source/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::autosize(const Part &part, Geometry &geom) const
  70 {
  71         const Sides &margin = part.get_margin();
  72         geom.w = max(geom.w, get_width()+margin.left+margin.right);
  73         geom.h = max(geom.h, get_height()+margin.top+margin.bottom);
  74 }
  75
  76 void Text::set(const string &t)
  77 {
  78         text = t;
  79         find_lines();
  80 }
  81
  82 void Text::erase(unsigned pos, unsigned len)
  83 {
  84         text.erase(pos, len);
  85
  86         vector<Line>::iterator i;
  87         for(i=lines.begin(); (i!=lines.end() && i->start+i->length<pos); ++i) ;
  88
  89         if(pos+len>i->start+i->length)
  90                 find_lines();
  91         else
  92         {
  93                 i->length -= len;
  94
  95                 for(++i; i!=lines.end(); ++i)
  96                         i->start -= len;
  97         }
  98 }
  99
 100 void Text::insert(unsigned pos, const string &s)
 101 {
 102         text.insert(pos, s);
 103
 104         if(s.find('\n')!=string::npos)
 105                 find_lines();
 106         else
 107         {
 108                 vector<Line>::iterator i;
 109                 for(i=lines.begin(); (i!=lines.end() && i->start+i->length<pos); ++i) ;
 110
 111                 i->length += s.size();
 112
 113                 for(++i; i!=lines.end(); ++i)
 114                         i->start += s.size();
 115         }
 116 }
 117
 118 unsigned Text::get_visible_lines(const Part &part, const Geometry &parent, unsigned *fit_height) const
 119 {
 120         const GL::Font &font = style->get_font();
 121         float font_size = style->get_font_size();
 122         unsigned line_height = static_cast<unsigned>((font.get_ascent()-font.get_descent())*font_size);
 123         unsigned line_spacing = static_cast<unsigned>(font_size*6/5);
 124
 125         const Sides &margin = part.get_margin();
 126         unsigned vmargin = margin.top+margin.bottom;
 127         unsigned free_height = max(parent.h, vmargin)-vmargin+line_spacing-line_height;
 128         unsigned n_lines = min<unsigned>(lines.size(), max(free_height/line_spacing, 1U));
 129         if(fit_height)
 130                 *fit_height = line_height+(n_lines-1)*line_spacing;
 131
 132         return n_lines;
 133 }
 134
 135 unsigned Text::get_line_length(unsigned i) const
 136 {
 137         if(i>=lines.size())
 138                 throw out_of_range("Text::get_line_length");
 139         return lines[i].length;
 140 }
 141
 142 void Text::offset_to_coords(unsigned offs, unsigned &row, unsigned &col) const
 143 {
 144         if(lines.empty())
 145         {
 146                 row = 0;
 147                 col = 0;
 148                 return;
 149         }
 150
 151         for(unsigned i=0; i<lines.size(); ++i)
 152                 if(offs>=lines[i].start && offs<=lines[i].start+lines[i].length)
 153                 {
 154                         row = i;
 155                         col = offs-lines[i].start;
 156                         return;
 157                 }
 158 }
 159
 160 unsigned Text::coords_to_offset(unsigned row, unsigned col) const
 161 {
 162         if(row>=lines.size())
 163                 return text.size();
 164
 165         return lines[row].start+min(col, lines[row].length);
 166 }
 167
 168 Geometry Text::coords_to_geometry(const Part &part, const Geometry &parent, unsigned first_row, unsigned row, unsigned col) const
 169 {
 170         if(row>=lines.size())
 171                 row = lines.size()-1;
 172         const Line &line = lines[row];
 173         if(col>line.length)
 174                 col = line.length;
 175
 176         CoordsToGeomData data;
 177         data.row = row;
 178         data.col = col;
 179
 180         process_lines(part, parent, first_row, &Text::coords_to_geom_line, data);
 181
 182         return data.result;
 183 }
 184
 185 void Text::build(const Part &part, State state, const Geometry &parent, PartCache &cache) const
 186 {
 187         build(part, state, parent, 0, cache);
 188 }
 189
 190 void Text::build(const Part &part, State state, const Geometry &parent, unsigned first_row, PartCache &cache) const
 191 {
 192         if(!style || lines.empty())
 193                 return;
 194
 195         const GL::Font &font = style->get_font();
 196         GL::MeshBuilder bld(cache.create_mesh(part, font.get_texture()));
 197         bld.color(style->get_font_color(state));
 198
 199         RenderData data;
 200         data.bld = &bld;
 201
 202         process_lines(part, parent, first_row, &Text::build_line, data);
 203 }
 204
 205 Text &Text::operator=(const string &t)
 206 {
 207         set(t);
 208         return *this;
 209 }
 210
 211 void Text::find_lines()
 212 {
 213         lines.clear();
 214         float font_size = (style ? style->get_font_size() : 1);
 215         string::size_type start = 0;
 216         while(1)
 217         {
 218                 string::size_type newline = text.find('\n', start);
 219
 220                 Line line;
 221                 line.start = start;
 222                 line.length = (newline==string::npos ? text.size() : newline)-start;
 223                 line.width = line.length;
 224                 if(style)
 225                 {
 226                         string str = text.substr(line.start, line.length);
 227                         line.width = static_cast<unsigned>(style->get_font().get_string_width(str)*font_size);
 228                 }
 229                 lines.push_back(line);
 230
 231                 if(newline==string::npos)
 232                         break;
 233                 start = newline+1;
 234         }
 235 }
 236
 237 template<typename T>
 238 void Text::process_lines(const Part &part, const Geometry &parent, unsigned first_row, void (Text::*func)(unsigned, const Geometry &, T &) const, T &data) const
 239 {
 240         if(!style)
 241                 return;
 242
 243         const GL::Font &font = style->get_font();
 244         float font_size = style->get_font_size();
 245         unsigned line_spacing = static_cast<unsigned>(font_size*6/5);
 246         int y_offset = static_cast<int>(-font.get_descent()*font_size);
 247
 248         unsigned fit_height;
 249         unsigned n_lines = get_visible_lines(part, parent, &fit_height);
 250         first_row = min<unsigned>(first_row, lines.size()-n_lines);
 251
 252         for(unsigned i=0; i<n_lines; ++i)
 253         {
 254                 const Line &line = lines[first_row+i];
 255
 256                 Geometry rgeom;
 257                 rgeom.w = line.width;
 258                 rgeom.h = fit_height;
 259                 rgeom.y = (n_lines-1-i)*line_spacing+y_offset;
 260                 part.get_alignment().apply(rgeom, parent, part.get_margin());
 261
 262                 (this->*func)(first_row+i, rgeom, data);
 263         }
 264 }
 265
 266 void Text::build_line(unsigned i, const Geometry &rgeom, RenderData &data) const
 267 {
 268         const Line &line = lines[i];
 269
 270         GL::MatrixStack::Push _pushm(data.bld->matrix());
 271         data.bld->matrix() *= GL::Matrix::translation(rgeom.x, rgeom.y, 0);
 272         data.bld->matrix() *= GL::Matrix::scaling(style->get_font_size());
 273
 274         style->get_font().build_string(text.substr(line.start, line.length), *data.bld);
 275 }
 276
 277 void Text::coords_to_geom_line(unsigned i, const Geometry &rgeom, CoordsToGeomData &data) const
 278 {
 279         if(i==data.row)
 280         {
 281                 float w = style->get_font().get_string_width(text.substr(lines[i].start, data.col));
 282                 data.result = rgeom;
 283                 data.result.x += static_cast<unsigned>(w*style->get_font_size());
 284         }
 285 }
 286
 287 } // namespace GLtk
 288 } // namespace Msp