skia2/include/core/SkPackBits.h
reed@android.com 8a1c16ff38 grab from latest android
git-svn-id: http://skia.googlecode.com/svn/trunk@27 2bbb7eff-a529-9590-31e7-b0007b416f81
2008-12-17 15:59:43 +00:00

87 lines
3.7 KiB
C++

/*
* Copyright (C) 2008 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#ifndef SkPackBits_DEFINED
#define SkPackBits_DEFINED
#include "SkTypes.h"
class SkPackBits {
public:
/** Given the number of 16bit values that will be passed to Pack16,
returns the worst-case size needed for the dst[] buffer.
*/
static size_t ComputeMaxSize16(int count);
/** Given the number of 8bit values that will be passed to Pack8,
returns the worst-case size needed for the dst[] buffer.
*/
static size_t ComputeMaxSize8(int count);
/** Write the src array into a packed format. The packing process may end
up writing more bytes than it read, so dst[] must be large enough.
@param src Input array of 16bit values
@param count Number of entries in src[]
@param dst Buffer (allocated by caller) to write the packed data
into
@return the number of bytes written to dst[]
*/
static size_t Pack16(const uint16_t src[], int count, uint8_t dst[]);
/** Write the src array into a packed format. The packing process may end
up writing more bytes than it read, so dst[] must be large enough.
@param src Input array of 8bit values
@param count Number of entries in src[]
@param dst Buffer (allocated by caller) to write the packed data
into
@return the number of bytes written to dst[]
*/
static size_t Pack8(const uint8_t src[], int count, uint8_t dst[]);
/** Unpack the data in src[], and expand it into dst[]. The src[] data was
written by a previous call to Pack16.
@param src Input data to unpack, previously created by Pack16.
@param srcSize Number of bytes of src to unpack
@param dst Buffer (allocated by caller) to expand the src[] into.
@return the number of dst elements (not bytes) written into dst.
*/
static int Unpack16(const uint8_t src[], size_t srcSize, uint16_t dst[]);
/** Unpack the data in src[], and expand it into dst[]. The src[] data was
written by a previous call to Pack8.
@param src Input data to unpack, previously created by Pack8.
@param srcSize Number of bytes of src to unpack
@param dst Buffer (allocated by caller) to expand the src[] into.
@return the number of bytes written into dst.
*/
static int Unpack8(const uint8_t src[], size_t srcSize, uint8_t dst[]);
/** Unpack the data from src[], skip the first dstSkip bytes, then write
dstWrite bytes into dst[]. The src[] data was written by a previous
call to Pack8. Return the number of bytes actually writtten into dst[]
@param src Input data to unpack, previously created by Pack8.
@param dst Buffer (allocated by caller) to expand the src[] into.
@param dstSkip Number of bytes of unpacked src to skip before writing
into dst
@param dstWrite Number of bytes of unpacked src to write into dst (after
skipping dstSkip bytes)
*/
static void Unpack8(uint8_t dst[], size_t dstSkip, size_t dstWrite,
const uint8_t src[]);
};
#endif