source: orxonox.OLD/trunk/src/lib/graphics/text_engine/font_data.cc

/*
   orxonox - the future of 3D-vertical-scrollers

   Copyright (C) 2004 orx

   This program is free software; you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
   the Free Software Foundation; either version 2, or (at your option)
   any later version.

   ### File Specific:
   main-programmer: Benjamin Grauer
   co-programmer: ...
*/

#define DEBUG_SPECIAL_MODULE DEBUG_MODULE_IMPORTER

#include "font_data.h"

#include "debug.h"
#include "compiler.h"

#include "texture.h"


/**
 * @brief creates a new Font Data.
 */
FontData::FontData()
    : texData(new TextureData)
{
  this->glyphArray = NULL;
  this->renderStyle = TTF_STYLE_NORMAL;
  this->renderSize = FONT_DEFAULT_RENDER_SIZE;

  this->maxHeight = 0;
  this->maxAscent = 0;
  this->maxDescent = 0;
}


/**
 * @brief Destructor of a Font
 *
 *  Frees Data, and deletes the fonts from GL
 */
FontData::~FontData()
{
  // deleting all Glyphs
  if (this->glyphArray != NULL)
  {
    for (int i = 0; i < FONT_HIGHEST_KNOWN_CHAR; i++)
    {
      if (this->glyphArray[i] != NULL)
        delete this->glyphArray[i];
    }
    delete[] this->glyphArray;
  }

  //! @todo check if we really do not need to delete the fastTextureID here.
  //   if (this->fastTextureID != 0)
  //     if(glIsTexture(this->fastTextureID))
  //       glDeleteTextures(1, &this->fastTextureID);
}


/**
 * @brief sets The Font.
 * @param fontFile The file containing the font.
 * @returns true if loaded, false if something went wrong, or if a font was loaded before.
 */
bool FontData::loadFontFromTTF(const std::string& fontFile, unsigned int renderSize)
{
  TTF_Font* fontTTF;
  //this->setName(fontFile);
  fontTTF = TTF_OpenFont(fontFile.c_str(), renderSize);
  this->renderSize = renderSize;

  if(fontTTF != NULL)
  {
    this->maxHeight = TTF_FontHeight(fontTTF);
    this->maxAscent = TTF_FontAscent(fontTTF);
    this->maxDescent = TTF_FontDescent(fontTTF);

    this->setStyle(fontTTF, "c");
    if (this->createFastTexture(fontTTF))
    {
      TTF_CloseFont(fontTTF);
      return true;
    }

    else
    {
      TTF_CloseFont(fontTTF);
      PRINTF(1)("Unable to createa a Fast Texture fot %s\n", fontFile.c_str() );
      return false;
    }
  }
  else
  {
    PRINTF(1)("TTF_OpenFont: %s for %s\n", TTF_GetError(), fontFile.c_str());
    return false;
  }

}



/**
 * @brief loads a font From an XPM-array.
 * @param xpmArray the array of the XPM to load the font from.
 */
bool FontData::loadFontFromSDL_Surface(SDL_Surface* surface)
{
  if(surface == NULL)
    return false;


  bool hasAlpha;
  SDL_Surface* newSurf = Texture::prepareSurface(surface, hasAlpha);
  if (newSurf != NULL)
  {
    this->texData->setSurface(newSurf);
    this->texData->setAlpha(hasAlpha);
    this->texData->setTexture(Texture::loadTexToGL(newSurf));
  }
  else
  {
    return false;
  }

  // initializing the Glyphs.
  if (this->glyphArray == NULL)
  {
    float cx,cy;
    Glyph* tmpGlyph;
    this->glyphArray = new Glyph*[FONT_HIGHEST_KNOWN_CHAR];
    for (int i = 0; i < FONT_HIGHEST_KNOWN_CHAR; i++)
    {
      tmpGlyph = this->glyphArray[i] = new Glyph;
      cx=(float)(i%16)/16.0f;                  // X Position Of Current Character
      cy=(float)(i/16)/16.0f;                  // Y Position Of Current Character

      tmpGlyph->texCoord[0] = cx;
      tmpGlyph->texCoord[1] = cx+0.0625f;
      tmpGlyph->texCoord[2] = cy;
      tmpGlyph->texCoord[3] = cy+0.0625f;
      tmpGlyph->minX = 0.0f;
      tmpGlyph->maxX = 1.0f;
      tmpGlyph->minY = 0.0f;
      tmpGlyph->maxY = 1.0f;
      tmpGlyph->width = 1.0f;
      tmpGlyph->advance = 1.0f;
      tmpGlyph->bearingX = 0.0f;
      tmpGlyph->bearingY = 0.0f;
      tmpGlyph->height = 1.0f;
    }
  }
  return true;
}

/**
 * @brief sets a specific data->renderStyle
 * @param data->renderStyle the Style to render: a string (char-array) containing:
 *   i: italic, b: bold, u, underline
 */
void FontData::setStyle(TTF_Font* font, const std::string& renderStyle)
{
  this->renderStyle = TTF_STYLE_NORMAL;

  for (unsigned int i = 0; i < renderStyle.size(); i++)
  {
    if (renderStyle[i] == 'b')
      this->renderStyle |= TTF_STYLE_BOLD;
    else if (renderStyle[i] == 'i')
      this->renderStyle |= TTF_STYLE_ITALIC;
    else if (renderStyle[i] == 'u')
      this->renderStyle |= TTF_STYLE_UNDERLINE;
  }

  /// !TODO REBUILD THE FONT

  if (likely(font != NULL))
      TTF_SetFontStyle(font, this->renderStyle);
  //  else
  //    PRINTF(2)("Font was not initialized, please do so before setting the Font-Style.\n");
}



/**
 * @param glyph: The Glyph to set the Parameters to.
 * @param character: The character to get info about.
 * @returns a Glyph struct of a character. This Glyph is a pointer,
 * and MUST be deleted by the user..
 *
 * This only works for horizontal fonts. see
 * http://freetype.sourceforge.net/freetype2/docs/tutorial/step2.html
 * for more info about vertical Fonts
 */
bool FontData::getGlyphMetrics(TTF_Font* font, Glyph* glyph, Uint16 character)
{
  glyph->character = character;
  if (likely (font != NULL))
  {
    int miX, maX, miY, maY, adv;
    if (TTF_GlyphMetrics(font, glyph->character,
                         &miX, &maX,
                         &miY, &maY,
                         &adv) == -1)
      return false;
    glyph->minX = (float)miX / (float)this->renderSize;
    glyph->maxX = (float)maX / (float)this->renderSize;
    glyph->minY = (float)miY / (float)this->renderSize;
    glyph->maxY = (float)maY / (float)this->renderSize;
    glyph->advance = (float)adv / (float)this->renderSize;

    // Calculate the Rest.
    glyph->height = glyph->maxY - glyph->minY;
    glyph->width = glyph->maxX - glyph->minX;
    glyph->bearingX = (glyph->advance - glyph->width) / 2;
    glyph->bearingY = glyph->maxY;

    //printf("%c:: %d %d %d %d %d\n", character, miX, maX, miY, maY, adv);

    return true;
  }
  return false;
}


/**
 * @brief creates a Fast-Texture of this Font
 */
bool FontData::createFastTexture(TTF_Font* fontTTF)
{
  /* interesting GLYPHS:
  *  32: space
  *  33-47: Special Characters.
  *  48-57: 0-9
  *  58-63: some more special chars (minor)
  *  65-90: A-Z
  *  97-122: a-z
  */
  int numberOfGlyphs = 91;

  this->initGlyphs(fontTTF, 32, numberOfGlyphs);
  //  this->glyphArray[32]->width = .5f; //!< @todo find out the real size of a Space

  int rectSize = this->findOptimalFastTextureSize();

  // setting default values. (maybe not needed afterwards)
  SDL_Color tmpColor;  tmpColor.r = tmpColor.g = tmpColor.b = 0;
  // Surface definition.
  SDL_Rect tmpRect; // this represents a Rectangle for blitting.
  SDL_Surface* tmpSurf =  SDL_CreateRGBSurface(SDL_HWSURFACE,
                          rectSize, rectSize,
                          32,
#if SDL_BYTEORDER == SDL_LIL_ENDIAN /* OpenGL RGBA masks */
                          0x000000FF,
                          0x0000FF00,
                          0x00FF0000,
                          0xFF000000
#else
                          0xFF000000,
                          0x00FF0000,
                          0x0000FF00,
                          0x000000FF
#endif
                                              );
  tmpRect.x = 0; tmpRect.y = 0; tmpRect.w = tmpSurf->w; tmpRect.h = tmpSurf->h;
  SDL_SetClipRect(tmpSurf, &tmpRect);
  int maxLineHeight = this->getMaxHeight();

  // all the interessting Glyphs
  for (int i = 0; i < 128; i++)
  {
    SDL_Surface* glyphSurf = NULL;
    Glyph* tmpGlyph;

    if ((tmpGlyph = this->glyphArray[i]) != NULL)
    {
      if (tmpGlyph->height*this->renderSize > maxLineHeight)
        maxLineHeight = (int)(tmpGlyph->height*this->renderSize);

      if (tmpRect.x+tmpGlyph->advance*this->renderSize > tmpSurf->w)
      {
        tmpRect.x = 0;
        tmpRect.y = tmpRect.y + maxLineHeight;
      }
      if (tmpRect.y + maxLineHeight > tmpSurf->h)
      {
        PRINTF(1)("Protection, so font cannot write over the boundraries (!!this should not heappen!!)\n");
        break;
      }
      // reading in the new Glyph
      if (likely(fontTTF != NULL))
      {
        SDL_Color white = {255, 255, 255};
        glyphSurf = TTF_RenderGlyph_Blended(fontTTF, i, white);
      }
      if( glyphSurf != NULL )
      {
        SDL_SetAlpha(glyphSurf, 0, 0);
        int tmpY = tmpRect.y;
        tmpRect.y += this->getMaxAscent()-(int)((float)tmpGlyph->bearingY*this->renderSize);
        SDL_BlitSurface(glyphSurf, NULL, tmpSurf, &tmpRect);
        tmpRect.y = tmpY;

        tmpGlyph->texCoord[0] = (float)((float)tmpRect.x )/(float)tmpSurf->w;
        tmpGlyph->texCoord[1] = (float)((float)tmpRect.x + tmpGlyph->width*(float)this->renderSize)/(float)tmpSurf->w;
        tmpGlyph->texCoord[2] = (float)(tmpRect.y)/(float)tmpSurf->w;
        tmpGlyph->texCoord[3] = (float)((float)tmpRect.y+(float)this->getMaxHeight())/(float)tmpSurf->w;
        SDL_FreeSurface(glyphSurf);
        tmpRect.x += (int)(tmpGlyph->width * this->renderSize) + 1;
      }
    }
  }
  // outputting the GLYPH-table
  //       char outName[1024];
  //       sprintf( outName, "%s-glyphs.bmp", this->getName());
  //       SDL_SaveBMP(tmpSurf, outName);
  this->texData->setAlpha(true);
  if (this->texData->setSurface(tmpSurf))
    this->texData->setTexture(Texture::loadTexToGL(tmpSurf));
  return true;
}

/**
 * @brief stores Glyph Metrics in an Array.
 * @param from The Glyph to start from.
 * @param count The number of Glyphs to start From.
 */
void FontData::initGlyphs(TTF_Font* font, Uint16 from, Uint16 count)
{
  /* initialize the Array, and set all its entries to NULL
  *  only if the Glyph-array has not been initialized
  */
  if (!this->glyphArray)
  {
    this->glyphArray = new Glyph*[FONT_HIGHEST_KNOWN_CHAR];
    for (int i = 0; i < FONT_HIGHEST_KNOWN_CHAR; i++)
      this->glyphArray[i] = NULL;
  }

  Uint16 lastGlyph = from + count;

  for (int i = from; i <= lastGlyph; i++)
  {
    // setting up all the Glyphs we like.
    Glyph* newGlyph = new Glyph;
    if (getGlyphMetrics(font, newGlyph, i))
      this->glyphArray[i] = newGlyph;
    else
    {
      delete newGlyph;
      this->glyphArray[i] = NULL;
    }
  }
  return;
}

/**
 * @returns the optimal size to use as the texture size
 *
 * @todo: this algorithm can be a lot faster, althought it does
 * not really matter within the init-context, and 128 glyphs.
 *
 * This function searches for a 2^n sizes texture-size, this is for
 * openGL-version < 1.2 compatibility ( and because it is realy easy like this :))
 */
int FontData::findOptimalFastTextureSize()
{
  if (this->glyphArray == NULL)
    return 0;

  unsigned int i;
  unsigned int x,y; // the counters
  int maxLineHeight = this->getMaxHeight();
  unsigned int size = 32;  // starting Value, we have to start somewhere 32 seems reasonable. (take any small enough 2^i number)
  bool sizeOK = false;
  Glyph* tmpGlyph;

  while (!sizeOK)
  {
    x = 0; y = 0;
    for (i = 0; i < FONT_HIGHEST_KNOWN_CHAR; i++)
    {
      if((tmpGlyph = this->glyphArray[i]) != NULL)
      {
        // getting the height of the highest Glyph in the Line.
        if (tmpGlyph->height*this->renderSize > maxLineHeight)
          maxLineHeight = (int)(tmpGlyph->height*this->renderSize);

        if (x + tmpGlyph->advance*this->renderSize > size)
        {
          x = 0;
          y = y + maxLineHeight;
          //maxLineHeight = 0;
        }
        if (y + maxLineHeight + 1 > size)
          break;
        x += (int)(tmpGlyph->advance*this->renderSize)+1;

      }
    }
    if (i >= FONT_HIGHEST_KNOWN_CHAR-1 || size > 8192)
      sizeOK = true;
    else
      size *= 2;
  }
  return size;
}