draw.c

   1 /* See LICENSE file for copyright and license details. */
   2
   3 /* enums */
   4 enum { ColFG, ColBG, ColLast };
   5
   6 /* typedefs */
   7 typedef struct {
   8         int x, y, w, h;
   9         unsigned long norm[ColLast];
  10         unsigned long sel[ColLast];
  11         Drawable drawable;
  12         GC gc;
  13         struct {
  14                 XFontStruct *xfont;
  15                 XFontSet set;
  16                 int ascent;
  17                 int descent;
  18                 int height;
  19         } font;
  20 } DC; /* draw context */
  21
  22 /* forward declarations */
  23 static void dccleanup(void);
  24 static void dcsetup(void);
  25 static void drawtext(const char *text, unsigned long col[ColLast]);
  26 static unsigned long getcolor(const char *colstr);
  27 static void initfont(const char *fontstr);
  28 static int textnw(const char *text, unsigned int len);
  29 static int textw(const char *text);
  30
  31 static DC dc;
  32
  33 void
  34 dccleanup(void) {
  35         if(dc.font.set)
  36                 XFreeFontSet(dpy, dc.font.set);
  37         else
  38                 XFreeFont(dpy, dc.font.xfont);
  39         XFreePixmap(dpy, dc.drawable);
  40         XFreeGC(dpy, dc.gc);
  41 }
  42
  43 void
  44 dcsetup(void) {
  45         /* style */
  46         dc.norm[ColBG] = getcolor(normbgcolor);
  47         dc.norm[ColFG] = getcolor(normfgcolor);
  48         dc.sel[ColBG] = getcolor(selbgcolor);
  49         dc.sel[ColFG] = getcolor(selfgcolor);
  50         initfont(font);
  51
  52         /* pixmap */
  53         dc.drawable = XCreatePixmap(dpy, parent, mw, mh, DefaultDepth(dpy, screen));
  54         dc.gc = XCreateGC(dpy, parent, 0, NULL);
  55         XSetLineAttributes(dpy, dc.gc, 1, LineSolid, CapButt, JoinMiter);
  56         if(!dc.font.set)
  57                 XSetFont(dpy, dc.gc, dc.font.xfont->fid);
  58 }
  59
  60 void
  61 drawtext(const char *text, unsigned long col[ColLast]) {
  62         char buf[256];
  63         int i, x, y, h, len, olen;
  64         XRectangle r = { dc.x, dc.y, dc.w, dc.h };
  65
  66         XSetForeground(dpy, dc.gc, col[ColBG]);
  67         XFillRectangles(dpy, dc.drawable, dc.gc, &r, 1);
  68         if(!text)
  69                 return;
  70         olen = strlen(text);
  71         h = dc.font.height;
  72         y = dc.y + ((h+2) / 2) - (h / 2) + dc.font.ascent;
  73         x = dc.x + (h / 2);
  74         /* shorten text if necessary */
  75         for(len = MIN(olen, sizeof buf); len && textnw(text, len) > dc.w - h; len--);
  76         if(!len)
  77                 return;
  78         memcpy(buf, text, len);
  79         if(len < olen)
  80                 for(i = len; i && i > len - 3; buf[--i] = '.');
  81         XSetForeground(dpy, dc.gc, col[ColFG]);
  82         if(dc.font.set)
  83                 XmbDrawString(dpy, dc.drawable, dc.font.set, dc.gc, x, y, buf, len);
  84         else
  85                 XDrawString(dpy, dc.drawable, dc.gc, x, y, buf, len);
  86 }
  87
  88 unsigned long
  89 getcolor(const char *colstr) {
  90         Colormap cmap = DefaultColormap(dpy, screen);
  91         XColor color;
  92
  93         if(!XAllocNamedColor(dpy, cmap, colstr, &color, &color))
  94                 eprint("drawtext: cannot allocate color '%s'\n", colstr);
  95         return color.pixel;
  96 }
  97
  98 void
  99 initfont(const char *fontstr) {
 100         char *def, **missing = NULL;
 101         int i, n;
 102
 103         if(!fontstr || fontstr[0] == '\0')
 104                 eprint("drawtext: cannot load font: '%s'\n", fontstr);
 105         dc.font.set = XCreateFontSet(dpy, fontstr, &missing, &n, &def);
 106         if(missing)
 107                 XFreeStringList(missing);
 108         if(dc.font.set) {
 109                 XFontStruct **xfonts;
 110                 char **font_names;
 111                 dc.font.ascent = dc.font.descent = 0;
 112                 n = XFontsOfFontSet(dc.font.set, &xfonts, &font_names);
 113                 for(i = 0; i < n; i++) {
 114                         dc.font.ascent = MAX(dc.font.ascent, (*xfonts)->ascent);
 115                         dc.font.descent = MAX(dc.font.descent, (*xfonts)->descent);
 116                         xfonts++;
 117                 }
 118         }
 119         else {
 120                 if(!(dc.font.xfont = XLoadQueryFont(dpy, fontstr))
 121                 && !(dc.font.xfont = XLoadQueryFont(dpy, "fixed")))
 122                         eprint("drawtext: cannot load font: '%s'\n", fontstr);
 123                 dc.font.ascent = dc.font.xfont->ascent;
 124                 dc.font.descent = dc.font.xfont->descent;
 125         }
 126         dc.font.height = dc.font.ascent + dc.font.descent;
 127 }
 128
 129 int
 130 textnw(const char *text, unsigned int len) {
 131         XRectangle r;
 132
 133         if(dc.font.set) {
 134                 XmbTextExtents(dc.font.set, text, len, NULL, &r);
 135                 return r.width;
 136         }
 137         return XTextWidth(dc.font.xfont, text, len);
 138 }
 139
 140 int
 141 textw(const char *text) {
 142         return textnw(text, strlen(text)) + dc.font.height;
 143 }