Refactor GL surface format handling

ui/gl/gl_surface_format.cc

Index: ui/gl/gl_surface_format.cc
diff --git a/ui/gl/gl_surface_format.cc b/ui/gl/gl_surface_format.cc
new file mode 100644
index 0000000000000000000000000000000000000000..b57dbdb847e9dddb773d6ccc82506dfacd926aa3
--- /dev/null
+++ b/ui/gl/gl_surface_format.cc
@@ -0,0 +1,126 @@
+// Copyright 2017 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "base/logging.h"
+#include "ui/gl/gl_surface_format.h"
+
+namespace gl {
+
+GLSurfaceFormat::GLSurfaceFormat() {
+}
+
+GLSurfaceFormat::GLSurfaceFormat(SurfacePixelLayout layout) {
+  is_default_ = false;
+  pixel_layout_ = layout;
+}
+
+GLSurfaceFormat::GLSurfaceFormat(const GLSurfaceFormat& other) = default;
+
+GLSurfaceFormat::~GLSurfaceFormat() {
+}
+
+bool GLSurfaceFormat::IsSurfaceless() {
+  return is_surfaceless_;
+}
+
+GLSurfaceFormat::SurfacePixelLayout GLSurfaceFormat::GetPixelLayout() {
+  return pixel_layout_;
+}
+
+void GLSurfaceFormat::SetDefaultPixelLayout(SurfacePixelLayout layout) {
+  if (pixel_layout_ == PIXEL_LAYOUT_DONT_CARE &&
+      layout != PIXEL_LAYOUT_DONT_CARE) {
+    pixel_layout_ = layout;
+    is_default_ = false;
+  }
+}
+
+void GLSurfaceFormat::SetRGB565() {
+  red_bits_ = blue_bits_ = 5;
+  green_bits_ = 6;
+  alpha_bits_ = 0;
+  is_default_ = false;
+}
+
+void GLSurfaceFormat::SetIsSurfaceless() {
+  is_surfaceless_ = true;
+  is_default_ = false;
+}
+
+static int GetValue(int num, int default_value) {
+  return num == -1 ? default_value : num;
+}
+
+static int GetBitSize(int num) {
+  return GetValue(num, 8);
+}
+
+
+bool GLSurfaceFormat::IsDefault() {
+  return is_default_;
+}
+
+bool GLSurfaceFormat::IsCompatible(GLSurfaceFormat other) {
+  if (IsDefault() && other.IsDefault()) return true;
+
+  if (GetBitSize(red_bits_) == GetBitSize(other.red_bits_) &&
+      GetBitSize(green_bits_) == GetBitSize(other.green_bits_) &&
+      GetBitSize(blue_bits_) == GetBitSize(other.blue_bits_) &&
+      GetBitSize(alpha_bits_) == GetBitSize(other.alpha_bits_) &&
+      GetValue(stencil_bits_, 8) == GetValue(other.stencil_bits_, 8) &&
+      GetValue(depth_bits_, 24) == GetValue(other.depth_bits_, 24) &&
+      GetValue(samples_, 0) == GetValue(other.samples_, 0) &&
+      is_surfaceless_ == other.is_surfaceless_ &&
+      pixel_layout_ == other.pixel_layout_) {
+    return true;
+  }
+  return false;
+}
+
+void GLSurfaceFormat::SetDepthBits(int bits) {
+  if (bits != -1) {
+    depth_bits_ = bits;
+    is_default_ = false;
+  }
+}
+
+int GLSurfaceFormat::GetDepthBits() {
+  return depth_bits_;
+}
+
+void GLSurfaceFormat::SetStencilBits(int bits) {
+  if (bits != -1) {
+    stencil_bits_ = bits;
+    is_default_ = false;
+  }
+}
+
+int GLSurfaceFormat::GetStencilBits() {
+  return stencil_bits_;
+}
+
+void GLSurfaceFormat::SetSamples(int num) {
+  if (num != -1) {
+    samples_ = num;
+    is_default_ = false;
+  }
+}
+
+int GLSurfaceFormat::GetSamples() {
+  return samples_;
+}
+
+int GLSurfaceFormat::GetBufferSize() {
+  int bits = GetBitSize(red_bits_) + GetBitSize(green_bits_) +
+      GetBitSize(blue_bits_) + GetBitSize(alpha_bits_);
+  if (bits <= 16) {
+    return 16;
+  } else if (bits <= 32) {
+    return 32;
+  }
+  NOTREACHED();
+  return 64;
+}
+
+}  // namespace gl