icuSources/samples/layout/GnomeFontInstance.cpp

   1
   2 /*
   3  *******************************************************************************
   4  *
   5  *   Copyright (C) 1999-2005, International Business Machines
   6  *   Corporation and others.  All Rights Reserved.
   7  *
   8  *******************************************************************************
   9  *   file name:  GnomeFontInstance.cpp
  10  *
  11  *   created on: 08/30/2001
  12  *   created by: Eric R. Mader
  13  */
  14
  15 #include <gnome.h>
  16 #include "freetype/freetype.h"
  17
  18 #include "layout/LETypes.h"
  19 #include "layout/LESwaps.h"
  20
  21 #include "GnomeFontInstance.h"
  22 #include "sfnt.h"
  23 #include "cmaps.h"
  24
  25 GnomeSurface::GnomeSurface(GtkWidget *theWidget)
  26     : fWidget(theWidget)
  27 {
  28     // nothing else to do
  29 }
  30
  31 GnomeSurface::~GnomeSurface()
  32 {
  33     // nothing to do
  34 }
  35
  36 void GnomeSurface::drawGlyphs(const LEFontInstance *font, const LEGlyphID *glyphs, le_int32 count,
  37                               const float *positions, le_int32 x, le_int32 y, le_int32 /*width*/, le_int32 /*height*/)
  38 {
  39     GnomeFontInstance *gFont = (GnomeFontInstance *) font;
  40     TT_Instance instance = gFont->getFont();
  41     le_int32 *dx = LE_NEW_ARRAY(le_int32, count);
  42     le_int32 *dy = LE_NEW_ARRAY(le_int32, count);
  43     le_int32 xOffset, yOffset;
  44     TT_Raster_Map *raster;
  45 //  TT_Error error;
  46
  47     for (le_int32 g = 0; g < count; g += 1) {
  48         dx[g] = (le_int32) (positions[g * 2 + 2] - positions[g * 2]);
  49         dy[g] = (le_int32) - positions[g * 2 + 1];
  50     }
  51
  52     raster = gFont->rasterizeGlyphs(glyphs, count, dx, dy, xOffset, yOffset);
  53
  54     if (raster->width > 0 && raster->rows > 0) {
  55         GdkBitmap *bitmap = gdk_bitmap_create_from_data(NULL, (const gchar *) raster->bitmap, raster->width, raster->rows);
  56
  57         gint bitsx = x + (gint) positions[0] + xOffset;
  58         gint bitsy = y - yOffset;
  59
  60         gdk_gc_set_clip_origin(fWidget->style->black_gc, bitsx, bitsy);
  61         gdk_gc_set_clip_mask(fWidget->style->black_gc, bitmap);
  62
  63         gdk_draw_rectangle(fWidget->window,
  64                            fWidget->style->black_gc,
  65                            TRUE,
  66                            bitsx, bitsy,
  67                            raster->width, raster->rows);
  68
  69         gdk_gc_set_clip_origin(fWidget->style->black_gc, 0, 0);
  70         gdk_gc_set_clip_mask(fWidget->style->black_gc, NULL);
  71
  72         gdk_bitmap_unref(bitmap);
  73     }
  74
  75     gFont->freeRaster(raster);
  76     LE_DELETE_ARRAY(dy);
  77     LE_DELETE_ARRAY(dx);
  78 }
  79
  80 GnomeFontInstance::GnomeFontInstance(TT_Engine engine, const TT_Text *fontPathName, le_int16 pointSize, LEErrorCode &status)
  81     : FontTableCache(), fPointSize(pointSize), fUnitsPerEM(0), fAscent(0), fDescent(0), fLeading(0),
  82       fDeviceScaleX(1), fDeviceScaleY(1), fMapper(NULL)
  83 {
  84     TT_Error error;
  85     TT_Face_Properties faceProperties;
  86
  87     fFace.z = NULL;
  88
  89     error = TT_Open_Face(engine, fontPathName, &fFace);
  90
  91     if (error != 0) {
  92         status = LE_FONT_FILE_NOT_FOUND_ERROR;
  93         return;
  94     }
  95
  96     error = TT_New_Instance(fFace, &fInstance);
  97
  98     if (error != 0) {
  99         status = LE_MEMORY_ALLOCATION_ERROR;
 100         return;
 101     }
 102
 103     // FIXME: what about the display resolution?
 104     // TT_Set_Instance_Resolutions(fInstance, 72, 72);
 105     fDeviceScaleX = ((float) 96) / 72;
 106     fDeviceScaleY = ((float) 96) / 72;
 107
 108     TT_Set_Instance_CharSize(fInstance, pointSize << 6);
 109
 110     TT_Get_Face_Properties(fFace, &faceProperties);
 111
 112     fUnitsPerEM = faceProperties.header->Units_Per_EM;
 113
 114     fAscent  = (le_int32) (yUnitsToPoints(faceProperties.horizontal->Ascender) * fDeviceScaleY);
 115     fDescent = (le_int32) -(yUnitsToPoints(faceProperties.horizontal->Descender) * fDeviceScaleY);
 116     fLeading = (le_int32) (yUnitsToPoints(faceProperties.horizontal->Line_Gap) * fDeviceScaleY);
 117
 118     // printf("Face = %s, unitsPerEM = %d, ascent = %d, descent = %d\n", fontPathName, fUnitsPerEM, fAscent, fDescent);
 119
 120     error = TT_New_Glyph(fFace, &fGlyph);
 121
 122     if (error != 0) {
 123         status = LE_MEMORY_ALLOCATION_ERROR;
 124         return;
 125     }
 126
 127     status = initMapper();
 128 }
 129
 130 GnomeFontInstance::~GnomeFontInstance()
 131 {
 132     if (fFace.z != NULL) {
 133         TT_Close_Face(fFace);
 134     }
 135 }
 136
 137 LEErrorCode GnomeFontInstance::initMapper()
 138 {
 139     LETag cmapTag = LE_CMAP_TABLE_TAG;
 140     const CMAPTable *cmap = (const CMAPTable *) readFontTable(cmapTag);
 141
 142     if (cmap == NULL) {
 143         return LE_MISSING_FONT_TABLE_ERROR;
 144     }
 145
 146     fMapper = CMAPMapper::createUnicodeMapper(cmap);
 147
 148     if (fMapper == NULL) {
 149         return LE_MISSING_FONT_TABLE_ERROR;
 150     }
 151
 152     return LE_NO_ERROR;
 153 }
 154
 155 const void *GnomeFontInstance::getFontTable(LETag tableTag) const
 156 {
 157     return FontTableCache::find(tableTag);
 158 }
 159
 160 const void *GnomeFontInstance::readFontTable(LETag tableTag) const
 161 {
 162     TT_Long len = 0;
 163     void *result = NULL;
 164
 165     TT_Get_Font_Data(fFace, tableTag, 0, NULL, &len);
 166
 167     if (len > 0) {
 168         result = LE_NEW_ARRAY(char, len);
 169         TT_Get_Font_Data(fFace, tableTag, 0, result, &len);
 170     }
 171
 172     return result;
 173 }
 174
 175 void GnomeFontInstance::getGlyphAdvance(LEGlyphID glyph, LEPoint &advance) const
 176 {
 177     advance.fX = 0;
 178     advance.fY = 0;
 179
 180     if (glyph >= 0xFFFE) {
 181         return;
 182     }
 183
 184     TT_Glyph_Metrics metrics;
 185     TT_Error error;
 186
 187     error = TT_Load_Glyph(fInstance, fGlyph, glyph, TTLOAD_SCALE_GLYPH | TTLOAD_HINT_GLYPH);
 188
 189     if (error != 0) {
 190         return;
 191     }
 192
 193     TT_Get_Glyph_Metrics(fGlyph, &metrics);
 194
 195     advance.fX = metrics.advance >> 6;
 196     return;
 197 }
 198
 199 le_bool GnomeFontInstance::getGlyphPoint(LEGlyphID glyph, le_int32 pointNumber, LEPoint &point) const
 200 {
 201     TT_Outline outline;
 202     TT_Error error;
 203
 204     error = TT_Load_Glyph(fInstance, fGlyph, glyph, TTLOAD_SCALE_GLYPH | TTLOAD_HINT_GLYPH);
 205
 206     if (error != 0) {
 207         return FALSE;
 208     }
 209
 210     error = TT_Get_Glyph_Outline(fGlyph, &outline);
 211
 212     if (error != 0 || pointNumber >= outline.n_points) {
 213         return FALSE;
 214     }
 215
 216     point.fX = outline.points[pointNumber].x >> 6;
 217     point.fY = outline.points[pointNumber].y >> 6;
 218
 219     return TRUE;
 220 }
 221
 222 // This table was generated by a little Java program.
 223 const char bitReverse[256] = {
 224     0x00, 0x80, 0x40, 0xC0, 0x20, 0xA0, 0x60, 0xE0, 0x10, 0x90, 0x50, 0xD0, 0x30, 0xB0, 0x70, 0xF0,
 225     0x08, 0x88, 0x48, 0xC8, 0x28, 0xA8, 0x68, 0xE8, 0x18, 0x98, 0x58, 0xD8, 0x38, 0xB8, 0x78, 0xF8,
 226     0x04, 0x84, 0x44, 0xC4, 0x24, 0xA4, 0x64, 0xE4, 0x14, 0x94, 0x54, 0xD4, 0x34, 0xB4, 0x74, 0xF4,
 227     0x0C, 0x8C, 0x4C, 0xCC, 0x2C, 0xAC, 0x6C, 0xEC, 0x1C, 0x9C, 0x5C, 0xDC, 0x3C, 0xBC, 0x7C, 0xFC,
 228     0x02, 0x82, 0x42, 0xC2, 0x22, 0xA2, 0x62, 0xE2, 0x12, 0x92, 0x52, 0xD2, 0x32, 0xB2, 0x72, 0xF2,
 229     0x0A, 0x8A, 0x4A, 0xCA, 0x2A, 0xAA, 0x6A, 0xEA, 0x1A, 0x9A, 0x5A, 0xDA, 0x3A, 0xBA, 0x7A, 0xFA,
 230     0x06, 0x86, 0x46, 0xC6, 0x26, 0xA6, 0x66, 0xE6, 0x16, 0x96, 0x56, 0xD6, 0x36, 0xB6, 0x76, 0xF6,
 231     0x0E, 0x8E, 0x4E, 0xCE, 0x2E, 0xAE, 0x6E, 0xEE, 0x1E, 0x9E, 0x5E, 0xDE, 0x3E, 0xBE, 0x7E, 0xFE,
 232     0x01, 0x81, 0x41, 0xC1, 0x21, 0xA1, 0x61, 0xE1, 0x11, 0x91, 0x51, 0xD1, 0x31, 0xB1, 0x71, 0xF1,
 233     0x09, 0x89, 0x49, 0xC9, 0x29, 0xA9, 0x69, 0xE9, 0x19, 0x99, 0x59, 0xD9, 0x39, 0xB9, 0x79, 0xF9,
 234     0x05, 0x85, 0x45, 0xC5, 0x25, 0xA5, 0x65, 0xE5, 0x15, 0x95, 0x55, 0xD5, 0x35, 0xB5, 0x75, 0xF5,
 235     0x0D, 0x8D, 0x4D, 0xCD, 0x2D, 0xAD, 0x6D, 0xED, 0x1D, 0x9D, 0x5D, 0xDD, 0x3D, 0xBD, 0x7D, 0xFD,
 236     0x03, 0x83, 0x43, 0xC3, 0x23, 0xA3, 0x63, 0xE3, 0x13, 0x93, 0x53, 0xD3, 0x33, 0xB3, 0x73, 0xF3,
 237     0x0B, 0x8B, 0x4B, 0xCB, 0x2B, 0xAB, 0x6B, 0xEB, 0x1B, 0x9B, 0x5B, 0xDB, 0x3B, 0xBB, 0x7B, 0xFB,
 238     0x07, 0x87, 0x47, 0xC7, 0x27, 0xA7, 0x67, 0xE7, 0x17, 0x97, 0x57, 0xD7, 0x37, 0xB7, 0x77, 0xF7,
 239     0x0F, 0x8F, 0x4F, 0xCF, 0x2F, 0xAF, 0x6F, 0xEF, 0x1F, 0x9F, 0x5F, 0xDF, 0x3F, 0xBF, 0x7F, 0xFF
 240 };
 241
 242 // FIXME: this would be much faster if we cached the TT_Glyph objects based on the glyph ID...
 243 TT_Raster_Map *GnomeFontInstance::rasterizeGlyphs(const LEGlyphID *glyphs, le_int32 glyphCount,
 244                                                   const le_int32 *dx, const le_int32 *dy, le_int32 &xOffset, le_int32 &yOffset) const
 245 {
 246     le_int32 i, xx = 0, yy = 0, zz;
 247     le_int32 minx = 0, maxx = 0, miny = 0, maxy = 0;
 248     TT_Raster_Map *raster = new TT_Raster_Map;
 249     TT_Glyph_Metrics metrics;
 250     TT_Error error;
 251
 252     for (i = 0; i < glyphCount; i += 1) {
 253         error = TT_Load_Glyph(fInstance, fGlyph, (TT_UShort) LE_GET_GLYPH(glyphs[i]), TTLOAD_SCALE_GLYPH | TTLOAD_HINT_GLYPH);
 254         if (error == 0) {
 255             TT_Get_Glyph_Metrics(fGlyph, &metrics);
 256
 257             zz = xx + metrics.bbox.xMin;
 258             if (minx > zz) {
 259                 minx = zz;
 260             }
 261
 262             zz = xx + metrics.bbox.xMax;
 263             if (maxx < zz) {
 264                 maxx = zz;
 265             }
 266
 267             yy = dy[i] * 64;
 268             zz = yy + metrics.bbox.yMin;
 269             if (miny > zz) {
 270                 miny = zz;
 271             }
 272
 273             zz = yy + metrics.bbox.yMax;
 274             if (maxy < zz) {
 275                 maxy = zz;
 276             }
 277         }
 278
 279         xx += (dx[i] * 64);
 280     }
 281
 282
 283     minx = (minx & -64) >> 6;
 284     miny = (miny & -64) >> 6;
 285
 286     maxx = ((maxx + 63) & -64) >> 6;
 287     maxy = ((maxy + 63) & -64) >> 6;
 288
 289     //printf("minx = %d, maxx = %d, miny = %d, maxy = %d\n", minx, maxx, miny, maxy);
 290
 291     unsigned char *bits;
 292
 293     raster->flow   = TT_Flow_Down;
 294     raster->width  = maxx - minx;
 295     raster->rows   = maxy - miny;
 296     raster->cols   = (raster->width + 7) / 8;
 297     raster->size   = raster->cols * raster->rows;
 298
 299     raster->bitmap = bits = LE_NEW_ARRAY(unsigned char, raster->size);
 300
 301     for (i = 0; i < raster->size; i += 1) {
 302         bits[i] = 0;
 303     }
 304
 305     xx = (-minx) * 64; yy = (-miny) * 64;
 306
 307     for (i = 0; i < glyphCount; i += 1) {
 308         if (glyphs[i] < 0xFFFE) {
 309             error = TT_Load_Glyph(fInstance, fGlyph, (TT_UShort) LE_GET_GLYPH(glyphs[i]), TTLOAD_SCALE_GLYPH | TTLOAD_HINT_GLYPH);
 310
 311             if (error == 0) {
 312                 TT_Get_Glyph_Bitmap(fGlyph, raster, xx, yy + (dy[i] * 64));
 313             }
 314         }
 315
 316         xx += (dx[i] * 64);
 317     }
 318
 319     for (i = 0; i < raster->size; i += 1) {
 320         bits[i] = bitReverse[bits[i]];
 321     }
 322
 323     xOffset = minx;
 324     yOffset = maxy;
 325
 326     return raster;
 327 }
 328
 329 void GnomeFontInstance::freeRaster(TT_Raster_Map *raster)
 330 {
 331     LE_DELETE_ARRAY(raster->bitmap);
 332     delete raster;
 333 }