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/*
* Copyright © 2012 Google, Inc.
*
* This is part of HarfBuzz, a text shaping library.
*
* Permission is hereby granted, without written agreement and without
* license or royalty fees, to use, copy, modify, and distribute this
* software and its documentation for any purpose, provided that the
* above copyright notice and the following two paragraphs appear in
* all copies of this software.
*
* IN NO EVENT SHALL THE COPYRIGHT HOLDER BE LIABLE TO ANY PARTY FOR
* DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES
* ARISING OUT OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN
* IF THE COPYRIGHT HOLDER HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH
* DAMAGE.
*
* THE COPYRIGHT HOLDER SPECIFICALLY DISCLAIMS ANY WARRANTIES, INCLUDING,
* BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
* FITNESS FOR A PARTICULAR PURPOSE. THE SOFTWARE PROVIDED HEREUNDER IS
* ON AN "AS IS" BASIS, AND THE COPYRIGHT HOLDER HAS NO OBLIGATION TO
* PROVIDE MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS.
*
* Google Author(s): Behdad Esfahbod
*/
#ifndef ANSI_PRINT_HH
#define ANSI_PRINT_HH
#include "hb.hh"
#include <cairo.h>
#include <assert.h>
#include <stdlib.h>
#include <stddef.h>
#include <string.h>
#include <math.h>
#if defined (_MSC_VER) && (_MSC_VER < 1800)
static inline long int
lround (double x)
{
if (x >= 0)
return floor (x + 0.5);
else
return ceil (x - 0.5);
}
#endif
#define CELL_W 8
#define CELL_H (2 * CELL_W)
struct color_diff_t
{
int dot (const color_diff_t &o)
{ return v[0]*o.v[0] + v[1]*o.v[1] + v[2]*o.v[2] + v[3]*o.v[3]; }
int v[4];
};
struct color_t
{
static color_t from_ansi (unsigned int x)
{
color_t c = {(0xFFu<<24) | ((0xFFu*(x&1))<<16) | ((0xFFu*((x >> 1)&1))<<8) | (0xFFu*((x >> 2)&1))};
return c;
}
unsigned int to_ansi ()
{
return ((v >> 23) & 1) | ((v >> 14)&2) | ((v >> 5)&4);
}
color_diff_t diff (const color_t &o)
{
color_diff_t d;
for (unsigned int i = 0; i < 4; i++)
d.v[i] = (int) ((v >> (i*8))&0xFF) - (int) ((o.v >> (i*8))&0xFF);
return d;
}
uint32_t v;
};
struct image_t
{
public:
image_t (unsigned int width_,
unsigned int height_,
const uint32_t *data_,
unsigned int stride_) :
width (width_),
height (height_),
own_data (false),
data ((color_t *) data_),
stride (stride_) {}
image_t (unsigned int width_,
unsigned int height_) :
width (width_),
height (height_),
own_data (true),
data ((color_t *) malloc (sizeof (data[0]) * width * height)),
stride (width) {}
~image_t ()
{ if (own_data) free (data); }
color_t &operator () (unsigned int x, unsigned int y)
{ return data[x + y * stride]; }
color_t operator () (unsigned int x, unsigned int y) const
{ return data[x + y * stride]; }
void
copy_sub_image (const image_t &s,
unsigned int x, unsigned int y,
unsigned int w, unsigned int h)
{
assert (x < width);
assert (y < height);
for (unsigned int row = 0; row < h; row++) {
color_t *p = data + x + hb_min (y + row, height - 1) * stride;
color_t *q = s.data + row * s.stride;
if (x + w <= width)
for (unsigned int col = 0; col < w; col++)
*q++ = *p++;
else {
unsigned int limit = width - x;
for (unsigned int col = 0; col < limit; col++)
*q++ = *p++;
p--;
for (unsigned int col = limit; col < w; col++)
*q++ = *p;
}
}
}
const unsigned int width;
const unsigned int height;
private:
bool own_data;
color_t * const data;
const unsigned int stride;
};
struct biimage_t
{
public:
biimage_t (unsigned int width, unsigned int height) :
width (width),
height (height),
bg (0), fg (0), unicolor (true),
data ((uint8_t *) malloc (sizeof (data[0]) * width * height)) {}
~biimage_t ()
{ free (data); }
void set (const image_t &image)
{
assert (image.width == width);
assert (image.height == height);
int freq[8] = {0};
for (unsigned int y = 0; y < height; y++)
for (unsigned int x = 0; x < width; x++) {
color_t c = image (x, y);
freq[c.to_ansi ()]++;
}
bg = 0;
for (unsigned int i = 1; i < 8; i++)
if (freq[bg] < freq[i])
bg = i;
fg = 8;
for (unsigned int i = 0; i < 8; i++)
if (i != bg && (fg == 8 || freq[fg] < freq[i]))
fg = i;
if (freq[fg] == 0) {
fg = bg;
unicolor = true;
}
else
unicolor = false;
/* Set the data... */
if (unicolor) {
memset (data, 0, sizeof (data[0]) * width * height);
return;
}
color_t bgc = color_t::from_ansi (bg);
color_t fgc = color_t::from_ansi (fg);
color_diff_t diff = fgc.diff (bgc);
double dd = sqrt (diff.dot (diff));
for (unsigned int y = 0; y < height; y++)
for (unsigned int x = 0; x < width; x++) {
double d = sqrt (diff.dot (image (x, y).diff (bgc)));
(*this)(x, y) = d <= 0 ? 0 : d >= dd ? 255 : lround (d / dd * 255.);
}
}
uint8_t &operator () (unsigned int x, unsigned int y)
{ return data[x + y * width]; }
uint8_t operator () (unsigned int x, unsigned int y) const
{ return data[x + y * width]; }
const unsigned int width;
const unsigned int height;
unsigned int bg;
unsigned int fg;
bool unicolor;
private:
uint8_t * const data;
};
static const char *
block_best (const biimage_t &bi, bool *inverse)
{
assert (bi.width <= CELL_W);
assert (bi.height <= CELL_H);
unsigned int score = UINT_MAX;
unsigned int row_sum[CELL_H] = {0};
unsigned int col_sum[CELL_W] = {0};
unsigned int row_sum_i[CELL_H] = {0};
unsigned int col_sum_i[CELL_W] = {0};
unsigned int quad[2][2] = {{0}};
unsigned int quad_i[2][2] = {{0}};
unsigned int total = 0;
unsigned int total_i = 0;
for (unsigned int y = 0; y < bi.height; y++)
for (unsigned int x = 0; x < bi.width; x++) {
unsigned int c = bi (x, y);
unsigned int c_i = 255 - c;
row_sum[y] += c;
row_sum_i[y] += c_i;
col_sum[x] += c;
col_sum_i[x] += c_i;
quad[2 * y / bi.height][2 * x / bi.width] += c;
quad_i[2 * y / bi.height][2 * x / bi.width] += c_i;
total += c;
total_i += c_i;
}
/* Make the sums cumulative */
for (unsigned int i = 1; i < bi.height; i++) {
row_sum[i] += row_sum[i - 1];
row_sum_i[i] += row_sum_i[i - 1];
}
for (unsigned int i = 1; i < bi.width; i++) {
col_sum[i] += col_sum[i - 1];
col_sum_i[i] += col_sum_i[i - 1];
}
const char *best_c = " ";
/* Maybe empty is better! */
if (total < score) {
score = total;
*inverse = false;
best_c = " ";
}
/* Maybe full is better! */
if (total_i < score) {
score = total_i;
*inverse = true;
best_c = " ";
}
/* Find best lower line */
if (1) {
unsigned int best_s = UINT_MAX;
bool best_inv = false;
int best_i = 0;
for (unsigned int i = 0; i < bi.height - 1; i++)
{
unsigned int s;
s = row_sum[i] + total_i - row_sum_i[i];
if (s < best_s) {
best_s = s;
best_i = i;
best_inv = false;
}
s = row_sum_i[i] + total - row_sum[i];
if (s < best_s) {
best_s = s;
best_i = i;
best_inv = true;
}
}
if (best_s < score) {
static const char *lower[7] = {"▁", "▂", "▃", "▄", "▅", "▆", "▇"};
unsigned int which = lround ((double) ((best_i + 1) * 8) / bi.height);
if (1 <= which && which <= 7) {
score = best_s;
*inverse = best_inv;
best_c = lower[7 - which];
}
}
}
/* Find best left line */
if (1) {
unsigned int best_s = UINT_MAX;
bool best_inv = false;
int best_i = 0;
for (unsigned int i = 0; i < bi.width - 1; i++)
{
unsigned int s;
s = col_sum[i] + total_i - col_sum_i[i];
if (s < best_s) {
best_s = s;
best_i = i;
best_inv = true;
}
s = col_sum_i[i] + total - col_sum[i];
if (s < best_s) {
best_s = s;
best_i = i;
best_inv = false;
}
}
if (best_s < score) {
static const char *left [7] = {"▏", "▎", "▍", "▌", "▋", "▊", "▉"};
unsigned int which = lround ((double) ((best_i + 1) * 8) / bi.width);
if (1 <= which && which <= 7) {
score = best_s;
*inverse = best_inv;
best_c = left[which - 1];
}
}
}
/* Find best quadrant */
if (1) {
unsigned int q = 0;
unsigned int qs = 0;
for (unsigned int i = 0; i < 2; i++)
for (unsigned int j = 0; j < 2; j++)
if (quad[i][j] > quad_i[i][j]) {
q += 1 << (2 * i + j);
qs += quad_i[i][j];
} else
qs += quad[i][j];
if (qs < score) {
const char *c = nullptr;
bool inv = false;
switch (q) {
case 1: c = "▟"; inv = true; break;
case 2: c = "▙"; inv = true; break;
case 4: c = "▖"; inv = false; break;
case 6: c = "▞"; inv = false; break;
case 7: c = "▛"; inv = false; break;
case 8: c = "▗"; inv = false; break;
case 9: c = "▚"; inv = false; break;
case 11: c = "▜"; inv = false; break;
case 13: c = "▙"; inv = false; break;
case 14: c = "▟"; inv = false; break;
}
if (c) {
score = qs;
*inverse = inv;
best_c = c;
}
}
}
return best_c;
}
static inline void
ansi_print_image_rgb24 (const uint32_t *data,
unsigned int width,
unsigned int height,
unsigned int stride,
cairo_write_func_t write_func,
void *closure)
{
image_t image (width, height, data, stride);
unsigned int rows = (height + CELL_H - 1) / CELL_H;
unsigned int cols = (width + CELL_W - 1) / CELL_W;
image_t cell (CELL_W, CELL_H);
biimage_t bi (CELL_W, CELL_H);
unsigned int last_bg = -1, last_fg = -1;
for (unsigned int row = 0; row < rows; row++)
{
for (unsigned int col = 0; col < cols; col++)
{
image.copy_sub_image (cell, col * CELL_W, row * CELL_H, CELL_W, CELL_H);
bi.set (cell);
if (bi.unicolor)
{
if (last_bg != bi.bg)
{
char buf[] = "\033[40m";
buf[3] += bi.bg;
write_func (closure, (unsigned char *) buf, 5);
last_bg = bi.bg;
}
write_func (closure, (unsigned char *) " ", 1);
}
else
{
/* Figure out the closest character to the biimage */
bool inverse = false;
const char *c = block_best (bi, &inverse);
if (inverse)
{
if (last_bg != bi.fg || last_fg != bi.bg)
{
char buf[] = "\033[30;40m";
buf[3] += bi.bg;
buf[6] += bi.fg;
write_func (closure, (unsigned char *) buf, 8);
last_bg = bi.fg;
last_fg = bi.bg;
}
}
else
{
if (last_bg != bi.bg || last_fg != bi.fg)
{
char buf[] = "\033[40;30m";
buf[3] += bi.bg;
buf[6] += bi.fg;
write_func (closure, (unsigned char *) buf, 8);
last_bg = bi.bg;
last_fg = bi.fg;
}
}
write_func (closure, (unsigned char *) c, strlen (c));
}
}
write_func (closure, (unsigned char *) "\033[0m\n", 5); /* Reset */
last_bg = last_fg = -1;
}
}
#endif