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 "base/numerics/safe_math.h"
   7 #include "third_party/mesa/src/include/GL/osmesa.h"
   8 #include "ui/gl/gl_bindings.h"
   9 #include "ui/gl/gl_context.h"
  10 #include "ui/gl/gl_surface_osmesa.h"
  11 #include "ui/gl/scoped_make_current.h"
  12
  13 namespace gfx {
  14
  15 GLSurfaceOSMesa::GLSurfaceOSMesa(OSMesaSurfaceFormat format,
  16                                  const gfx::Size& size)
  17     : size_(size) {
  18   switch (format) {
  19     case OSMesaSurfaceFormatBGRA:
  20       format_ = OSMESA_BGRA;
  21       break;
  22     case OSMesaSurfaceFormatRGBA:
  23       format_ = OSMESA_RGBA;
  24       break;
  25   }
  26   // Implementations of OSMesa surface do not support having a 0 size. In such
  27   // cases use a (1, 1) surface.
  28   if (size_.GetArea() == 0)
  29     size_.SetSize(1, 1);
  30 }
  31
  32 bool GLSurfaceOSMesa::Initialize() {
  33   return Resize(size_);
  34 }
  35
  36 void GLSurfaceOSMesa::Destroy() {
  37   buffer_.reset();
  38 }
  39
  40 bool GLSurfaceOSMesa::Resize(const gfx::Size& new_size) {
  41   scoped_ptr<ui::ScopedMakeCurrent> scoped_make_current;
  42   GLContext* current_context = GLContext::GetCurrent();
  43   bool was_current =
  44       current_context && current_context->IsCurrent(this);
  45   if (was_current) {
  46     scoped_make_current.reset(
  47         new ui::ScopedMakeCurrent(current_context, this));
  48     current_context->ReleaseCurrent(this);
  49   }
  50
  51   // Preserve the old buffer.
  52   scoped_ptr<int32[]> old_buffer(buffer_.release());
  53
  54   base::CheckedNumeric<int> checked_size = sizeof(buffer_[0]);
  55   checked_size *= new_size.width();
  56   checked_size *= new_size.height();
  57   if (!checked_size.IsValid())
  58     return false;
  59
  60   // Allocate a new one.
  61   buffer_.reset(new int32[new_size.GetArea()]);
  62   if (!buffer_.get())
  63     return false;
  64
  65   memset(buffer_.get(), 0, new_size.GetArea() * sizeof(buffer_[0]));
  66
  67   // Copy the old back buffer into the new buffer.
  68   if (old_buffer.get()) {
  69     int copy_width = std::min(size_.width(), new_size.width());
  70     int copy_height = std::min(size_.height(), new_size.height());
  71     for (int y = 0; y < copy_height; ++y) {
  72       for (int x = 0; x < copy_width; ++x) {
  73         buffer_[y * new_size.width() + x] = old_buffer[y * size_.width() + x];
  74       }
  75     }
  76   }
  77
  78   size_ = new_size;
  79
  80   return true;
  81 }
  82
  83 bool GLSurfaceOSMesa::IsOffscreen() {
  84   return true;
  85 }
  86
  87 bool GLSurfaceOSMesa::SwapBuffers() {
  88   NOTREACHED() << "Should not call SwapBuffers on an GLSurfaceOSMesa.";
  89   return false;
  90 }
  91
  92 gfx::Size GLSurfaceOSMesa::GetSize() {
  93   return size_;
  94 }
  95
  96 void* GLSurfaceOSMesa::GetHandle() {
  97   return buffer_.get();
  98 }
  99
 100 unsigned GLSurfaceOSMesa::GetFormat() {
 101   return format_;
 102 }
 103
 104 GLSurfaceOSMesa::~GLSurfaceOSMesa() {
 105   Destroy();
 106 }
 107
 108 bool GLSurfaceOSMesaHeadless::IsOffscreen() { return false; }
 109
 110 bool GLSurfaceOSMesaHeadless::SwapBuffers() { return true; }
 111
 112 GLSurfaceOSMesaHeadless::GLSurfaceOSMesaHeadless()
 113     : GLSurfaceOSMesa(OSMesaSurfaceFormatBGRA, gfx::Size(1, 1)) {
 114 }
 115
 116 GLSurfaceOSMesaHeadless::~GLSurfaceOSMesaHeadless() { Destroy(); }
 117
 118 }  // namespace gfx