tr_font.c

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				dst += 256;
	    }
		}

    // we now have an 8 bit per pixel grey scale bitmap 
    // that is width wide and pf->ftSize->metrics.y_ppem tall

    glyph.imageHeight = scaled_height;
    glyph.imageWidth = scaled_width;
    glyph.s = (float)*xOut / 256;
    glyph.t = (float)*yOut / 256;
    glyph.s2 = glyph.s + (float)scaled_width / 256;
    glyph.t2 = glyph.t + (float)scaled_height / 256;

    *xOut += scaled_width + 1;
  }

  Z_Free(bitmap->buffer);
  Z_Free(bitmap);

  return &glyph;
}
#endif

static int fdOffset;
static byte	*fdFile;

int readInt() {
	int i = fdFile[fdOffset]+(fdFile[fdOffset+1]<<8)+(fdFile[fdOffset+2]<<16)+(fdFile[fdOffset+3]<<24);
	fdOffset += 4;
	return i;
}

typedef union {
	byte	fred[4];
	float	ffred;
} poor;

float readFloat() {
	poor	me;
#if idppc
	me.fred[0] = fdFile[fdOffset+3];
	me.fred[1] = fdFile[fdOffset+2];
	me.fred[2] = fdFile[fdOffset+1];
	me.fred[3] = fdFile[fdOffset+0];
#else
	me.fred[0] = fdFile[fdOffset+0];
	me.fred[1] = fdFile[fdOffset+1];
	me.fred[2] = fdFile[fdOffset+2];
	me.fred[3] = fdFile[fdOffset+3];
#endif
	fdOffset += 4;
	return me.ffred;
}

void RE_RegisterFont(const char *fontName, int pointSize, fontInfo_t *font) {
#ifdef BUILD_FREETYPE
  FT_Face face;
  int j, k, xOut, yOut, lastStart, imageNumber;
  int scaledSize, newSize, maxHeight, left, satLevels;
  unsigned char *out, *imageBuff;
  glyphInfo_t *glyph;
  image_t *image;
  qhandle_t h;
	float max;
#endif
  void *faceData;
	int i, len;
  char name[1024];
	float dpi = 72;											//
	float glyphScale =  72.0f / dpi; 		// change the scale to be relative to 1 based on 72 dpi ( so dpi of 144 means a scale of .5 )

	if (pointSize <= 0) {
		pointSize = 12;
	}
	// we also need to adjust the scale based on point size relative to 48 points as the ui scaling is based on a 48 point font
	glyphScale *= 48.0f / pointSize;

	// make sure the render thread is stopped
	R_SyncRenderThread();

  if (registeredFontCount >= MAX_FONTS) {
    ri.Printf(PRINT_ALL, "RE_RegisterFont: Too many fonts registered already.\n");
    return;
  }

	Com_sprintf(name, sizeof(name), "fonts/fontImage_%i.dat",pointSize);
	for (i = 0; i < registeredFontCount; i++) {
		if (Q_stricmp(name, registeredFont[i].name) == 0) {
			Com_Memcpy(font, &registeredFont[i], sizeof(fontInfo_t));
			return;
		}
	}

	len = ri.FS_ReadFile(name, NULL);
	if (len == sizeof(fontInfo_t)) {
		ri.FS_ReadFile(name, &faceData);
		fdOffset = 0;
		fdFile = faceData;
		for(i=0; i<GLYPHS_PER_FONT; i++) {
			font->glyphs[i].height		= readInt();
			font->glyphs[i].top			= readInt();
			font->glyphs[i].bottom		= readInt();
			font->glyphs[i].pitch		= readInt();
			font->glyphs[i].xSkip		= readInt();
			font->glyphs[i].imageWidth	= readInt();
			font->glyphs[i].imageHeight = readInt();
			font->glyphs[i].s			= readFloat();
			font->glyphs[i].t			= readFloat();
			font->glyphs[i].s2			= readFloat();
			font->glyphs[i].t2			= readFloat();
			font->glyphs[i].glyph		= readInt();
			Com_Memcpy(font->glyphs[i].shaderName, &fdFile[fdOffset], 32);
			fdOffset += 32;
		}
		font->glyphScale = readFloat();
		Com_Memcpy(font->name, &fdFile[fdOffset], MAX_QPATH);

//		Com_Memcpy(font, faceData, sizeof(fontInfo_t));
		Q_strncpyz(font->name, name, sizeof(font->name));
		for (i = GLYPH_START; i < GLYPH_END; i++) {
			font->glyphs[i].glyph = RE_RegisterShaderNoMip(font->glyphs[i].shaderName);
		}
	  Com_Memcpy(&registeredFont[registeredFontCount++], font, sizeof(fontInfo_t));
		return;
	}

#ifndef BUILD_FREETYPE
    ri.Printf(PRINT_ALL, "RE_RegisterFont: FreeType code not available\n");
#else
  if (ftLibrary == NULL) {
    ri.Printf(PRINT_ALL, "RE_RegisterFont: FreeType not initialized.\n");
    return;
  }

  len = ri.FS_ReadFile(fontName, &faceData);
  if (len <= 0) {
    ri.Printf(PRINT_ALL, "RE_RegisterFont: Unable to read font file\n");
    return;
  }

  // allocate on the stack first in case we fail
  if (FT_New_Memory_Face( ftLibrary, faceData, len, 0, &face )) {
    ri.Printf(PRINT_ALL, "RE_RegisterFont: FreeType2, unable to allocate new face.\n");
    return;
  }


  if (FT_Set_Char_Size( face, pointSize << 6, pointSize << 6, dpi, dpi)) {
    ri.Printf(PRINT_ALL, "RE_RegisterFont: FreeType2, Unable to set face char size.\n");
    return;
  }

  //*font = &registeredFonts[registeredFontCount++];

  // make a 256x256 image buffer, once it is full, register it, clean it and keep going 
  // until all glyphs are rendered

  out = Z_Malloc(1024*1024);
  if (out == NULL) {
    ri.Printf(PRINT_ALL, "RE_RegisterFont: Z_Malloc failure during output image creation.\n");
    return;
  }
  Com_Memset(out, 0, 1024*1024);

  maxHeight = 0;

  for (i = GLYPH_START; i < GLYPH_END; i++) {
    glyph = RE_ConstructGlyphInfo(out, &xOut, &yOut, &maxHeight, face, (unsigned char)i, qtrue);
  }

  xOut = 0;
  yOut = 0;
  i = GLYPH_START;
  lastStart = i;
  imageNumber = 0;

  while ( i <= GLYPH_END ) {

    glyph = RE_ConstructGlyphInfo(out, &xOut, &yOut, &maxHeight, face, (unsigned char)i, qfalse);

    if (xOut == -1 || yOut == -1 || i == GLYPH_END)  {
      // ran out of room
      // we need to create an image from the bitmap, set all the handles in the glyphs to this point
      // 

      scaledSize = 256*256;
      newSize = scaledSize * 4;
      imageBuff = Z_Malloc(newSize);
      left = 0;
      max = 0;
      satLevels = 255;
      for ( k = 0; k < (scaledSize) ; k++ ) {
        if (max < out[k]) {
          max = out[k];
        }
      }

			if (max > 0) {
				max = 255/max;
			}

      for ( k = 0; k < (scaledSize) ; k++ ) {
        imageBuff[left++] = 255;
        imageBuff[left++] = 255;
        imageBuff[left++] = 255;

        imageBuff[left++] = ((float)out[k] * max);
      }

			Com_sprintf (name, sizeof(name), "fonts/fontImage_%i_%i.tga", imageNumber++, pointSize);
			if (r_saveFontData->integer) { 
			  WriteTGA(name, imageBuff, 256, 256);
			}

    	//Com_sprintf (name, sizeof(name), "fonts/fontImage_%i_%i", imageNumber++, pointSize);
      image = R_CreateImage(name, imageBuff, 256, 256, qfalse, qfalse, GL_CLAMP);
      h = RE_RegisterShaderFromImage(name, LIGHTMAP_2D, image, qfalse);
      for (j = lastStart; j < i; j++) {
        font->glyphs[j].glyph = h;
				Q_strncpyz(font->glyphs[j].shaderName, name, sizeof(font->glyphs[j].shaderName));
      }
      lastStart = i;
		  Com_Memset(out, 0, 1024*1024);
      xOut = 0;
      yOut = 0;
      Z_Free(imageBuff);
			i++;
    } else {
      Com_Memcpy(&font->glyphs[i], glyph, sizeof(glyphInfo_t));
      i++;
    }
  }

	registeredFont[registeredFontCount].glyphScale = glyphScale;
	font->glyphScale = glyphScale;
  Com_Memcpy(&registeredFont[registeredFontCount++], font, sizeof(fontInfo_t));

	if (r_saveFontData->integer) { 
		ri.FS_WriteFile(va("fonts/fontImage_%i.dat", pointSize), font, sizeof(fontInfo_t));
	}

  Z_Free(out);
  
  ri.FS_FreeFile(faceData);
#endif
}



void R_InitFreeType() {
#ifdef BUILD_FREETYPE
  if (FT_Init_FreeType( &ftLibrary )) {
    ri.Printf(PRINT_ALL, "R_InitFreeType: Unable to initialize FreeType.\n");
  }
#endif
  registeredFontCount = 0;
}


void R_DoneFreeType() {
#ifdef BUILD_FREETYPE
  if (ftLibrary) {
    FT_Done_FreeType( ftLibrary );
    ftLibrary = NULL;
  }
#endif
	registeredFontCount = 0;
}