Unify wgl context creation.

R=robertphillips@google.com
Review URL: https://codereview.chromium.org/12455009

git-svn-id: http://skia.googlecode.com/svn/trunk/src@7990 2bbb7eff-a529-9590-31e7-b0007b416f81

3 files changed, 111 insertions, 165 deletions

diff --git a/gpu/gl/win/SkNativeGLContext_win.cpp b/gpu/gl/win/SkNativeGLContext_win.cpp
index 00829207..eabc78a9 100644
--- a/gpu/gl/win/SkNativeGLContext_win.cpp
+++ b/gpu/gl/win/SkNativeGLContext_win.cpp
@@ -7,6 +7,7 @@
  */
 
 #include "gl/SkNativeGLContext.h"
+#include "SkWGL.h"
 
 #define WIN32_LEAN_AND_MEAN
 #include <Windows.h>
@@ -49,35 +50,6 @@ void SkNativeGLContext::destroyGLContext() {
 const GrGLInterface* SkNativeGLContext::createGLContext() {
     HINSTANCE hInstance = (HINSTANCE)GetModuleHandle(NULL);
 
-    if (!gWC) {
-        WNDCLASS wc;
-        wc.cbClsExtra = 0;
-        wc.cbWndExtra = 0;
-        wc.hbrBackground = NULL;
-        wc.hCursor = LoadCursor(NULL, IDC_ARROW);
-        wc.hIcon = LoadIcon(NULL, IDI_APPLICATION);
-        wc.hInstance = hInstance;
-        wc.lpfnWndProc = (WNDPROC) DefWindowProc;
-        wc.lpszClassName = TEXT("Griffin");
-        wc.lpszMenuName = NULL;
-        wc.style = CS_HREDRAW | CS_VREDRAW | CS_OWNDC;
-
-        gWC = RegisterClass(&wc);
-        if (!gWC) {
-            SkDebugf("Could not register window class.\n");
-            return NULL;
-        }
-    }
-
-    if (!(fWindow = CreateWindow(TEXT("Griffin"),
-                                 TEXT("The Invisible Man"),
-                                 WS_OVERLAPPEDWINDOW,
-                                 0, 0, 1, 1,
-                                 NULL, NULL,
-                                 hInstance, NULL))) {
-        SkDebugf("Could not create window.\n");
-        return NULL;
-    }
 
     if (!(fDeviceContext = GetDC(fWindow))) {
         SkDebugf("Could not get device context.\n");
@@ -85,31 +57,7 @@ const GrGLInterface* SkNativeGLContext::createGLContext() {
         return NULL;
     }
 
-    PIXELFORMATDESCRIPTOR pfd;
-    ZeroMemory(&pfd, sizeof(pfd));
-    pfd.nSize = sizeof(pfd);
-    pfd.nVersion = 1;
-    pfd.dwFlags = PFD_SUPPORT_OPENGL;
-    pfd.iPixelType = PFD_TYPE_RGBA;
-    pfd.cColorBits = 32;
-    pfd.cDepthBits = 0;
-    pfd.cStencilBits = 0;
-    pfd.iLayerType = PFD_MAIN_PLANE;
-
-    int pixelFormat = 0;
-    if (!(pixelFormat = ChoosePixelFormat(fDeviceContext, &pfd))) {
-        SkDebugf("No matching pixel format descriptor.\n");
-        this->destroyGLContext();
-        return NULL;
-    }
-
-    if (!SetPixelFormat(fDeviceContext, pixelFormat, &pfd)) {
-        SkDebugf("Could not set the pixel format %d.\n", pixelFormat);
-        this->destroyGLContext();
-        return NULL;
-    }
-
-    if (!(fGlRenderContext = wglCreateContext(fDeviceContext))) {
+    if (!(fGlRenderContext = SkCreateWGLContext(fDeviceContext, 0, false))) {
         SkDebugf("Could not create rendering context.\n");
         this->destroyGLContext();
         return NULL;
diff --git a/utils/win/SkWGL_win.cpp b/utils/win/SkWGL_win.cpp
index 48b270d0..35153f20 100644
--- a/utils/win/SkWGL_win.cpp
+++ b/utils/win/SkWGL_win.cpp
@@ -263,3 +263,109 @@ SkWGLExtensions::SkWGLExtensions()
 
     wglMakeCurrent(prevDC, prevGLRC);
 }
+
+HGLRC SkCreateWGLContext(HDC dc, int msaaSampleCount, bool preferCoreProfile) {
+    SkWGLExtensions extensions;
+    if (!extensions.hasExtension(dc, "WGL_ARB_pixel_format")) {
+        return NULL;
+    }
+
+    HDC prevDC = wglGetCurrentDC();
+    HGLRC prevGLRC = wglGetCurrentContext();
+    PIXELFORMATDESCRIPTOR pfd;
+
+    int format = 0;
+
+    static const int iAttrs[] = {
+        SK_WGL_DRAW_TO_WINDOW, TRUE,
+        SK_WGL_DOUBLE_BUFFER, TRUE,
+        SK_WGL_ACCELERATION, SK_WGL_FULL_ACCELERATION,
+        SK_WGL_SUPPORT_OPENGL, TRUE,
+        SK_WGL_COLOR_BITS, 24,
+        SK_WGL_ALPHA_BITS, 8,
+        SK_WGL_STENCIL_BITS, 8,
+        0, 0
+    };
+
+    float fAttrs[] = {0, 0};
+
+    if (msaaSampleCount > 0 &&
+        extensions.hasExtension(dc, "WGL_ARB_multisample")) {
+        static const int kIAttrsCount = SK_ARRAY_COUNT(iAttrs);
+        int msaaIAttrs[kIAttrsCount + 6];
+        memcpy(msaaIAttrs, iAttrs, sizeof(int) * kIAttrsCount);
+        SkASSERT(0 == msaaIAttrs[kIAttrsCount - 2] &&
+                 0 == msaaIAttrs[kIAttrsCount - 1]);
+        msaaIAttrs[kIAttrsCount - 2] = SK_WGL_SAMPLE_BUFFERS;
+        msaaIAttrs[kIAttrsCount - 1] = TRUE;
+        msaaIAttrs[kIAttrsCount + 0] = SK_WGL_SAMPLES;
+        msaaIAttrs[kIAttrsCount + 1] = msaaSampleCount;
+        if (extensions.hasExtension(dc, "WGL_NV_multisample_coverage")) {
+            msaaIAttrs[kIAttrsCount + 2] = SK_WGL_COLOR_SAMPLES;
+            // We want the fewest number of color samples possible.
+            // Passing 0 gives only the formats where all samples are color
+            // samples.
+            msaaIAttrs[kIAttrsCount + 3] = 1;
+            msaaIAttrs[kIAttrsCount + 4] = 0;
+            msaaIAttrs[kIAttrsCount + 5] = 0;
+        } else {
+            msaaIAttrs[kIAttrsCount + 2] = 0;
+            msaaIAttrs[kIAttrsCount + 3] = 0;
+        }
+        unsigned int num;
+        int formats[64];
+        extensions.choosePixelFormat(dc, msaaIAttrs, fAttrs, 64, formats, &num);
+        num = min(num,64);
+        int formatToTry = extensions.selectFormat(formats,
+                                                  num,
+                                                  dc,
+                                                  msaaSampleCount);
+        DescribePixelFormat(dc, formatToTry, sizeof(pfd), &pfd);
+        if (SetPixelFormat(dc, formatToTry, &pfd)) {
+            format = formatToTry;
+        }
+    }
+
+    if (0 == format) {
+        // Either MSAA wasn't requested or creation failed
+        unsigned int num;
+        extensions.choosePixelFormat(dc, iAttrs, fAttrs, 1, &format, &num);
+        DescribePixelFormat(dc, format, sizeof(pfd), &pfd);
+        BOOL set = SetPixelFormat(dc, format, &pfd);
+        SkASSERT(TRUE == set);
+    }
+
+    HGLRC glrc = NULL;
+    if (preferCoreProfile && extensions.hasExtension(dc, "WGL_ARB_create_context")) {
+        static const int kCoreGLVersions[] = {
+            4, 3,
+            4, 2,
+            4, 1,
+            4, 0,
+            3, 3,
+            3, 2,
+        };
+        int coreProfileAttribs[] = {
+            SK_WGL_CONTEXT_MAJOR_VERSION, -1,
+            SK_WGL_CONTEXT_MINOR_VERSION, -1,
+            SK_WGL_CONTEXT_PROFILE_MASK,  SK_WGL_CONTEXT_CORE_PROFILE_BIT,
+            0,
+        };
+        for (int v = 0; v < SK_ARRAY_COUNT(kCoreGLVersions) / 2; ++v) {
+            coreProfileAttribs[1] = kCoreGLVersions[2 * v];
+            coreProfileAttribs[3] = kCoreGLVersions[2 * v + 1];
+            glrc = extensions.createContextAttribs(dc, NULL, coreProfileAttribs);
+            if (NULL != glrc) {
+                break;
+            }
+        }
+    }
+
+    if (NULL == glrc) {
+        glrc = wglCreateContext(dc);
+    }
+    SkASSERT(glrc);
+
+    wglMakeCurrent(prevDC, prevGLRC);
+    return glrc;
+}
diff --git a/views/win/SkOSWindow_win.cpp b/views/win/SkOSWindow_win.cpp
index 4eb41ce1..620bd718 100644
--- a/views/win/SkOSWindow_win.cpp
+++ b/views/win/SkOSWindow_win.cpp
@@ -323,119 +323,11 @@ void SkEvent::SignalQueueTimer(SkMSec delay)
 }
 
 #if SK_SUPPORT_GPU
-HGLRC create_gl(HWND hwnd, int msaaSampleCount) {
-
-    HDC dc = GetDC(hwnd);
-
-    SkWGLExtensions extensions;
-    if (!extensions.hasExtension(dc, "WGL_ARB_pixel_format")) {
-        return NULL;
-    }
-
-    HDC prevDC = wglGetCurrentDC();
-    HGLRC prevGLRC = wglGetCurrentContext();
-    PIXELFORMATDESCRIPTOR pfd;
-
-    int format = 0;
-
-    static const GLint iAttrs[] = {
-        SK_WGL_DRAW_TO_WINDOW, TRUE,
-        SK_WGL_DOUBLE_BUFFER, TRUE,
-        SK_WGL_ACCELERATION, SK_WGL_FULL_ACCELERATION,
-        SK_WGL_SUPPORT_OPENGL, TRUE,
-        SK_WGL_COLOR_BITS, 24,
-        SK_WGL_ALPHA_BITS, 8,
-        SK_WGL_STENCIL_BITS, 8,
-        0, 0
-    };
-
-    GLfloat fAttrs[] = {0, 0};
-
-    if (msaaSampleCount > 0 &&
-        extensions.hasExtension(dc, "WGL_ARB_multisample")) {
-        static const int kIAttrsCount = SK_ARRAY_COUNT(iAttrs);
-        GLint msaaIAttrs[kIAttrsCount + 6];
-        memcpy(msaaIAttrs, iAttrs, sizeof(GLint) * kIAttrsCount);
-        SkASSERT(0 == msaaIAttrs[kIAttrsCount - 2] &&
-                 0 == msaaIAttrs[kIAttrsCount - 1]);
-        msaaIAttrs[kIAttrsCount - 2] = SK_WGL_SAMPLE_BUFFERS;
-        msaaIAttrs[kIAttrsCount - 1] = TRUE;
-        msaaIAttrs[kIAttrsCount + 0] = SK_WGL_SAMPLES;
-        msaaIAttrs[kIAttrsCount + 1] = msaaSampleCount;
-        if (extensions.hasExtension(dc, "WGL_NV_multisample_coverage")) {
-            msaaIAttrs[kIAttrsCount + 2] = SK_WGL_COLOR_SAMPLES;
-            // We want the fewest number of color samples possible.
-            // Passing 0 gives only the formats where all samples are color
-            // samples.
-            msaaIAttrs[kIAttrsCount + 3] = 1;
-            msaaIAttrs[kIAttrsCount + 4] = 0;
-            msaaIAttrs[kIAttrsCount + 5] = 0;
-        } else {
-            msaaIAttrs[kIAttrsCount + 2] = 0;
-            msaaIAttrs[kIAttrsCount + 3] = 0;
-        }
-        GLuint num;
-        int formats[64];
-        extensions.choosePixelFormat(dc, msaaIAttrs, fAttrs, 64, formats, &num);
-        num = min(num,64);
-        int formatToTry = extensions.selectFormat(formats,
-                                                  num,
-                                                  dc,
-                                                  msaaSampleCount);
-        DescribePixelFormat(dc, formatToTry, sizeof(pfd), &pfd);
-        if (SetPixelFormat(dc, formatToTry, &pfd)) {
-            format = formatToTry;
-        }
-    }
-
-    if (0 == format) {
-        GLuint num;
-        extensions.choosePixelFormat(dc, iAttrs, fAttrs, 1, &format, &num);
-        DescribePixelFormat(dc, format, sizeof(pfd), &pfd);
-        BOOL set = SetPixelFormat(dc, format, &pfd);
-        SkASSERT(TRUE == set);
-    }
-
-    HGLRC glrc = NULL;
-#if 0 // Change to 1 to attempt to create a core profile GL context of version 4.3 or lower
-    if (extensions.hasExtension(dc, "WGL_ARB_create_context")) {
-        static const GLint kCoreGLVersions[] = {
-            4, 3,
-            4, 2,
-            4, 1,
-            4, 0,
-            3, 3,
-            3, 2,
-        };
-        GLint coreProfileAttribs[] = {
-            SK_WGL_CONTEXT_MAJOR_VERSION, -1,
-            SK_WGL_CONTEXT_MINOR_VERSION, -1,
-            SK_WGL_CONTEXT_PROFILE_MASK,  SK_WGL_CONTEXT_CORE_PROFILE_BIT,
-            0,
-        };
-        for (int v = 0; v < SK_ARRAY_COUNT(kCoreGLVersions) / 2; ++v) {
-            coreProfileAttribs[1] = kCoreGLVersions[2 * v];
-            coreProfileAttribs[3] = kCoreGLVersions[2 * v + 1];
-            glrc = extensions.createContextAttribs(dc, NULL, coreProfileAttribs);
-            if (NULL != glrc) {
-                break;
-            }
-        }
-    }
-#endif
-
-    if (NULL == glrc) {
-        glrc = wglCreateContext(dc);
-    }
-    SkASSERT(glrc);
-
-    wglMakeCurrent(prevDC, prevGLRC);
-    return glrc;
-}
 
 bool SkOSWindow::attachGL(int msaaSampleCount) {
+    HDC dc = GetDC((HWND)fHWND);
     if (NULL == fHGLRC) {
-        fHGLRC = create_gl((HWND)fHWND, msaaSampleCount);
+        fHGLRC = SkCreateWGLContext(dc, msaaSampleCount, false);
         if (NULL == fHGLRC) {
             return false;
         }
@@ -444,7 +336,7 @@ bool SkOSWindow::attachGL(int msaaSampleCount) {
         glStencilMask(0xffffffff);
         glClear(GL_STENCIL_BUFFER_BIT | GL_COLOR_BUFFER_BIT);
     }
-    if (wglMakeCurrent(GetDC((HWND)fHWND), (HGLRC)fHGLRC)) {
+    if (wglMakeCurrent(dc, (HGLRC)fHGLRC)) {
         glViewport(0, 0, SkScalarRound(this->width()),
                    SkScalarRound(this->height()));
         return true;