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/osmesa.h>
10 
11 #include "gl/mesa/SkMesaGLContext.h"
12 #include "gl/GrGLDefines.h"
13 
14 static const GrGLint gBOGUS_SIZE = 16;
15 
SkMesaGLContext()16 SkMesaGLContext::SkMesaGLContext()
17     : fContext(static_cast<Context>(NULL))
18     , fImage(NULL) {
19     GR_STATIC_ASSERT(sizeof(Context) == sizeof(OSMesaContext));
20 
21     /* Create an RGBA-mode context */
22 #if OSMESA_MAJOR_VERSION * 100 + OSMESA_MINOR_VERSION >= 305
23     /* specify Z, stencil, accum sizes */
24     fContext = (Context)OSMesaCreateContextExt(OSMESA_BGRA, 0, 0, 0, NULL);
25 #else
26     fContext = (Context)OSMesaCreateContext(OSMESA_BGRA, NULL);
27 #endif
28     if (!fContext) {
29         SkDebugf("OSMesaCreateContext failed!\n");
30         this->destroyGLContext();
31         return;
32     }
33     // Allocate the image buffer
34     fImage = (GrGLubyte *) sk_malloc_throw(gBOGUS_SIZE * gBOGUS_SIZE *
35                                            4 * sizeof(GrGLubyte));
36     if (!fImage) {
37         SkDebugf("Alloc image buffer failed!\n");
38         this->destroyGLContext();
39         return;
40     }
41 
42     // Bind the buffer to the context and make it current
43     if (!OSMesaMakeCurrent((OSMesaContext)fContext,
44                            fImage,
45                            GR_GL_UNSIGNED_BYTE,
46                            gBOGUS_SIZE,
47                            gBOGUS_SIZE)) {
48         SkDebugf("OSMesaMakeCurrent failed!\n");
49         this->destroyGLContext();
50         return;
51     }
52 
53     fGL.reset(GrGLCreateMesaInterface());
54     if (NULL == fGL.get()) {
55         SkDebugf("Could not create GL interface!\n");
56         this->destroyGLContext();
57         return;
58     }
59 
60     if (!fGL->validate()) {
61         SkDebugf("Could not validate GL interface!\n");
62         this->destroyGLContext();
63         return;
64     }
65 }
66 
~SkMesaGLContext()67 SkMesaGLContext::~SkMesaGLContext() {
68     this->destroyGLContext();
69 }
70 
destroyGLContext()71 void SkMesaGLContext::destroyGLContext() {
72     fGL.reset(NULL);
73     if (fImage) {
74         sk_free(fImage);
75         fImage = NULL;
76     }
77 
78     if (fContext) {
79         OSMesaDestroyContext((OSMesaContext)fContext);
80         fContext = static_cast<Context>(NULL);
81     }
82 }
83 
84 
85 
makeCurrent() const86 void SkMesaGLContext::makeCurrent() const {
87     if (fContext) {
88         if (!OSMesaMakeCurrent((OSMesaContext)fContext, fImage,
89                                GR_GL_UNSIGNED_BYTE, gBOGUS_SIZE, gBOGUS_SIZE)) {
90             SkDebugf("Could not make MESA context current.");
91         }
92     }
93 }
94 
swapBuffers() const95 void SkMesaGLContext::swapBuffers() const { }
96