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[WIP] attempt at factoring out font_atlas linear search

For an unknown reason the result is different
This commit is contained in:
Vftdan 2024-10-03 19:36:56 +02:00
parent 46f8ecd68e
commit 6ebe98e94c
1 changed files with 59 additions and 5 deletions

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@ -125,6 +125,8 @@ bool k_means_iteration(struct k_means_state *state);
void k_means_end(struct k_means_state *state); void k_means_end(struct k_means_state *state);
struct palette *palette_k_means(const struct image *image, const struct palette *prototype); struct palette *palette_k_means(const struct image *image, const struct palette *prototype);
inline static uint8_t closest_chunk_color_symbol(const typeof(float[8][11][0x10]) *chunk_palette_diffs, uint8_t color_pair);
const char *known_file_extensions[] = { const char *known_file_extensions[] = {
".png", ".jpg", ".jpeg", ".jfif", ".jpg", ".gif", ".png", ".jpg", ".jpeg", ".jfif", ".jpg", ".gif",
".tga", ".bmp", ".hdr", ".pnm", 0 ".tga", ".bmp", ".hdr", ".pnm", 0
@ -631,11 +633,9 @@ void convert_8x11(const struct image_pal *img, struct cc_char *characters) {
float min_diff = 0xffffff; float min_diff = 0xffffff;
char closest_sym = 0x00, closest_color = 0xae; char closest_sym = 0x00, closest_color = 0xae;
for (int sym = 0x01; sym <= 0xFF; sym++) { for (int color = 0x00; color <= 0xff; color++) {
if (sym == '\t' || sym == '\n' || sym == '\r' || sym == '\x0e') { {
continue; const int sym = closest_chunk_color_symbol(&chunk_palette_diffs, color);
}
for (int color = 0x00; color <= 0xff; color++) {
float difference = 0; float difference = 0;
for (int oy = 0; oy < 11; oy++) { for (int oy = 0; oy < 11; oy++) {
unsigned char sym_line = font_atlas[sym][oy]; unsigned char sym_line = font_atlas[sym][oy];
@ -793,6 +793,60 @@ struct palette *palette_k_means(const struct image *image, const struct palette
return palette; return palette;
} }
inline static float weighted_glyph_hamming_distance(const GlyphBitmap *lhs, const GlyphBitmap *rhs, typeof(float[11][8]) *weights) {
float dist = 0;
for (int oy = 0; oy < 11; oy++) {
uint8_t sym_line = (*lhs)[oy] ^ (*rhs)[oy];
for (int ox = 0; ox < 8; ox++) {
bool lit = sym_line & (0x80 >> ox);
if (lit) {
dist += (*weights)[oy][ox];
}
}
}
return dist;
}
uint8_t closest_glyph_symbol(const GlyphBitmap *target, typeof(float[11][8]) *weights) {
uint8_t best = 0x01;
float best_dist = weighted_glyph_hamming_distance(target, &font_atlas[best], weights);
for (int sym = 0x02; sym <= 0xFF; sym++) {
if (sym == '\t' || sym == '\n' || sym == '\r' || sym == '\x0e') {
continue;
}
float dist = weighted_glyph_hamming_distance(target, &font_atlas[best], weights);
if (dist <= best_dist) {
best_dist = dist;
best = sym;
}
}
return best;
}
void construct_chunk_color_glyph(GlyphBitmap *result, typeof(float[11][8]) *weights, const typeof(float[8][11][0x10]) *chunk_palette_diffs, uint8_t color_pair) {
uint8_t fg = color_pair >> 4,
bg = color_pair & 0xF;
for (int oy = 0; oy < 11; oy++) {
uint8_t sym_line = 0;
for (int ox = 0; ox < 8; ox++) {
float dist_diff = (*chunk_palette_diffs)[ox][oy][fg] - (*chunk_palette_diffs)[ox][oy][bg];
uint8_t lit = dist_diff > 0;
sym_line |= lit << (7 - ox);
if (weights) {
(*weights)[oy][ox] = lit ? dist_diff : -dist_diff;
}
}
(*result)[oy] = sym_line;
}
}
uint8_t closest_chunk_color_symbol(const typeof(float[8][11][0x10]) *chunk_palette_diffs, uint8_t color_pair) {
GlyphBitmap glyph;
float weights[11][8];
construct_chunk_color_glyph(&glyph, &weights, chunk_palette_diffs, color_pair);
return closest_glyph_symbol(&glyph, &weights);
}
const struct palette DEFAULT_PALETTE = PALETTE( const struct palette DEFAULT_PALETTE = PALETTE(
{ { 0xf0, 0xf0, 0xf0, 0xff } }, { { 0xf0, 0xf0, 0xf0, 0xff } },
{ { 0xf2, 0xb2, 0x33, 0xff } }, { { 0xf2, 0xb2, 0x33, 0xff } },