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 "third_party/mesa/src/include/GL/osmesa.h"
7#include "ui/gl/gl_bindings.h"
8#include "ui/gl/gl_context.h"
9#include "ui/gl/gl_surface_osmesa.h"
10#include "ui/gl/scoped_make_current.h"
11
12namespace gfx {
13
14GLSurfaceOSMesa::GLSurfaceOSMesa(OSMesaSurfaceFormat format,
15                                 const gfx::Size& size)
16    : size_(size) {
17  switch (format) {
18    case OSMesaSurfaceFormatBGRA:
19      format_ = OSMESA_BGRA;
20      break;
21    case OSMesaSurfaceFormatRGBA:
22      format_ = OSMESA_RGBA;
23      break;
24  }
25  // Implementations of OSMesa surface do not support having a 0 size. In such
26  // cases use a (1, 1) surface.
27  if (size_.GetArea() == 0)
28    size_.SetSize(1, 1);
29}
30
31bool GLSurfaceOSMesa::Initialize() {
32  return Resize(size_);
33}
34
35void GLSurfaceOSMesa::Destroy() {
36  buffer_.reset();
37}
38
39bool GLSurfaceOSMesa::Resize(const gfx::Size& new_size) {
40  scoped_ptr<ui::ScopedMakeCurrent> scoped_make_current;
41  GLContext* current_context = GLContext::GetCurrent();
42  bool was_current =
43      current_context && current_context->IsCurrent(this);
44  if (was_current) {
45    scoped_make_current.reset(
46        new ui::ScopedMakeCurrent(current_context, this));
47    current_context->ReleaseCurrent(this);
48  }
49
50  // Preserve the old buffer.
51  scoped_ptr<int32[]> old_buffer(buffer_.release());
52
53  // Allocate a new one.
54  buffer_.reset(new int32[new_size.GetArea()]);
55  memset(buffer_.get(), 0, new_size.GetArea() * sizeof(buffer_[0]));
56
57  // Copy the old back buffer into the new buffer.
58  if (old_buffer.get()) {
59    int copy_width = std::min(size_.width(), new_size.width());
60    int copy_height = std::min(size_.height(), new_size.height());
61    for (int y = 0; y < copy_height; ++y) {
62      for (int x = 0; x < copy_width; ++x) {
63        buffer_[y * new_size.width() + x] = old_buffer[y * size_.width() + x];
64      }
65    }
66  }
67
68  size_ = new_size;
69
70  return true;
71}
72
73bool GLSurfaceOSMesa::IsOffscreen() {
74  return true;
75}
76
77bool GLSurfaceOSMesa::SwapBuffers() {
78  NOTREACHED() << "Should not call SwapBuffers on an GLSurfaceOSMesa.";
79  return false;
80}
81
82gfx::Size GLSurfaceOSMesa::GetSize() {
83  return size_;
84}
85
86void* GLSurfaceOSMesa::GetHandle() {
87  return buffer_.get();
88}
89
90unsigned GLSurfaceOSMesa::GetFormat() {
91  return format_;
92}
93
94GLSurfaceOSMesa::~GLSurfaceOSMesa() {
95  Destroy();
96}
97
98bool GLSurfaceOSMesaHeadless::IsOffscreen() { return false; }
99
100bool GLSurfaceOSMesaHeadless::SwapBuffers() { return true; }
101
102GLSurfaceOSMesaHeadless::GLSurfaceOSMesaHeadless()
103    : GLSurfaceOSMesa(OSMesaSurfaceFormatBGRA, gfx::Size(1, 1)) {
104}
105
106GLSurfaceOSMesaHeadless::~GLSurfaceOSMesaHeadless() { Destroy(); }
107
108}  // namespace gfx
109