mirror of
https://github.com/flutter/flutter.git
synced 2026-02-20 02:29:02 +08:00
41 lines
1.3 KiB
C++
41 lines
1.3 KiB
C++
// Copyright (c) 2009 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.
|
|
|
|
// This file contains a helper template class used to access bit fields in
|
|
// unsigned int_ts.
|
|
|
|
#ifndef GPU_COMMAND_BUFFER_COMMON_BITFIELD_HELPERS_H_
|
|
#define GPU_COMMAND_BUFFER_COMMON_BITFIELD_HELPERS_H_
|
|
|
|
namespace gpu {
|
|
|
|
// Bitfield template class, used to access bit fields in unsigned int_ts.
|
|
template<int shift, int length> class BitField {
|
|
public:
|
|
static const unsigned int kShift = shift;
|
|
static const unsigned int kLength = length;
|
|
// the following is really (1<<length)-1 but also work for length == 32
|
|
// without compiler warning.
|
|
static const unsigned int kMask = 1U + ((1U << (length-1)) - 1U) * 2U;
|
|
|
|
// Gets the value contained in this field.
|
|
static unsigned int Get(unsigned int container) {
|
|
return (container >> kShift) & kMask;
|
|
}
|
|
|
|
// Makes a value that can be or-ed into this field.
|
|
static unsigned int MakeValue(unsigned int value) {
|
|
return (value & kMask) << kShift;
|
|
}
|
|
|
|
// Changes the value of this field.
|
|
static void Set(unsigned int *container, unsigned int field_value) {
|
|
*container = (*container & ~(kMask << kShift)) | MakeValue(field_value);
|
|
}
|
|
};
|
|
|
|
} // namespace gpu
|
|
|
|
#endif // GPU_COMMAND_BUFFER_COMMON_BITFIELD_HELPERS_H_
|