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>(0))
18     , fImage(nullptr) {
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, nullptr);
25 #else
26     fContext = (Context)OSMesaCreateContext(OSMESA_BGRA, nullptr);
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     SkAutoTUnref<const GrGLInterface> gl(GrGLCreateMesaInterface());
54     if (nullptr == gl.get()) {
55         SkDebugf("Could not create GL interface!\n");
56         this->destroyGLContext();
57         return;
58     }
59 
60     if (!gl->validate()) {
61         SkDebugf("Could not validate GL interface!\n");
62         this->destroyGLContext();
63         return;
64     }
65 
66     this->init(gl.detach());
67 }
68 
~SkMesaGLContext()69 SkMesaGLContext::~SkMesaGLContext() {
70     this->teardown();
71     this->destroyGLContext();
72 }
73 
destroyGLContext()74 void SkMesaGLContext::destroyGLContext() {
75     if (fImage) {
76         sk_free(fImage);
77         fImage = nullptr;
78     }
79 
80     if (fContext) {
81         OSMesaDestroyContext((OSMesaContext)fContext);
82         fContext = static_cast<Context>(0);
83     }
84 }
85 
86 
87 
onPlatformMakeCurrent() const88 void SkMesaGLContext::onPlatformMakeCurrent() const {
89     if (fContext) {
90         if (!OSMesaMakeCurrent((OSMesaContext)fContext, fImage,
91                                GR_GL_UNSIGNED_BYTE, gBOGUS_SIZE, gBOGUS_SIZE)) {
92             SkDebugf("Could not make MESA context current.");
93         }
94     }
95 }
96 
onPlatformSwapBuffers() const97 void SkMesaGLContext::onPlatformSwapBuffers() const { }
98 
onPlatformGetProcAddress(const char * procName) const99 GrGLFuncPtr SkMesaGLContext::onPlatformGetProcAddress(const char* procName) const {
100     return OSMesaGetProcAddress(procName);
101 }
102