From e7de2bbc9ef89fbd9635c6f0355f27a99b502530 Mon Sep 17 00:00:00 2001
From: Arseny Kapoulkine <arseny.kapoulkine@gmail.com>
Date: Thu, 1 May 2014 22:39:21 -0700
Subject: [PATCH] Optimize _glfwInitJoysticks on OS X.

This function used to enumerate all devices and capture all properties
of every device into a dictionary. This takes 180 ms on a MacBook Pro
without external devices and 280 ms with an external keyboard/mouse
attached.

Since we're only interested in a few properties, we can just get them
one by one - this reduces the time to <1 ms.

Note that we still use the dictionary to get the joystick elements.
For unknown reason this is required to get all axes/buttons - without
doing this we don't get any joystick elements in addJoystickElement.

Closes #332.
---
 src/iokit_joystick.m | 65 ++++++++++++++++++++++++--------------------
 1 file changed, 35 insertions(+), 30 deletions(-)

diff --git a/src/iokit_joystick.m b/src/iokit_joystick.m
index a09fbcf3e..5ff67dd8e 100644
--- a/src/iokit_joystick.m
+++ b/src/iokit_joystick.m
@@ -324,44 +324,49 @@ void _glfwInitJoysticks(void)
         HRESULT plugInResult = S_OK;
         SInt32 score = 0;
 
-        long usagePage, usage;
+        long usagePage = 0;
+        long usage = 0;
 
-        // Check device type
+        valueRef = IORegistryEntryCreateCFProperty(ioHIDDeviceObject,
+                                                   CFSTR(kIOHIDPrimaryUsagePageKey),
+                                                   kCFAllocatorDefault, kNilOptions);
+        if (valueRef)
+        {
+            CFNumberGetValue(valueRef, kCFNumberLongType, &usagePage);
+            CFRelease(valueRef);
+        }
+
+        valueRef = IORegistryEntryCreateCFProperty(ioHIDDeviceObject,
+                                                   CFSTR(kIOHIDPrimaryUsageKey),
+                                                   kCFAllocatorDefault, kNilOptions);
+        if (valueRef)
+        {
+            CFNumberGetValue(valueRef, kCFNumberLongType, &usage);
+            CFRelease(valueRef);
+        }
+
+        if (usagePage != kHIDPage_GenericDesktop)
+        {
+            // This device is not relevant to GLFW
+            continue;
+        }
+
+        if ((usage != kHIDUsage_GD_Joystick &&
+             usage != kHIDUsage_GD_GamePad &&
+             usage != kHIDUsage_GD_MultiAxisController))
+        {
+            // This device is not relevant to GLFW
+            continue;
+        }
+        
         result = IORegistryEntryCreateCFProperties(ioHIDDeviceObject,
                                                    &propsRef,
                                                    kCFAllocatorDefault,
                                                    kNilOptions);
-
+        
         if (result != kIOReturnSuccess)
             continue;
 
-        valueRef = CFDictionaryGetValue(propsRef, CFSTR(kIOHIDPrimaryUsagePageKey));
-        if (valueRef)
-        {
-            CFNumberGetValue(valueRef, kCFNumberLongType, &usagePage);
-            if (usagePage != kHIDPage_GenericDesktop)
-            {
-                // This device is not relevant to GLFW
-                CFRelease(propsRef);
-                continue;
-            }
-        }
-
-        valueRef = CFDictionaryGetValue(propsRef, CFSTR(kIOHIDPrimaryUsageKey));
-        if (valueRef)
-        {
-            CFNumberGetValue(valueRef, kCFNumberLongType, &usage);
-
-            if ((usage != kHIDUsage_GD_Joystick &&
-                 usage != kHIDUsage_GD_GamePad &&
-                 usage != kHIDUsage_GD_MultiAxisController))
-            {
-                // This device is not relevant to GLFW
-                CFRelease(propsRef);
-                continue;
-            }
-        }
-
         _GLFWjoystickIOKit* joystick = _glfw.iokit_js + joy;
         joystick->present = GL_TRUE;