SDL  2.0
SDL_uikitopengles.m
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1 /*
2  Simple DirectMedia Layer
3  Copyright (C) 1997-2016 Sam Lantinga <slouken@libsdl.org>
4 
5  This software is provided 'as-is', without any express or implied
6  warranty. In no event will the authors be held liable for any damages
7  arising from the use of this software.
8 
9  Permission is granted to anyone to use this software for any purpose,
10  including commercial applications, and to alter it and redistribute it
11  freely, subject to the following restrictions:
12 
13  1. The origin of this software must not be misrepresented; you must not
14  claim that you wrote the original software. If you use this software
15  in a product, an acknowledgment in the product documentation would be
16  appreciated but is not required.
17  2. Altered source versions must be plainly marked as such, and must not be
18  misrepresented as being the original software.
19  3. This notice may not be removed or altered from any source distribution.
20 */
21 #include "../../SDL_internal.h"
22 
23 #if SDL_VIDEO_DRIVER_UIKIT
24 
25 #include "SDL_uikitopengles.h"
26 #import "SDL_uikitopenglview.h"
27 #include "SDL_uikitmodes.h"
28 #include "SDL_uikitwindow.h"
29 #include "SDL_uikitevents.h"
30 #include "../SDL_sysvideo.h"
31 #include "../../events/SDL_keyboard_c.h"
32 #include "../../events/SDL_mouse_c.h"
33 #include "../../power/uikit/SDL_syspower.h"
34 #include "SDL_loadso.h"
35 #include <dlfcn.h>
36 
37 @interface SDLEAGLContext : EAGLContext
38 
39 /* The OpenGL ES context owns a view / drawable. */
40 @property (nonatomic, strong) SDL_uikitopenglview *sdlView;
41 
42 @end
43 
44 @implementation SDLEAGLContext
45 
46 - (void)dealloc
47 {
48  /* When the context is deallocated, its view should be removed from any
49  * SDL window that it's attached to. */
50  [self.sdlView setSDLWindow:NULL];
51 }
52 
53 @end
54 
55 void *
56 UIKit_GL_GetProcAddress(_THIS, const char *proc)
57 {
58  /* Look through all SO's for the proc symbol. Here's why:
59  * -Looking for the path to the OpenGL Library seems not to work in the iOS Simulator.
60  * -We don't know that the path won't change in the future. */
61  return dlsym(RTLD_DEFAULT, proc);
62 }
63 
64 /*
65  note that SDL_GL_DeleteContext makes it current without passing the window
66 */
67 int
69 {
70  @autoreleasepool {
71  SDLEAGLContext *eaglcontext = (__bridge SDLEAGLContext *) context;
72 
73  if (![EAGLContext setCurrentContext:eaglcontext]) {
74  return SDL_SetError("Could not make EAGL context current");
75  }
76 
77  if (eaglcontext) {
78  [eaglcontext.sdlView setSDLWindow:window];
79  }
80  }
81 
82  return 0;
83 }
84 
85 void
86 UIKit_GL_GetDrawableSize(_THIS, SDL_Window * window, int * w, int * h)
87 {
88  @autoreleasepool {
89  SDL_WindowData *data = (__bridge SDL_WindowData *)window->driverdata;
90  UIView *view = data.viewcontroller.view;
91  if ([view isKindOfClass:[SDL_uikitopenglview class]]) {
92  SDL_uikitopenglview *glview = (SDL_uikitopenglview *) view;
93  if (w) {
94  *w = glview.backingWidth;
95  }
96  if (h) {
97  *h = glview.backingHeight;
98  }
99  }
100  }
101 }
102 
103 int
104 UIKit_GL_LoadLibrary(_THIS, const char *path)
105 {
106  /* We shouldn't pass a path to this function, since we've already loaded the
107  * library. */
108  if (path != NULL) {
109  return SDL_SetError("iOS GL Load Library just here for compatibility");
110  }
111  return 0;
112 }
113 
114 void UIKit_GL_SwapWindow(_THIS, SDL_Window * window)
115 {
116  @autoreleasepool {
117  SDLEAGLContext *context = (__bridge SDLEAGLContext *) SDL_GL_GetCurrentContext();
118 
119 #if SDL_POWER_UIKIT
120  /* Check once a frame to see if we should turn off the battery monitor. */
121  SDL_UIKit_UpdateBatteryMonitoring();
122 #endif
123 
124  [context.sdlView swapBuffers];
125 
126  /* You need to pump events in order for the OS to make changes visible.
127  * We don't pump events here because we don't want iOS application events
128  * (low memory, terminate, etc.) to happen inside low level rendering. */
129  }
130 }
131 
134 {
135  @autoreleasepool {
136  SDLEAGLContext *context = nil;
137  SDL_uikitopenglview *view;
138  SDL_WindowData *data = (__bridge SDL_WindowData *) window->driverdata;
139  CGRect frame = UIKit_ComputeViewFrame(window, data.uiwindow.screen);
140  EAGLSharegroup *sharegroup = nil;
141  CGFloat scale = 1.0;
142  int samples = 0;
143  int major = _this->gl_config.major_version;
144  int minor = _this->gl_config.minor_version;
145 
146  /* The EAGLRenderingAPI enum values currently map 1:1 to major GLES
147  * versions. */
148  EAGLRenderingAPI api = major;
149 
150  /* iOS currently doesn't support GLES >3.0. iOS 6 also only supports up
151  * to GLES 2.0. */
152  if (major > 3 || (major == 3 && (minor > 0 || !UIKit_IsSystemVersionAtLeast(7.0)))) {
153  SDL_SetError("OpenGL ES %d.%d context could not be created", major, minor);
154  return NULL;
155  }
156 
159  }
160 
162  EAGLContext *context = (__bridge EAGLContext *) SDL_GL_GetCurrentContext();
163  sharegroup = context.sharegroup;
164  }
165 
166  if (window->flags & SDL_WINDOW_ALLOW_HIGHDPI) {
167  /* Set the scale to the natural scale factor of the screen - the
168  * backing dimensions of the OpenGL view will match the pixel
169  * dimensions of the screen rather than the dimensions in points. */
170 #ifdef __IPHONE_8_0
171  if ([data.uiwindow.screen respondsToSelector:@selector(nativeScale)]) {
172  scale = data.uiwindow.screen.nativeScale;
173  } else
174 #endif
175  {
176  scale = data.uiwindow.screen.scale;
177  }
178  }
179 
180  context = [[SDLEAGLContext alloc] initWithAPI:api sharegroup:sharegroup];
181  if (!context) {
182  SDL_SetError("OpenGL ES %d context could not be created", _this->gl_config.major_version);
183  return NULL;
184  }
185 
186  /* construct our view, passing in SDL's OpenGL configuration data */
187  view = [[SDL_uikitopenglview alloc] initWithFrame:frame
188  scale:scale
189  retainBacking:_this->gl_config.retained_backing
190  rBits:_this->gl_config.red_size
191  gBits:_this->gl_config.green_size
192  bBits:_this->gl_config.blue_size
193  aBits:_this->gl_config.alpha_size
194  depthBits:_this->gl_config.depth_size
195  stencilBits:_this->gl_config.stencil_size
196  sRGB:_this->gl_config.framebuffer_srgb_capable
197  multisamples:samples
198  context:context];
199 
200  if (!view) {
201  return NULL;
202  }
203 
204  /* The context owns the view / drawable. */
205  context.sdlView = view;
206 
207  if (UIKit_GL_MakeCurrent(_this, window, (__bridge SDL_GLContext) context) < 0) {
208  UIKit_GL_DeleteContext(_this, (SDL_GLContext) CFBridgingRetain(context));
209  return NULL;
210  }
211 
212  /* We return a +1'd context. The window's driverdata owns the view (via
213  * MakeCurrent.) */
214  return (SDL_GLContext) CFBridgingRetain(context);
215  }
216 }
217 
218 void
219 UIKit_GL_DeleteContext(_THIS, SDL_GLContext context)
220 {
221  @autoreleasepool {
222  /* The context was retained in SDL_GL_CreateContext, so we release it
223  * here. The context's view will be detached from its window when the
224  * context is deallocated. */
225  CFRelease(context);
226  }
227 }
228 
229 void
231 {
232  @autoreleasepool {
233  /* Some iOS system functionality (such as Dictation on the on-screen
234  keyboard) uses its own OpenGL ES context but doesn't restore the
235  previous one when it's done. This is a workaround to make sure the
236  expected SDL-created OpenGL ES context is active after the OS is
237  finished running its own code for the frame. If this isn't done, the
238  app may crash or have other nasty symptoms when Dictation is used.
239  */
240  EAGLContext *context = (__bridge EAGLContext *) SDL_GL_GetCurrentContext();
241  if (context != NULL && [EAGLContext currentContext] != context) {
242  [EAGLContext setCurrentContext:context];
243  }
244  }
245 }
246 
247 #endif /* SDL_VIDEO_DRIVER_UIKIT */
248 
249 /* vi: set ts=4 sw=4 expandtab: */
GLenum GLenum GLenum GLenum GLenum scale
SDL_bool UIKit_IsSystemVersionAtLeast(double version)
void UIKit_GL_RestoreCurrentContext()
void UIKit_GL_DeleteContext(_THIS, SDL_GLContext context)
static SDL_Window * window
SDL_uikitviewcontroller * viewcontroller
void UIKit_GL_GetDrawableSize(_THIS, SDL_Window *window, int *w, int *h)
GLint GLenum GLsizei GLsizei GLsizei GLint GLsizei const GLvoid * data
Definition: SDL_opengl.h:1967
int UIKit_GL_LoadLibrary(_THIS, const char *path)
static SDL_VideoDevice * _this
Definition: SDL_video.c:118
struct SDL_VideoDevice::@29 gl_config
void * SDL_GLContext
An opaque handle to an OpenGL context.
Definition: SDL_video.h:172
#define _THIS
int frame
Definition: teststreaming.c:60
GLsizei samples
UIWindow * uiwindow
void UIKit_GL_SwapWindow(_THIS, SDL_Window *window)
SDL_GLContext UIKit_GL_CreateContext(_THIS, SDL_Window *window)
int share_with_current_context
Definition: SDL_sysvideo.h:324
void * UIKit_GL_GetProcAddress(_THIS, const char *proc)
#define NULL
Definition: begin_code.h:143
#define SDL_GL_GetCurrentContext
#define SDL_SetError
SDL_PRINTF_FORMAT_STRING const char int SDL_PRINTF_FORMAT_STRING const char int SDL_PRINTF_FORMAT_STRING const char int SDL_PRINTF_FORMAT_STRING const char const char SDL_SCANF_FORMAT_STRING const char return SDL_ThreadFunction const char void return Uint32 return Uint32 void
The type used to identify a window.
Definition: SDL_sysvideo.h:71
GLsizei const GLchar *const * path
GLubyte GLubyte GLubyte GLubyte w
void * driverdata
Definition: SDL_sysvideo.h:109
Uint32 flags
Definition: SDL_sysvideo.h:81
int UIKit_GL_MakeCurrent(_THIS, SDL_Window *window, SDL_GLContext context)
GLfloat GLfloat GLfloat GLfloat h