michael@0: 
michael@0: /*
michael@0:  * Copyright 2008 The Android Open Source Project
michael@0:  *
michael@0:  * Use of this source code is governed by a BSD-style license that can be
michael@0:  * found in the LICENSE file.
michael@0:  */
michael@0: 
michael@0: 
michael@0: #ifndef SkPackBits_DEFINED
michael@0: #define SkPackBits_DEFINED
michael@0: 
michael@0: #include "SkTypes.h"
michael@0: 
michael@0: class SkPackBits {
michael@0: public:
michael@0:     /** Given the number of 16bit values that will be passed to Pack16,
michael@0:         returns the worst-case size needed for the dst[] buffer.
michael@0:     */
michael@0:     static size_t ComputeMaxSize16(int count);
michael@0: 
michael@0:     /** Given the number of 8bit values that will be passed to Pack8,
michael@0:         returns the worst-case size needed for the dst[] buffer.
michael@0:     */
michael@0:     static size_t ComputeMaxSize8(int count);
michael@0: 
michael@0:     /** Write the src array into a packed format. The packing process may end
michael@0:         up writing more bytes than it read, so dst[] must be large enough.
michael@0:         @param src      Input array of 16bit values
michael@0:         @param count    Number of entries in src[]
michael@0:         @param dst      Buffer (allocated by caller) to write the packed data
michael@0:                         into
michael@0:         @return the number of bytes written to dst[]
michael@0:     */
michael@0:     static size_t Pack16(const uint16_t src[], int count, uint8_t dst[]);
michael@0: 
michael@0:     /** Write the src array into a packed format. The packing process may end
michael@0:         up writing more bytes than it read, so dst[] must be large enough.
michael@0:         @param src      Input array of 8bit values
michael@0:         @param count    Number of entries in src[]
michael@0:         @param dst      Buffer (allocated by caller) to write the packed data
michael@0:                         into
michael@0:         @return the number of bytes written to dst[]
michael@0:     */
michael@0:     static size_t Pack8(const uint8_t src[], int count, uint8_t dst[]);
michael@0: 
michael@0:     /** Unpack the data in src[], and expand it into dst[]. The src[] data was
michael@0:         written by a previous call to Pack16.
michael@0:         @param src  Input data to unpack, previously created by Pack16.
michael@0:         @param srcSize  Number of bytes of src to unpack
michael@0:         @param dst  Buffer (allocated by caller) to expand the src[] into.
michael@0:         @return the number of dst elements (not bytes) written into dst.
michael@0:     */
michael@0:     static int Unpack16(const uint8_t src[], size_t srcSize, uint16_t dst[]);
michael@0: 
michael@0:     /** Unpack the data in src[], and expand it into dst[]. The src[] data was
michael@0:         written by a previous call to Pack8.
michael@0:         @param src      Input data to unpack, previously created by Pack8.
michael@0:         @param srcSize  Number of bytes of src to unpack
michael@0:         @param dst      Buffer (allocated by caller) to expand the src[] into.
michael@0:         @return the number of bytes written into dst.
michael@0:     */
michael@0:     static int Unpack8(const uint8_t src[], size_t srcSize, uint8_t dst[]);
michael@0: 
michael@0:     /** Unpack the data from src[], skip the first dstSkip bytes, then write
michael@0:         dstWrite bytes into dst[]. The src[] data was written by a previous
michael@0:         call to Pack8. Return the number of bytes actually writtten into dst[]
michael@0:         @param src      Input data to unpack, previously created by Pack8.
michael@0:         @param dst      Buffer (allocated by caller) to expand the src[] into.
michael@0:         @param dstSkip  Number of bytes of unpacked src to skip before writing
michael@0:                         into dst
michael@0:         @param dstWrite Number of bytes of unpacked src to write into dst (after
michael@0:                         skipping dstSkip bytes)
michael@0:     */
michael@0:     static void Unpack8(uint8_t dst[], size_t dstSkip, size_t dstWrite,
michael@0:                         const uint8_t src[]);
michael@0: };
michael@0: 
michael@0: #endif