    if (newWindow) {
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        SDL_WindowData *windowdata = (SDL_WindowData *)newWindow->driverdata;
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        /* Now sign up for scheduled updates for the new window. */
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        NSMutableArray *contexts = windowdata->nscontexts;
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        @synchronized (contexts) {
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            [contexts addObject:self];
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        }
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        if ([self view] != [windowdata->nswindow contentView]) {
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            [self setView:[windowdata->nswindow contentView]];
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            if (self == [NSOpenGLContext currentContext]) {
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                [self update];
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            } else {
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                [self scheduleUpdate];
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            }
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        }
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    } else {
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        [self clearDrawable];
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        if (self == [NSOpenGLContext currentContext]) {
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            [self update];
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        } else {
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            [self scheduleUpdate];
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        }
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    }
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}
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@end
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int
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Cocoa_GL_LoadLibrary(_THIS, const char *path)
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{
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    /* Load the OpenGL library */
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    if (path == NULL) {
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        path = SDL_getenv("SDL_OPENGL_LIBRARY");
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    }
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    if (path == NULL) {
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        path = DEFAULT_OPENGL;
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    }
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    _this->gl_config.dll_handle = SDL_LoadObject(path);
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    if (!_this->gl_config.dll_handle) {
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        return -1;
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    }
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    SDL_strlcpy(_this->gl_config.driver_path, path,
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                SDL_arraysize(_this->gl_config.driver_path));
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    return 0;
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}
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void *
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Cocoa_GL_GetProcAddress(_THIS, const char *proc)
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{
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    return SDL_LoadFunction(_this->gl_config.dll_handle, proc);
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}
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void
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Cocoa_GL_UnloadLibrary(_THIS)
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{
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    SDL_UnloadObject(_this->gl_config.dll_handle);
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    _this->gl_config.dll_handle = NULL;
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}
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SDL_GLContext
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Cocoa_GL_CreateContext(_THIS, SDL_Window * window)
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{
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    SDL_VideoData *data = (SDL_VideoData *) _this->driverdata;
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    const GLubyte *(APIENTRY * glGetStringFunc)(GLenum) = NULL;
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    NSAutoreleasePool *pool;
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    SDL_VideoDisplay *display = SDL_GetDisplayForWindow(window);
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    SDL_DisplayData *displaydata = (SDL_DisplayData *)display->driverdata;
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    NSOpenGLPixelFormatAttribute attr[32];
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    NSOpenGLPixelFormat *fmt;
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    SDLOpenGLContext *context;
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    NSOpenGLContext *share_context = nil;
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    int i = 0;
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    const char *glversion;
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    int glversion_major;
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    int glversion_minor;
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    if (_this->gl_config.profile_mask == SDL_GL_CONTEXT_PROFILE_ES) {
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        SDL_SetError ("OpenGL ES is not supported on this platform");
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        return NULL;
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    }
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    if ((_this->gl_config.profile_mask == SDL_GL_CONTEXT_PROFILE_CORE) && (data->osversion < 0x1070)) {
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        SDL_SetError ("OpenGL Core Profile is not supported on this platform version");
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        return NULL;
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    }
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    pool = [[NSAutoreleasePool alloc] init];
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    /* specify a profile if we're on Lion (10.7) or later. */
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    if (data->osversion >= 0x1070) {
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        NSOpenGLPixelFormatAttribute profile = NSOpenGLProfileVersionLegacy;
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        if (_this->gl_config.profile_mask == SDL_GL_CONTEXT_PROFILE_CORE) {
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            profile = NSOpenGLProfileVersion3_2Core;
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        }
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        attr[i++] = NSOpenGLPFAOpenGLProfile;
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        attr[i++] = profile;
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    }
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    attr[i++] = NSOpenGLPFAColorSize;
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    attr[i++] = SDL_BYTESPERPIXEL(display->current_mode.format)*8;
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    attr[i++] = NSOpenGLPFADepthSize;
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    attr[i++] = _this->gl_config.depth_size;
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    if (_this->gl_config.double_buffer) {
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        attr[i++] = NSOpenGLPFADoubleBuffer;
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    }
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    if (_this->gl_config.stereo) {
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        attr[i++] = NSOpenGLPFAStereo;
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    }
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    if (_this->gl_config.stencil_size) {
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        attr[i++] = NSOpenGLPFAStencilSize;
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        attr[i++] = _this->gl_config.stencil_size;
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    }
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    if ((_this->gl_config.accum_red_size +
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         _this->gl_config.accum_green_size +
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         _this->gl_config.accum_blue_size +
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         _this->gl_config.accum_alpha_size) > 0) {
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        attr[i++] = NSOpenGLPFAAccumSize;
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        attr[i++] = _this->gl_config.accum_red_size + _this->gl_config.accum_green_size + _this->gl_config.accum_blue_size + _this->gl_config.accum_alpha_size;
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    }
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    if (_this->gl_config.multisamplebuffers) {
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        attr[i++] = NSOpenGLPFASampleBuffers;
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        attr[i++] = _this->gl_config.multisamplebuffers;
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    }
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    if (_this->gl_config.multisamplesamples) {
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        attr[i++] = NSOpenGLPFASamples;
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        attr[i++] = _this->gl_config.multisamplesamples;
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        attr[i++] = NSOpenGLPFANoRecovery;
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    }
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    if (_this->gl_config.accelerated >= 0) {
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        if (_this->gl_config.accelerated) {
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            attr[i++] = NSOpenGLPFAAccelerated;
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        } else {
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            attr[i++] = NSOpenGLPFARendererID;
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            attr[i++] = kCGLRendererGenericFloatID;
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        }
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    }
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    attr[i++] = NSOpenGLPFAScreenMask;
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    attr[i++] = CGDisplayIDToOpenGLDisplayMask(displaydata->display);
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    attr[i] = 0;
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    fmt = [[NSOpenGLPixelFormat alloc] initWithAttributes:attr];
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    if (fmt == nil) {
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        SDL_SetError ("Failed creating OpenGL pixel format");
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        [pool release];
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        return NULL;
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    }
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    if (_this->gl_config.share_with_current_context) {
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        share_context = (NSOpenGLContext*)SDL_GL_GetCurrentContext();
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    }
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    context = [[SDLOpenGLContext alloc] initWithFormat:fmt shareContext:share_context];
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    [fmt release];
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    if (context == nil) {
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        SDL_SetError ("Failed creating OpenGL context");
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        [pool release];
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        return NULL;
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    }
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    [pool release];
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    if ( Cocoa_GL_MakeCurrent(_this, window, context) < 0 ) {
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        Cocoa_GL_DeleteContext(_this, context);
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        SDL_SetError ("Failed making OpenGL context current");
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        return NULL;
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    }
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    glGetStringFunc = (const GLubyte *(APIENTRY *)(GLenum)) SDL_GL_GetProcAddress("glGetString");
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    if (!glGetStringFunc) {
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        Cocoa_GL_DeleteContext(_this, context);
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        SDL_SetError ("Failed getting OpenGL glGetString entry point");
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        return NULL;
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    }
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    glversion = (const char *)glGetStringFunc(GL_VERSION);
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    if (glversion == NULL) {
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        Cocoa_GL_DeleteContext(_this, context);
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        SDL_SetError ("Failed getting OpenGL context version");
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        return NULL;
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    }
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    if (SDL_sscanf(glversion, "%d.%d", &glversion_major, &glversion_minor) != 2) {
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        Cocoa_GL_DeleteContext(_this, context);
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        SDL_SetError ("Failed parsing OpenGL context version");
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        return NULL;
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    }
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    if ((glversion_major <  _this->gl_config.major_version) ||
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       ((glversion_major == _this->gl_config.major_version) && (glversion_minor < _this->gl_config.minor_version))) {
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        Cocoa_GL_DeleteContext(_this, context);
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        SDL_SetError ("Failed creating OpenGL context at version requested");
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        return NULL;
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    }
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    _this->gl_config.major_version = glversion_major;
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    _this->gl_config.minor_version = glversion_minor;
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    return context;
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}
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int
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Cocoa_GL_MakeCurrent(_THIS, SDL_Window * window, SDL_GLContext context)
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{
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    NSAutoreleasePool *pool;
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    pool = [[NSAutoreleasePool alloc] init];
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    if (context) {
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        SDLOpenGLContext *nscontext = (SDLOpenGLContext *)context;
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        [nscontext setWindow:window];
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        [nscontext updateIfNeeded];
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        [nscontext makeCurrentContext];
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    } else {
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        [NSOpenGLContext clearCurrentContext];
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    }
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    [pool release];
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    return 0;
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}
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void
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Cocoa_GL_GetDrawableSize(_THIS, SDL_Window * window, int * w, int * h)
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{
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    SDL_WindowData *windata = (SDL_WindowData *) window->driverdata;
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    NSView *contentView = [windata->nswindow contentView];
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    NSRect viewport = [contentView bounds];
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    /* This gives us the correct viewport for a Retina-enabled view, only
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     * supported on 10.7+. */
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    if ([contentView respondsToSelector:@selector(convertRectToBacking:)]) {
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        viewport = [contentView convertRectToBacking:viewport];
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    }
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    if (w) {
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        *w = viewport.size.width;
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    }
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    if (h) {
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        *h = viewport.size.height;
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    }
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}
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int
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Cocoa_GL_SetSwapInterval(_THIS, int interval)
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{
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    NSAutoreleasePool *pool;
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    NSOpenGLContext *nscontext;
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    GLint value;
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    int status;
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    if (interval < 0) {  /* no extension for this on Mac OS X at the moment. */
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        return SDL_SetError("Late swap tearing currently unsupported");
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    }
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    pool = [[NSAutoreleasePool alloc] init];
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    nscontext = (NSOpenGLContext*)SDL_GL_GetCurrentContext();
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    if (nscontext != nil) {
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        value = interval;
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        [nscontext setValues:&value forParameter:NSOpenGLCPSwapInterval];
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        status = 0;
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   373
    } else {
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   374
        status = SDL_SetError("No current OpenGL context");
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   375
    }
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   376
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   377
    [pool release];
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   378
    return status;
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   379
}
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   380
slouken@1936
   381
int
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   382
Cocoa_GL_GetSwapInterval(_THIS)
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   383
{
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   384
    NSAutoreleasePool *pool;
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   385
    NSOpenGLContext *nscontext;
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   386
    GLint value;
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   387
    int status = 0;
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   388
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   389
    pool = [[NSAutoreleasePool alloc] init];
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   390
jorgen@7594
   391
    nscontext = (NSOpenGLContext*)SDL_GL_GetCurrentContext();
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   392
    if (nscontext != nil) {
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   393
        [nscontext getValues:&value forParameter:NSOpenGLCPSwapInterval];
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   394
        status = (int)value;
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   395
    }
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   396
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   397
    [pool release];
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   398
    return status;
slouken@1936
   399
}
slouken@1936
   400
slouken@1936
   401
void
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   402
Cocoa_GL_SwapWindow(_THIS, SDL_Window * window)
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   403
{
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   404
    NSAutoreleasePool *pool;
slouken@1936
   405
slouken@6848
   406
    pool = [[NSAutoreleasePool alloc] init];
slouken@6848
   407
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   408
    SDLOpenGLContext* nscontext = (SDLOpenGLContext*)SDL_GL_GetCurrentContext();
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   409
    [nscontext flushBuffer];
jorgen@7594
   410
    [nscontext updateIfNeeded];
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   411
slouken@6848
   412
    [pool release];
slouken@1936
   413
}
slouken@1936
   414
slouken@1936
   415
void
slouken@1936
   416
Cocoa_GL_DeleteContext(_THIS, SDL_GLContext context)
slouken@1936
   417
{
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   418
    NSAutoreleasePool *pool;
jorgen@7595
   419
    SDLOpenGLContext *nscontext = (SDLOpenGLContext *)context;
slouken@1936
   420
slouken@6848
   421
    pool = [[NSAutoreleasePool alloc] init];
slouken@6848
   422
jorgen@7595
   423
    [nscontext setWindow:NULL];
slouken@6848
   424
    [nscontext release];
slouken@6848
   425
slouken@6848
   426
    [pool release];
slouken@1936
   427
}
slouken@1936
   428
slouken@1952
   429
#endif /* SDL_VIDEO_OPENGL_CGL */
slouken@1936
   430
slouken@1936
   431
/* vi: set ts=4 sw=4 expandtab: */