From 16912026dbdd7dc9e238492d9d83e37270ae4f06 Mon Sep 17 00:00:00 2001
From: Magnus Auvinen <magnus.auvinen@gmail.com>
Date: Sun, 17 Aug 2008 07:05:16 +0000
Subject: added cl_layershot. fixed some bugs in the network

---
 src/engine/e_huffman.h | 106 +++++++++++++++++++++++++++++++++++--------------
 1 file changed, 77 insertions(+), 29 deletions(-)

(limited to 'src/engine/e_huffman.h')

diff --git a/src/engine/e_huffman.h b/src/engine/e_huffman.h
index 84c71e60..c4e20223 100644
--- a/src/engine/e_huffman.h
+++ b/src/engine/e_huffman.h
@@ -1,43 +1,91 @@
+#ifndef __HUFFMAN_HEADER__
+#define __HUFFMAN_HEADER__
+
+#ifdef __cplusplus
+extern "C" {
+#endif
 
 enum
 {
-	MAX_SYMBOL_SIZE=8,
-	MAX_NODES=1024*8
-};
+	HUFFMAN_EOF_SYMBOL = 256,
 
-typedef struct
-{
-	int i;
-} HUFFSYMBOL;
+	HUFFMAN_MAX_SYMBOLS=HUFFMAN_EOF_SYMBOL+1,
+	HUFFMAN_MAX_NODES=HUFFMAN_MAX_SYMBOLS*2-1,
+	
+	HUFFMAN_LUTBITS = 10,
+	HUFFMAN_LUTSIZE = (1<<HUFFMAN_LUTBITS),
+	HUFFMAN_LUTMASK = (HUFFMAN_LUTSIZE-1)
+};
 
-typedef struct HUFFNODE_t
+typedef struct HUFFMAN_NODE
 {
-	int frequency;
-	
-	int symbol_size;
-	unsigned char symbol[MAX_SYMBOL_SIZE];
-	
-	int num_bits;
+	/* symbol */
 	unsigned bits;
+	unsigned num_bits;
+
+	/* don't use pointers for this. shorts are smaller so we can fit more data into the cache */
+	unsigned short leafs[2];
 
-	struct HUFFNODE_t *parent;
-	struct HUFFNODE_t *zero;
-	struct HUFFNODE_t *one;
-} HUFFNODE;
+	/* what the symbol represents */
+	unsigned char symbol;
+} HUFFMAN_NODE;
 
-typedef struct
+typedef struct HUFFMAN_STATE
 {
-	HUFFNODE nodes[MAX_NODES];
-	HUFFNODE *start_node;
-	int num_symbols;
+	HUFFMAN_NODE nodes[HUFFMAN_MAX_NODES];
+	HUFFMAN_NODE *decode_lut[HUFFMAN_LUTSIZE];
+	HUFFMAN_NODE *start_node;
 	int num_nodes;
-} HUFFSTATE;
+} HUFFMAN_STATE;
+
+/*
+	Function: huffman_init
+		Inits the compressor/decompressor.
+
+	Parameters:
+		huff - Pointer to the state to init
+		frequencies - A pointer to an array of 256 entries of the frequencies of the bytes
+
+	Remarks:
+		- Does no allocation what so ever.
+		- You don't have to call any cleanup functions when you are done with it
+*/
+void huffman_init(HUFFMAN_STATE *huff, const unsigned *frequencies);
+
+/*
+	Function: huffman_compress
+		Compresses a buffer and outputs a compressed buffer.
+
+	Parameters:
+		huff - Pointer to the huffman state
+		input - Buffer to compress
+		input_size - Size of the buffer to compress
+		output - Buffer to put the compressed data into
+		output_size - Size of the output buffer
+
+	Returns:
+		Returns the size of the compressed data. Negative value on failure.
+*/
+int huffman_compress(HUFFMAN_STATE *huff, const void *input, int input_size, void *output, int output_size);
+
+/*
+	Function: huffman_decompress
+		Decompresses a buffer
+
+	Parameters:
+		huff - Pointer to the huffman state
+		input - Buffer to decompress
+		input_size - Size of the buffer to decompress
+		output - Buffer to put the uncompressed data into
+		output_size - Size of the output buffer
 
+	Returns:
+		Returns the size of the uncompressed data. Negative value on failure.
+*/
+int huffman_decompress(HUFFMAN_STATE *huff, const void *input, int input_size, void *output, int output_size);
 
-void huffman_add_symbol(HUFFSTATE *huff, int frequency, int size, unsigned char *symbol);
-void huffman_init(HUFFSTATE *huff);
-void huffman_construct_tree(HUFFSTATE *huff);
-int huffman_compress(HUFFSTATE *huff, const void *input, int input_size, void *output, int output_size);
-int huffman_decompress(HUFFSTATE *huff, const void *input, int input_size, void *output, int output_size);
+#ifdef __cplusplus
+}
+#endif
 
-int huffman_test();
+#endif /* __HUFFMAN_HEADER__ */
-- 
cgit 1.4.1