diff -r 000000000000 -r 6474c204b198 gfx/skia/trunk/include/utils/SkWGL.h
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/gfx/skia/trunk/include/utils/SkWGL.h	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,115 @@
+
+/*
+ * Copyright 2011 Google Inc.
+ *
+ * Use of this source code is governed by a BSD-style license that can be
+ * found in the LICENSE file.
+ */
+
+#include "SkRefCnt.h"
+
+#ifndef SkWGL_DEFINED
+#define SkWGL_DEFINED
+
+/**
+ * Working with WGL extensions can be a pain. Among the reasons is that You must
+ * have a GL context to get the proc addresses, but you want to use the procs to
+ * create a context in the first place. So you have to create a dummy GL ctx to
+ * get the proc addresses.
+ *
+ * This file helps by providing SkCreateWGLInterface(). It returns a struct of
+ * function pointers that it initializes. It also has a helper function to query
+ * for WGL extensions. It handles the fact that wglGetExtensionsString is itself
+ * an extension.
+ */
+
+#if !defined(WIN32_LEAN_AND_MEAN)
+    #define WIN32_LEAN_AND_MEAN
+    #define SK_LOCAL_LEAN_AND_MEAN
+#endif
+#include <windows.h>
+#if defined(SK_LOCAL_LEAN_AND_MEAN)
+    #undef WIN32_LEAN_AND_MEAN
+    #undef SK_LOCAL_LEAN_AND_MEAN
+#endif
+
+#define SK_WGL_DRAW_TO_WINDOW                       0x2001
+#define SK_WGL_ACCELERATION                         0x2003
+#define SK_WGL_SUPPORT_OPENGL                       0x2010
+#define SK_WGL_DOUBLE_BUFFER                        0x2011
+#define SK_WGL_COLOR_BITS                           0x2014
+#define SK_WGL_ALPHA_BITS                           0x201B
+#define SK_WGL_STENCIL_BITS                         0x2023
+#define SK_WGL_FULL_ACCELERATION                    0x2027
+#define SK_WGL_SAMPLE_BUFFERS                       0x2041
+#define SK_WGL_SAMPLES                              0x2042
+#define SK_WGL_CONTEXT_MAJOR_VERSION                0x2091
+#define SK_WGL_CONTEXT_MINOR_VERSION                0x2092
+#define SK_WGL_CONTEXT_LAYER_PLANE                  0x2093
+#define SK_WGL_CONTEXT_FLAGS                        0x2094
+#define SK_WGL_CONTEXT_PROFILE_MASK                 0x9126
+#define SK_WGL_CONTEXT_DEBUG_BIT                    0x0001
+#define SK_WGL_CONTEXT_FORWARD_COMPATIBLE_BIT       0x0002
+#define SK_WGL_CONTEXT_CORE_PROFILE_BIT             0x00000001
+#define SK_WGL_CONTEXT_COMPATIBILITY_PROFILE_BIT    0x00000002
+#define SK_WGL_CONTEXT_ES2_PROFILE_BIT              0x00000004
+#define SK_ERROR_INVALID_VERSION                    0x2095
+#define SK_ERROR_INVALID_PROFILE                    0x2096
+
+class SkWGLExtensions {
+public:
+    SkWGLExtensions();
+    /**
+     * Determines if an extensions is available for a given DC.
+     * WGL_extensions_string is considered a prerequisite for all other
+     * extensions. It is necessary to check this before calling other class
+     * functions.
+     */
+    bool hasExtension(HDC dc, const char* ext) const;
+
+    const char* getExtensionsString(HDC hdc) const;
+    BOOL choosePixelFormat(HDC hdc, const int*, const FLOAT*, UINT, int*, UINT*) const;
+    BOOL getPixelFormatAttribiv(HDC, int, int, UINT, const int*, int*) const;
+    BOOL getPixelFormatAttribfv(HDC hdc, int, int, UINT, const int*, FLOAT*) const;
+    HGLRC createContextAttribs(HDC, HGLRC, const int *) const;
+
+    /**
+     * WGL doesn't have precise rules for the ordering of formats returned
+     * by wglChoosePixelFormat. This function helps choose among the set of
+     * formats returned by wglChoosePixelFormat. The rules in decreasing
+     * priority are:
+     *     * Choose formats with the smallest sample count that is >=
+     *       desiredSampleCount (or the largest sample count if all formats have
+     *       fewer samples than desiredSampleCount.)
+     *     * Choose formats with the fewest color samples when coverage sampling
+     *       is available.
+     *     * If the above rules leave multiple formats, choose the one that
+     *       appears first in the formats array parameter.
+     */
+    int selectFormat(const int formats[],
+                     int formatCount,
+                     HDC dc,
+                     int desiredSampleCount);
+private:
+    typedef const char* (WINAPI *GetExtensionsStringProc)(HDC hdc);
+    typedef BOOL (WINAPI *ChoosePixelFormatProc)(HDC hdc, const int *, const FLOAT *, UINT, int *, UINT *);
+    typedef BOOL (WINAPI *GetPixelFormatAttribivProc)(HDC, int, int, UINT, const int*, int*);
+    typedef BOOL (WINAPI *GetPixelFormatAttribfvProc)(HDC hdc, int, int, UINT, const int*, FLOAT*);
+    typedef HGLRC (WINAPI *CreateContextAttribsProc)(HDC hDC, HGLRC, const int *);
+
+    GetExtensionsStringProc fGetExtensionsString;
+    ChoosePixelFormatProc fChoosePixelFormat;
+    GetPixelFormatAttribfvProc fGetPixelFormatAttribfv;
+    GetPixelFormatAttribivProc fGetPixelFormatAttribiv;
+    CreateContextAttribsProc fCreateContextAttribs;
+};
+
+/**
+ * Helper to create an OpenGL context for a DC using WGL. Configs with a sample count >= to
+ * msaaSampleCount are preferred but if none is available then a context with a lower sample count
+ * (including non-MSAA) will be created. If preferCoreProfile is true but a core profile cannot be
+ * created then a compatible profile context will be created.
+ */
+HGLRC SkCreateWGLContext(HDC dc, int msaaSampleCount, bool preferCoreProfile);
+
+#endif