txtwin_fbpan.c

   1 #include <ctype.h>
   2 #include <errno.h>
   3 #include <fcntl.h>
   4 #include <locale.h>
   5 #include <poll.h>
   6 #include <stdio.h>
   7 #include <stdlib.h>
   8 #include <string.h>
   9 #include <sys/wait.h>
  10 #include <pty.h>
  11
  12 #include <glib.h>
  13 #include <pango/pango.h>
  14 #include <pango/pangoft2.h>
  15
  16 #include "draw.h"
  17 #include "util.h"
  18
  19 #define MAXTEXT                 (1 << 20)
  20 #define DPI                     196
  21 #define PAGESTEPS               8
  22 #define CTRLKEY(x)              ((x) - 96)
  23
  24 struct txtwin {
  25         int n;
  26 };
  27
  28 static struct {
  29         char name[1 << 4];
  30         char desc[1 << 8];
  31 } tags[1 << 4] = {
  32         {"default", "<span size=\"xx-small\">"}
  33 };
  34 static int ntags = 1;
  35
  36 static PangoContext *context;
  37 static int width = 1;
  38 static int height = 1;
  39 static PangoFontMap *fontmap;
  40 static FT_Bitmap *bitmap;
  41 static char text[MAXTEXT];
  42 static char *pos = text;
  43 static int count;
  44
  45 static FT_Bitmap *create_bitmap(int width, int height)
  46 {
  47         FT_Bitmap *bitmap = g_slice_new(FT_Bitmap);
  48         bitmap->width = width;
  49         bitmap->pitch = (bitmap->width + 3) & ~3;
  50         bitmap->rows = height;
  51         bitmap->buffer = g_malloc(bitmap->pitch * bitmap->rows);
  52         bitmap->num_grays = 256;
  53         bitmap->pixel_mode = ft_pixel_mode_grays;
  54         memset(bitmap->buffer, 0, bitmap->pitch * bitmap->rows);
  55         return bitmap;
  56 }
  57
  58 static void destroy_bitmap(FT_Bitmap *bitmap)
  59 {
  60         g_free(bitmap->buffer);
  61         g_slice_free(FT_Bitmap, bitmap);
  62 }
  63
  64 #define COLORMERGE(f, b, c)             ((b) + (((f) - (b)) * (c) >> 8u))
  65
  66 static void view_write(int sr)
  67 {
  68         int r, c;
  69         fbval_t buf[1 << 14];
  70         int nr = MIN(height - sr, fb_rows());
  71         int nc = MIN(width, fb_cols());
  72         for (r = 0; r < nr; r++) {
  73                 for (c = 0; c < nc; c++) {
  74                         int v = bitmap->buffer[(sr + r) * bitmap->pitch + c];
  75                         int r = COLORMERGE(0xd5, 0x00, 255 - v);
  76                         int g = COLORMERGE(0xdd, 0x00, 255 - v);
  77                         int b = COLORMERGE(0xff, 0x00, 255 - v);
  78                         buf[c] = fb_color(r, g, b);
  79                 }
  80                 fb_set(r, 0, buf, width);
  81         }
  82 }
  83
  84 static PangoLayout *make_layout(PangoContext *context, char *text, double size)
  85 {
  86         static PangoFontDescription *font_description;
  87         PangoLayout *layout = pango_layout_new(context);
  88         pango_layout_set_markup(layout, text, -1);
  89         pango_layout_set_wrap(layout, PANGO_WRAP_WORD_CHAR);
  90         pango_layout_set_width(layout, fb_cols() << 10);
  91         pango_layout_set_height(layout, -1);
  92         pango_layout_set_alignment(layout, PANGO_ALIGN_RIGHT);
  93         pango_layout_set_font_description(layout, font_description);
  94         pango_font_description_free(font_description);
  95         return layout;
  96 }
  97
  98 static void do_output(PangoContext *context, char *text)
  99 {
 100         PangoLayout *layout;
 101         PangoRectangle logical_rect;
 102         pango_context_set_language(context, pango_language_get_default());
 103         pango_context_set_base_dir(context, PANGO_DIRECTION_RTL);
 104         layout = make_layout(context, text, -1);
 105         pango_layout_get_pixel_extents(layout, NULL, &logical_rect);
 106         pango_ft2_render_layout(bitmap, layout, 0, 0);
 107         width = MAX(width, MAX(logical_rect.x + logical_rect.width,
 108                         PANGO_PIXELS(pango_layout_get_width(layout))));
 109         height = MAX(logical_rect.y + logical_rect.height,
 110                 PANGO_PIXELS(pango_layout_get_height(layout)));
 111         g_object_unref(layout);
 112 }
 113
 114 static int readkey(void)
 115 {
 116         char b;
 117         if (read(STDIN_FILENO, &b, 1) <= 0)
 118                 return -1;
 119         return b;
 120 }
 121
 122 void txtwin_append(struct txtwin *tw, char *s, char *tag)
 123 {
 124         int i;
 125         int t = 0;
 126         for (i = 0; i < ntags; i++)
 127                 if (tag && !strcmp(tag, tags[i].name))
 128                         t = i;
 129         snprintf(pos, MAXTEXT - (pos - text),
 130                  "%s%s</span>", tags[t].desc, s);
 131         pos = strchr(pos, '\0');
 132 }
 133
 134 void txtwin_tag(struct txtwin *tw, char *name, char *fg, char *bg, char *font)
 135 {
 136         strcpy(tags[ntags].name, name);
 137         snprintf(tags[ntags].desc, sizeof(tags[ntags].desc),
 138                 "<span font=\"%s\">", font);
 139         ntags++;
 140 }
 141
 142 static int getcount(int def)
 143 {
 144         int result = count ? count : def;
 145         count = 0;
 146         return result;
 147 }
 148
 149 void txtwin_loop(struct txtwin *tw)
 150 {
 151         int step = fb_rows() / PAGESTEPS;
 152         int head = 0;
 153         int c;
 154         struct termios oldtermios, termios;
 155         tcgetattr(STDIN_FILENO, &termios);
 156         oldtermios = termios;
 157         cfmakeraw(&termios);
 158         tcsetattr(STDIN_FILENO, TCSAFLUSH, &termios);
 159         bitmap = create_bitmap(width, height);
 160         do_output(context, text);
 161         destroy_bitmap(bitmap);
 162         bitmap = create_bitmap(width, height);
 163         do_output(context, text);
 164         view_write(head);
 165         while ((c = readkey()) != -1) {
 166                 switch (c) {
 167                 case 'j':
 168                         head += step * getcount(1);
 169                         break;
 170                 case 'k':
 171                         head -= step * getcount(1);
 172                         break;
 173                 case CTRLKEY('f'):
 174                 case ' ':
 175                         head += fb_rows() * getcount(1) - step;
 176                         break;
 177                 case CTRLKEY('b'):
 178                         head -= fb_rows() * getcount(1) - step;
 179                         break;
 180                 case 'G':
 181                         if (getcount(0))
 182                                 head = 0;
 183                         else
 184                                 head = height - fb_rows();
 185                         break;
 186                 case 27:
 187                         count = 0;
 188                         break;
 189                 case 'q':
 190                         tcsetattr(STDIN_FILENO, 0, &oldtermios);
 191                         return;
 192                 default:
 193                         if (isdigit(c))
 194                                 count = count * 10 + 'c' - '0';
 195                 }
 196                 head = MAX(0, MIN(head, height - fb_rows()));
 197                 view_write(head);
 198         }
 199 }
 200
 201 void txtwin_gtk_init(int argc, char **argv)
 202 {
 203         char *clear = "\x1b[2J\x1b[H";
 204         char *msg = "\t\t\t\t***FBPAN***\n";
 205         char *hide = "\x1b[?25l";
 206         g_type_init();
 207         g_set_prgname("fbpan");
 208         setlocale(LC_ALL, "");
 209         write(STDIN_FILENO, clear, strlen(clear));
 210         write(STDIN_FILENO, msg, strlen(msg));
 211         write(STDIN_FILENO, hide, strlen(hide));
 212         fb_init();
 213 }
 214
 215 struct txtwin *txtwin_alloc() {
 216         fontmap = pango_ft2_font_map_new();
 217         pango_ft2_font_map_set_resolution(PANGO_FT2_FONT_MAP(fontmap), DPI, DPI);
 218         context = pango_font_map_create_context(PANGO_FONT_MAP(fontmap));
 219         return NULL;
 220 }
 221
 222 void txtwin_free(struct txtwin *tw)
 223 {
 224         char *show = "\x1b[?25h";
 225         fb_free();
 226         destroy_bitmap(bitmap);
 227         g_object_unref(context);
 228         g_object_unref(fontmap);
 229         write(STDIN_FILENO, show, strlen(show));
 230 }