1 /*
2 * Copyright © 2012 Google, Inc.
3 *
4 * This is part of HarfBuzz, a text shaping library.
5 *
6 * Permission is hereby granted, without written agreement and without
7 * license or royalty fees, to use, copy, modify, and distribute this
8 * software and its documentation for any purpose, provided that the
9 * above copyright notice and the following two paragraphs appear in
10 * all copies of this software.
11 *
12 * IN NO EVENT SHALL THE COPYRIGHT HOLDER BE LIABLE TO ANY PARTY FOR
13 * DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES
14 * ARISING OUT OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN
15 * IF THE COPYRIGHT HOLDER HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH
16 * DAMAGE.
17 *
18 * THE COPYRIGHT HOLDER SPECIFICALLY DISCLAIMS ANY WARRANTIES, INCLUDING,
19 * BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
20 * FITNESS FOR A PARTICULAR PURPOSE. THE SOFTWARE PROVIDED HEREUNDER IS
21 * ON AN "AS IS" BASIS, AND THE COPYRIGHT HOLDER HAS NO OBLIGATION TO
22 * PROVIDE MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS.
23 *
24 * Google Author(s): Behdad Esfahbod
25 */
26
27 #ifndef ANSI_PRINT_HH
28 #define ANSI_PRINT_HH
29
30 #include "hb.hh"
31
32 #include <assert.h>
33 #include <stdlib.h>
34 #include <stddef.h>
35 #include <string.h>
36 #include <stdio.h>
37 #include <math.h>
38 #include <fcntl.h>
39 #ifdef HAVE_UNISTD_H
40 #include <unistd.h> /* for isatty() */
41 #endif
42
43 #if defined (_MSC_VER) && (_MSC_VER < 1800)
44 static inline long int
lround(double x)45 lround (double x)
46 {
47 if (x >= 0)
48 return floor (x + 0.5);
49 else
50 return ceil (x - 0.5);
51 }
52 #endif
53
54 #define ESC_E (char)27
55
56 #define CELL_W 8
57 #define CELL_H (2 * CELL_W)
58
59 struct color_diff_t
60 {
dotcolor_diff_t61 int dot (const color_diff_t &o)
62 { return v[0]*o.v[0] + v[1]*o.v[1] + v[2]*o.v[2] + v[3]*o.v[3]; }
63
64 int v[4];
65 };
66
67 struct color_t
68 {
from_ansicolor_t69 static color_t from_ansi (unsigned int x)
70 {
71 color_t c = {(0xFFu<<24) | ((0xFFu*(x&1))<<16) | ((0xFFu*((x >> 1)&1))<<8) | (0xFFu*((x >> 2)&1))};
72 return c;
73 }
to_ansicolor_t74 unsigned int to_ansi ()
75 {
76 return ((v >> 23) & 1) | ((v >> 14)&2) | ((v >> 5)&4);
77 }
78
diffcolor_t79 color_diff_t diff (const color_t &o)
80 {
81 color_diff_t d;
82 for (unsigned int i = 0; i < 4; i++)
83 d.v[i] = (int) ((v >> (i*8))&0xFF) - (int) ((o.v >> (i*8))&0xFF);
84 return d;
85 }
86
87 uint32_t v;
88 };
89
90 struct image_t
91 {
92 public:
93
image_timage_t94 image_t (unsigned int width_,
95 unsigned int height_,
96 const uint32_t *data_,
97 unsigned int stride_) :
98 width (width_),
99 height (height_),
100 own_data (false),
101 data ((color_t *) data_),
102 stride (stride_) {}
image_timage_t103 image_t (unsigned int width_,
104 unsigned int height_) :
105 width (width_),
106 height (height_),
107 own_data (true),
108 data ((color_t *) malloc (sizeof (data[0]) * width * height)),
109 stride (width) {}
~image_timage_t110 ~image_t ()
111 { if (own_data) free (data); }
112
operator ()image_t113 color_t &operator () (unsigned int x, unsigned int y)
114 { return data[x + y * stride]; }
115
operator ()image_t116 color_t operator () (unsigned int x, unsigned int y) const
117 { return data[x + y * stride]; }
118
119 void
copy_sub_imageimage_t120 copy_sub_image (const image_t &s,
121 unsigned int x, unsigned int y,
122 unsigned int w, unsigned int h)
123 {
124 assert (x < width);
125 assert (y < height);
126 for (unsigned int row = 0; row < h; row++) {
127 color_t *p = data + x + hb_min (y + row, height - 1) * stride;
128 color_t *q = s.data + row * s.stride;
129 if (x + w <= width)
130 for (unsigned int col = 0; col < w; col++)
131 *q++ = *p++;
132 else {
133 unsigned int limit = width - x;
134 for (unsigned int col = 0; col < limit; col++)
135 *q++ = *p++;
136 p--;
137 for (unsigned int col = limit; col < w; col++)
138 *q++ = *p;
139 }
140 }
141 }
142
143 const unsigned int width;
144 const unsigned int height;
145
146 private:
147 bool own_data;
148 color_t * const data;
149 const unsigned int stride;
150 };
151
152 struct biimage_t
153 {
154 public:
155
biimage_tbiimage_t156 biimage_t (unsigned int width, unsigned int height) :
157 width (width),
158 height (height),
159 bg (0), fg (0), unicolor (true),
160 data ((uint8_t *) malloc (sizeof (data[0]) * width * height)) {}
~biimage_tbiimage_t161 ~biimage_t ()
162 { free (data); }
163
setbiimage_t164 void set (const image_t &image)
165 {
166 assert (image.width == width);
167 assert (image.height == height);
168 int freq[8] = {0};
169 for (unsigned int y = 0; y < height; y++)
170 for (unsigned int x = 0; x < width; x++) {
171 color_t c = image (x, y);
172 freq[c.to_ansi ()]++;
173 }
174 bg = 0;
175 for (unsigned int i = 1; i < 8; i++)
176 if (freq[bg] < freq[i])
177 bg = i;
178 fg = 8;
179 for (unsigned int i = 0; i < 8; i++)
180 if (i != bg && (fg == 8 || freq[fg] < freq[i]))
181 fg = i;
182 if (freq[fg] == 0) {
183 fg = bg;
184 unicolor = true;
185 }
186 else
187 unicolor = false;
188
189 /* Set the data... */
190
191 if (unicolor) {
192 memset (data, 0, sizeof (data[0]) * width * height);
193 return;
194 }
195
196 color_t bgc = color_t::from_ansi (bg);
197 color_t fgc = color_t::from_ansi (fg);
198 color_diff_t diff = fgc.diff (bgc);
199 double dd = sqrt (diff.dot (diff));
200 for (unsigned int y = 0; y < height; y++)
201 for (unsigned int x = 0; x < width; x++) {
202 double d = sqrt (diff.dot (image (x, y).diff (bgc)));
203 (*this)(x, y) = d <= 0 ? 0 : d >= dd ? 255 : lround (d / dd * 255.);
204 }
205 }
206
operator ()biimage_t207 uint8_t &operator () (unsigned int x, unsigned int y)
208 { return data[x + y * width]; }
209
operator ()biimage_t210 uint8_t operator () (unsigned int x, unsigned int y) const
211 { return data[x + y * width]; }
212
213 const unsigned int width;
214 const unsigned int height;
215 unsigned int bg;
216 unsigned int fg;
217 bool unicolor;
218
219 private:
220 uint8_t * const data;
221 };
222
223 static const char *
block_best(const biimage_t & bi,bool * inverse)224 block_best (const biimage_t &bi, bool *inverse)
225 {
226 assert (bi.width <= CELL_W);
227 assert (bi.height <= CELL_H);
228
229 unsigned int score = UINT_MAX;
230 unsigned int row_sum[CELL_H] = {0};
231 unsigned int col_sum[CELL_W] = {0};
232 unsigned int row_sum_i[CELL_H] = {0};
233 unsigned int col_sum_i[CELL_W] = {0};
234 unsigned int quad[2][2] = {{0}};
235 unsigned int quad_i[2][2] = {{0}};
236 unsigned int total = 0;
237 unsigned int total_i = 0;
238 for (unsigned int y = 0; y < bi.height; y++)
239 for (unsigned int x = 0; x < bi.width; x++) {
240 unsigned int c = bi (x, y);
241 unsigned int c_i = 255 - c;
242 row_sum[y] += c;
243 row_sum_i[y] += c_i;
244 col_sum[x] += c;
245 col_sum_i[x] += c_i;
246 quad[2 * y / bi.height][2 * x / bi.width] += c;
247 quad_i[2 * y / bi.height][2 * x / bi.width] += c_i;
248 total += c;
249 total_i += c_i;
250 }
251
252 /* Make the sums cumulative */
253 for (unsigned int i = 1; i < bi.height; i++) {
254 row_sum[i] += row_sum[i - 1];
255 row_sum_i[i] += row_sum_i[i - 1];
256 }
257 for (unsigned int i = 1; i < bi.width; i++) {
258 col_sum[i] += col_sum[i - 1];
259 col_sum_i[i] += col_sum_i[i - 1];
260 }
261
262 const char *best_c = " ";
263
264 /* Maybe empty is better! */
265 if (total < score) {
266 score = total;
267 *inverse = false;
268 best_c = " ";
269 }
270 /* Maybe full is better! */
271 if (total_i < score) {
272 score = total_i;
273 *inverse = true;
274 best_c = " ";
275 }
276
277 /* Find best lower line */
278 if (1) {
279 unsigned int best_s = UINT_MAX;
280 bool best_inv = false;
281 int best_i = 0;
282 for (unsigned int i = 0; i < bi.height - 1; i++)
283 {
284 unsigned int s;
285 s = row_sum[i] + total_i - row_sum_i[i];
286 if (s < best_s) {
287 best_s = s;
288 best_i = i;
289 best_inv = false;
290 }
291 s = row_sum_i[i] + total - row_sum[i];
292 if (s < best_s) {
293 best_s = s;
294 best_i = i;
295 best_inv = true;
296 }
297 }
298 if (best_s < score) {
299 static const char *lower[7] = {"▁", "▂", "▃", "▄", "▅", "▆", "▇"};
300 unsigned int which = lround ((double) ((best_i + 1) * 8) / bi.height);
301 if (1 <= which && which <= 7) {
302 score = best_s;
303 *inverse = best_inv;
304 best_c = lower[7 - which];
305 }
306 }
307 }
308
309 /* Find best left line */
310 if (1) {
311 unsigned int best_s = UINT_MAX;
312 bool best_inv = false;
313 int best_i = 0;
314 for (unsigned int i = 0; i < bi.width - 1; i++)
315 {
316 unsigned int s;
317 s = col_sum[i] + total_i - col_sum_i[i];
318 if (s < best_s) {
319 best_s = s;
320 best_i = i;
321 best_inv = true;
322 }
323 s = col_sum_i[i] + total - col_sum[i];
324 if (s < best_s) {
325 best_s = s;
326 best_i = i;
327 best_inv = false;
328 }
329 }
330 if (best_s < score) {
331 static const char *left [7] = {"▏", "▎", "▍", "▌", "▋", "▊", "▉"};
332 unsigned int which = lround ((double) ((best_i + 1) * 8) / bi.width);
333 if (1 <= which && which <= 7) {
334 score = best_s;
335 *inverse = best_inv;
336 best_c = left[which - 1];
337 }
338 }
339 }
340
341 /* Find best quadrant */
342 if (1) {
343 unsigned int q = 0;
344 unsigned int qs = 0;
345 for (unsigned int i = 0; i < 2; i++)
346 for (unsigned int j = 0; j < 2; j++)
347 if (quad[i][j] > quad_i[i][j]) {
348 q += 1 << (2 * i + j);
349 qs += quad_i[i][j];
350 } else
351 qs += quad[i][j];
352 if (qs < score) {
353 const char *c = nullptr;
354 bool inv = false;
355 switch (q) {
356 case 1: c = "▟"; inv = true; break;
357 case 2: c = "▙"; inv = true; break;
358 case 4: c = "▖"; inv = false; break;
359 case 6: c = "▞"; inv = false; break;
360 case 7: c = "▛"; inv = false; break;
361 case 8: c = "▗"; inv = false; break;
362 case 9: c = "▚"; inv = false; break;
363 case 11: c = "▜"; inv = false; break;
364 case 13: c = "▙"; inv = false; break;
365 case 14: c = "▟"; inv = false; break;
366 }
367 if (c) {
368 score = qs;
369 *inverse = inv;
370 best_c = c;
371 }
372 }
373 }
374
375 return best_c;
376 }
377
378 static inline void
ansi_print_image_rgb24(const uint32_t * data,unsigned int width,unsigned int height,unsigned int stride)379 ansi_print_image_rgb24 (const uint32_t *data,
380 unsigned int width,
381 unsigned int height,
382 unsigned int stride)
383 {
384 image_t image (width, height, data, stride);
385
386 unsigned int rows = (height + CELL_H - 1) / CELL_H;
387 unsigned int cols = (width + CELL_W - 1) / CELL_W;
388 image_t cell (CELL_W, CELL_H);
389 biimage_t bi (CELL_W, CELL_H);
390 unsigned int last_bg = -1, last_fg = -1;
391 for (unsigned int row = 0; row < rows; row++) {
392 for (unsigned int col = 0; col < cols; col++) {
393 image.copy_sub_image (cell, col * CELL_W, row * CELL_H, CELL_W, CELL_H);
394 bi.set (cell);
395 if (bi.unicolor) {
396 if (last_bg != bi.bg) {
397 printf ("%c[%dm", ESC_E, 40 + bi.bg);
398 last_bg = bi.bg;
399 }
400 printf (" ");
401 } else {
402 /* Figure out the closest character to the biimage */
403 bool inverse = false;
404 const char *c = block_best (bi, &inverse);
405 if (inverse) {
406 if (last_bg != bi.fg || last_fg != bi.bg) {
407 printf ("%c[%d;%dm", ESC_E, 30 + bi.bg, 40 + bi.fg);
408 last_bg = bi.fg;
409 last_fg = bi.bg;
410 }
411 } else {
412 if (last_bg != bi.bg || last_fg != bi.fg) {
413 printf ("%c[%d;%dm", ESC_E, 40 + bi.bg, 30 + bi.fg);
414 last_bg = bi.bg;
415 last_fg = bi.fg;
416 }
417 }
418 printf ("%s", c);
419 }
420 }
421 printf ("%c[0m\n", ESC_E); /* Reset */
422 last_bg = last_fg = -1;
423 }
424 }
425
426 #endif
427