call NSOpenGLContext 'update' on opengl context on macos when resizing

libobs-opengl/gl-cocoa.m

@@ -220,6 +220,11 @@ void gl_windowinfo_destroy(struct gl_windowinfo *wi)
 	bfree(wi);
 }
 
+void gl_update(device_t device)
+{
+	[debug->play->context update]
+}
+
 void device_entercontext(device_t device)
 {
 	[device->plat->context makeCurrentContext];

libobs-opengl/gl-subsystem.c

@@ -135,6 +135,8 @@ void device_resize(device_t device, uint32_t cx, uint32_t cy)
 	/* GL automatically resizes the device, so it doesn't do much */
 	device->cur_swap->info.cx = cx;
 	device->cur_swap->info.cy = cy;
+
+	gl_update(device);
 }
 
 void device_getsize(device_t device, uint32_t *cx, uint32_t *cy)

libobs-opengl/gl-subsystem.h

@@ -481,6 +481,8 @@ struct gs_device {
 	struct fbo_info          *cur_fbo;
 };
 
+extern void                  gl_update(device_t device);
+
 extern struct gl_platform   *gl_platform_create(device_t device,
                                                 struct gs_init_data *info);
 extern struct gs_swap_chain *gl_platform_getswap(struct gl_platform *platform);

libobs-opengl/gl-windows.c

@@ -390,6 +390,11 @@ static void APIENTRY gl_debug_message_amd(GLuint id,
 }
 #endif
 
+void gl_update(device_t device)
+{
+	/* does nothing on windows */
+}
+
 struct gl_platform *gl_platform_create(device_t device,
 		struct gs_init_data *info)
 {