diff options
| -rw-r--r-- | bin/.gitignore | 1 | ||||
| -rw-r--r-- | bin/Makefile | 2 | ||||
| -rw-r--r-- | bin/scheme.c | 136 |
3 files changed, 138 insertions, 1 deletions
diff --git a/bin/.gitignore b/bin/.gitignore index 1904feb4..b1c26730 100644 --- a/bin/.gitignore +++ b/bin/.gitignore @@ -9,6 +9,7 @@ pbcopy pbd pbpaste pngo +scheme wake xx klon diff --git a/bin/Makefile b/bin/Makefile index 3cec67ee..c04789d4 100644 --- a/bin/Makefile +++ b/bin/Makefile @@ -1,4 +1,4 @@ -ANY_BINS = atch dtch gfxx glitch hnel pbcopy pbd pbpaste pngo wake xx +ANY_BINS = atch dtch gfxx glitch hnel pbcopy pbd pbpaste pngo scheme wake xx BSD_BINS = klon watch LIN_BINS = bri fbatt fbclock ALL_BINS = $(ANY_BINS) $(BSD_BINS) $(LIN_BINS) diff --git a/bin/scheme.c b/bin/scheme.c new file mode 100644 index 00000000..f1b12eae --- /dev/null +++ b/bin/scheme.c @@ -0,0 +1,136 @@ +/* + * Copyright (C) 2018 Curtis 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 <arpa/inet.h> +#include <err.h> +#include <math.h> +#include <stdint.h> +#include <stdio.h> +#include <stdlib.h> +#include <string.h> +#include <sysexits.h> +#include <zlib.h> + +struct Hsv { + double h, s, v; +}; + +struct Rgb { + uint8_t r, g, b; +}; + +static struct Rgb toRgb(struct Hsv hsv) { + double c = hsv.v * hsv.s; + double h = hsv.h / 60.0; + double x = c * (1.0 - fabs(fmod(h, 2.0) - 1.0)); + double m = hsv.v - c; + double r = m, g = m, b = m; + if (h <= 1.0) { r += c; g += x; } + else if (h <= 2.0) { r += x; g += c; } + else if (h <= 3.0) { g += c; b += x; } + else if (h <= 4.0) { g += x; b += c; } + else if (h <= 5.0) { r += x; b += c; } + else if (h <= 6.0) { r += c; b += x; } + return (struct Rgb) { r * 255.0, g * 255.0, b * 255.0 }; +} + +static uint32_t crc; +static void pngWrite(const void *ptr, size_t size) { + fwrite(ptr, size, 1, stdout); + if (ferror(stdout)) err(EX_IOERR, "(stdout)"); + crc = crc32(crc, ptr, size); +} +static void pngInt(uint32_t host) { + uint32_t net = htonl(host); + pngWrite(&net, 4); +} +static void pngChunk(const char *type, uint32_t size) { + pngInt(size); + crc = crc32(0, Z_NULL, 0); + pngWrite(type, 4); +} +enum { NONE, SUB, UP, AVERAGE, PAETH }; + +static void png(const struct Hsv *hsv, uint8_t len) { + uint32_t swatchWidth = 64; + uint32_t swatchHeight = 64; + uint32_t columns = 8; + uint32_t rows = (len + columns - 1) / columns; + uint32_t width = swatchWidth * columns; + uint32_t height = swatchHeight * rows; + + pngWrite("\x89PNG\r\n\x1A\n", 8); + + pngChunk("IHDR", 13); + pngInt(width); + pngInt(height); + pngWrite("\x08\x03\0\0\0", 5); + pngInt(crc); + + pngChunk("PLTE", 3 * len); + for (uint8_t i = 0; i < len; ++i) { + struct Rgb rgb = toRgb(hsv[i]); + pngWrite(&rgb, 3); + } + pngInt(crc); + + uint8_t data[height][1 + width]; + memset(data, 0, sizeof(data)); + for (uint32_t y = 0; y < height; ++y) { + data[y][0] = (y % swatchHeight) ? UP : SUB; + } + for (uint8_t i = 0; i < len; ++i) { + uint32_t y = swatchHeight * (i / columns); + uint32_t x = swatchWidth * (i % columns); + data[y][1 + x] = x ? 1 : i; + } + + uLong size = compressBound(sizeof(data)); + uint8_t deflate[size]; + int error = compress(deflate, &size, (Byte *)data, sizeof(data)); + if (error != Z_OK) errx(EX_SOFTWARE, "compress: %d", error); + + pngChunk("IDAT", size); + pngWrite(deflate, size); + pngInt(crc); + + pngChunk("IEND", 0); + pngInt(crc); +} + +int main() { + struct Hsv scheme[16] = { + { 0.0, 1.0, 1.0 }, + { 45.0, 1.0, 1.0 }, + { 90.0, 1.0, 1.0 }, + { 135.0, 1.0, 1.0 }, + { 180.0, 1.0, 1.0 }, + { 225.0, 1.0, 1.0 }, + { 270.0, 1.0, 1.0 }, + { 315.0, 1.0, 1.0 }, + { 0.0, 0.5, 1.0 }, + { 45.0, 0.5, 1.0 }, + { 90.0, 0.5, 1.0 }, + { 135.0, 0.5, 1.0 }, + { 180.0, 0.5, 1.0 }, + { 225.0, 0.5, 1.0 }, + { 270.0, 0.5, 1.0 }, + { 315.0, 0.5, 1.0 }, + }; + png(scheme, 16); + return EX_OK; +} |