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-rw-r--r--gfx/png.h108
1 files changed, 0 insertions, 108 deletions
diff --git a/gfx/png.h b/gfx/png.h
deleted file mode 100644
index 0df4699b..00000000
--- a/gfx/png.h
+++ /dev/null
@@ -1,108 +0,0 @@
-/* Copyright (C) 2018  June McEnroe <june@causal.agency>
- *
- * This program is free software: you can redistribute it and/or modify
- * it under the terms of the GNU Affero General Public License as published by
- * the Free Software Foundation, either version 3 of the License, or
- * (at your option) any later version.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- * GNU Affero General Public License for more details.
- *
- * You should have received a copy of the GNU Affero General Public License
- * along with this program.  If not, see <http://www.gnu.org/licenses/>.
- */
-
-#include <err.h>
-#include <stdint.h>
-#include <stdio.h>
-#include <stdlib.h>
-#include <sysexits.h>
-
-static inline uint32_t pngCRCTable(uint8_t n) {
-	static uint32_t table[256];
-	if (table[1]) return table[n];
-	for (int i = 0; i < 256; ++i) {
-		table[i] = i;
-		for (int j = 0; j < 8; ++j) {
-			table[i] = (table[i] >> 1) ^ (table[i] & 1 ? 0xEDB88320 : 0);
-		}
-	}
-	return table[n];
-}
-
-static uint32_t pngCRC;
-
-static inline void pngWrite(FILE *file, const uint8_t *ptr, uint32_t len) {
-	if (!fwrite(ptr, len, 1, file)) err(EX_IOERR, "pngWrite");
-	for (uint32_t i = 0; i < len; ++i) {
-		pngCRC = pngCRCTable(pngCRC ^ ptr[i]) ^ (pngCRC >> 8);
-	}
-}
-static inline void pngInt32(FILE *file, uint32_t n) {
-	pngWrite(file, (uint8_t []) { n >> 24, n >> 16, n >> 8, n }, 4);
-}
-static inline void pngChunk(FILE *file, char type[static 4], uint32_t len) {
-	pngInt32(file, len);
-	pngCRC = ~0;
-	pngWrite(file, (uint8_t *)type, 4);
-}
-
-enum {
-	PNGGrayscale,
-	PNGTruecolor = 2,
-	PNGIndexed,
-	PNGAlpha,
-};
-
-static inline void pngHead(
-	FILE *file, uint32_t width, uint32_t height, uint8_t depth, uint8_t color
-) {
-	pngWrite(file, (uint8_t *)"\x89PNG\r\n\x1A\n", 8);
-	pngChunk(file, "IHDR", 13);
-	pngInt32(file, width);
-	pngInt32(file, height);
-	pngWrite(file, &depth, 1);
-	pngWrite(file, &color, 1);
-	pngWrite(file, (uint8_t []) { 0, 0, 0 }, 3);
-	pngInt32(file, ~pngCRC);
-}
-
-static inline void pngPalette(FILE *file, const uint8_t *pal, uint32_t len) {
-	pngChunk(file, "PLTE", len);
-	pngWrite(file, pal, len);
-	pngInt32(file, ~pngCRC);
-}
-
-enum {
-	PNGNone,
-	PNGSub,
-	PNGUp,
-	PNGAverage,
-	PNGPaeth,
-};
-
-static inline void pngData(FILE *file, const uint8_t *data, uint32_t len) {
-	uint32_t adler1 = 1, adler2 = 0;
-	for (uint32_t i = 0; i < len; ++i) {
-		adler1 = (adler1 + data[i]) % 65521;
-		adler2 = (adler1 + adler2) % 65521;
-	}
-	uint32_t zlen = 2 + 5 * ((len + 0xFFFE) / 0xFFFF) + len + 4;
-	pngChunk(file, "IDAT", zlen);
-	pngWrite(file, (uint8_t []) { 0x08, 0x1D }, 2);
-	for (; len > 0xFFFF; data += 0xFFFF, len -= 0xFFFF) {
-		pngWrite(file, (uint8_t []) { 0x00, 0xFF, 0xFF, 0x00, 0x00 }, 5);
-		pngWrite(file, data, 0xFFFF);
-	}
-	pngWrite(file, (uint8_t []) { 0x01, len, len >> 8, ~len, ~len >> 8 }, 5);
-	pngWrite(file, data, len);
-	pngInt32(file, adler2 << 16 | adler1);
-	pngInt32(file, ~pngCRC);
-}
-
-static inline void pngTail(FILE *file) {
-	pngChunk(file, "IEND", 0);
-	pngInt32(file, ~pngCRC);
-}