Files
OpenSceneGraph/src/osgPlugins/txf/TXFFont.cpp

299 lines
8.6 KiB
C++

/* -*-c++-*- OpenSceneGraph - Copyright (C) 2006 Mathias Froehlich
*
* This library is open source and may be redistributed and/or modified under
* the terms of the OpenSceneGraph Public License (OSGPL) version 0.0 or
* (at your option) any later version. The full license is in LICENSE file
* included with this distribution, and on the openscenegraph.org website.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* OpenSceneGraph Public License for more details.
*/
#include "TXFFont.h"
#include <iostream>
#include <osg/Notify>
#define FNT_BYTE_FORMAT 0
#define FNT_BITMAP_FORMAT 1
struct GlyphData {
unsigned short ch;
unsigned char width;
unsigned char height;
signed char x_off;
signed char y_off;
signed char advance;
short x;
short y;
};
static inline void swap(unsigned short& x, bool isSwapped)
{
if (!isSwapped)
return;
x = ((x >> 8) & 0x00FF) | ((x << 8) & 0xFF00);
}
static inline void swap(unsigned& x, bool isSwapped)
{
if (!isSwapped)
return;
x = ((x >> 24) & 0x000000FF) | ((x >> 8) & 0x0000FF00) | ((x << 8) & 0x00FF0000) | ((x << 24) & 0xFF000000);
}
static inline unsigned char readByte(std::istream& stream)
{
unsigned char x;
stream.read(reinterpret_cast<std::istream::char_type*>(&x), 1);
return x;
}
static inline unsigned short readShort(std::istream& stream, bool isSwapped)
{
unsigned short x;
stream.read(reinterpret_cast<std::istream::char_type*>(&x), 2);
swap(x, isSwapped);
return x;
}
static inline unsigned readInt(std::istream& stream, bool isSwapped)
{
unsigned x;
stream.read(reinterpret_cast<std::istream::char_type*>(&x), 4);
swap(x, isSwapped);
return x;
}
TXFFont::TXFFont(const std::string& filename):
_filename(filename)
{
}
TXFFont::~TXFFont()
{
}
std::string
TXFFont::getFileName() const
{
return _filename;
}
osgText::Font::Glyph*
TXFFont::getGlyph(const osgText::FontResolution&, unsigned int charcode)
{
GlyphMap::iterator i = _chars.find(charcode);
if (i != _chars.end())
return i->second.get();
// ok, not available, we have an additional chance with some translations
// That is to make the loader compatible with an other prominent one
if (charcode >= 'A' && charcode <= 'Z')
{
i = _chars.find(charcode - 'A' + 'a');
if (i != _chars.end())
{
_chars[charcode] = i->second;
addGlyph(osgText::FontResolution(i->second->s(), i->second->t()), charcode, i->second.get());
return i->second.get();
}
}
else if (charcode >= 'a' && charcode <= 'z')
{
i = _chars.find(charcode - 'a' + 'A');
if (i != _chars.end())
{
_chars[charcode] = i->second;
addGlyph(osgText::FontResolution(i->second->s(), i->second->t()), charcode, i->second.get());
return i->second.get();
}
}
return 0;
}
bool
TXFFont::hasVertical() const
{
return true;
}
osg::Vec2
TXFFont::getKerning(const osgText::FontResolution&, unsigned int, unsigned int, osgText::KerningType)
{
return osg::Vec2(0, 0);
}
bool
TXFFont::loadFont(std::istream& stream)
{
unsigned char magic[4];
stream.read(reinterpret_cast<std::istream::char_type*>(&magic), 4);
if (magic[0] != 0xFF || magic[1] != 't' || magic[2] != 'x' || magic[3] != 'f' )
{
osg::notify(osg::FATAL) << "osgdb_txf: input file \"" << _filename << "\" is not a texture font file!" << std::endl;
return false;
}
// read endianess hint
bool isSwapped = 0x12345678u != readInt(stream, false);
unsigned format = readInt(stream, isSwapped);
unsigned texwidth = readInt(stream, isSwapped);
unsigned texheight = readInt(stream, isSwapped);
unsigned maxheight = readInt(stream, isSwapped);
readInt(stream, isSwapped);
unsigned num_glyphs = readInt(stream, isSwapped);
unsigned maxwidth = 0;
unsigned w = texwidth;
unsigned h = texheight;
osgText::FontResolution fontResolution(maxheight, maxheight);
std::vector<GlyphData> glyphs;
for (unsigned i = 0; i < num_glyphs; ++i)
{
GlyphData glyphData;
glyphData.ch = readShort(stream, isSwapped);
glyphData.width = readByte(stream);
glyphData.height = readByte(stream);
glyphData.x_off = readByte(stream);
glyphData.y_off = readByte(stream);
glyphData.advance = readByte(stream);
readByte(stream);
glyphData.x = readShort(stream, isSwapped);
glyphData.y = readShort(stream, isSwapped);
maxwidth = std::max(maxwidth, (unsigned)glyphData.width);
glyphs.push_back(glyphData);
}
unsigned ntexels = w * h;
osg::ref_ptr<osg::Image> image = new osg::Image;
image->allocateImage(w, h, 1, GL_ALPHA, GL_UNSIGNED_BYTE);
if (format == FNT_BYTE_FORMAT)
{
stream.read(reinterpret_cast<std::istream::char_type*>(image->data()), ntexels);
if (!stream)
{
osg::notify(osg::FATAL) << "osgdb_txf: unxpected end of file in txf file \"" << _filename << "\"!" << std::endl;
return false;
}
}
else if (format == FNT_BITMAP_FORMAT)
{
unsigned stride = (w + 7) >> 3;
unsigned char *texbitmap = new unsigned char[stride*h] ;
stream.read(reinterpret_cast<std::istream::char_type*>(texbitmap), stride*h);
if (!stream)
{
delete [] texbitmap;
osg::notify(osg::FATAL) << "osgdb_txf: unxpected end of file in txf file \"" << _filename << "\"!" << std::endl;
return false;
}
for (unsigned i = 0; i < h; i++)
{
for (unsigned j = 0; j < w; j++)
{
if (texbitmap[i * stride + (j >> 3)] & (1 << (j & 7)))
{
*image->data(j, i) = 255;
}
else
{
*image->data(j, i) = 0;
}
}
}
delete [] texbitmap;
}
else
{
osg::notify(osg::FATAL) << "osgdb_txf: unxpected txf file!" << std::endl;
return false;
}
for (unsigned i = 0; i < glyphs.size(); ++i)
{
// have a special one for that
if (glyphs[i].ch == ' ')
continue;
// add the characters ...
osgText::Font::Glyph* glyph = new osgText::Font::Glyph(glyphs[i].ch);
unsigned sourceWidth = glyphs[i].width;
unsigned sourceHeight = glyphs[i].height;
unsigned width = sourceWidth;
unsigned height = sourceHeight;
glyph->allocateImage(width, height, 1, GL_ALPHA, GL_UNSIGNED_BYTE);
glyph->setInternalTextureFormat(GL_ALPHA);
for (unsigned k = 0; k < width; ++k)
{
for (unsigned l = 0; l < height; ++l)
{
*glyph->data(k, l) = 0;
}
}
for (unsigned k = 0; k < glyphs[i].width; ++k)
{
for (unsigned l = 0; l < glyphs[i].height; ++l)
{
*glyph->data(k, l) = *image->data(glyphs[i].x + k, glyphs[i].y + l);
}
}
float texToVertX = float(glyphs[i].width)/width;
float texToVertY = float(glyphs[i].height)/height;
glyph->setHorizontalAdvance(glyphs[i].advance + 0.1f*maxheight);
glyph->setHorizontalBearing(osg::Vec2((glyphs[i].x_off - 0.5f)*texToVertX,
(glyphs[i].y_off - 0.5f)*texToVertY));
glyph->setVerticalAdvance(sourceHeight);
glyph->setVerticalBearing(osg::Vec2(glyphs[i].x_off*texToVertX - 0.5f*glyphs[i].advance*texToVertX,
- glyphs[i].height*texToVertY));
_chars[glyphs[i].ch] = glyph;
addGlyph(fontResolution, glyphs[i].ch, glyph);
}
// insert a trivial blank character
osgText::Font::Glyph* glyph = new osgText::Font::Glyph(' ');
unsigned width = 1;
unsigned height = 1;
glyph->allocateImage(width, height, 1, GL_ALPHA, GL_UNSIGNED_BYTE);
glyph->setInternalTextureFormat(GL_ALPHA);
for (unsigned k = 0; k < width; ++k)
{
for (unsigned l = 0; l < height; ++l)
{
*glyph->data(k, l) = 0;
}
}
glyph->setHorizontalAdvance(0.5f*float(fontResolution.second));
glyph->setHorizontalBearing(osg::Vec2(0.0f, 0.0f));
glyph->setVerticalAdvance(float(fontResolution.second));
glyph->setVerticalBearing(osg::Vec2(0.0f, 0.0f));
_chars[' '] = glyph;
addGlyph(fontResolution, ' ', glyph);
return true;
}