Updating Blink-side WebGamepad interface

public/platform/WebGamepad.h

Index: public/platform/WebGamepad.h
diff --git a/public/platform/WebGamepad.h b/public/platform/WebGamepad.h
index 93df8a28b67adaa5022aa13843b26a0908fe5a67..db1fa1c012da5eaa2279c9f0454a9c2c530f236d 100644
--- a/public/platform/WebGamepad.h
+++ b/public/platform/WebGamepad.h
@@ -34,12 +34,31 @@ namespace blink {
 
 #pragma pack(push, 1)
 
+#if defined(ENABLE_NEW_GAMEPAD_API)
+class WebGamepadButton {
+public:
+    WebGamepadButton()
+        : pressed(false)
+        , value(0.f)
+    {
+    }
+    WebGamepadButton(bool pressed, float value)
+        : pressed(pressed)
+        , value(value)
+    {
+    }
+    bool pressed;
+    float value;
+};
+#endif
+
 // This structure is intentionally POD and fixed size so that it can be shared
 // memory between hardware polling threads and the rest of the browser. See
 // also WebGamepads.h.
 class WebGamepad {
 public:
     static const size_t idLengthCap = 128;
+    static const size_t mappingLengthCap = 16;
     static const size_t axesLengthCap = 16;
     static const size_t buttonsLengthCap = 32;
 
@@ -50,6 +69,9 @@ public:
         , buttonsLength(0)
     {
         id[0] = 0;
+#if defined(ENABLE_NEW_GAMEPAD_API)
+        mapping[0] = 0;
+#endif
     }
 
     // Is there a gamepad connected at this index?
@@ -71,13 +93,24 @@ public:
     // Number of valid entries in the buttons array.
     unsigned buttonsLength;
 
-    // Normalized values representing buttons, in the range [0..1].
+#if defined(ENABLE_NEW_GAMEPAD_API)
+    // Button states
+    WebGamepadButton buttons[buttonsLengthCap];
+
+    // Mapping type (for example "standard")
+    WebUChar mapping[mappingLengthCap];
+#else
     float buttons[buttonsLengthCap];
+#endif
 };
 
 #if BLINK_IMPLEMENTATION
+#if defined(ENABLE_NEW_GAMEPAD_API)
+COMPILE_ASSERT(sizeof(WebGamepad) == 529, WebGamepad_has_wrong_size);
+#else
 COMPILE_ASSERT(sizeof(WebGamepad) == 465, WebGamepad_has_wrong_size);
 #endif
+#endif

[abarth-chromium, 2014/02/20 06:12:45]

What's the point of these COMPILE_ASSERTs if we're just going to change them to
some random value?

[bajones, 2014/02/20 17:03:24]

Truthfully I'm not sure. The class must be a static size, consist of POD types,
and there are PPAPI structures that must match it exactly (which has it's own
compile-time check). I don't think this check helps enforce any of those goals,
though. It seems like more of an annoyance to me than anything. Maybe scottmg@
has some insight?

 
 #pragma pack(pop)