Initial revision

svn path=/import/jshaw/libsprite/; revision=9980

2 files changed, 220 insertions, 0 deletions

diff --git a/trunk/build.sh b/trunk/build.sh
new file mode 100755
index 0000000..c40783b
--- /dev/null
+++ b/trunk/build.sh
@@ -0,0 +1,2 @@
+#!/bin/bash
+gcc -W -Wall -pedantic -Werror -std=c99 -o libsprite libsprite.c
diff --git a/trunk/libsprite.c b/trunk/libsprite.c
new file mode 100644
index 0000000..f73d45b
--- /dev/null
+++ b/trunk/libsprite.c
@@ -0,0 +1,218 @@
+#include "assert.h"
+#include "stdio.h"
+#include "stdlib.h"
+#include "stdint.h"
+#include "stdbool.h"
+#include "string.h"
+
+#define LOGDBG(...) printf(__VA_ARGS__);
+
+#define BTUINT(b) (b[0] | (b[1] << 8) | (b[2] << 16) | (b[3] << 24))
+
+struct sprite_area_control_block {
+	uint32_t spriteCount;
+	uint32_t extensionBytes; /* size of extensionWords byte array */
+	unsigned char* extensionWords;
+};
+
+struct sprite_mode {
+	uint32_t colorbpp;
+	uint32_t xdpi;
+	uint32_t ydpi;
+};
+
+struct sprite_header {
+	char name[13];
+	struct sprite_mode* mode;
+	bool hasMask;
+	uint32_t maskbpp;
+	bool hasPalette;
+	uint32_t paletteSize;
+	uint32_t* palette;
+};
+
+uint32_t sprite_read_word(FILE* stream)
+{
+	unsigned char b[4];
+	size_t bytesRead = fread(b, 1, 4, stream);
+	
+	if (bytesRead != 4) {
+		printf("Unexpected EOF\n"); /* TODO, have better error handling, don't exit here */
+		exit(EXIT_FAILURE);
+	}
+
+	return BTUINT(b);
+}
+
+void sprite_read_bytes(FILE* stream, unsigned char* buf, size_t count)
+{
+	size_t bytesRead = fread(buf, 1, count, stream);
+	
+	if (bytesRead != count) {
+		printf("Unexpected EOF\n");
+		exit(EXIT_FAILURE);
+	}
+}
+
+struct sprite_mode* sprite_get_mode(uint32_t spriteMode)
+{
+	static struct sprite_mode oldmodes[256];
+	for (uint32_t i = 0; i < 256; i++) {
+		oldmodes[i].colorbpp = 0;
+		oldmodes[i].xdpi     = 0;
+		oldmodes[i].ydpi     = 0;
+	}
+
+	struct sprite_mode* mode = malloc(sizeof(struct sprite_mode));
+
+	uint32_t spriteType = spriteMode >> 27; /* preserve bits 27-31 only */
+	LOGDBG("spriteType %u\n", spriteType);
+
+	if (spriteType != 0) {
+		mode->xdpi = (spriteMode & 0x07ffc000) >> 14; /* preserve bits 14-26 only */
+		mode->ydpi = (spriteMode & 0x00003ffe) >> 1; /* preserve bits 1-13 only */
+		switch (spriteType) {
+		case 1:
+			mode->colorbpp = 1; break;
+		case 2:
+			mode->colorbpp = 2; break;
+		case 3:
+			mode->colorbpp = 4; break;
+		case 4:
+			mode->colorbpp = 8; break;
+		case 5:
+			mode->colorbpp = 16; break;
+		case 6:
+			mode->colorbpp = 32; break;
+		case 7:
+			mode->colorbpp = 23; break; /* CMYK */
+		case 8:
+			mode->colorbpp = 24; break;
+		}
+	} else {
+		memcpy(mode, &(oldmodes[spriteMode]), sizeof(struct sprite_mode));
+	}
+
+	/*LOGDBG("verticalDPI %u\n", verticalDPI);
+	LOGDBG("horizontalDPI %u\n", horizontalDPI);*/
+
+	return mode;
+}
+
+int main(int argc, char *argv[])
+{
+	if (argc < 2) {
+		printf("Usage: libsprite spritefile\n");
+		exit(EXIT_FAILURE);
+	}
+
+	char* filename = argv[1];
+
+	FILE* spritefile = fopen(filename, "rb");
+	if (spritefile == NULL) {
+		printf("Can't load spritefile %s\n", filename);
+		exit(EXIT_FAILURE);
+	}
+
+	LOGDBG("Loading %s\n", filename);
+
+	uint32_t spriteCount = sprite_read_word(spritefile);
+	uint32_t firstSpriteOffset = sprite_read_word(spritefile);
+	uint32_t firstFreeWordOffset = sprite_read_word(spritefile);
+	uint32_t extensionByteCount = 16 - firstSpriteOffset;
+
+	LOGDBG("spriteCount %u\n", spriteCount);
+	LOGDBG("firstSpriteOffset %u\n", firstSpriteOffset);
+	LOGDBG("firstFreeWordOffset %u\n", firstFreeWordOffset);
+	LOGDBG("extensionByteCount %u\n", extensionByteCount);
+
+	unsigned char* extensionWords = NULL;
+	if (extensionByteCount > 0) {
+		extensionWords = malloc(extensionByteCount); /* where to free() this? */
+		sprite_read_bytes(spritefile, extensionWords, extensionByteCount);
+	}
+
+	for (uint32_t i = 0; i < spriteCount; i++) {
+		uint32_t nextSpriteOffset = sprite_read_word(spritefile);
+
+		unsigned char* name = malloc(13); /* last byte for 0 terminator */
+		sprite_read_bytes(spritefile, name, 12);
+		name[12] = '\0';
+
+		uint32_t width         = sprite_read_word(spritefile);
+		uint32_t height        = sprite_read_word(spritefile);
+		uint32_t firstUsedBit  = sprite_read_word(spritefile); /* old format only (spriteType = 0) */
+		uint32_t lastUsedBit   = sprite_read_word(spritefile);
+		uint32_t imageOffset   = sprite_read_word(spritefile);
+		assert(imageOffset >= 44); /* should never be smaller than the size of the header) */
+
+		uint32_t maskOffset    = sprite_read_word(spritefile);
+		uint32_t spriteModeWord= sprite_read_word(spritefile);
+
+		struct sprite_mode* spriteMode = sprite_get_mode(spriteModeWord);
+
+		uint32_t paletteSize  = imageOffset - 44;
+		bool hasPalette = (paletteSize > 0);
+
+		bool hasMask;
+		uint32_t imageSize;
+		uint32_t maskSize;
+
+		if (imageOffset == maskOffset) {
+			hasMask   = false;
+			imageSize = nextSpriteOffset - 44 - paletteSize;
+			maskSize  = 0;
+		} else {
+			hasMask   = true;
+			imageSize = maskOffset - imageOffset;
+			maskSize  = nextSpriteOffset - 44 - paletteSize - imageSize;
+		}
+		
+		LOGDBG("\nLoading sprite %u\n", i);
+		LOGDBG("nextSpriteOffset %u\n", nextSpriteOffset);
+		LOGDBG("name %s\n", name);
+		LOGDBG("width %u\n", width);
+		LOGDBG("height %u\n", height);
+		LOGDBG("firstUsedBit %u\n", firstUsedBit);
+		LOGDBG("lastUsedBit %u\n", lastUsedBit);
+		LOGDBG("imageOffset %u\n", imageOffset);
+		LOGDBG("maskOffset %u\n", maskOffset);
+		LOGDBG("spriteModeWord %u\n", spriteModeWord);
+		LOGDBG("\tcolorbpp %u\n", spriteMode->colorbpp);
+		LOGDBG("\txdpi %u\n", spriteMode->xdpi);
+		LOGDBG("\tydpi %u\n", spriteMode->ydpi);
+
+		LOGDBG("hasPalette %s\n", hasPalette ? "YES" : "NO");
+		LOGDBG("paletteSize %u\n", paletteSize);
+		LOGDBG("imageSize %u\n", imageSize);
+		LOGDBG("hasMask %s\n", hasMask ? "YES" : "NO");
+		LOGDBG("maskSize %u\n", maskSize);
+		
+		uint32_t* palette = NULL;
+		if (paletteSize > 0) {
+			assert(paletteSize % 8 == 0);
+			palette = malloc(sizeof(uint32_t) * paletteSize);
+			uint32_t paletteEntries = paletteSize / 8;
+
+			/* Each palette entry is two words big
+			 * The section entry is a duplicate of the first
+             * I think this is in case you ever wanted flashing colours
+             */
+			for (uint32_t j = 0; j < paletteEntries; j++) {
+				uint32_t word1 = sprite_read_word(spritefile);
+				uint32_t word2 = sprite_read_word(spritefile);
+				assert(word1 == word2); /* TODO: if they aren't, START FLASHING */
+				
+				palette[j] = word1;
+			}
+		}
+
+		unsigned char* image = malloc(imageSize);
+		sprite_read_bytes(spritefile, image, imageSize);
+
+		unsigned char* mask = malloc(maskSize);
+		sprite_read_bytes(spritefile, mask, maskSize);
+	}
+
+	return EXIT_SUCCESS;
+}