lily/stencil.cc

   1 /*
   2   stencil.cc -- implement Stencil
   3
   4   source file of the GNU LilyPond music typesetter
   5
   6   (c) 1997--2006 Han-Wen Nienhuys <hanwen@xs4all.nl>
   7 */
   8
   9 #include "stencil.hh"
  10
  11
  12 #include "dimensions.hh"
  13 #include "font-metric.hh"
  14 #include "input-smob.hh"
  15 #include "string-convert.hh"
  16 #include "warn.hh"
  17
  18 #include "ly-smobs.icc"
  19
  20 Stencil::Stencil ()
  21 {
  22   expr_ = SCM_EOL;
  23   set_empty (true);
  24 }
  25
  26 Stencil::Stencil (Box b, SCM func)
  27 {
  28   expr_ = func;
  29   dim_ = b;
  30 }
  31
  32 int
  33 Stencil::print_smob (SCM, SCM port, scm_print_state *)
  34 {
  35   scm_puts ("#<Stencil ", port);
  36   scm_puts (" >", port);
  37   return 1;
  38 }
  39
  40 SCM
  41 Stencil::mark_smob (SCM smob)
  42 {
  43   Stencil *s = (Stencil *) SCM_CELL_WORD_1 (smob);
  44   return s->expr_;
  45 }
  46
  47 IMPLEMENT_SIMPLE_SMOBS (Stencil);
  48 IMPLEMENT_TYPE_P (Stencil, "ly:stencil?");
  49 IMPLEMENT_DEFAULT_EQUAL_P (Stencil);
  50
  51 Interval
  52 Stencil::extent (Axis a) const
  53 {
  54   return dim_[a];
  55 }
  56
  57 bool
  58 Stencil::is_empty () const
  59 {
  60   return (expr_ == SCM_EOL
  61           || dim_[X_AXIS].is_empty ()
  62           || dim_[Y_AXIS].is_empty ());
  63 }
  64
  65 SCM
  66 Stencil::expr () const
  67 {
  68   return expr_;
  69 }
  70
  71 Box
  72 Stencil::extent_box () const
  73 {
  74   return dim_;
  75 }
  76 Offset
  77 Stencil::origin () const
  78 {
  79   return origin_;
  80 }
  81
  82 void
  83 Stencil::translate (Offset o)
  84 {
  85   Axis a = X_AXIS;
  86   while (a < NO_AXES)
  87     {
  88       if (isinf (o[a])
  89           || isnan (o[a])
  90
  91           // ugh, hardcoded.
  92           || fabs (o[a]) > 1e6)
  93         {
  94           programming_error (String_convert::form_string ("Improbable offset for stencil: %f staff space", o[a])
  95                              + "\n"
  96                              + "Setting to zero.");
  97           o[a] = 0.0;
  98         }
  99       incr (a);
 100     }
 101
 102   expr_ = scm_list_n (ly_symbol2scm ("translate-stencil"),
 103                       ly_offset2scm (o),
 104                       expr_, SCM_UNDEFINED);
 105   if (!is_empty ())
 106     dim_.translate (o);
 107   origin_ += o;
 108 }
 109
 110 void
 111 Stencil::translate_axis (Real x, Axis a)
 112 {
 113   Offset o (0, 0);
 114   o[a] = x;
 115   translate (o);
 116 }
 117
 118 void
 119 Stencil::add_stencil (Stencil const &s)
 120 {
 121   expr_ = scm_list_3 (ly_symbol2scm ("combine-stencil"), s.expr_, expr_);
 122   dim_.unite (s.dim_);
 123 }
 124
 125 void
 126 Stencil::set_empty (bool e)
 127 {
 128   if (e)
 129     {
 130       dim_[X_AXIS].set_empty ();
 131       dim_[Y_AXIS].set_empty ();
 132     }
 133   else
 134     {
 135       dim_[X_AXIS] = Interval (0, 0);
 136       dim_[Y_AXIS] = Interval (0, 0);
 137     }
 138 }
 139
 140 void
 141 Stencil::align_to (Axis a, Real x)
 142 {
 143   if (is_empty ())
 144     return;
 145
 146   Interval i (extent (a));
 147   translate_axis (-i.linear_combination (x), a);
 148 }
 149
 150 /* FIXME: unintuitive naming, you would expect *this to be moved.
 151    Kept (keeping?) API for compat with add_at_edge ().
 152
 153    What is PADDING, what is MINIMUM, exactly?  */
 154 Stencil
 155 Stencil::moved_to_edge (Axis a, Direction d, Stencil const &s,
 156                         Real padding, Real minimum) const
 157 {
 158   Interval my_extent = dim_[a];
 159   Interval i (s.extent (a));
 160   Real his_extent;
 161   if (i.is_empty ())
 162     {
 163       programming_error ("Stencil::moved_to_edge: adding empty stencil.");
 164       his_extent = 0.0;
 165       //      SCM_ASSERT_TYPE (0, s.expr (), SCM_ARG1, __FUNCTION__, "non-empty stencil");
 166     }
 167   else
 168     his_extent = i[-d];
 169
 170   Real offset = (my_extent.is_empty () ? 0.0 : my_extent[d] - his_extent)
 171     + d * padding;
 172
 173   Stencil toadd (s);
 174   toadd.translate_axis (offset, a);
 175
 176   if (minimum > 0 && d * (-origin ()[a] + toadd.origin ()[a]) < minimum)
 177     toadd.translate_axis (-toadd.origin ()[a]
 178                           + origin ()[a] + d * minimum, a);
 179
 180   return toadd;
 181 }
 182
 183 /*  See scheme Function.  */
 184 void
 185 Stencil::add_at_edge (Axis a, Direction d, Stencil const &s, Real padding,
 186                       Real minimum)
 187 {
 188   add_stencil (moved_to_edge (a, d, s, padding, minimum));
 189 }
 190
 191 Stencil
 192 Stencil::in_color (Real r, Real g, Real b) const
 193 {
 194   Stencil new_stencil (extent_box (),
 195                        scm_list_3 (ly_symbol2scm ("color"),
 196                                    scm_list_3 (scm_from_double (r),
 197                                                scm_from_double (g),
 198                                                scm_from_double (b)),
 199                                    expr ()));
 200   return new_stencil;
 201 }