src/fl_line_style.cxx

   1 //
   2 // "$Id: fl_line_style.cxx 8190 2011-01-05 10:21:45Z manolo $"
   3 //
   4 // Line style code for the Fast Light Tool Kit (FLTK).
   5 //
   6 // Copyright 1998-2010 by Bill Spitzak and others.
   7 //
   8 // This library is free software; you can redistribute it and/or
   9 // modify it under the terms of the GNU Library General Public
  10 // License as published by the Free Software Foundation; either
  11 // version 2 of the License, or (at your option) any later version.
  12 //
  13 // This library is distributed in the hope that it will be useful,
  14 // but WITHOUT ANY WARRANTY; without even the implied warranty of
  15 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  16 // Library General Public License for more details.
  17 //
  18 // You should have received a copy of the GNU Library General Public
  19 // License along with this library; if not, write to the Free Software
  20 // Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
  21 // USA.
  22 //
  23 // Please report all bugs and problems on the following page:
  24 //
  25 //     http://www.fltk.org/str.php
  26 //
  27
  28 /**
  29   \file fl_line_style.cxx
  30   \brief Line style drawing utility hiding different platforms.
  31 */
  32
  33 #include <FL/Fl.H>
  34 #include <FL/fl_draw.H>
  35 #include <FL/x.H>
  36 #include <FL/Fl_Printer.H>
  37 #include "flstring.h"
  38 #include <stdio.h>
  39
  40 // We save the current line width (absolute value) here.
  41 // This is currently used only for X11 clipping, see src/fl_rect.cxx.
  42 // FIXME: this would probably better be in class Fl::
  43 int fl_line_width_ = 0;
  44
  45 #ifdef __APPLE_QUARTZ__
  46 float fl_quartz_line_width_ = 1.0f;
  47 static enum CGLineCap fl_quartz_line_cap_ = kCGLineCapButt;
  48 static enum CGLineJoin fl_quartz_line_join_ = kCGLineJoinMiter;
  49 static CGFloat *fl_quartz_line_pattern = 0;
  50 static int fl_quartz_line_pattern_size = 0;
  51 void fl_quartz_restore_line_style_() {
  52   CGContextSetLineWidth(fl_gc, fl_quartz_line_width_);
  53   CGContextSetLineCap(fl_gc, fl_quartz_line_cap_);
  54   CGContextSetLineJoin(fl_gc, fl_quartz_line_join_);
  55   CGContextSetLineDash(fl_gc, 0, fl_quartz_line_pattern, fl_quartz_line_pattern_size);
  56 }
  57 #endif
  58
  59 void Fl_Graphics_Driver::line_style(int style, int width, char* dashes) {
  60
  61   // save line width in global variable for X11 clipping
  62   if (width == 0) fl_line_width_ = 1;
  63   else fl_line_width_ = width>0 ? width : -width;
  64
  65 #if defined(USE_X11)
  66   int ndashes = dashes ? strlen(dashes) : 0;
  67   // emulate the WIN32 dash patterns on X
  68   char buf[7];
  69   if (!ndashes && (style&0xff)) {
  70     int w = width ? width : 1;
  71     char dash, dot, gap;
  72     // adjust lengths to account for cap:
  73     if (style & 0x200) {
  74       dash = char(2*w);
  75       dot = 1; // unfortunately 0 does not work
  76       gap = char(2*w-1);
  77     } else {
  78       dash = char(3*w);
  79       dot = gap = char(w);
  80     }
  81     char* p = dashes = buf;
  82     switch (style & 0xff) {
  83     case FL_DASH:       *p++ = dash; *p++ = gap; break;
  84     case FL_DOT:        *p++ = dot; *p++ = gap; break;
  85     case FL_DASHDOT:    *p++ = dash; *p++ = gap; *p++ = dot; *p++ = gap; break;
  86     case FL_DASHDOTDOT: *p++ = dash; *p++ = gap; *p++ = dot; *p++ = gap; *p++ = dot; *p++ = gap; break;
  87     }
  88     ndashes = p-buf;
  89   }
  90   static int Cap[4] = {CapButt, CapButt, CapRound, CapProjecting};
  91   static int Join[4] = {JoinMiter, JoinMiter, JoinRound, JoinBevel};
  92   XSetLineAttributes(fl_display, fl_gc, width,
  93                      ndashes ? LineOnOffDash : LineSolid,
  94                      Cap[(style>>8)&3], Join[(style>>12)&3]);
  95   if (ndashes) XSetDashes(fl_display, fl_gc, 0, dashes, ndashes);
  96 #elif defined(WIN32)
  97   // According to Bill, the "default" cap and join should be the
  98   // "fastest" mode supported for the platform.  I don't know why
  99   // they should be different (same graphics cards, etc., right?) MRS
 100   static DWORD Cap[4]= {PS_ENDCAP_FLAT, PS_ENDCAP_FLAT, PS_ENDCAP_ROUND, PS_ENDCAP_SQUARE};
 101   static DWORD Join[4]={PS_JOIN_ROUND, PS_JOIN_MITER, PS_JOIN_ROUND, PS_JOIN_BEVEL};
 102   int s1 = PS_GEOMETRIC | Cap[(style>>8)&3] | Join[(style>>12)&3];
 103   DWORD a[16]; int n = 0;
 104   if (dashes && dashes[0]) {
 105     s1 |= PS_USERSTYLE;
 106     for (n = 0; n < 16 && *dashes; n++) a[n] = *dashes++;
 107   } else {
 108     s1 |= style & 0xff; // allow them to pass any low 8 bits for style
 109   }
 110   if ((style || n) && !width) width = 1; // fix cards that do nothing for 0?
 111   LOGBRUSH penbrush = {BS_SOLID,fl_RGB(),0}; // can this be fl_brush()?
 112   HPEN newpen = ExtCreatePen(s1, width, &penbrush, n, n ? a : 0);
 113   if (!newpen) {
 114     Fl::error("fl_line_style(): Could not create GDI pen object.");
 115     return;
 116   }
 117   HPEN oldpen = (HPEN)SelectObject(fl_gc, newpen);
 118   DeleteObject(oldpen);
 119   DeleteObject(fl_current_xmap->pen);
 120   fl_current_xmap->pen = newpen;
 121 #elif defined(__APPLE_QUARTZ__)
 122   static enum CGLineCap Cap[4] = { kCGLineCapButt, kCGLineCapButt,
 123                                    kCGLineCapRound, kCGLineCapSquare };
 124   static enum CGLineJoin Join[4] = { kCGLineJoinMiter, kCGLineJoinMiter,
 125                                     kCGLineJoinRound, kCGLineJoinBevel };
 126   if (width<1) width = 1;
 127   fl_quartz_line_width_ = (float)width;
 128   fl_quartz_line_cap_ = Cap[(style>>8)&3];
 129   // when printing kCGLineCapSquare seems better for solid lines
 130   if ( Fl_Surface_Device::surface()->class_name() == Fl_Printer::class_id && style == FL_SOLID && dashes == NULL ) {
 131     fl_quartz_line_cap_ = kCGLineCapSquare;
 132     }
 133   fl_quartz_line_join_ = Join[(style>>12)&3];
 134   char *d = dashes;
 135   static CGFloat pattern[16];
 136   if (d && *d) {
 137         CGFloat *p = pattern;
 138     while (*d) { *p++ = (float)*d++; }
 139     fl_quartz_line_pattern = pattern;
 140     fl_quartz_line_pattern_size = d-dashes;
 141   } else if (style & 0xff) {
 142     char dash, dot, gap;
 143     // adjust lengths to account for cap:
 144     if (style & 0x200) {
 145       dash = char(2*width);
 146       dot = 1;
 147       gap = char(2*width-1);
 148     } else {
 149       dash = char(3*width);
 150       dot = gap = char(width);
 151     }
 152         CGFloat *p = pattern;
 153     switch (style & 0xff) {
 154     case FL_DASH:       *p++ = dash; *p++ = gap; break;
 155     case FL_DOT:        *p++ = dot; *p++ = gap; break;
 156     case FL_DASHDOT:    *p++ = dash; *p++ = gap; *p++ = dot; *p++ = gap; break;
 157     case FL_DASHDOTDOT: *p++ = dash; *p++ = gap; *p++ = dot; *p++ = gap; *p++ = dot; *p++ = gap; break;
 158     }
 159     fl_quartz_line_pattern_size = p-pattern;
 160     fl_quartz_line_pattern = pattern;
 161   } else {
 162     fl_quartz_line_pattern = 0;
 163                 fl_quartz_line_pattern_size = 0;
 164   }
 165   fl_quartz_restore_line_style_();
 166 #else
 167 # error unsupported platform
 168 #endif
 169 }
 170
 171
 172 //
 173 // End of "$Id: fl_line_style.cxx 8190 2011-01-05 10:21:45Z manolo $".
 174 //