text.cpp

   1 #include <msp/gl/matrix.h>
   2 #include <msp/gl/meshbuilder.h>
   3 #include <msp/gl/texture2d.h>
   4 #include "partcache.h"
   5 #include "style.h"
   6 #include "text.h"
   7
   8 using namespace std;
   9
  10 namespace Msp {
  11 namespace GLtk {
  12
  13 struct Text::RenderData
  14 {
  15         GL::PrimitiveBuilder *bld;
  16 };
  17
  18 struct Text::CoordsToGeomData
  19 {
  20         unsigned row;
  21         unsigned col;
  22         Geometry result;
  23 };
  24
  25
  26 Text::Text():
  27         style(0)
  28 { }
  29
  30 Text::Text(const Style &s, const string &t):
  31         style(&s)
  32 {
  33         set(t);
  34 }
  35
  36 void Text::set_style(const Style *s)
  37 {
  38         style = s;
  39
  40         if(style)
  41         {
  42                 const GL::Font &font = style->get_font();
  43                 float font_size = style->get_font_size();
  44                 for(vector<Line>::iterator i=lines.begin(); i!=lines.end(); ++i)
  45                         i->width = static_cast<unsigned>(font.get_string_width(text.substr(i->start, i->length))*font_size);
  46         }
  47 }
  48
  49 unsigned Text::get_width() const
  50 {
  51         unsigned width = 0;
  52         for(vector<Line>::const_iterator i=lines.begin(); i!=lines.end(); ++i)
  53                 width = max(width, i->width);
  54         return width;
  55 }
  56
  57 unsigned Text::get_height() const
  58 {
  59         if(!style)
  60                 return lines.size();
  61
  62         const GL::Font &font = style->get_font();
  63         float font_size = style->get_font_size();
  64         unsigned line_height = static_cast<unsigned>((font.get_ascent()-font.get_descent())*font_size);
  65         unsigned line_spacing = line_height*6/5;
  66         return line_height+(lines.size()-1)*line_spacing;
  67 }
  68
  69 void Text::set(const string &t)
  70 {
  71         text = t;
  72         find_lines();
  73 }
  74
  75 void Text::erase(unsigned pos, unsigned len)
  76 {
  77         text.erase(pos, len);
  78
  79         vector<Line>::iterator i;
  80         for(i=lines.begin(); (i!=lines.end() && i->start+i->length<pos); ++i) ;
  81
  82         if(pos+len>i->start+i->length)
  83                 find_lines();
  84         else
  85         {
  86                 i->length -= len;
  87
  88                 for(++i; i!=lines.end(); ++i)
  89                         i->start -= len;
  90         }
  91 }
  92
  93 void Text::insert(unsigned pos, const string &s)
  94 {
  95         text.insert(pos, s);
  96
  97         if(s.find('\n')!=string::npos)
  98                 find_lines();
  99         else
 100         {
 101                 vector<Line>::iterator i;
 102                 for(i=lines.begin(); (i!=lines.end() && i->start+i->length<pos); ++i) ;
 103
 104                 i->length += s.size();
 105
 106                 for(++i; i!=lines.end(); ++i)
 107                         i->start += s.size();
 108         }
 109 }
 110
 111 unsigned Text::get_line_length(unsigned i) const
 112 {
 113         if(i>=lines.size())
 114                 throw out_of_range("Text::get_line_length");
 115         return lines[i].length;
 116 }
 117
 118 void Text::offset_to_coords(unsigned offs, unsigned &row, unsigned &col) const
 119 {
 120         if(lines.empty())
 121         {
 122                 row = 0;
 123                 col = 0;
 124                 return;
 125         }
 126
 127         for(unsigned i=0; i<lines.size(); ++i)
 128                 if(offs>=lines[i].start && offs<=lines[i].start+lines[i].length)
 129                 {
 130                         row = i;
 131                         col = offs-lines[i].start;
 132                         return;
 133                 }
 134 }
 135
 136 unsigned Text::coords_to_offset(unsigned row, unsigned col) const
 137 {
 138         if(row>=lines.size())
 139                 return text.size();
 140
 141         return lines[row].start+min(col, lines[row].length);
 142 }
 143
 144 Geometry Text::coords_to_geometry(const Part &part, const Geometry &parent, unsigned first_row, unsigned row, unsigned col) const
 145 {
 146         if(row>=lines.size())
 147                 row = lines.size()-1;
 148         const Line &line = lines[row];
 149         if(col>line.length)
 150                 col = line.length;
 151
 152         CoordsToGeomData data;
 153         data.row = row;
 154         data.col = col;
 155
 156         process_lines<CoordsToGeomData, &Text::coords_to_geom_line>(part, parent, first_row, data);
 157
 158         return data.result;
 159 }
 160
 161 void Text::build(const Part &part, const Geometry &parent, CachedPart &cache) const
 162 {
 163         build(part, parent, 0, cache);
 164 }
 165
 166 void Text::build(const Part &part, const Geometry &parent, unsigned first_row, CachedPart &cache) const
 167 {
 168         if(!style || lines.empty())
 169         {
 170                 cache.texture = 0;
 171                 return;
 172         }
 173
 174         cache.clear_mesh();
 175         GL::MeshBuilder bld(*cache.mesh);
 176
 177         const GL::Font &font = style->get_font();
 178         bld.color(style->get_font_color());
 179
 180         RenderData data;
 181         data.bld = &bld;
 182
 183         cache.texture = &font.get_texture();
 184
 185         process_lines<RenderData, &Text::build_line>(part, parent, first_row, data);
 186 }
 187
 188 Text &Text::operator=(const string &t)
 189 {
 190         set(t);
 191         return *this;
 192 }
 193
 194 void Text::find_lines()
 195 {
 196         lines.clear();
 197         float font_size = (style ? style->get_font_size() : 1);
 198         string::size_type start = 0;
 199         while(1)
 200         {
 201                 string::size_type newline = text.find('\n', start);
 202
 203                 Line line;
 204                 line.start = start;
 205                 line.length = (newline==string::npos ? text.size() : newline)-start;
 206                 line.width = line.length;
 207                 if(style)
 208                 {
 209                         string str = text.substr(line.start, line.length);
 210                         line.width = static_cast<unsigned>(style->get_font().get_string_width(str)*font_size);
 211                 }
 212                 lines.push_back(line);
 213
 214                 if(newline==string::npos)
 215                         break;
 216                 start = newline+1;
 217         }
 218 }
 219
 220 template<typename T, void (Text::*func)(unsigned, const Geometry &, T &) const>
 221 void Text::process_lines(const Part &part, const Geometry &parent, unsigned first_row, T &data) const
 222 {
 223         if(!style)
 224                 return;
 225
 226         const GL::Font &font = style->get_font();
 227         float font_size = style->get_font_size();
 228         unsigned line_height = static_cast<unsigned>((font.get_ascent()-font.get_descent())*font_size);
 229         unsigned line_spacing = static_cast<unsigned>(font_size*6/5);
 230         unsigned height = line_height+(lines.size()-1)*line_spacing;
 231         int y_offset = static_cast<int>(-font.get_descent()*font_size);
 232
 233         const Sides &margin = part.get_margin();
 234         unsigned n_lines = min(lines.size(), max((parent.h-margin.top-margin.bottom)/line_spacing, 1U));
 235         first_row = min(first_row, lines.size()-n_lines);
 236
 237         for(unsigned i=0; i<n_lines; ++i)
 238         {
 239                 const Line &line = lines[first_row+i];
 240
 241                 Geometry rgeom;
 242                 rgeom.w = line.width;
 243                 rgeom.h = height;
 244                 rgeom.y = (n_lines-1-i)*line_spacing+y_offset;
 245                 part.get_alignment().apply(rgeom, parent, part.get_margin());
 246
 247                 (this->*func)(first_row+i, rgeom, data);
 248         }
 249 }
 250
 251 void Text::build_line(unsigned i, const Geometry &rgeom, RenderData &data) const
 252 {
 253         const Line &line = lines[i];
 254
 255         GL::MatrixStack::Push _pushm(data.bld->matrix());
 256         data.bld->matrix() *= GL::Matrix::translation(rgeom.x, rgeom.y, 0);
 257         data.bld->matrix() *= GL::Matrix::scaling(style->get_font_size());
 258
 259         style->get_font().build_string(text.substr(line.start, line.length), *data.bld);
 260 }
 261
 262 void Text::coords_to_geom_line(unsigned i, const Geometry &rgeom, CoordsToGeomData &data) const
 263 {
 264         if(i==data.row)
 265         {
 266                 float w = style->get_font().get_string_width(text.substr(lines[i].start, data.col));
 267                 data.result = rgeom;
 268                 data.result.x += static_cast<unsigned>(w*style->get_font_size());
 269         }
 270 }
 271
 272 } // namespace GLtk
 273 } // namespace Msp