Support multiline text editing

[libs/gltk.git] / source / text.cpp

diff --git a/source/text.cpp b/source/text.cpp
index 31db228071943fc55f0f3942b16a32a50dcb3c90..d18d7b5ba6c03fc233026afd178220d30b2babe0 100644 (file)
--- a/source/text.cpp
+++ b/source/text.cpp
@@ -1,3 +1,10 @@
+/* $Id$
+
+This file is part of libmspgltk
+Copyright © 2009-2010  Mikko Rasa, Mikkosoft Productions
+Distributed under the LGPL
+*/
+
 #include <msp/gl/immediate.h>
 #include <msp/gl/matrix.h>
 #include "style.h"
@@ -86,6 +93,63 @@ void Text::insert(unsigned pos, const string &s)
        }
 }
 
+unsigned Text::get_line_length(unsigned i) const
+{
+       if(i>=lines.size())
+               throw InvalidParameterValue("Invalid line number");
+       return lines[i].length;
+}
+
+void Text::offset_to_coords(unsigned offs, unsigned &row, unsigned &col) const
+{
+       if(lines.empty())
+       {
+               row=0;
+               col=0;
+               return;
+       }
+
+       for(unsigned i=0; i<lines.size(); ++i)
+               if(offs>=lines[i].start && offs<=lines[i].start+lines[i].length)
+               {
+                       row=i;
+                       col=offs-lines[i].start;
+                       return;
+               }
+}
+
+unsigned Text::coords_to_offset(unsigned row, unsigned col) const
+{
+       if(row>=lines.size())
+               return text.size();
+
+       return lines[row].start+min(col, lines[row].length);
+}
+
+Geometry Text::coords_to_geometry(unsigned row, unsigned col) const
+{
+       if(row>=lines.size())
+               row=lines.size()-1;
+       const Line &line=lines[row];
+       if(col>line.length)
+               col=line.length;
+
+       const GL::Font *font=style->get_font();
+       float font_size=font->get_default_size();
+       unsigned line_height=static_cast<unsigned>((font->get_ascent()-font->get_descent())*font_size);
+       unsigned line_spacing=static_cast<unsigned>(font_size*6/5);
+       unsigned height=line_height+(lines.size()-1)*line_spacing;
+       int y_offset=static_cast<int>(-font->get_descent()*font_size);
+
+       Geometry geom;
+       geom.w=line.width;
+       geom.h=height;
+       geom.x=static_cast<unsigned>(font->get_string_width(text.substr(line.start, col))*font_size);
+       geom.y=(lines.size()-1-row)*line_spacing+y_offset;
+
+       return geom;
+}
+
 void Text::render(const Part &part, const Geometry &geom) const
 {
        if(lines.empty())
@@ -94,7 +158,7 @@ void Text::render(const Part &part, const Geometry &geom) const
        const GL::Font *font=style->get_font();
        float font_size=font->get_default_size();
        unsigned line_height=static_cast<unsigned>((font->get_ascent()-font->get_descent())*font_size);
-       unsigned line_spacing=font_size*6/5;
+       unsigned line_spacing=static_cast<unsigned>(font_size*6/5);
        unsigned height=line_height+(lines.size()-1)*line_spacing;
        int y_offset=static_cast<int>(-font->get_descent()*font_size);