txtwin_fbpan.c

   1 #include <errno.h>
   2 #include <fcntl.h>
   3 #include <locale.h>
   4 #include <poll.h>
   5 #include <stdio.h>
   6 #include <stdlib.h>
   7 #include <string.h>
   8 #include <sys/wait.h>
   9 #include <pty.h>
  10
  11 #include <glib.h>
  12 #include <pango/pango.h>
  13 #include <pango/pangoft2.h>
  14
  15 #include "draw.h"
  16 #include "util.h"
  17
  18 #define MAXTEXT                 (1 << 20)
  19 #define DPI                     196
  20 #define PAGESTEPS               8
  21 #define CTRLKEY(x)              ((x) - 96)
  22
  23 struct txtwin {
  24         int n;
  25 };
  26
  27 static struct {
  28         char name[1 << 4];
  29         char desc[1 << 8];
  30 } tags[1 << 4] = {
  31         {"default", "<span size=\"xx-small\">"}
  32 };
  33 static int ntags = 1;
  34
  35 static PangoContext *context;
  36 static int width = 1;
  37 static int height = 1;
  38 static PangoFontMap *fontmap;
  39 static FT_Bitmap *bitmap;
  40 static char text[MAXTEXT];
  41 static char *pos = text;
  42
  43 static FT_Bitmap *create_bitmap(int width, int height)
  44 {
  45         FT_Bitmap *bitmap = g_slice_new(FT_Bitmap);
  46         bitmap->width = width;
  47         bitmap->pitch = (bitmap->width + 3) & ~3;
  48         bitmap->rows = height;
  49         bitmap->buffer = g_malloc(bitmap->pitch * bitmap->rows);
  50         bitmap->num_grays = 256;
  51         bitmap->pixel_mode = ft_pixel_mode_grays;
  52         memset(bitmap->buffer, 0, bitmap->pitch * bitmap->rows);
  53         return bitmap;
  54 }
  55
  56 static void destroy_bitmap(FT_Bitmap *bitmap)
  57 {
  58         g_free(bitmap->buffer);
  59         g_slice_free(FT_Bitmap, bitmap);
  60 }
  61
  62 #define COLORMERGE(f, b, c)             ((b) + (((f) - (b)) * (c) >> 8u))
  63
  64 static void view_write(int sr)
  65 {
  66         int r, c;
  67         fbval_t buf[1 << 14];
  68         int nr = MIN(height - sr, fb_rows());
  69         int nc = MIN(width, fb_cols());
  70         for (r = 0; r < nr; r++) {
  71                 for (c = 0; c < nc; c++) {
  72                         int v = bitmap->buffer[(sr + r) * bitmap->pitch + c];
  73                         int r = COLORMERGE(0xd5, 0x00, 255 - v);
  74                         int g = COLORMERGE(0xdd, 0x00, 255 - v);
  75                         int b = COLORMERGE(0xff, 0x00, 255 - v);
  76                         buf[c] = fb_color(r, g, b);
  77                 }
  78                 fb_set(r, 0, buf, width);
  79         }
  80 }
  81
  82 static PangoLayout *make_layout(PangoContext *context, char *text, double size)
  83 {
  84         static PangoFontDescription *font_description;
  85         PangoLayout *layout = pango_layout_new(context);
  86         pango_layout_set_markup(layout, text, -1);
  87         pango_layout_set_wrap(layout, PANGO_WRAP_WORD_CHAR);
  88         pango_layout_set_width(layout, fb_cols() << 10);
  89         pango_layout_set_height(layout, -1);
  90         pango_layout_set_alignment(layout, PANGO_ALIGN_RIGHT);
  91         pango_layout_set_font_description(layout, font_description);
  92         pango_font_description_free(font_description);
  93         return layout;
  94 }
  95
  96 static void do_output(PangoContext *context, char *text)
  97 {
  98         PangoLayout *layout;
  99         PangoRectangle logical_rect;
 100         pango_context_set_language(context, pango_language_get_default());
 101         pango_context_set_base_dir(context, PANGO_DIRECTION_RTL);
 102         layout = make_layout(context, text, -1);
 103         pango_layout_get_pixel_extents(layout, NULL, &logical_rect);
 104         pango_ft2_render_layout(bitmap, layout, 0, 0);
 105         width = MAX(width, MAX(logical_rect.x + logical_rect.width,
 106                         PANGO_PIXELS(pango_layout_get_width(layout))));
 107         height = MAX(logical_rect.y + logical_rect.height,
 108                 PANGO_PIXELS(pango_layout_get_height(layout)));
 109         g_object_unref(layout);
 110 }
 111
 112 static int readkey(void)
 113 {
 114         char b;
 115         if (read(STDIN_FILENO, &b, 1) <= 0)
 116                 return -1;
 117         return b;
 118 }
 119
 120 void txtwin_append(struct txtwin *tw, char *s, char *tag)
 121 {
 122         int i;
 123         int t = 0;
 124         for (i = 0; i < ntags; i++)
 125                 if (tag && !strcmp(tag, tags[i].name))
 126                         t = i;
 127         snprintf(pos, MAXTEXT - (pos - text),
 128                  "%s%s</span>", tags[t].desc, s);
 129         pos = strchr(pos, '\0');
 130 }
 131
 132 void txtwin_tag(struct txtwin *tw, char *name, char *fg, char *bg, char *font)
 133 {
 134         strcpy(tags[ntags].name, name);
 135         snprintf(tags[ntags].desc, sizeof(tags[ntags].desc),
 136                 "<span font=\"%s\">", font);
 137         ntags++;
 138 }
 139
 140 void txtwin_loop(struct txtwin *tw)
 141 {
 142         int step = fb_rows() / PAGESTEPS;
 143         int head = 0;
 144         int c;
 145         struct termios oldtermios, termios;
 146         tcgetattr(STDIN_FILENO, &termios);
 147         oldtermios = termios;
 148         cfmakeraw(&termios);
 149         tcsetattr(STDIN_FILENO, TCSAFLUSH, &termios);
 150         bitmap = create_bitmap(width, height);
 151         do_output(context, text);
 152         destroy_bitmap(bitmap);
 153         bitmap = create_bitmap(width, height);
 154         do_output(context, text);
 155         view_write(head);
 156         while ((c = readkey()) != -1) {
 157                 switch (c) {
 158                 case 'j':
 159                         head += step;
 160                         break;
 161                 case 'k':
 162                         head -= step;
 163                         break;
 164                 case CTRLKEY('f'):
 165                 case ' ':
 166                         head += fb_rows() - step;
 167                         break;
 168                 case CTRLKEY('b'):
 169                         head -= fb_rows() - step;
 170                         break;
 171                 case 'G':
 172                         head = height - fb_rows();
 173                         break;
 174                 case 'q':
 175                         tcsetattr(STDIN_FILENO, 0, &oldtermios);
 176                         return;
 177                 }
 178                 head = MAX(0, MIN(head, height - fb_rows()));
 179                 view_write(head);
 180         }
 181 }
 182
 183 void txtwin_gtk_init(int argc, char **argv)
 184 {
 185         char *clear = "\x1b[2J\x1b[H";
 186         char *msg = "\t\t\t\t***FBPAN***\n";
 187         char *hide = "\x1b[?25l";
 188         g_type_init();
 189         g_set_prgname("fbpan");
 190         setlocale(LC_ALL, "");
 191         write(STDIN_FILENO, clear, strlen(clear));
 192         write(STDIN_FILENO, msg, strlen(msg));
 193         write(STDIN_FILENO, hide, strlen(hide));
 194         fb_init();
 195 }
 196
 197 struct txtwin *txtwin_alloc() {
 198         fontmap = pango_ft2_font_map_new();
 199         pango_ft2_font_map_set_resolution(PANGO_FT2_FONT_MAP(fontmap), DPI, DPI);
 200         context = pango_font_map_create_context(PANGO_FONT_MAP(fontmap));
 201         return NULL;
 202 }
 203
 204 void txtwin_free(struct txtwin *tw)
 205 {
 206         char *show = "\x1b[?25h";
 207         fb_free();
 208         destroy_bitmap(bitmap);
 209         g_object_unref(context);
 210         g_object_unref(fontmap);
 211         write(STDIN_FILENO, show, strlen(show));
 212 }