michael@0: 
michael@0: /*
michael@0:  * Copyright 2011 Google Inc.
michael@0:  *
michael@0:  * Use of this source code is governed by a BSD-style license that can be
michael@0:  * found in the LICENSE file.
michael@0:  */
michael@0: 
michael@0: #include <GL/osmesa.h>
michael@0: 
michael@0: #include "gl/SkMesaGLContext.h"
michael@0: #include "gl/GrGLDefines.h"
michael@0: 
michael@0: SkMesaGLContext::AutoContextRestore::AutoContextRestore() {
michael@0:     fOldContext = (Context)OSMesaGetCurrentContext();
michael@0:     if (NULL != (OSMesaContext)fOldContext) {
michael@0:         OSMesaGetColorBuffer((OSMesaContext)fOldContext,
michael@0:                               &fOldWidth, &fOldHeight,
michael@0:                               &fOldFormat, &fOldImage);
michael@0:     }
michael@0: }
michael@0: 
michael@0: SkMesaGLContext::AutoContextRestore::~AutoContextRestore() {
michael@0:     if (NULL != (OSMesaContext)fOldContext) {
michael@0:         OSMesaMakeCurrent((OSMesaContext)fOldContext, fOldImage,
michael@0:                           fOldFormat, fOldWidth, fOldHeight);
michael@0:     }
michael@0: }
michael@0: 
michael@0: ///////////////////////////////////////////////////////////////////////////////
michael@0: 
michael@0: SkMesaGLContext::SkMesaGLContext()
michael@0:     : fContext(static_cast<Context>(NULL))
michael@0:     , fImage(NULL) {
michael@0:     GR_STATIC_ASSERT(sizeof(Context) == sizeof(OSMesaContext));
michael@0: }
michael@0: 
michael@0: SkMesaGLContext::~SkMesaGLContext() {
michael@0:     this->destroyGLContext();
michael@0: }
michael@0: 
michael@0: void SkMesaGLContext::destroyGLContext() {
michael@0:     if (fImage) {
michael@0:         sk_free(fImage);
michael@0:         fImage = NULL;
michael@0:     }
michael@0: 
michael@0:     if (fContext) {
michael@0:         OSMesaDestroyContext((OSMesaContext)fContext);
michael@0:         fContext = static_cast<Context>(NULL);
michael@0:     }
michael@0: }
michael@0: 
michael@0: static const GrGLint gBOGUS_SIZE = 16;
michael@0: 
michael@0: const GrGLInterface* SkMesaGLContext::createGLContext() {
michael@0:     /* Create an RGBA-mode context */
michael@0: #if OSMESA_MAJOR_VERSION * 100 + OSMESA_MINOR_VERSION >= 305
michael@0:     /* specify Z, stencil, accum sizes */
michael@0:     fContext = (Context)OSMesaCreateContextExt(OSMESA_BGRA, 0, 0, 0, NULL);
michael@0: #else
michael@0:     fContext = (Context)OSMesaCreateContext(OSMESA_BGRA, NULL);
michael@0: #endif
michael@0:     if (!fContext) {
michael@0:         SkDebugf("OSMesaCreateContext failed!\n");
michael@0:         this->destroyGLContext();
michael@0:         return NULL;
michael@0:     }
michael@0:     // Allocate the image buffer
michael@0:     fImage = (GrGLubyte *) sk_malloc_throw(gBOGUS_SIZE * gBOGUS_SIZE *
michael@0:                                            4 * sizeof(GrGLubyte));
michael@0:     if (!fImage) {
michael@0:         SkDebugf("Alloc image buffer failed!\n");
michael@0:         this->destroyGLContext();
michael@0:         return NULL;
michael@0:     }
michael@0: 
michael@0:     // Bind the buffer to the context and make it current
michael@0:     if (!OSMesaMakeCurrent((OSMesaContext)fContext,
michael@0:                            fImage,
michael@0:                            GR_GL_UNSIGNED_BYTE,
michael@0:                            gBOGUS_SIZE,
michael@0:                            gBOGUS_SIZE)) {
michael@0:         SkDebugf("OSMesaMakeCurrent failed!\n");
michael@0:         this->destroyGLContext();
michael@0:         return NULL;
michael@0:     }
michael@0: 
michael@0:     const GrGLInterface* interface = GrGLCreateMesaInterface();
michael@0:     if (!interface) {
michael@0:         SkDebugf("Could not create GL interface!\n");
michael@0:         this->destroyGLContext();
michael@0:         return NULL;
michael@0:     }
michael@0:     return interface;
michael@0: 
michael@0: }
michael@0: 
michael@0: void SkMesaGLContext::makeCurrent() const {
michael@0:     if (fContext) {
michael@0:         if (!OSMesaMakeCurrent((OSMesaContext)fContext, fImage,
michael@0:                                GR_GL_UNSIGNED_BYTE, gBOGUS_SIZE, gBOGUS_SIZE)) {
michael@0:             SkDebugf("Could not make MESA context current.");
michael@0:         }
michael@0:     }
michael@0: }
michael@0: 
michael@0: void SkMesaGLContext::swapBuffers() const { }