do not call loop from displaylink callback and pause displaylink befo…

include/SDL_system.h

@@ -180,6 +180,8 @@ extern DECLSPEC int SDLCALL SDL_LinuxSetThreadPriority(Sint64 threadID, int prio
  */
 extern DECLSPEC int SDLCALL SDL_iPhoneSetAnimationCallback(SDL_Window * window, int interval, void (*callback)(void*), void *callbackParam);
 
+extern DECLSPEC void SDLCALL SDL_iPhoneRunOnMainLoop(void (*callback)(void));
+
 #define SDL_iOSSetEventPump(enabled) SDL_iPhoneSetEventPump(enabled)
 
 /**

include/SDL_video.h

@@ -278,6 +278,9 @@ typedef enum
 
 /* Function prototypes */
 
+extern DECLSPEC void SDLCALL SDL_PauseDisplayLink(void);
+extern DECLSPEC void SDLCALL SDL_ResumeDisplayLink(void);
+
 /**
  * Get the number of video drivers compiled into SDL.
  *

src/video/SDL_sysvideo.h

@@ -308,6 +308,9 @@ struct SDL_VideoDevice
     void (*ShowScreenKeyboard) (_THIS, SDL_Window *window);
     void (*HideScreenKeyboard) (_THIS, SDL_Window *window);
     SDL_bool (*IsScreenKeyboardShown) (_THIS, SDL_Window *window);
+
+    void (*PauseDisplayLink)(_THIS, SDL_Window *window);
+    void (*ResumeDisplayLink)(_THIS, SDL_Window *window);
 
     /* Clipboard */
     int (*SetClipboardText) (_THIS, const char *text);

src/video/SDL_video.c

@@ -4043,6 +4043,24 @@ SDL_StartTextInput(void)
     }
 }
 
+void SDL_PauseDisplayLink(void) {
+    SDL_Window *window;
+    window = SDL_GetFocusWindow();
+
+    if (window && _this && _this->PauseDisplayLink) {
+        _this->PauseDisplayLink(_this, window);
+    }
+}
+
+void SDL_ResumeDisplayLink(void) {
+    SDL_Window *window;
+    window = SDL_GetFocusWindow();
+
+    if (window && _this && _this->ResumeDisplayLink) {
+        _this->ResumeDisplayLink(_this, window);
+    }
+}
+
 SDL_bool
 SDL_IsTextInputActive(void)
 {
@@ -4213,11 +4231,13 @@ SDL_ShowMessageBox(const SDL_MessageBoxData *messageboxdata, int *buttonid)
     }
 #endif
 #if SDL_VIDEO_DRIVER_UIKIT
+    SDL_PauseDisplayLink();
     if (retval == -1 &&
         SDL_MessageboxValidForDriver(messageboxdata, SDL_SYSWM_UIKIT) &&
         UIKit_ShowMessageBox(messageboxdata, buttonid) == 0) {
         retval = 0;
     }
+    SDL_ResumeDisplayLink();
 #endif
 #if SDL_VIDEO_DRIVER_X11
     if (retval == -1 &&

src/video/uikit/SDL_uikitvideo.m

@@ -106,6 +106,9 @@ static void UIKit_DeleteDevice(SDL_VideoDevice * device)
         device->IsScreenKeyboardShown = UIKit_IsScreenKeyboardShown;
         device->SetTextInputRect = UIKit_SetTextInputRect;
 #endif
+
+        device->PauseDisplayLink = UIKit_PauseDisplayLink;
+        device->ResumeDisplayLink = UIKit_ResumeDisplayLink;
 
         device->SetClipboardText = UIKit_SetClipboardText;
         device->GetClipboardText = UIKit_GetClipboardText;

src/video/uikit/SDL_uikitviewcontroller.h

@@ -49,6 +49,8 @@
 
 - (void)startAnimation;
 - (void)stopAnimation;
+- (void)pauseAnimation;
+- (void)resumeAnimation;
 
 - (void)doLoop:(CADisplayLink*)sender;
 
@@ -89,3 +91,6 @@ void UIKit_HideScreenKeyboard(_THIS, SDL_Window *window);
 SDL_bool UIKit_IsScreenKeyboardShown(_THIS, SDL_Window *window);
 void UIKit_SetTextInputRect(_THIS, SDL_Rect *rect);
 #endif
+
+void UIKit_PauseDisplayLink(_THIS, SDL_Window *window);
+void UIKit_ResumeDisplayLink(_THIS, SDL_Window *window);

src/video/uikit/SDL_uikitviewcontroller.m

@@ -175,6 +175,16 @@ - (void)stopAnimation
     displayLink = nil;
 }
 
+- (void)pauseAnimation
+{
+    [displayLink removeFromRunLoop:[NSRunLoop currentRunLoop] forMode:NSDefaultRunLoopMode];
+}
+
+- (void)resumeAnimation
+{
+    [displayLink addToRunLoop:[NSRunLoop currentRunLoop] forMode:NSDefaultRunLoopMode];
+}
+
 - (void)doLoop:(CADisplayLink*)sender
 {
     /* Don't run the game loop while a messagebox is up */
@@ -547,6 +557,20 @@ - (BOOL)textFieldShouldReturn:(UITextField*)_textField
     return data.viewcontroller;
 }
 
+void UIKit_PauseDisplayLink(_THIS, SDL_Window *window) {
+    @autoreleasepool {
+        SDL_uikitviewcontroller *vc = GetWindowViewController(window);
+        [vc pauseAnimation];
+    }
+}
+
+void UIKit_ResumeDisplayLink(_THIS, SDL_Window *window) {
+    @autoreleasepool {
+        SDL_uikitviewcontroller *vc = GetWindowViewController(window);
+        [vc resumeAnimation];
+    }
+}
+
 SDL_bool
 UIKit_HasScreenKeyboardSupport(_THIS)
 {

src/video/uikit/SDL_uikitwindow.m

@@ -486,6 +486,13 @@ - (void)layoutSubviews
 
     return 0;
 }
+
+void SDL_iPhoneRunOnMainLoop(void (*callback)(void))
+{
+    dispatch_async(dispatch_get_main_queue(), ^{
+        callback();
+    });
+}
 
 #endif /* SDL_VIDEO_DRIVER_UIKIT */
 

test/testsprite2.c

@@ -503,7 +503,10 @@ loop()
         next_fps_check = now + fps_check_delay;
         frames = 0;
     }
+}
 
+void LoopWrapper() {
+    SDL_iPhoneRunOnMainLoop(loop);
 }
 
 int
@@ -659,7 +662,7 @@ main(int argc, char *argv[])
     {
         // Set up the game to run in the window animation callback on iOS
         // so that Game Center and so forth works correctly.
-        SDL_iPhoneSetAnimationCallback(state->windows[0], 1, loop, NULL);
+        SDL_iPhoneSetAnimationCallback(state->windows[0], 1, LoopWrapper, NULL);
         //while (!done) {
             //loop();
             //SDL_iPhoneSetAnimationCallback(state->windows[0], 1, loop, NULL);
@@ -669,10 +672,10 @@ main(int argc, char *argv[])
         while (!done) {
             loop();
         }
+        quit(0);
     }
 #endif
 
-    //quit(0);
     return 0;
 }