added resizing to osx window

engine/main.cpp

@@ -85,10 +85,18 @@ static CVReturn MyDisplayLinkCallback(CVDisplayLinkRef displayLink, const CVTime
         // Add your drawing codes here
         [[self openGLContext] makeCurrentContext];
 
+        // We draw on a secondary thread through the display link
+        // When resizing the view, -reshape is called automatically on the main
+        // thread. Add a mutex around to avoid the threads accessing the context
+        // simultaneously when resizing
+        CGLLockContext([[self openGLContext] CGLContextObj]);
         App::I.update(now - _prevTime);
         
-        [[self openGLContext] flushBuffer];
+        //[[self openGLContext] flushBuffer];
         // returning NO will cause the layer to NOT be redrawn
+        
+        CGLFlushDrawable([[self openGLContext] CGLContextObj]);
+        CGLUnlockContext([[self openGLContext] CGLContextObj]);
         return NO;
     }
     else
@@ -111,6 +119,78 @@ static CVReturn MyDisplayLinkCallback(CVDisplayLinkRef displayLink, const CVTime
 - (void)drawRect:(NSRect)dirtyRect
 {
     NSLog(@"drawRect");
+    // Add your drawing codes here
+    [[self openGLContext] makeCurrentContext];
+    
+    // We draw on a secondary thread through the display link
+    // When resizing the view, -reshape is called automatically on the main
+    // thread. Add a mutex around to avoid the threads accessing the context
+    // simultaneously when resizing
+    CGLLockContext([[self openGLContext] CGLContextObj]);
+    App::I.update(0);
+    
+    //[[self openGLContext] flushBuffer];
+    // returning NO will cause the layer to NOT be redrawn
+    
+    CGLFlushDrawable([[self openGLContext] CGLContextObj]);
+    CGLUnlockContext([[self openGLContext] CGLContextObj]);
+}
+
+- (void)reshape
+{
+    [super reshape];
+    
+    // We draw on a secondary thread through the display link. However, when
+    // resizing the view, -drawRect is called on the main thread.
+    // Add a mutex around to avoid the threads accessing the context
+    // simultaneously when resizing.
+    CGLLockContext([[self openGLContext] CGLContextObj]);
+    
+    // Get the view size in Points
+    NSRect viewRectPoints = [self bounds];
+    
+#if SUPPORT_RETINA_RESOLUTION
+    
+    // Rendering at retina resolutions will reduce aliasing, but at the potential
+    // cost of framerate and battery life due to the GPU needing to render more
+    // pixels.
+    
+    // Any calculations the renderer does which use pixel dimentions, must be
+    // in "retina" space.  [NSView convertRectToBacking] converts point sizes
+    // to pixel sizes.  Thus the renderer gets the size in pixels, not points,
+    // so that it can set it's viewport and perform and other pixel based
+    // calculations appropriately.
+    // viewRectPixels will be larger than viewRectPoints for retina displays.
+    // viewRectPixels will be the same as viewRectPoints for non-retina displays
+    NSRect viewRectPixels = [self convertRectToBacking:viewRectPoints];
+    
+#else //if !SUPPORT_RETINA_RESOLUTION
+    
+    // App will typically render faster and use less power rendering at
+    // non-retina resolutions since the GPU needs to render less pixels.
+    // There is the cost of more aliasing, but it will be no-worse than
+    // on a Mac without a retina display.
+    
+    // Points:Pixels is always 1:1 when not supporting retina resolutions
+    NSRect viewRectPixels = viewRectPoints;
+    
+#endif // !SUPPORT_RETINA_RESOLUTION
+    App::I.resize(viewRectPixels.size.width, viewRectPixels.size.height);
+    
+    CGLUnlockContext([[self openGLContext] CGLContextObj]);
+}
+- (void)renewGState
+{
+    // Called whenever graphics state updated (such as window resize)
+    
+    // OpenGL rendering is not synchronous with other rendering on the OSX.
+    // Therefore, call disableScreenUpdatesUntilFlush so the window server
+    // doesn't render non-OpenGL content in the window asynchronously from
+    // OpenGL content, which could cause flickering.  (non-OpenGL content
+    // includes the title bar and drawing done by the app with other APIs)
+    [[self window] disableScreenUpdatesUntilFlush];
+    
+    [super renewGState];
 }
 @end
 
@@ -122,7 +202,7 @@ static CVReturn MyDisplayLinkCallback(CVDisplayLinkRef displayLink, const CVTime
 }
 @end
 
-@interface Controller : NSWindowController
+@interface Controller : NSWindowController<NSWindowDelegate>
 @end @implementation Controller
 - (void)keyDown:(NSEvent *)theEvent
 {
@@ -131,6 +211,10 @@ static CVReturn MyDisplayLinkCallback(CVDisplayLinkRef displayLink, const CVTime
     {
         [[NSApplication sharedApplication] terminate:nil];
     }
+}
+- (void)windowDidResize:(NSNotification *)notification
+{
+    
 }
 @end
 
@@ -156,10 +240,8 @@ static CVReturn MyDisplayLinkCallback(CVDisplayLinkRef displayLink, const CVTime
 
     view = [[View alloc] initWithFrame:r];
     
-    window = [[Window alloc] initWithContentRect:r
-                                       styleMask:NSTitledWindowMask|NSMiniaturizableWindowMask
-                                         backing:NSBackingStoreBuffered
-                                           defer:NO];
+    auto style = NSTitledWindowMask|NSMiniaturizableWindowMask|NSResizableWindowMask;
+    window = [[Window alloc] initWithContentRect:r styleMask:style backing:NSBackingStoreBuffered defer:NO];
     [window setTitle:@"hello engine - ui shapes"];
     [window center];
     [window makeKeyAndOrderFront:controller];