patch_dct.h
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- /**
- * @file patch_dct.h
- * @brief Function declarations for DCT and IDCT routines
- *
- * $LicenseInfo:firstyear=2000&license=viewergpl$
- *
- * Copyright (c) 2000-2010, Linden Research, Inc.
- *
- * Second Life Viewer Source Code
- * The source code in this file ("Source Code") is provided by Linden Lab
- * to you under the terms of the GNU General Public License, version 2.0
- * ("GPL"), unless you have obtained a separate licensing agreement
- * ("Other License"), formally executed by you and Linden Lab. Terms of
- * the GPL can be found in doc/GPL-license.txt in this distribution, or
- * online at http://secondlifegrid.net/programs/open_source/licensing/gplv2
- *
- * There are special exceptions to the terms and conditions of the GPL as
- * it is applied to this Source Code. View the full text of the exception
- * in the file doc/FLOSS-exception.txt in this software distribution, or
- * online at
- * http://secondlifegrid.net/programs/open_source/licensing/flossexception
- *
- * By copying, modifying or distributing this software, you acknowledge
- * that you have read and understood your obligations described above,
- * and agree to abide by those obligations.
- *
- * ALL LINDEN LAB SOURCE CODE IS PROVIDED "AS IS." LINDEN LAB MAKES NO
- * WARRANTIES, EXPRESS, IMPLIED OR OTHERWISE, REGARDING ITS ACCURACY,
- * COMPLETENESS OR PERFORMANCE.
- * $/LicenseInfo$
- */
- #ifndef LL_PATCH_DCT_H
- #define LL_PATCH_DCT_H
- class LLVector3;
- // Code Values
- const U8 ZERO_CODE = 0x0;
- const U8 ZERO_EOB = 0x2;
- const U8 POSITIVE_VALUE = 0x6;
- const U8 NEGATIVE_VALUE = 0x7;
- const S8 NORMAL_PATCH_SIZE = 16;
- const S8 LARGE_PATCH_SIZE = 32;
- const U8 END_OF_PATCHES = 97;
- #define _PATCH_SIZE_16_AND_32_ONLY
- // Top level header for group of headers
- //typedef struct LL_Group_Header
- //{
- // U16 stride; // 2 = 2
- // U8 patch_size; // 1 = 3
- // U8 layer_type; // 1 = 4
- //} LLGroupHeader;
- class LLGroupHeader
- {
- public:
- U16 stride; // 2 = 2
- U8 patch_size; // 1 = 3
- U8 layer_type; // 1 = 4
- };
- // Individual patch header
- //typedef struct LL_Patch_Header
- //{
- // F32 dc_offset; // 4 bytes
- // U16 range; // 2 = 7 ((S16) FP range (breaks if we need > 32K meters in 1 patch)
- // U8 quant_wbits; // 1 = 8 (upper 4 bits is quant - 2, lower 4 bits is word bits - 2)
- // U16 patchids; // 2 = 10 (actually only uses 10 bits, 5 for each)
- //} LLPatchHeader;
- class LLPatchHeader
- {
- public:
- F32 dc_offset; // 4 bytes
- U16 range; // 2 = 7 ((S16) FP range (breaks if we need > 32K meters in 1 patch)
- U8 quant_wbits; // 1 = 8 (upper 4 bits is quant - 2, lower 4 bits is word bits - 2)
- U16 patchids; // 2 = 10 (actually only uses 10 bits, 5 for each)
- };
- // Compression routines
- void init_patch_compressor(S32 patch_size, S32 patch_stride, S32 layer_type);
- void prescan_patch(F32 *patch, LLPatchHeader *php, F32 &zmax, F32 &zmin);
- void compress_patch(F32 *patch, S32 *cpatch, LLPatchHeader *php, S32 prequant);
- void get_patch_group_header(LLGroupHeader *gopp);
- // Decompression routines
- void set_group_of_patch_header(LLGroupHeader *gopp);
- void init_patch_decompressor(S32 size);
- void decompress_patch(F32 *patch, S32 *cpatch, LLPatchHeader *ph);
- void decompress_patchv(LLVector3 *v, S32 *cpatch, LLPatchHeader *ph);
- #endif