1 files changed, 73 insertions, 0 deletions
diff --git a/indra/llmessage/patch_dct.h b/indra/llmessage/patch_dct.h
new file mode 100644
index 0000000000..d5c0d067fc
--- /dev/null
+++ b/indra/llmessage/patch_dct.h
@@ -0,0 +1,73 @@
+/** 
+ * @file patch_dct.h
+ * @brief Function declarations for DCT and IDCT routines
+ *
+ * Copyright (c) 2000-$CurrentYear$, Linden Research, Inc.
+ * $License$
+ */
+
+#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