ui/gl/gl_surface_osmesa.cc

   1 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #include "base/logging.h"
   6 #include "ui/gl/gl_bindings.h"
   7 #include "ui/gl/gl_context.h"
   8 #include "ui/gl/gl_surface_osmesa.h"
   9 #include "ui/gl/scoped_make_current.h"
  10
  11 namespace gfx {
  12
  13 GLSurfaceOSMesa::GLSurfaceOSMesa(unsigned format, const gfx::Size& size)
  14     : format_(format),
  15       size_(size) {
  16 }
  17
  18 bool GLSurfaceOSMesa::Initialize() {
  19   return Resize(size_);
  20 }
  21
  22 void GLSurfaceOSMesa::Destroy() {
  23   buffer_.reset();
  24 }
  25
  26 bool GLSurfaceOSMesa::Resize(const gfx::Size& new_size) {
  27   scoped_ptr<ui::ScopedMakeCurrent> scoped_make_current;
  28   GLContext* current_context = GLContext::GetCurrent();
  29   bool was_current =
  30       current_context && current_context->IsCurrent(this);
  31   if (was_current) {
  32     scoped_make_current.reset(
  33         new ui::ScopedMakeCurrent(current_context, this));
  34     current_context->ReleaseCurrent(this);
  35   }
  36
  37   // Preserve the old buffer.
  38   scoped_ptr<int32[]> old_buffer(buffer_.release());
  39
  40   // Allocate a new one.
  41   buffer_.reset(new int32[new_size.GetArea()]);
  42   memset(buffer_.get(), 0, new_size.GetArea() * sizeof(buffer_[0]));
  43
  44   // Copy the old back buffer into the new buffer.
  45   if (old_buffer.get()) {
  46     int copy_width = std::min(size_.width(), new_size.width());
  47     int copy_height = std::min(size_.height(), new_size.height());
  48     for (int y = 0; y < copy_height; ++y) {
  49       for (int x = 0; x < copy_width; ++x) {
  50         buffer_[y * new_size.width() + x] = old_buffer[y * size_.width() + x];
  51       }
  52     }
  53   }
  54
  55   size_ = new_size;
  56
  57   return true;
  58 }
  59
  60 bool GLSurfaceOSMesa::IsOffscreen() {
  61   return true;
  62 }
  63
  64 bool GLSurfaceOSMesa::SwapBuffers() {
  65   NOTREACHED() << "Should not call SwapBuffers on an GLSurfaceOSMesa.";
  66   return false;
  67 }
  68
  69 gfx::Size GLSurfaceOSMesa::GetSize() {
  70   return size_;
  71 }
  72
  73 void* GLSurfaceOSMesa::GetHandle() {
  74   return buffer_.get();
  75 }
  76
  77 unsigned GLSurfaceOSMesa::GetFormat() {
  78   return format_;
  79 }
  80
  81 GLSurfaceOSMesa::~GLSurfaceOSMesa() {
  82   Destroy();
  83 }
  84
  85 }  // namespace gfx