commit d6f28e8bd23ac17a624d054a406551ebf39da7f2
author Ryan C. Gordon <icculus@icculus.org> Tue Apr 07 14:01:25 2020 -0400
committer Ryan C. Gordon <icculus@icculus.org> Tue Apr 07 14:01:25 2020 -0400
tree 3532199b6d474aaa687f782d1b02e6ca8b04a664
parent d480825910c07851f7f49f7aab26d9d87583b029

cocoa: OpenGL setView and update must be used on main thread (thanks, Tim!).

If called from background threads, use Grand Central Dispatch to use the
main thread instead. On the main thread, just call them directly.

Fixes Bugzilla #4932.

--HG--
extra : rebase_source : f902bad5141444e127ccb6d526246e88465dde80

src/video/cocoa/SDL_cocoaopengl.h

diff --git a/src/video/cocoa/SDL_cocoaopengl.h b/src/video/cocoa/SDL_cocoaopengl.h
index 5debd23..bae8ce4 100644
--- a/src/video/cocoa/SDL_cocoaopengl.h
+++ b/src/video/cocoa/SDL_cocoaopengl.h
@@ -49,6 +49,8 @@
 - (void)scheduleUpdate;
 - (void)updateIfNeeded;
 - (void)setWindow:(SDL_Window *)window;
+- (SDL_Window*)window;
+- (void)explicitUpdate;
 
 @end
 

src/video/cocoa/SDL_cocoaopengl.m

diff --git a/src/video/cocoa/SDL_cocoaopengl.m b/src/video/cocoa/SDL_cocoaopengl.m
index c4db256..257f1a5 100644
--- a/src/video/cocoa/SDL_cocoaopengl.m
+++ b/src/video/cocoa/SDL_cocoaopengl.m
@@ -63,14 +63,10 @@
 /* This should only be called on the thread on which a user is using the context. */
 - (void)updateIfNeeded
 {
-    int value = SDL_AtomicSet(&self->dirty, 0);
+    const int value = SDL_AtomicSet(&self->dirty, 0);
     if (value > 0) {
         /* We call the real underlying update here, since -[SDLOpenGLContext update] just calls us. */
-        if ([NSThread isMainThread]) {
-            [super update];
-        } else {
-            [super performSelectorOnMainThread:@selector(update) withObject:nil waitUntilDone:NO];
-        }
+        [self explicitUpdate];
     }
 }
 
@@ -119,9 +115,13 @@
         }
 
         if ([self view] != contentview) {
-            [self setView:contentview];
+            if ([NSThread isMainThread]) {
+                [self setView:contentview];
+            } else {
+                dispatch_sync(dispatch_get_main_queue(), ^{ [self setView:contentview]; });
+            }
             if (self == [NSOpenGLContext currentContext]) {
-                [self update];
+                [self explicitUpdate];
             } else {
                 [self scheduleUpdate];
             }
@@ -129,13 +129,27 @@
     } else {
         [self clearDrawable];
         if (self == [NSOpenGLContext currentContext]) {
-            [self update];
+            [self explicitUpdate];
         } else {
             [self scheduleUpdate];
         }
     }
 }
 
+- (SDL_Window*)window
+{
+    return self->window;
+}
+
+- (void)explicitUpdate
+{
+    if ([NSThread isMainThread]) {
+        [super update];
+    } else {
+        dispatch_sync(dispatch_get_main_queue(), ^{ [super update]; });
+    }
+}
+
 @end
 
 
@@ -352,8 +366,10 @@
 {
     if (context) {
         SDLOpenGLContext *nscontext = (SDLOpenGLContext *)context;
-        [nscontext setWindow:window];
-        [nscontext updateIfNeeded];
+        if ([nscontext window] != window) {
+            [nscontext setWindow:window];
+            [nscontext updateIfNeeded];
+        }
         [nscontext makeCurrentContext];
     } else {
         [NSOpenGLContext clearCurrentContext];