common/draw.c

   1 /*
   2  * draw.c - draw functions
   3  *
   4  * Copyright © 2007-2008 Julien Danjou <julien@danjou.info>
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License as published by
   8  * the Free Software Foundation; either version 2 of the License, or
   9  * (at your option) any later version.
  10  *
  11  * This program is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14  * GNU General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU General Public License along
  17  * with this program; if not, write to the Free Software Foundation, Inc.,
  18  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
  19  *
  20  */
  21
  22 #include <cairo.h>
  23 #include <cairo-ft.h>
  24 #include <cairo-xlib.h>
  25
  26 #include <langinfo.h>
  27 #include <iconv.h>
  28 #include <errno.h>
  29
  30 #include <math.h>
  31
  32 #include "draw.h"
  33 #include "common/util.h"
  34
  35 static char *
  36 draw_iso2utf8(char *iso)
  37 {
  38     iconv_t iso2utf8;
  39     size_t len, utf8len;
  40     char *utf8;
  41
  42     if(!(len = a_strlen(iso)))
  43         return NULL;
  44
  45     if(!a_strcmp(nl_langinfo(CODESET), "UTF-8"))
  46         return iso;
  47
  48     iso2utf8 = iconv_open("UTF-8", nl_langinfo(CODESET));
  49     if(iso2utf8 == (iconv_t) -1)
  50     {
  51         if(errno == EINVAL)
  52             warn("unable to convert text from %s to UTF-8, not available",
  53                  nl_langinfo(CODESET));
  54         else
  55             perror("awesome: unable to convert text");
  56
  57         return NULL;
  58     }
  59
  60     utf8len = (3 * len) / 2 + 1;
  61     utf8 = p_new(char, utf8len);
  62
  63     if(iconv(iso2utf8, &iso, &len, &utf8, &utf8len) == (size_t) -1)
  64     {
  65         perror("awesome: text conversion failed");
  66         return NULL;
  67     }
  68
  69     if(iconv_close(iso2utf8))
  70         warn("error closing iconv");
  71
  72     return utf8;
  73 }
  74
  75 /** Get a draw context
  76  * \param phys_screen physical screen id
  77  * \param width width
  78  * \param height height
  79  * \return draw context ref
  80  */
  81 DrawCtx *
  82 draw_context_new(Display *disp, int phys_screen, int width, int height, Drawable dw)
  83 {
  84     DrawCtx *d = p_new(DrawCtx, 1);
  85
  86     d->display = disp;
  87     d->phys_screen = phys_screen;
  88     d->width = width;
  89     d->height = height;
  90     d->depth = DefaultDepth(disp, phys_screen);
  91     d->visual = DefaultVisual(disp, phys_screen);
  92     d->drawable = dw;
  93     d->surface = cairo_xlib_surface_create(disp, dw, d->visual, width, height);
  94     d->cr = cairo_create(d->surface);
  95
  96     return d;
  97 };
  98
  99 void
 100 draw_context_delete(DrawCtx *ctx)
 101 {
 102     cairo_surface_destroy(ctx->surface);
 103     cairo_destroy(ctx->cr);
 104     p_delete(&ctx);
 105 }
 106
 107 /** Draw text into a draw context
 108  * \param x x coord
 109  * \param y y coord
 110  * \param w width
 111  * \param h height
 112  * \param align alignment
 113  * \param padding padding to add before drawing the text
 114  * \param font font to use
 115  * \param text text to draw
 116  * \param fg foreground color
 117  * \param bg background color
 118  */
 119 void
 120 draw_text(DrawCtx *ctx,
 121           Area area,
 122           Alignment align,
 123           int padding,
 124           XftFont *font, char *text,
 125           XColor fg, XColor bg)
 126 {
 127     int nw = 0;
 128     ssize_t len, olen;
 129     char *buf;
 130     cairo_font_face_t *font_face;
 131
 132     draw_rectangle(ctx, area, True, bg);
 133
 134     if(!(len = olen = a_strlen(text)))
 135         return;
 136
 137     /* copy text to buffer */
 138     buf = a_strdup(text);
 139     /* try to convert it to UTF-8 */
 140     if(!(buf = draw_iso2utf8(buf)))
 141         return;
 142
 143     /* check that the text is not too long */
 144     while(len && (nw = (draw_textwidth(ctx->display, font, buf)) + padding * 2) > area.width)
 145     {
 146         len--;
 147         /* we can't blindly null the char, we need to check if it's not part of
 148          * a multi byte char: if mbtowc return -1, we know that we must go back
 149          * in the string to find the beginning of the multi byte char */
 150         while(mbtowc(NULL, buf + len, a_strlen(buf + len)) < 0)
 151             len--;
 152         buf[len] = '\0';
 153     }
 154     if(nw > area.width)
 155         return;                 /* too long */
 156     if(len < olen)
 157     {
 158         if(len > 1)
 159             buf[len - 1] = '.';
 160         if(len > 2)
 161             buf[len - 2] = '.';
 162         if(len > 3)
 163             buf[len - 3] = '.';
 164     }
 165
 166     font_face = cairo_ft_font_face_create_for_pattern(font->pattern);
 167     cairo_set_font_face(ctx->cr, font_face);
 168     cairo_set_font_size(ctx->cr, font->height);
 169     cairo_set_source_rgb(ctx->cr, fg.red / 65535.0, fg.green / 65535.0, fg.blue / 65535.0);
 170
 171     switch(align)
 172     {
 173       case AlignLeft:
 174         cairo_move_to(ctx->cr, area.x + padding, area.y + font->ascent + (ctx->height - font->height) / 2);
 175         break;
 176       case AlignRight:
 177         cairo_move_to(ctx->cr, area.x + (area.width - nw) + padding,
 178                       area.y + font->ascent + (ctx->height - font->height) / 2);
 179         break;
 180       default:
 181         cairo_move_to(ctx->cr, area.x + ((area.width - nw) / 2) + padding,
 182                       area.y + font->ascent + (ctx->height - font->height) / 2);
 183         break;
 184     }
 185
 186     cairo_show_text(ctx->cr, buf);
 187
 188     cairo_font_face_destroy(font_face);
 189     p_delete(&buf);
 190 }
 191
 192 /** Setup color-source for cairo (gradient or mono)
 193  * \param ctx Draw context
 194  * \param x x-offset of widget
 195  * \param y y-offset of widget
 196  * \param width width in pixels
 197  * \param color color to use from 0%
 198  * \param pcolor_center color at 50% of width
 199  * \param pcolor_end color at 100% of width
 200  * \return pat pattern or NULL; needs to get cairo_pattern_destroy()'ed;
 201  */
 202 cairo_pattern_t *
 203 setup_cairo_color_source(DrawCtx *ctx, int x, int y, int width,
 204                          XColor color, XColor *pcolor_center, XColor *pcolor_end)
 205 {
 206     cairo_pattern_t *pat;
 207
 208     if(pcolor_center || pcolor_end) /* draw a gradient */
 209     {
 210         pat = cairo_pattern_create_linear(x, y, x + width, y);
 211
 212         cairo_pattern_add_color_stop_rgb(pat, 0, color.red / 65535.0,
 213                                          color.green / 65535.0, color.blue / 65535.0);
 214         if(pcolor_center)
 215             cairo_pattern_add_color_stop_rgb(pat, 0.5, pcolor_center->red / 65535.0,
 216                                              pcolor_center->green / 65535.0, pcolor_center->blue / 65535.0);
 217         if(pcolor_end)
 218             cairo_pattern_add_color_stop_rgb(pat, 1, pcolor_end->red / 65535.0,
 219                                              pcolor_end->green / 65535.0, pcolor_end->blue / 65535.0);
 220         else
 221             cairo_pattern_add_color_stop_rgb(pat, 1, color.red / 65535.0,
 222                                              color.green / 65535.0, color.blue / 65535.0);
 223         cairo_set_source(ctx->cr, pat);
 224         return pat;
 225     }
 226     else /* no gradient */
 227     {
 228         cairo_set_source_rgb(ctx->cr, color.red / 65535.0, color.green / 65535.0, color.blue / 65535.0);
 229         return NULL;
 230     }
 231 }
 232
 233 /** Draw rectangle
 234  * \param ctx Draw context
 235  * \param geometry geometry
 236  * \param filled filled rectangle?
 237  * \param color color to use
 238  */
 239 void
 240 draw_rectangle(DrawCtx *ctx, Area geometry, Bool filled, XColor color)
 241 {
 242     cairo_set_antialias(ctx->cr, CAIRO_ANTIALIAS_NONE);
 243     cairo_set_line_width(ctx->cr, 1.0);
 244     cairo_set_source_rgb(ctx->cr, color.red / 65535.0, color.green / 65535.0, color.blue / 65535.0);
 245     if(filled)
 246     {
 247         cairo_rectangle(ctx->cr, geometry.x, geometry.y, geometry.width, geometry.height);
 248         cairo_fill(ctx->cr);
 249     }
 250     else
 251     {
 252         cairo_rectangle(ctx->cr, geometry.x + 1, geometry.y, geometry.width - 1, geometry.height - 1);
 253         cairo_stroke(ctx->cr);
 254     }
 255 }
 256 /** Draw rectangle with gradient colors
 257  * \param ctx Draw context
 258  * \param geometry geometry
 259  * \param fullwidth width of full bar in pixels
 260  * \param filled filled rectangle?
 261  * \param color color to use from 0%
 262  * \param pcolor_center color at 50%
 263  * \param pcolor_end color at 100%
 264  */
 265 void
 266 draw_rectangle_gradient(DrawCtx *ctx, Area geometry, int fullwidth, Bool filled,
 267                         XColor color, XColor *pcolor_center, XColor *pcolor_end)
 268 {
 269     cairo_pattern_t *pat;
 270
 271     cairo_set_antialias(ctx->cr, CAIRO_ANTIALIAS_NONE);
 272     cairo_set_line_width(ctx->cr, 1.0);
 273
 274     pat = setup_cairo_color_source(ctx, geometry.x, geometry.y, fullwidth,
 275                                    color, pcolor_center, pcolor_end);
 276
 277     if(filled)
 278     {
 279         cairo_rectangle(ctx->cr, geometry.x, geometry.y, geometry.width, geometry.height);
 280         cairo_fill(ctx->cr);
 281     }
 282     else
 283     {
 284         cairo_rectangle(ctx->cr, geometry.x + 1, geometry.y, geometry.width - 1, geometry.height - 1);
 285         cairo_stroke(ctx->cr);
 286     }
 287
 288     if(pat)
 289         cairo_pattern_destroy(pat);
 290 }
 291
 292 /** Setup some cairo-things for drawing a graph
 293  * \param ctx Draw context
 294  */
 295 void
 296 draw_graph_setup(DrawCtx *ctx)
 297 {
 298     cairo_set_antialias(ctx->cr, CAIRO_ANTIALIAS_NONE);
 299     cairo_set_line_width(ctx->cr, 1.0);
 300     /* without it, it can draw over the path on sharp angles (...too long lines) */
 301     cairo_set_line_join (ctx->cr, CAIRO_LINE_JOIN_ROUND);
 302 }
 303 /** Draw a graph
 304  * \param ctx Draw context
 305  * \param x x-offset of widget
 306  * \param y y-offset of widget
 307  * \param w width in pixels
 308  * \param from array of starting-point offsets to draw a graph-lines
 309  * \param to array of end-point offsets to draw a graph-lines
 310  * \param cur_index current position in data-array (cycles around)
 311  * \param color color to use from 0%
 312  * \param pcolor_center color at 50%
 313  * \param pcolor_end color at 100%
 314  */
 315 void
 316 draw_graph(DrawCtx *ctx, int x, int y, int w, int *from, int *to, int cur_index,
 317            XColor color, XColor *pcolor_center, XColor *pcolor_end)
 318 {
 319     int i;
 320     cairo_pattern_t *pat;
 321     pat = setup_cairo_color_source(ctx, x, y, w, color, pcolor_center, pcolor_end);
 322
 323     i = -1;
 324     while(++i < w)
 325     {
 326         cairo_move_to(ctx->cr, x, y - from[cur_index]);
 327         cairo_line_to(ctx->cr, x, y - to[cur_index]);
 328         x++;
 329
 330         if (--cur_index < 0)
 331             cur_index = w - 1;
 332     }
 333
 334     cairo_stroke(ctx->cr);
 335
 336     if(pat)
 337         cairo_pattern_destroy(pat);
 338 }
 339 /** Draw a line into a graph-widget
 340  * \param ctx Draw context
 341  * \param x x-offset of widget
 342  * \param y y-offset of widget
 343  * \param w width in pixels
 344  * \param to array of offsets to draw the line through...
 345  * \param cur_index current position in data-array (cycles around)
 346  * \param color color to use from 0%
 347  * \param pcolor_center color at 50%
 348  * \param pcolor_end color at 100%
 349  */
 350 void
 351 draw_graph_line(DrawCtx *ctx, int x, int y, int w, int *to, int cur_index,
 352            XColor color, XColor *pcolor_center, XColor *pcolor_end)
 353 {
 354     int i;
 355     int flag = 0; /* used to prevent drawing a line from 0 to 0 values */
 356     cairo_pattern_t *pat;
 357
 358     pat = setup_cairo_color_source(ctx, x, y, w, color, pcolor_center, pcolor_end);
 359
 360     /* x-1 (on the border), paints *from* the last point (... not included itself) */
 361     /* makes sense when you assume there is already some line drawn to it. */
 362     cairo_move_to(ctx->cr, x - 1, y - to[cur_index]);
 363
 364     for (i = 0; i < w; i++)
 365     {
 366         if (to[cur_index] > 0)
 367         {
 368             cairo_line_to(ctx->cr, x, y - to[cur_index]);
 369             flag = 1;
 370         }
 371         else
 372         {
 373             if(flag) /* only draw from values > 0 to 0-values */
 374             {
 375                 cairo_line_to(ctx->cr, x, y);
 376                 flag = 0;
 377             }
 378             else
 379                 cairo_move_to(ctx->cr, x, y);
 380         }
 381
 382         if (--cur_index < 0) /* cycles around the index */
 383             cur_index = w - 1;
 384         x++;
 385     }
 386     cairo_stroke(ctx->cr);
 387
 388     if(pat)
 389         cairo_pattern_destroy(pat);
 390 }
 391
 392 void
 393 draw_circle(DrawCtx *ctx, int x, int y, int r, Bool filled, XColor color)
 394 {
 395     cairo_set_line_width(ctx->cr, 1.0);
 396     cairo_set_source_rgb(ctx->cr, color.red / 65535.0, color.green / 65535.0, color.blue / 65535.0);
 397
 398     cairo_new_sub_path(ctx->cr); /* don't draw from the old reference point to.. */
 399
 400     if(filled)
 401     {
 402         cairo_arc (ctx->cr, x + r, y + r, r, 0, 2 * M_PI);
 403         cairo_fill(ctx->cr);
 404     }
 405     else
 406         cairo_arc (ctx->cr, x + r, y + r, r - 1, 0, 2 * M_PI);
 407
 408     cairo_stroke(ctx->cr);
 409 }
 410
 411 void draw_image_from_argb_data(DrawCtx *ctx, int x, int y, int w, int h,
 412                                int wanted_h, unsigned char *data)
 413 {
 414     double ratio;
 415     cairo_t *cr;
 416     cairo_surface_t *source;
 417
 418     source = cairo_image_surface_create_for_data(data, CAIRO_FORMAT_ARGB32, w, h, 0);
 419     cr = cairo_create(ctx->surface);
 420     if(wanted_h > 0 && h > 0)
 421     {
 422         ratio = (double) wanted_h / (double) h;
 423         cairo_scale(cr, ratio, ratio);
 424         cairo_set_source_surface(cr, source, x / ratio, y / ratio);
 425     }
 426     else
 427         cairo_set_source_surface(cr, source, x, y);
 428
 429     cairo_paint(cr);
 430
 431     cairo_surface_destroy(source);
 432 }
 433
 434 void
 435 draw_image(DrawCtx *ctx, int x, int y, int wanted_h, const char *filename)
 436 {
 437     double ratio;
 438     int h;
 439     cairo_surface_t *source;
 440     cairo_t *cr;
 441     cairo_status_t cairo_st;
 442
 443     source = cairo_image_surface_create_from_png(filename);
 444     if((cairo_st = cairo_surface_status(source)))
 445     {
 446         warn("failed to draw image %s: %s\n", filename, cairo_status_to_string(cairo_st));
 447         return;
 448     }
 449     cr = cairo_create (ctx->surface);
 450     if(wanted_h > 0 && (h = cairo_image_surface_get_height(source)) > 0)
 451     {
 452         ratio = (double) wanted_h / (double) h;
 453         cairo_scale(cr, ratio, ratio);
 454         cairo_set_source_surface(cr, source, x / ratio, y / ratio);
 455     }
 456     else
 457         cairo_set_source_surface(cr, source, x, y);
 458     cairo_paint(cr);
 459
 460     cairo_destroy(cr);
 461     cairo_surface_destroy(source);
 462 }
 463
 464 Area
 465 draw_get_image_size(const char *filename)
 466 {
 467     Area size = { -1, -1, -1, -1, NULL };
 468     cairo_surface_t *surface;
 469     cairo_status_t cairo_st;
 470
 471     surface = cairo_image_surface_create_from_png(filename);
 472     if((cairo_st = cairo_surface_status(surface)))
 473         warn("failed to get image size %s: %s\n", filename, cairo_status_to_string(cairo_st));
 474     else
 475     {
 476         cairo_image_surface_get_width(surface);
 477         size.x = 0;
 478         size.y = 0;
 479         size.width = cairo_image_surface_get_width(surface);
 480         size.height = cairo_image_surface_get_height(surface);
 481         cairo_surface_destroy(surface);
 482     }
 483
 484     return size;
 485 }
 486
 487 Drawable
 488 draw_rotate(DrawCtx *ctx, int screen, double angle, int tx, int ty)
 489 {
 490     cairo_surface_t *surface, *source;
 491     cairo_t *cr;
 492     Drawable newdrawable;
 493
 494     newdrawable = XCreatePixmap(ctx->display,
 495                                 RootWindow(ctx->display, screen),
 496                                 ctx->height, ctx->width,
 497                                 ctx->depth);
 498     surface = cairo_xlib_surface_create(ctx->display, newdrawable, ctx->visual, ctx->height, ctx->width);
 499     source = cairo_xlib_surface_create(ctx->display, ctx->drawable, ctx->visual, ctx->width, ctx->height);
 500     cr = cairo_create (surface);
 501
 502     cairo_translate(cr, tx, ty);
 503     cairo_rotate(cr, angle);
 504
 505     cairo_set_source_surface(cr, source, 0.0, 0.0);
 506     cairo_paint(cr);
 507
 508     cairo_destroy(cr);
 509     cairo_surface_destroy(source);
 510     cairo_surface_destroy(surface);
 511
 512     return newdrawable;
 513 }
 514
 515 unsigned short
 516 draw_textwidth(Display *disp, XftFont *font, char *text)
 517 {
 518     cairo_surface_t *surface;
 519     cairo_t *cr;
 520     cairo_font_face_t *font_face;
 521     cairo_text_extents_t te;
 522
 523     if (!a_strlen(text))
 524         return 0;
 525
 526     surface = cairo_xlib_surface_create(disp, DefaultScreen(disp),
 527                                         DefaultVisual(disp, DefaultScreen(disp)),
 528                                         DisplayWidth(disp, DefaultScreen(disp)),
 529                                         DisplayHeight(disp, DefaultScreen(disp)));
 530     cr = cairo_create(surface);
 531     font_face = cairo_ft_font_face_create_for_pattern(font->pattern);
 532     cairo_set_font_face(cr, font_face);
 533     cairo_set_font_size(cr, font->height);
 534     cairo_text_extents(cr, text, &te);
 535     cairo_destroy(cr);
 536     cairo_surface_destroy(surface);
 537     cairo_font_face_destroy(font_face);
 538
 539     return MAX(te.x_advance, te.width);
 540 }
 541
 542 Alignment
 543 draw_get_align(const char *align)
 544 {
 545     if(!a_strncmp(align, "left", 4))
 546         return AlignLeft;
 547     else if(!a_strncmp(align, "center", 6))
 548         return AlignCenter;
 549     else if(!a_strncmp(align, "right", 5))
 550         return AlignRight;
 551
 552     return AlignAuto;
 553 }
 554
 555 /** Initialize an X color
 556  * \param disp display ref
 557  * \param screen Physical screen number
 558  * \param colstr Color specification
 559  * \return XColor struct
 560  */
 561 XColor
 562 draw_color_new(Display *disp, int phys_screen, const char *colstr)
 563 {
 564     XColor screenColor, exactColor;
 565
 566     if(!XAllocNamedColor(disp,
 567                          DefaultColormap(disp, phys_screen),
 568                          colstr,
 569                          &screenColor,
 570                          &exactColor))
 571         eprint("awesome: error, cannot allocate color '%s'\n", colstr);
 572
 573     return screenColor;
 574 }
 575
 576 /** Remove a area from a list of them,
 577  * spliting the space between several area that
 578  * can overlaps
 579  * \param head list head
 580  * \param elem area to remove
 581  */
 582 void
 583 area_list_remove(Area **head, Area *elem)
 584 {
 585     Area *r, inter, *extra;
 586
 587     area_list_detach(head, elem);
 588
 589     for(r = *head; r; r = r->next)
 590         if(area_intersect_area(*r, *elem))
 591         {
 592             /* remove it from the list */
 593             area_list_detach(head, r);
 594
 595             inter = area_get_intersect_area(*r, *elem);
 596
 597             if(AREA_LEFT(inter) > AREA_LEFT(*r))
 598             {
 599                 extra = p_new(Area, 1);
 600                 extra->x = r->x;
 601                 extra->y = r->y;
 602                 extra->width = AREA_LEFT(inter) - r->x;
 603                 extra->height = r->height;
 604                 area_list_push(head, extra);
 605             }
 606
 607             if(AREA_TOP(inter) > AREA_TOP(*r))
 608             {
 609                 extra = p_new(Area, 1);
 610                 extra->x = r->x;
 611                 extra->y = r->y;
 612                 extra->width = r->width;
 613                 extra->height = AREA_TOP(inter) - r->y;
 614                 area_list_push(head, extra);
 615             }
 616
 617             if(AREA_RIGHT(inter) < AREA_RIGHT(*r))
 618             {
 619                 extra = p_new(Area, 1);
 620                 extra->x = AREA_RIGHT(inter);
 621                 extra->y = r->y;
 622                 extra->width = AREA_RIGHT(*r) - AREA_RIGHT(inter);
 623                 extra->height = r->height;
 624                 area_list_push(head, extra);
 625             }
 626
 627             if(AREA_BOTTOM(inter) < AREA_BOTTOM(*r))
 628             {
 629                 extra = p_new(Area, 1);
 630                 extra->x = r->x;
 631                 extra->y = AREA_BOTTOM(inter);
 632                 extra->width = r->width;
 633                 extra->height = AREA_BOTTOM(*r) - AREA_BOTTOM(inter);
 634                 area_list_push(head, extra);
 635             }
 636         }
 637 }
 638
 639 // vim: filetype=c:expandtab:shiftwidth=4:tabstop=8:softtabstop=4:encoding=utf-8:textwidth=80