1
2/*
3 * Copyright 2011 Google Inc.
4 *
5 * Use of this source code is governed by a BSD-style license that can be
6 * found in the LICENSE file.
7 */
8
9#include "gl/SkNativeGLContext.h"
10
11#define WIN32_LEAN_AND_MEAN
12#include <Windows.h>
13
14SkNativeGLContext::AutoContextRestore::AutoContextRestore() {
15    fOldHGLRC = wglGetCurrentContext();
16    fOldHDC = wglGetCurrentDC();
17}
18
19SkNativeGLContext::AutoContextRestore::~AutoContextRestore() {
20    wglMakeCurrent(fOldHDC, fOldHGLRC);
21}
22
23///////////////////////////////////////////////////////////////////////////////
24
25ATOM SkNativeGLContext::gWC = 0;
26
27SkNativeGLContext::SkNativeGLContext()
28    : fWindow(NULL)
29    , fDeviceContext(NULL)
30    , fGlRenderContext(0) {
31}
32
33SkNativeGLContext::~SkNativeGLContext() {
34    this->destroyGLContext();
35}
36
37void SkNativeGLContext::destroyGLContext() {
38    if (fGlRenderContext) {
39        wglDeleteContext(fGlRenderContext);
40    }
41    if (fWindow && fDeviceContext) {
42        ReleaseDC(fWindow, fDeviceContext);
43    }
44    if (fWindow) {
45        DestroyWindow(fWindow);
46    }
47}
48
49const GrGLInterface* SkNativeGLContext::createGLContext() {
50    HINSTANCE hInstance = (HINSTANCE)GetModuleHandle(NULL);
51
52    if (!gWC) {
53        WNDCLASS wc;
54        wc.cbClsExtra = 0;
55        wc.cbWndExtra = 0;
56        wc.hbrBackground = NULL;
57        wc.hCursor = LoadCursor(NULL, IDC_ARROW);
58        wc.hIcon = LoadIcon(NULL, IDI_APPLICATION);
59        wc.hInstance = hInstance;
60        wc.lpfnWndProc = (WNDPROC) DefWindowProc;
61        wc.lpszClassName = TEXT("Griffin");
62        wc.lpszMenuName = NULL;
63        wc.style = CS_HREDRAW | CS_VREDRAW | CS_OWNDC;
64
65        gWC = RegisterClass(&wc);
66        if (!gWC) {
67            SkDebugf("Could not register window class.\n");
68            return NULL;
69        }
70    }
71
72    if (!(fWindow = CreateWindow(TEXT("Griffin"),
73                                 TEXT("The Invisible Man"),
74                                 WS_OVERLAPPEDWINDOW,
75                                 0, 0, 1, 1,
76                                 NULL, NULL,
77                                 hInstance, NULL))) {
78        SkDebugf("Could not create window.\n");
79        return NULL;
80    }
81
82    if (!(fDeviceContext = GetDC(fWindow))) {
83        SkDebugf("Could not get device context.\n");
84        this->destroyGLContext();
85        return NULL;
86    }
87
88    PIXELFORMATDESCRIPTOR pfd;
89    ZeroMemory(&pfd, sizeof(pfd));
90    pfd.nSize = sizeof(pfd);
91    pfd.nVersion = 1;
92    pfd.dwFlags = PFD_SUPPORT_OPENGL;
93    pfd.iPixelType = PFD_TYPE_RGBA;
94    pfd.cColorBits = 32;
95    pfd.cDepthBits = 0;
96    pfd.cStencilBits = 0;
97    pfd.iLayerType = PFD_MAIN_PLANE;
98
99    int pixelFormat = 0;
100    if (!(pixelFormat = ChoosePixelFormat(fDeviceContext, &pfd))) {
101        SkDebugf("No matching pixel format descriptor.\n");
102        this->destroyGLContext();
103        return NULL;
104    }
105
106    if (!SetPixelFormat(fDeviceContext, pixelFormat, &pfd)) {
107        SkDebugf("Could not set the pixel format %d.\n", pixelFormat);
108        this->destroyGLContext();
109        return NULL;
110    }
111
112    if (!(fGlRenderContext = wglCreateContext(fDeviceContext))) {
113        SkDebugf("Could not create rendering context.\n");
114        this->destroyGLContext();
115        return NULL;
116    }
117
118    if (!(wglMakeCurrent(fDeviceContext, fGlRenderContext))) {
119        SkDebugf("Could not set the context.\n");
120        this->destroyGLContext();
121        return NULL;
122    }
123    const GrGLInterface* interface = GrGLCreateNativeInterface();
124    if (NULL == interface) {
125        SkDebugf("Could not create GL interface.\n");
126        this->destroyGLContext();
127        return NULL;
128    }
129
130    return interface;
131}
132
133void SkNativeGLContext::makeCurrent() const {
134    if (!wglMakeCurrent(fDeviceContext, fGlRenderContext)) {
135        SkDebugf("Could not create rendering context.\n");
136    }
137}
138