diff options
| -rw-r--r-- | bin/glitch.c | 31 |
1 files changed, 18 insertions, 13 deletions
diff --git a/bin/glitch.c b/bin/glitch.c index 57e67059..c1b57611 100644 --- a/bin/glitch.c +++ b/bin/glitch.c @@ -127,17 +127,25 @@ static struct PACKED { } header; static_assert(13 == sizeof(header), "header size"); -static size_t lineSize(void) { +static size_t pixelBits(void) { switch (header.color) { - case Grayscale: return (header.width * 1 * header.depth + 7) / 8; - case Truecolor: return (header.width * 3 * header.depth + 7) / 8; - case Indexed: return (header.width * 1 * header.depth + 7) / 8; - case GrayscaleAlpha: return (header.width * 2 * header.depth + 7) / 8; - case TruecolorAlpha: return (header.width * 4 * header.depth + 7) / 8; + case Grayscale: return 1 * header.depth; + case Truecolor: return 3 * header.depth; + case Indexed: return 1 * header.depth; + case GrayscaleAlpha: return 2 * header.depth; + case TruecolorAlpha: return 4 * header.depth; default: abort(); } } +static size_t pixelSize(void) { + return (pixelBits() + 7) / 8; +} + +static size_t lineSize(void) { + return (header.width * pixelBits() + 7) / 8; +} + static size_t dataSize(void) { return (1 + lineSize()) * header.height; } @@ -346,14 +354,12 @@ static void scanlines(void) { } static struct Bytes origBytes(uint32_t y, size_t i) { - size_t pixelSize = lineSize() / header.width; - if (!pixelSize) pixelSize = 1; - bool a = (i >= pixelSize), b = (y > 0), c = (a && b); + bool a = (i >= pixelSize()), b = (y > 0), c = (a && b); return (struct Bytes) { .x = lines[y]->data[i], - .a = a ? lines[y]->data[i - pixelSize] : 0, + .a = a ? lines[y]->data[i - pixelSize()] : 0, .b = b ? lines[y - 1]->data[i] : 0, - .c = c ? lines[y - 1]->data[i - pixelSize] : 0, + .c = c ? lines[y - 1]->data[i - pixelSize()] : 0, }; } @@ -421,9 +427,8 @@ static void mirror(void) { } static void zeroX(void) { - size_t pixelSize = lineSize() / header.width; for (uint32_t y = 0; y < header.height; ++y) { - memset(lines[y]->data, 0, pixelSize); + memset(lines[y]->data, 0, pixelSize()); } } |