From 26a0a2abd516ae0d7a8b5e6bc6a1dc85ca983fbb Mon Sep 17 00:00:00 2001 From: Jorj Bauer Date: Thu, 10 Feb 2022 16:10:56 -0500 Subject: [PATCH] utility to generate blended pixel values --- util/gen-palette.cpp | 211 +++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 211 insertions(+) create mode 100644 util/gen-palette.cpp diff --git a/util/gen-palette.cpp b/util/gen-palette.cpp new file mode 100644 index 0000000..0190d36 --- /dev/null +++ b/util/gen-palette.cpp @@ -0,0 +1,211 @@ +#include +#include +#include + +#ifndef min +#define min(a,b) (((a) < (b)) ? (a) : (b)) +#endif +#ifndef max +#define max(a,b) (((a) > (b)) ? (a) : (b)) +#endif + +#define _565To332(c) ((((c) & 0xe000) >> 8) | (((c) & 0x700) >> 6) | (((c) & 0x18) >> 3)) + + +static void rgb_to_hsv(double r, double g, double b, double *h, double *s, double *v) +{ + // Range for these equations is [0..1] not [0..255] + r = r / 255.0; + g = g / 255.0; + b = b / 255.0; + + // h, s, v = hue, saturation, value + double cmax = max(r, max(g, b)); // maximum of r, g, b + double cmin = min(r, min(g, b)); // minimum of r, g, b + double diff = cmax - cmin; // diff of cmax and cmin. + + // if cmax and cmax are equal then h = 0 + if (cmax == cmin) + *h = 0; + + // if cmax equal r then compute h + else if (cmax == r) + *h = (int)(60 * ((g - b) / diff) + 360) % 360; + + // if cmax equal g then compute h + else if (cmax == g) + *h = (int)(60 * ((b - r) / diff) + 120) % 360; + + // if cmax equal b then compute h + else if (cmax == b) + *h = (int)(60 * ((r - g) / diff) + 240) % 360; + + // if cmax equal zero + if (cmax == 0) + *s = 0; + else + *s = (diff / cmax) * 100; + + // compute v + *v = cmax * 100; +} + +static void hsv_to_rgb(double H, double S, double V, uint8_t *R, uint8_t *G, uint8_t *B) +{ + float s = S/100; + float v = V/100; + float C = s*v; + float X = C*(1-fabs(fmod(H/60.0, 2)-1)); + float m = v-C; + float r,g,b; + if(H >= 0 && H < 60){ + r = C,g = X,b = 0; + } + else if(H >= 60 && H < 120){ + r = X,g = C,b = 0; + } + else if(H >= 120 && H < 180){ + r = 0,g = C,b = X; + } + else if(H >= 180 && H < 240){ + r = 0,g = X,b = C; + } + else if(H >= 240 && H < 300){ + r = X,g = 0,b = C; + } + else{ + r = C,g = 0,b = X; + } + *R = (r+m)*255; + *G = (g+m)*255; + *B = (b+m)*255; +} + +// blend two 24-bit packed colors +uint32_t blendColors(uint32_t a, uint32_t b) +{ + uint8_t r1, r2, g1, g2, b1, b2; + r1 = (a & 0xFF0000) >> 16; + g1 = (a & 0x00FF00) >> 8; + b1 = (a & 0x0000FF); + r2 = (b & 0xFF0000) >> 16; + g2 = (b & 0x00FF00) >> 8; + b2 = (b & 0x0000FF); + + double h1, s1, v1, h2, s2, v2; + rgb_to_hsv(r1, g1, b1, &h1, &s1, &v1); + rgb_to_hsv(r2, g2, b2, &h2, &s2, &v2); + + hsv_to_rgb((h1+h2)/2, (s1+s2)/2, (v1+v2)/2, &r1, &g1, &b1); + uint32_t ret = (r1 << 16) | (g1 << 8) | (b1); + + return ret; +} + +// RGB map of each of the lowres colors +const uint8_t loresPixelColors[16][3] = { { 0, 0, 0 }, // black + { 0xAC, 0x12, 0x4C }, // magenta + { 0x00, 0x07, 0x83 }, // dark blue + { 0xAA, 0x1A, 0xD1 }, // purple + { 0x00, 0x83, 0x2F }, // dark green + { 0x9F, 0x97, 0x7E }, // drak grey + { 0x00, 0x8A, 0xB5 }, // medium blue + { 0x9F, 0x9E, 0xFF }, // light blue + { 0x7A, 0x5F, 0x00 }, // brown + { 0xFF, 0x72, 0x47 }, // orange + { 0x78, 0x68, 0x7F }, // light gray + { 0xFF, 0x7A, 0xCF }, // pink + { 0x6F, 0xE6, 0x2C }, // green + { 0xFF, 0xF6, 0x7B }, // yellow + { 0x6C, 0xEE, 0xB2 }, // aqua + { 0xFF, 0xFF, 0xFF } // white +}; + +static const uint16_t palette16[16] = { + 0x0000, // 0 black + 0xC006, // 1 magenta + 0x0010, // 2 dark blue + 0xA1B5, // 3 purple + 0x0480, // 4 dark green + 0x6B4D, // 5 dark grey + 0x1B9F, // 6 med blue + 0x0DFD, // 7 light blue + 0x92A5, // 8 brown + 0xF8C5, // 9 orange + 0x9555, // 10 light gray + 0xFCF2, // 11 pink + 0x07E0, // 12 green + 0xFFE0, // 13 yellow + 0x87F0, // 14 aqua + 0xFFFF // 15 white +}; + +#define color16To32(x) ( (((x) & 0xF800) << 8) | (((x) & 0x07E0) << 5) | (((x) & 0x001F)<<3) ) +#define packColor32(x) ( (x[0] << 16) | (x[1] << 8) | (x[2]) ) +#define unpackRed(x) ( ((x) & 0xFF0000) >> 16 ) +#define unpackGreen(x) ( ((x) & 0xFF00) >> 8 ) +#define unpackBlue(x) ( ((x) & 0xFF) ) +// FIXME this blend could be optimized - and it's a dumb blend that +// just averages RGB values individually, rather than trying to find a +// sane blend of 2 pixels. Needs thought. +#define luminanceFromRGB(r,g,b) ( ((r)*0.2126) + ((g)*0.7152) + ((b)*0.0722) ) + +int main(int argc, char *argv[]) +{ + for (int i=0; i<16; i++) { + printf("color %d: 32-bit 0x%.8X 16-bit 0x%.4X 8-bit 0x%.2X\n", + i, + packColor32(loresPixelColors[i]), + palette16[i], + _565To332(palette16[i])); + + } + + uint32_t mix32[16][16]; + uint16_t mix16[16][16]; + uint8_t mix8[16][16]; + + for (int a=0; a<16; a++) { + for (int b=0; b<16; b++) { + uint32_t v = blendColors(packColor32(loresPixelColors[a]), + packColor32(loresPixelColors[b])); + uint16_t v16 = ((unpackRed(v) & 0xF8) << 8) | + ((unpackGreen(v) & 0xFC) << 3) | + ((unpackBlue(v) & 0xF8) >> 3); + uint8_t v8 = _565To332(v16); + mix32[a][b] = v; + mix16[a][b] = v16; + mix8[a][b] = v8; + } + } + + printf("uint8_t mix8[16][16] = {\n"); + for (int a=0; a<16; a++) { + for (int b=0; b<16; b++) { + printf("0x%.2X, ", mix8[a][b]); + } + printf("\n"); + } + printf("};\n\n"); + + printf("uint16_t mix16[16][16] = {\n"); + for (int a=0; a<16; a++) { + for (int b=0; b<16; b++) { + printf("0x%.4X, ", mix16[a][b]); + } + printf("\n"); + } + printf("};\n\n"); + + printf("uint32_t mix32[16][16] = {\n"); + for (int a=0; a<16; a++) { + for (int b=0; b<16; b++) { + printf("0x%.8X, ", mix32[a][b]); + } + printf("\n"); + } + printf("};\n\n"); + + return 0; +} +