1 /***************************************************************************/ 2 /* */ 3 /* ftimage.h */ 4 /* */ 5 /* FreeType glyph image formats and default raster interface */ 6 /* (specification). */ 7 /* */ 8 /* Copyright 1996-2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009, */ 9 /* 2010 by */ 10 /* David Turner, Robert Wilhelm, and Werner Lemberg. */ 11 /* */ 12 /* This file is part of the FreeType project, and may only be used, */ 13 /* modified, and distributed under the terms of the FreeType project */ 14 /* license, LICENSE.TXT. By continuing to use, modify, or distribute */ 15 /* this file you indicate that you have read the license and */ 16 /* understand and accept it fully. */ 17 /* */ 18 /***************************************************************************/ 19 20 /*************************************************************************/ 21 /* */ 22 /* Note: A `raster' is simply a scan-line converter, used to render */ 23 /* FT_Outlines into FT_Bitmaps. */ 24 /* */ 25 /*************************************************************************/ 26 27 28 #ifndef __FTIMAGE_H__ 29 #define __FTIMAGE_H__ 30 31 32 /* _STANDALONE_ is from ftgrays.c */ 33 #ifndef _STANDALONE_ 34 #include <ft2build.h> 35 #endif 36 37 38 FT_BEGIN_HEADER 39 40 41 /*************************************************************************/ 42 /* */ 43 /* <Section> */ 44 /* basic_types */ 45 /* */ 46 /*************************************************************************/ 47 48 49 /*************************************************************************/ 50 /* */ 51 /* <Type> */ 52 /* FT_Pos */ 53 /* */ 54 /* <Description> */ 55 /* The type FT_Pos is used to store vectorial coordinates. Depending */ 56 /* on the context, these can represent distances in integer font */ 57 /* units, or 16.16, or 26.6 fixed float pixel coordinates. */ 58 /* */ 59 typedef signed long FT_Pos; 60 61 62 /*************************************************************************/ 63 /* */ 64 /* <Struct> */ 65 /* FT_Vector */ 66 /* */ 67 /* <Description> */ 68 /* A simple structure used to store a 2D vector; coordinates are of */ 69 /* the FT_Pos type. */ 70 /* */ 71 /* <Fields> */ 72 /* x :: The horizontal coordinate. */ 73 /* y :: The vertical coordinate. */ 74 /* */ 75 typedef struct FT_Vector_ 76 { 77 FT_Pos x; 78 FT_Pos y; 79 80 } FT_Vector; 81 82 83 /*************************************************************************/ 84 /* */ 85 /* <Struct> */ 86 /* FT_BBox */ 87 /* */ 88 /* <Description> */ 89 /* A structure used to hold an outline's bounding box, i.e., the */ 90 /* coordinates of its extrema in the horizontal and vertical */ 91 /* directions. */ 92 /* */ 93 /* <Fields> */ 94 /* xMin :: The horizontal minimum (left-most). */ 95 /* */ 96 /* yMin :: The vertical minimum (bottom-most). */ 97 /* */ 98 /* xMax :: The horizontal maximum (right-most). */ 99 /* */ 100 /* yMax :: The vertical maximum (top-most). */ 101 /* */ 102 /* <Note> */ 103 /* The bounding box is specified with the coordinates of the lower */ 104 /* left and the upper right corner. In PostScript, those values are */ 105 /* often called (llx,lly) and (urx,ury), respectively. */ 106 /* */ 107 /* If `yMin' is negative, this value gives the glyph's descender. */ 108 /* Otherwise, the glyph doesn't descend below the baseline. */ 109 /* Similarly, if `ymax' is positive, this value gives the glyph's */ 110 /* ascender. */ 111 /* */ 112 /* `xMin' gives the horizontal distance from the glyph's origin to */ 113 /* the left edge of the glyph's bounding box. If `xMin' is negative, */ 114 /* the glyph extends to the left of the origin. */ 115 /* */ 116 typedef struct FT_BBox_ 117 { 118 FT_Pos xMin, yMin; 119 FT_Pos xMax, yMax; 120 121 } FT_BBox; 122 123 124 /*************************************************************************/ 125 /* */ 126 /* <Enum> */ 127 /* FT_Pixel_Mode */ 128 /* */ 129 /* <Description> */ 130 /* An enumeration type used to describe the format of pixels in a */ 131 /* given bitmap. Note that additional formats may be added in the */ 132 /* future. */ 133 /* */ 134 /* <Values> */ 135 /* FT_PIXEL_MODE_NONE :: */ 136 /* Value~0 is reserved. */ 137 /* */ 138 /* FT_PIXEL_MODE_MONO :: */ 139 /* A monochrome bitmap, using 1~bit per pixel. Note that pixels */ 140 /* are stored in most-significant order (MSB), which means that */ 141 /* the left-most pixel in a byte has value 128. */ 142 /* */ 143 /* FT_PIXEL_MODE_GRAY :: */ 144 /* An 8-bit bitmap, generally used to represent anti-aliased glyph */ 145 /* images. Each pixel is stored in one byte. Note that the number */ 146 /* of `gray' levels is stored in the `num_grays' field of the */ 147 /* @FT_Bitmap structure (it generally is 256). */ 148 /* */ 149 /* FT_PIXEL_MODE_GRAY2 :: */ 150 /* A 2-bit per pixel bitmap, used to represent embedded */ 151 /* anti-aliased bitmaps in font files according to the OpenType */ 152 /* specification. We haven't found a single font using this */ 153 /* format, however. */ 154 /* */ 155 /* FT_PIXEL_MODE_GRAY4 :: */ 156 /* A 4-bit per pixel bitmap, representing embedded anti-aliased */ 157 /* bitmaps in font files according to the OpenType specification. */ 158 /* We haven't found a single font using this format, however. */ 159 /* */ 160 /* FT_PIXEL_MODE_LCD :: */ 161 /* An 8-bit bitmap, representing RGB or BGR decimated glyph images */ 162 /* used for display on LCD displays; the bitmap is three times */ 163 /* wider than the original glyph image. See also */ 164 /* @FT_RENDER_MODE_LCD. */ 165 /* */ 166 /* FT_PIXEL_MODE_LCD_V :: */ 167 /* An 8-bit bitmap, representing RGB or BGR decimated glyph images */ 168 /* used for display on rotated LCD displays; the bitmap is three */ 169 /* times taller than the original glyph image. See also */ 170 /* @FT_RENDER_MODE_LCD_V. */ 171 /* */ 172 typedef enum FT_Pixel_Mode_ 173 { 174 FT_PIXEL_MODE_NONE = 0, 175 FT_PIXEL_MODE_MONO, 176 FT_PIXEL_MODE_GRAY, 177 FT_PIXEL_MODE_GRAY2, 178 FT_PIXEL_MODE_GRAY4, 179 FT_PIXEL_MODE_LCD, 180 FT_PIXEL_MODE_LCD_V, 181 182 FT_PIXEL_MODE_MAX /* do not remove */ 183 184 } FT_Pixel_Mode; 185 186 187 /*************************************************************************/ 188 /* */ 189 /* <Enum> */ 190 /* ft_pixel_mode_xxx */ 191 /* */ 192 /* <Description> */ 193 /* A list of deprecated constants. Use the corresponding */ 194 /* @FT_Pixel_Mode values instead. */ 195 /* */ 196 /* <Values> */ 197 /* ft_pixel_mode_none :: See @FT_PIXEL_MODE_NONE. */ 198 /* ft_pixel_mode_mono :: See @FT_PIXEL_MODE_MONO. */ 199 /* ft_pixel_mode_grays :: See @FT_PIXEL_MODE_GRAY. */ 200 /* ft_pixel_mode_pal2 :: See @FT_PIXEL_MODE_GRAY2. */ 201 /* ft_pixel_mode_pal4 :: See @FT_PIXEL_MODE_GRAY4. */ 202 /* */ 203 #define ft_pixel_mode_none FT_PIXEL_MODE_NONE 204 #define ft_pixel_mode_mono FT_PIXEL_MODE_MONO 205 #define ft_pixel_mode_grays FT_PIXEL_MODE_GRAY 206 #define ft_pixel_mode_pal2 FT_PIXEL_MODE_GRAY2 207 #define ft_pixel_mode_pal4 FT_PIXEL_MODE_GRAY4 208 209 /* */ 210 211 #if 0 212 213 /*************************************************************************/ 214 /* */ 215 /* <Enum> */ 216 /* FT_Palette_Mode */ 217 /* */ 218 /* <Description> */ 219 /* THIS TYPE IS DEPRECATED. DO NOT USE IT! */ 220 /* */ 221 /* An enumeration type to describe the format of a bitmap palette, */ 222 /* used with ft_pixel_mode_pal4 and ft_pixel_mode_pal8. */ 223 /* */ 224 /* <Values> */ 225 /* ft_palette_mode_rgb :: The palette is an array of 3-byte RGB */ 226 /* records. */ 227 /* */ 228 /* ft_palette_mode_rgba :: The palette is an array of 4-byte RGBA */ 229 /* records. */ 230 /* */ 231 /* <Note> */ 232 /* As ft_pixel_mode_pal2, pal4 and pal8 are currently unused by */ 233 /* FreeType, these types are not handled by the library itself. */ 234 /* */ 235 typedef enum FT_Palette_Mode_ 236 { 237 ft_palette_mode_rgb = 0, 238 ft_palette_mode_rgba, 239 240 ft_palette_mode_max /* do not remove */ 241 242 } FT_Palette_Mode; 243 244 /* */ 245 246 #endif 247 248 249 /*************************************************************************/ 250 /* */ 251 /* <Struct> */ 252 /* FT_Bitmap */ 253 /* */ 254 /* <Description> */ 255 /* A structure used to describe a bitmap or pixmap to the raster. */ 256 /* Note that we now manage pixmaps of various depths through the */ 257 /* `pixel_mode' field. */ 258 /* */ 259 /* <Fields> */ 260 /* rows :: The number of bitmap rows. */ 261 /* */ 262 /* width :: The number of pixels in bitmap row. */ 263 /* */ 264 /* pitch :: The pitch's absolute value is the number of bytes */ 265 /* taken by one bitmap row, including padding. */ 266 /* However, the pitch is positive when the bitmap has */ 267 /* a `down' flow, and negative when it has an `up' */ 268 /* flow. In all cases, the pitch is an offset to add */ 269 /* to a bitmap pointer in order to go down one row. */ 270 /* */ 271 /* Note that `padding' means the alignment of a */ 272 /* bitmap to a byte border, and FreeType functions */ 273 /* normally align to the smallest possible integer */ 274 /* value. */ 275 /* */ 276 /* For the B/W rasterizer, `pitch' is always an even */ 277 /* number. */ 278 /* */ 279 /* To change the pitch of a bitmap (say, to make it a */ 280 /* multiple of 4), use @FT_Bitmap_Convert. */ 281 /* Alternatively, you might use callback functions to */ 282 /* directly render to the application's surface; see */ 283 /* the file `example2.cpp' in the tutorial for a */ 284 /* demonstration. */ 285 /* */ 286 /* buffer :: A typeless pointer to the bitmap buffer. This */ 287 /* value should be aligned on 32-bit boundaries in */ 288 /* most cases. */ 289 /* */ 290 /* num_grays :: This field is only used with */ 291 /* @FT_PIXEL_MODE_GRAY; it gives the number of gray */ 292 /* levels used in the bitmap. */ 293 /* */ 294 /* pixel_mode :: The pixel mode, i.e., how pixel bits are stored. */ 295 /* See @FT_Pixel_Mode for possible values. */ 296 /* */ 297 /* palette_mode :: This field is intended for paletted pixel modes; */ 298 /* it indicates how the palette is stored. Not */ 299 /* used currently. */ 300 /* */ 301 /* palette :: A typeless pointer to the bitmap palette; this */ 302 /* field is intended for paletted pixel modes. Not */ 303 /* used currently. */ 304 /* */ 305 /* <Note> */ 306 /* For now, the only pixel modes supported by FreeType are mono and */ 307 /* grays. However, drivers might be added in the future to support */ 308 /* more `colorful' options. */ 309 /* */ 310 typedef struct FT_Bitmap_ 311 { 312 int rows; 313 int width; 314 int pitch; 315 unsigned char* buffer; 316 short num_grays; 317 char pixel_mode; 318 char palette_mode; 319 void* palette; 320 321 } FT_Bitmap; 322 323 324 /*************************************************************************/ 325 /* */ 326 /* <Section> */ 327 /* outline_processing */ 328 /* */ 329 /*************************************************************************/ 330 331 332 /*************************************************************************/ 333 /* */ 334 /* <Struct> */ 335 /* FT_Outline */ 336 /* */ 337 /* <Description> */ 338 /* This structure is used to describe an outline to the scan-line */ 339 /* converter. */ 340 /* */ 341 /* <Fields> */ 342 /* n_contours :: The number of contours in the outline. */ 343 /* */ 344 /* n_points :: The number of points in the outline. */ 345 /* */ 346 /* points :: A pointer to an array of `n_points' @FT_Vector */ 347 /* elements, giving the outline's point coordinates. */ 348 /* */ 349 /* tags :: A pointer to an array of `n_points' chars, giving */ 350 /* each outline point's type. */ 351 /* */ 352 /* If bit~0 is unset, the point is `off' the curve, */ 353 /* i.e., a Bzier control point, while it is `on' if */ 354 /* set. */ 355 /* */ 356 /* Bit~1 is meaningful for `off' points only. If set, */ 357 /* it indicates a third-order Bzier arc control point; */ 358 /* and a second-order control point if unset. */ 359 /* */ 360 /* If bit~2 is set, bits 5-7 contain the drop-out mode */ 361 /* (as defined in the OpenType specification; the value */ 362 /* is the same as the argument to the SCANMODE */ 363 /* instruction). */ 364 /* */ 365 /* Bits 3 and~4 are reserved for internal purposes. */ 366 /* */ 367 /* contours :: An array of `n_contours' shorts, giving the end */ 368 /* point of each contour within the outline. For */ 369 /* example, the first contour is defined by the points */ 370 /* `0' to `contours[0]', the second one is defined by */ 371 /* the points `contours[0]+1' to `contours[1]', etc. */ 372 /* */ 373 /* flags :: A set of bit flags used to characterize the outline */ 374 /* and give hints to the scan-converter and hinter on */ 375 /* how to convert/grid-fit it. See @FT_OUTLINE_FLAGS. */ 376 /* */ 377 /* <Note> */ 378 /* The B/W rasterizer only checks bit~2 in the `tags' array for the */ 379 /* first point of each contour. The drop-out mode as given with */ 380 /* @FT_OUTLINE_IGNORE_DROPOUTS, @FT_OUTLINE_SMART_DROPOUTS, and */ 381 /* @FT_OUTLINE_INCLUDE_STUBS in `flags' is then overridden. */ 382 /* */ 383 typedef struct FT_Outline_ 384 { 385 short n_contours; /* number of contours in glyph */ 386 short n_points; /* number of points in the glyph */ 387 388 FT_Vector* points; /* the outline's points */ 389 char* tags; /* the points flags */ 390 short* contours; /* the contour end points */ 391 392 int flags; /* outline masks */ 393 394 } FT_Outline; 395 396 /* Following limits must be consistent with */ 397 /* FT_Outline.{n_contours,n_points} */ 398 #define FT_OUTLINE_CONTOURS_MAX SHRT_MAX 399 #define FT_OUTLINE_POINTS_MAX SHRT_MAX 400 401 402 /*************************************************************************/ 403 /* */ 404 /* <Enum> */ 405 /* FT_OUTLINE_FLAGS */ 406 /* */ 407 /* <Description> */ 408 /* A list of bit-field constants use for the flags in an outline's */ 409 /* `flags' field. */ 410 /* */ 411 /* <Values> */ 412 /* FT_OUTLINE_NONE :: */ 413 /* Value~0 is reserved. */ 414 /* */ 415 /* FT_OUTLINE_OWNER :: */ 416 /* If set, this flag indicates that the outline's field arrays */ 417 /* (i.e., `points', `flags', and `contours') are `owned' by the */ 418 /* outline object, and should thus be freed when it is destroyed. */ 419 /* */ 420 /* FT_OUTLINE_EVEN_ODD_FILL :: */ 421 /* By default, outlines are filled using the non-zero winding rule. */ 422 /* If set to 1, the outline will be filled using the even-odd fill */ 423 /* rule (only works with the smooth rasterizer). */ 424 /* */ 425 /* FT_OUTLINE_REVERSE_FILL :: */ 426 /* By default, outside contours of an outline are oriented in */ 427 /* clock-wise direction, as defined in the TrueType specification. */ 428 /* This flag is set if the outline uses the opposite direction */ 429 /* (typically for Type~1 fonts). This flag is ignored by the scan */ 430 /* converter. */ 431 /* */ 432 /* FT_OUTLINE_IGNORE_DROPOUTS :: */ 433 /* By default, the scan converter will try to detect drop-outs in */ 434 /* an outline and correct the glyph bitmap to ensure consistent */ 435 /* shape continuity. If set, this flag hints the scan-line */ 436 /* converter to ignore such cases. See below for more information. */ 437 /* */ 438 /* FT_OUTLINE_SMART_DROPOUTS :: */ 439 /* Select smart dropout control. If unset, use simple dropout */ 440 /* control. Ignored if @FT_OUTLINE_IGNORE_DROPOUTS is set. See */ 441 /* below for more information. */ 442 /* */ 443 /* FT_OUTLINE_INCLUDE_STUBS :: */ 444 /* If set, turn pixels on for `stubs', otherwise exclude them. */ 445 /* Ignored if @FT_OUTLINE_IGNORE_DROPOUTS is set. See below for */ 446 /* more information. */ 447 /* */ 448 /* FT_OUTLINE_HIGH_PRECISION :: */ 449 /* This flag indicates that the scan-line converter should try to */ 450 /* convert this outline to bitmaps with the highest possible */ 451 /* quality. It is typically set for small character sizes. Note */ 452 /* that this is only a hint that might be completely ignored by a */ 453 /* given scan-converter. */ 454 /* */ 455 /* FT_OUTLINE_SINGLE_PASS :: */ 456 /* This flag is set to force a given scan-converter to only use a */ 457 /* single pass over the outline to render a bitmap glyph image. */ 458 /* Normally, it is set for very large character sizes. It is only */ 459 /* a hint that might be completely ignored by a given */ 460 /* scan-converter. */ 461 /* */ 462 /* <Note> */ 463 /* The flags @FT_OUTLINE_IGNORE_DROPOUTS, @FT_OUTLINE_SMART_DROPOUTS, */ 464 /* and @FT_OUTLINE_INCLUDE_STUBS are ignored by the smooth */ 465 /* rasterizer. */ 466 /* */ 467 /* There exists a second mechanism to pass the drop-out mode to the */ 468 /* B/W rasterizer; see the `tags' field in @FT_Outline. */ 469 /* */ 470 /* Please refer to the description of the `SCANTYPE' instruction in */ 471 /* the OpenType specification (in file `ttinst1.doc') how simple */ 472 /* drop-outs, smart drop-outs, and stubs are defined. */ 473 /* */ 474 #define FT_OUTLINE_NONE 0x0 475 #define FT_OUTLINE_OWNER 0x1 476 #define FT_OUTLINE_EVEN_ODD_FILL 0x2 477 #define FT_OUTLINE_REVERSE_FILL 0x4 478 #define FT_OUTLINE_IGNORE_DROPOUTS 0x8 479 #define FT_OUTLINE_SMART_DROPOUTS 0x10 480 #define FT_OUTLINE_INCLUDE_STUBS 0x20 481 482 #define FT_OUTLINE_HIGH_PRECISION 0x100 483 #define FT_OUTLINE_SINGLE_PASS 0x200 484 485 486 /************************************************************************* 487 * 488 * @enum: 489 * ft_outline_flags 490 * 491 * @description: 492 * These constants are deprecated. Please use the corresponding 493 * @FT_OUTLINE_FLAGS values. 494 * 495 * @values: 496 * ft_outline_none :: See @FT_OUTLINE_NONE. 497 * ft_outline_owner :: See @FT_OUTLINE_OWNER. 498 * ft_outline_even_odd_fill :: See @FT_OUTLINE_EVEN_ODD_FILL. 499 * ft_outline_reverse_fill :: See @FT_OUTLINE_REVERSE_FILL. 500 * ft_outline_ignore_dropouts :: See @FT_OUTLINE_IGNORE_DROPOUTS. 501 * ft_outline_high_precision :: See @FT_OUTLINE_HIGH_PRECISION. 502 * ft_outline_single_pass :: See @FT_OUTLINE_SINGLE_PASS. 503 */ 504 #define ft_outline_none FT_OUTLINE_NONE 505 #define ft_outline_owner FT_OUTLINE_OWNER 506 #define ft_outline_even_odd_fill FT_OUTLINE_EVEN_ODD_FILL 507 #define ft_outline_reverse_fill FT_OUTLINE_REVERSE_FILL 508 #define ft_outline_ignore_dropouts FT_OUTLINE_IGNORE_DROPOUTS 509 #define ft_outline_high_precision FT_OUTLINE_HIGH_PRECISION 510 #define ft_outline_single_pass FT_OUTLINE_SINGLE_PASS 511 512 /* */ 513 514 #define FT_CURVE_TAG( flag ) ( flag & 3 ) 515 516 #define FT_CURVE_TAG_ON 1 517 #define FT_CURVE_TAG_CONIC 0 518 #define FT_CURVE_TAG_CUBIC 2 519 520 #define FT_CURVE_TAG_HAS_SCANMODE 4 521 522 #define FT_CURVE_TAG_TOUCH_X 8 /* reserved for the TrueType hinter */ 523 #define FT_CURVE_TAG_TOUCH_Y 16 /* reserved for the TrueType hinter */ 524 525 #define FT_CURVE_TAG_TOUCH_BOTH ( FT_CURVE_TAG_TOUCH_X | \ 526 FT_CURVE_TAG_TOUCH_Y ) 527 528 #define FT_Curve_Tag_On FT_CURVE_TAG_ON 529 #define FT_Curve_Tag_Conic FT_CURVE_TAG_CONIC 530 #define FT_Curve_Tag_Cubic FT_CURVE_TAG_CUBIC 531 #define FT_Curve_Tag_Touch_X FT_CURVE_TAG_TOUCH_X 532 #define FT_Curve_Tag_Touch_Y FT_CURVE_TAG_TOUCH_Y 533 534 535 /*************************************************************************/ 536 /* */ 537 /* <FuncType> */ 538 /* FT_Outline_MoveToFunc */ 539 /* */ 540 /* <Description> */ 541 /* A function pointer type used to describe the signature of a `move */ 542 /* to' function during outline walking/decomposition. */ 543 /* */ 544 /* A `move to' is emitted to start a new contour in an outline. */ 545 /* */ 546 /* <Input> */ 547 /* to :: A pointer to the target point of the `move to'. */ 548 /* */ 549 /* user :: A typeless pointer which is passed from the caller of the */ 550 /* decomposition function. */ 551 /* */ 552 /* <Return> */ 553 /* Error code. 0~means success. */ 554 /* */ 555 typedef int 556 (*FT_Outline_MoveToFunc)( const FT_Vector* to, 557 void* user ); 558 559 #define FT_Outline_MoveTo_Func FT_Outline_MoveToFunc 560 561 562 /*************************************************************************/ 563 /* */ 564 /* <FuncType> */ 565 /* FT_Outline_LineToFunc */ 566 /* */ 567 /* <Description> */ 568 /* A function pointer type used to describe the signature of a `line */ 569 /* to' function during outline walking/decomposition. */ 570 /* */ 571 /* A `line to' is emitted to indicate a segment in the outline. */ 572 /* */ 573 /* <Input> */ 574 /* to :: A pointer to the target point of the `line to'. */ 575 /* */ 576 /* user :: A typeless pointer which is passed from the caller of the */ 577 /* decomposition function. */ 578 /* */ 579 /* <Return> */ 580 /* Error code. 0~means success. */ 581 /* */ 582 typedef int 583 (*FT_Outline_LineToFunc)( const FT_Vector* to, 584 void* user ); 585 586 #define FT_Outline_LineTo_Func FT_Outline_LineToFunc 587 588 589 /*************************************************************************/ 590 /* */ 591 /* <FuncType> */ 592 /* FT_Outline_ConicToFunc */ 593 /* */ 594 /* <Description> */ 595 /* A function pointer type used to describe the signature of a `conic */ 596 /* to' function during outline walking or decomposition. */ 597 /* */ 598 /* A `conic to' is emitted to indicate a second-order Bzier arc in */ 599 /* the outline. */ 600 /* */ 601 /* <Input> */ 602 /* control :: An intermediate control point between the last position */ 603 /* and the new target in `to'. */ 604 /* */ 605 /* to :: A pointer to the target end point of the conic arc. */ 606 /* */ 607 /* user :: A typeless pointer which is passed from the caller of */ 608 /* the decomposition function. */ 609 /* */ 610 /* <Return> */ 611 /* Error code. 0~means success. */ 612 /* */ 613 typedef int 614 (*FT_Outline_ConicToFunc)( const FT_Vector* control, 615 const FT_Vector* to, 616 void* user ); 617 618 #define FT_Outline_ConicTo_Func FT_Outline_ConicToFunc 619 620 621 /*************************************************************************/ 622 /* */ 623 /* <FuncType> */ 624 /* FT_Outline_CubicToFunc */ 625 /* */ 626 /* <Description> */ 627 /* A function pointer type used to describe the signature of a `cubic */ 628 /* to' function during outline walking or decomposition. */ 629 /* */ 630 /* A `cubic to' is emitted to indicate a third-order Bzier arc. */ 631 /* */ 632 /* <Input> */ 633 /* control1 :: A pointer to the first Bzier control point. */ 634 /* */ 635 /* control2 :: A pointer to the second Bzier control point. */ 636 /* */ 637 /* to :: A pointer to the target end point. */ 638 /* */ 639 /* user :: A typeless pointer which is passed from the caller of */ 640 /* the decomposition function. */ 641 /* */ 642 /* <Return> */ 643 /* Error code. 0~means success. */ 644 /* */ 645 typedef int 646 (*FT_Outline_CubicToFunc)( const FT_Vector* control1, 647 const FT_Vector* control2, 648 const FT_Vector* to, 649 void* user ); 650 651 #define FT_Outline_CubicTo_Func FT_Outline_CubicToFunc 652 653 654 /*************************************************************************/ 655 /* */ 656 /* <Struct> */ 657 /* FT_Outline_Funcs */ 658 /* */ 659 /* <Description> */ 660 /* A structure to hold various function pointers used during outline */ 661 /* decomposition in order to emit segments, conic, and cubic Bziers. */ 662 /* */ 663 /* <Fields> */ 664 /* move_to :: The `move to' emitter. */ 665 /* */ 666 /* line_to :: The segment emitter. */ 667 /* */ 668 /* conic_to :: The second-order Bzier arc emitter. */ 669 /* */ 670 /* cubic_to :: The third-order Bzier arc emitter. */ 671 /* */ 672 /* shift :: The shift that is applied to coordinates before they */ 673 /* are sent to the emitter. */ 674 /* */ 675 /* delta :: The delta that is applied to coordinates before they */ 676 /* are sent to the emitter, but after the shift. */ 677 /* */ 678 /* <Note> */ 679 /* The point coordinates sent to the emitters are the transformed */ 680 /* version of the original coordinates (this is important for high */ 681 /* accuracy during scan-conversion). The transformation is simple: */ 682 /* */ 683 /* { */ 684 /* x' = (x << shift) - delta */ 685 /* y' = (x << shift) - delta */ 686 /* } */ 687 /* */ 688 /* Set the values of `shift' and `delta' to~0 to get the original */ 689 /* point coordinates. */ 690 /* */ 691 typedef struct FT_Outline_Funcs_ 692 { 693 FT_Outline_MoveToFunc move_to; 694 FT_Outline_LineToFunc line_to; 695 FT_Outline_ConicToFunc conic_to; 696 FT_Outline_CubicToFunc cubic_to; 697 698 int shift; 699 FT_Pos delta; 700 701 } FT_Outline_Funcs; 702 703 704 /*************************************************************************/ 705 /* */ 706 /* <Section> */ 707 /* basic_types */ 708 /* */ 709 /*************************************************************************/ 710 711 712 /*************************************************************************/ 713 /* */ 714 /* <Macro> */ 715 /* FT_IMAGE_TAG */ 716 /* */ 717 /* <Description> */ 718 /* This macro converts four-letter tags to an unsigned long type. */ 719 /* */ 720 /* <Note> */ 721 /* Since many 16-bit compilers don't like 32-bit enumerations, you */ 722 /* should redefine this macro in case of problems to something like */ 723 /* this: */ 724 /* */ 725 /* { */ 726 /* #define FT_IMAGE_TAG( value, _x1, _x2, _x3, _x4 ) value */ 727 /* } */ 728 /* */ 729 /* to get a simple enumeration without assigning special numbers. */ 730 /* */ 731 #ifndef FT_IMAGE_TAG 732 #define FT_IMAGE_TAG( value, _x1, _x2, _x3, _x4 ) \ 733 value = ( ( (unsigned long)_x1 << 24 ) | \ 734 ( (unsigned long)_x2 << 16 ) | \ 735 ( (unsigned long)_x3 << 8 ) | \ 736 (unsigned long)_x4 ) 737 #endif /* FT_IMAGE_TAG */ 738 739 740 /*************************************************************************/ 741 /* */ 742 /* <Enum> */ 743 /* FT_Glyph_Format */ 744 /* */ 745 /* <Description> */ 746 /* An enumeration type used to describe the format of a given glyph */ 747 /* image. Note that this version of FreeType only supports two image */ 748 /* formats, even though future font drivers will be able to register */ 749 /* their own format. */ 750 /* */ 751 /* <Values> */ 752 /* FT_GLYPH_FORMAT_NONE :: */ 753 /* The value~0 is reserved. */ 754 /* */ 755 /* FT_GLYPH_FORMAT_COMPOSITE :: */ 756 /* The glyph image is a composite of several other images. This */ 757 /* format is _only_ used with @FT_LOAD_NO_RECURSE, and is used to */ 758 /* report compound glyphs (like accented characters). */ 759 /* */ 760 /* FT_GLYPH_FORMAT_BITMAP :: */ 761 /* The glyph image is a bitmap, and can be described as an */ 762 /* @FT_Bitmap. You generally need to access the `bitmap' field of */ 763 /* the @FT_GlyphSlotRec structure to read it. */ 764 /* */ 765 /* FT_GLYPH_FORMAT_OUTLINE :: */ 766 /* The glyph image is a vectorial outline made of line segments */ 767 /* and Bzier arcs; it can be described as an @FT_Outline; you */ 768 /* generally want to access the `outline' field of the */ 769 /* @FT_GlyphSlotRec structure to read it. */ 770 /* */ 771 /* FT_GLYPH_FORMAT_PLOTTER :: */ 772 /* The glyph image is a vectorial path with no inside and outside */ 773 /* contours. Some Type~1 fonts, like those in the Hershey family, */ 774 /* contain glyphs in this format. These are described as */ 775 /* @FT_Outline, but FreeType isn't currently capable of rendering */ 776 /* them correctly. */ 777 /* */ 778 typedef enum FT_Glyph_Format_ 779 { 780 FT_IMAGE_TAG( FT_GLYPH_FORMAT_NONE, 0, 0, 0, 0 ), 781 782 FT_IMAGE_TAG( FT_GLYPH_FORMAT_COMPOSITE, 'c', 'o', 'm', 'p' ), 783 FT_IMAGE_TAG( FT_GLYPH_FORMAT_BITMAP, 'b', 'i', 't', 's' ), 784 FT_IMAGE_TAG( FT_GLYPH_FORMAT_OUTLINE, 'o', 'u', 't', 'l' ), 785 FT_IMAGE_TAG( FT_GLYPH_FORMAT_PLOTTER, 'p', 'l', 'o', 't' ) 786 787 } FT_Glyph_Format; 788 789 790 /*************************************************************************/ 791 /* */ 792 /* <Enum> */ 793 /* ft_glyph_format_xxx */ 794 /* */ 795 /* <Description> */ 796 /* A list of deprecated constants. Use the corresponding */ 797 /* @FT_Glyph_Format values instead. */ 798 /* */ 799 /* <Values> */ 800 /* ft_glyph_format_none :: See @FT_GLYPH_FORMAT_NONE. */ 801 /* ft_glyph_format_composite :: See @FT_GLYPH_FORMAT_COMPOSITE. */ 802 /* ft_glyph_format_bitmap :: See @FT_GLYPH_FORMAT_BITMAP. */ 803 /* ft_glyph_format_outline :: See @FT_GLYPH_FORMAT_OUTLINE. */ 804 /* ft_glyph_format_plotter :: See @FT_GLYPH_FORMAT_PLOTTER. */ 805 /* */ 806 #define ft_glyph_format_none FT_GLYPH_FORMAT_NONE 807 #define ft_glyph_format_composite FT_GLYPH_FORMAT_COMPOSITE 808 #define ft_glyph_format_bitmap FT_GLYPH_FORMAT_BITMAP 809 #define ft_glyph_format_outline FT_GLYPH_FORMAT_OUTLINE 810 #define ft_glyph_format_plotter FT_GLYPH_FORMAT_PLOTTER 811 812 813 /*************************************************************************/ 814 /*************************************************************************/ 815 /*************************************************************************/ 816 /***** *****/ 817 /***** R A S T E R D E F I N I T I O N S *****/ 818 /***** *****/ 819 /*************************************************************************/ 820 /*************************************************************************/ 821 /*************************************************************************/ 822 823 824 /*************************************************************************/ 825 /* */ 826 /* A raster is a scan converter, in charge of rendering an outline into */ 827 /* a a bitmap. This section contains the public API for rasters. */ 828 /* */ 829 /* Note that in FreeType 2, all rasters are now encapsulated within */ 830 /* specific modules called `renderers'. See `freetype/ftrender.h' for */ 831 /* more details on renderers. */ 832 /* */ 833 /*************************************************************************/ 834 835 836 /*************************************************************************/ 837 /* */ 838 /* <Section> */ 839 /* raster */ 840 /* */ 841 /* <Title> */ 842 /* Scanline Converter */ 843 /* */ 844 /* <Abstract> */ 845 /* How vectorial outlines are converted into bitmaps and pixmaps. */ 846 /* */ 847 /* <Description> */ 848 /* This section contains technical definitions. */ 849 /* */ 850 /*************************************************************************/ 851 852 853 /*************************************************************************/ 854 /* */ 855 /* <Type> */ 856 /* FT_Raster */ 857 /* */ 858 /* <Description> */ 859 /* A handle (pointer) to a raster object. Each object can be used */ 860 /* independently to convert an outline into a bitmap or pixmap. */ 861 /* */ 862 typedef struct FT_RasterRec_* FT_Raster; 863 864 865 /*************************************************************************/ 866 /* */ 867 /* <Struct> */ 868 /* FT_Span */ 869 /* */ 870 /* <Description> */ 871 /* A structure used to model a single span of gray (or black) pixels */ 872 /* when rendering a monochrome or anti-aliased bitmap. */ 873 /* */ 874 /* <Fields> */ 875 /* x :: The span's horizontal start position. */ 876 /* */ 877 /* len :: The span's length in pixels. */ 878 /* */ 879 /* coverage :: The span color/coverage, ranging from 0 (background) */ 880 /* to 255 (foreground). Only used for anti-aliased */ 881 /* rendering. */ 882 /* */ 883 /* <Note> */ 884 /* This structure is used by the span drawing callback type named */ 885 /* @FT_SpanFunc which takes the y~coordinate of the span as a */ 886 /* a parameter. */ 887 /* */ 888 /* The coverage value is always between 0 and 255. If you want less */ 889 /* gray values, the callback function has to reduce them. */ 890 /* */ 891 typedef struct FT_Span_ 892 { 893 short x; 894 unsigned short len; 895 unsigned char coverage; 896 897 } FT_Span; 898 899 900 /*************************************************************************/ 901 /* */ 902 /* <FuncType> */ 903 /* FT_SpanFunc */ 904 /* */ 905 /* <Description> */ 906 /* A function used as a call-back by the anti-aliased renderer in */ 907 /* order to let client applications draw themselves the gray pixel */ 908 /* spans on each scan line. */ 909 /* */ 910 /* <Input> */ 911 /* y :: The scanline's y~coordinate. */ 912 /* */ 913 /* count :: The number of spans to draw on this scanline. */ 914 /* */ 915 /* spans :: A table of `count' spans to draw on the scanline. */ 916 /* */ 917 /* user :: User-supplied data that is passed to the callback. */ 918 /* */ 919 /* <Note> */ 920 /* This callback allows client applications to directly render the */ 921 /* gray spans of the anti-aliased bitmap to any kind of surfaces. */ 922 /* */ 923 /* This can be used to write anti-aliased outlines directly to a */ 924 /* given background bitmap, and even perform translucency. */ 925 /* */ 926 /* Note that the `count' field cannot be greater than a fixed value */ 927 /* defined by the `FT_MAX_GRAY_SPANS' configuration macro in */ 928 /* `ftoption.h'. By default, this value is set to~32, which means */ 929 /* that if there are more than 32~spans on a given scanline, the */ 930 /* callback is called several times with the same `y' parameter in */ 931 /* order to draw all callbacks. */ 932 /* */ 933 /* Otherwise, the callback is only called once per scan-line, and */ 934 /* only for those scanlines that do have `gray' pixels on them. */ 935 /* */ 936 typedef void 937 (*FT_SpanFunc)( int y, 938 int count, 939 const FT_Span* spans, 940 void* user ); 941 942 #define FT_Raster_Span_Func FT_SpanFunc 943 944 945 /*************************************************************************/ 946 /* */ 947 /* <FuncType> */ 948 /* FT_Raster_BitTest_Func */ 949 /* */ 950 /* <Description> */ 951 /* THIS TYPE IS DEPRECATED. DO NOT USE IT. */ 952 /* */ 953 /* A function used as a call-back by the monochrome scan-converter */ 954 /* to test whether a given target pixel is already set to the drawing */ 955 /* `color'. These tests are crucial to implement drop-out control */ 956 /* per-se the TrueType spec. */ 957 /* */ 958 /* <Input> */ 959 /* y :: The pixel's y~coordinate. */ 960 /* */ 961 /* x :: The pixel's x~coordinate. */ 962 /* */ 963 /* user :: User-supplied data that is passed to the callback. */ 964 /* */ 965 /* <Return> */ 966 /* 1~if the pixel is `set', 0~otherwise. */ 967 /* */ 968 typedef int 969 (*FT_Raster_BitTest_Func)( int y, 970 int x, 971 void* user ); 972 973 974 /*************************************************************************/ 975 /* */ 976 /* <FuncType> */ 977 /* FT_Raster_BitSet_Func */ 978 /* */ 979 /* <Description> */ 980 /* THIS TYPE IS DEPRECATED. DO NOT USE IT. */ 981 /* */ 982 /* A function used as a call-back by the monochrome scan-converter */ 983 /* to set an individual target pixel. This is crucial to implement */ 984 /* drop-out control according to the TrueType specification. */ 985 /* */ 986 /* <Input> */ 987 /* y :: The pixel's y~coordinate. */ 988 /* */ 989 /* x :: The pixel's x~coordinate. */ 990 /* */ 991 /* user :: User-supplied data that is passed to the callback. */ 992 /* */ 993 /* <Return> */ 994 /* 1~if the pixel is `set', 0~otherwise. */ 995 /* */ 996 typedef void 997 (*FT_Raster_BitSet_Func)( int y, 998 int x, 999 void* user ); 1000 1001 1002 /*************************************************************************/ 1003 /* */ 1004 /* <Enum> */ 1005 /* FT_RASTER_FLAG_XXX */ 1006 /* */ 1007 /* <Description> */ 1008 /* A list of bit flag constants as used in the `flags' field of a */ 1009 /* @FT_Raster_Params structure. */ 1010 /* */ 1011 /* <Values> */ 1012 /* FT_RASTER_FLAG_DEFAULT :: This value is 0. */ 1013 /* */ 1014 /* FT_RASTER_FLAG_AA :: This flag is set to indicate that an */ 1015 /* anti-aliased glyph image should be */ 1016 /* generated. Otherwise, it will be */ 1017 /* monochrome (1-bit). */ 1018 /* */ 1019 /* FT_RASTER_FLAG_DIRECT :: This flag is set to indicate direct */ 1020 /* rendering. In this mode, client */ 1021 /* applications must provide their own span */ 1022 /* callback. This lets them directly */ 1023 /* draw or compose over an existing bitmap. */ 1024 /* If this bit is not set, the target */ 1025 /* pixmap's buffer _must_ be zeroed before */ 1026 /* rendering. */ 1027 /* */ 1028 /* Note that for now, direct rendering is */ 1029 /* only possible with anti-aliased glyphs. */ 1030 /* */ 1031 /* FT_RASTER_FLAG_CLIP :: This flag is only used in direct */ 1032 /* rendering mode. If set, the output will */ 1033 /* be clipped to a box specified in the */ 1034 /* `clip_box' field of the */ 1035 /* @FT_Raster_Params structure. */ 1036 /* */ 1037 /* Note that by default, the glyph bitmap */ 1038 /* is clipped to the target pixmap, except */ 1039 /* in direct rendering mode where all spans */ 1040 /* are generated if no clipping box is set. */ 1041 /* */ 1042 #define FT_RASTER_FLAG_DEFAULT 0x0 1043 #define FT_RASTER_FLAG_AA 0x1 1044 #define FT_RASTER_FLAG_DIRECT 0x2 1045 #define FT_RASTER_FLAG_CLIP 0x4 1046 1047 /* deprecated */ 1048 #define ft_raster_flag_default FT_RASTER_FLAG_DEFAULT 1049 #define ft_raster_flag_aa FT_RASTER_FLAG_AA 1050 #define ft_raster_flag_direct FT_RASTER_FLAG_DIRECT 1051 #define ft_raster_flag_clip FT_RASTER_FLAG_CLIP 1052 1053 1054 /*************************************************************************/ 1055 /* */ 1056 /* <Struct> */ 1057 /* FT_Raster_Params */ 1058 /* */ 1059 /* <Description> */ 1060 /* A structure to hold the arguments used by a raster's render */ 1061 /* function. */ 1062 /* */ 1063 /* <Fields> */ 1064 /* target :: The target bitmap. */ 1065 /* */ 1066 /* source :: A pointer to the source glyph image (e.g., an */ 1067 /* @FT_Outline). */ 1068 /* */ 1069 /* flags :: The rendering flags. */ 1070 /* */ 1071 /* gray_spans :: The gray span drawing callback. */ 1072 /* */ 1073 /* black_spans :: The black span drawing callback. UNIMPLEMENTED! */ 1074 /* */ 1075 /* bit_test :: The bit test callback. UNIMPLEMENTED! */ 1076 /* */ 1077 /* bit_set :: The bit set callback. UNIMPLEMENTED! */ 1078 /* */ 1079 /* user :: User-supplied data that is passed to each drawing */ 1080 /* callback. */ 1081 /* */ 1082 /* clip_box :: An optional clipping box. It is only used in */ 1083 /* direct rendering mode. Note that coordinates here */ 1084 /* should be expressed in _integer_ pixels (and not in */ 1085 /* 26.6 fixed-point units). */ 1086 /* */ 1087 /* <Note> */ 1088 /* An anti-aliased glyph bitmap is drawn if the @FT_RASTER_FLAG_AA */ 1089 /* bit flag is set in the `flags' field, otherwise a monochrome */ 1090 /* bitmap is generated. */ 1091 /* */ 1092 /* If the @FT_RASTER_FLAG_DIRECT bit flag is set in `flags', the */ 1093 /* raster will call the `gray_spans' callback to draw gray pixel */ 1094 /* spans, in the case of an aa glyph bitmap, it will call */ 1095 /* `black_spans', and `bit_test' and `bit_set' in the case of a */ 1096 /* monochrome bitmap. This allows direct composition over a */ 1097 /* pre-existing bitmap through user-provided callbacks to perform the */ 1098 /* span drawing/composition. */ 1099 /* */ 1100 /* Note that the `bit_test' and `bit_set' callbacks are required when */ 1101 /* rendering a monochrome bitmap, as they are crucial to implement */ 1102 /* correct drop-out control as defined in the TrueType specification. */ 1103 /* */ 1104 typedef struct FT_Raster_Params_ 1105 { 1106 const FT_Bitmap* target; 1107 const void* source; 1108 int flags; 1109 FT_SpanFunc gray_spans; 1110 FT_SpanFunc black_spans; /* doesn't work! */ 1111 FT_Raster_BitTest_Func bit_test; /* doesn't work! */ 1112 FT_Raster_BitSet_Func bit_set; /* doesn't work! */ 1113 void* user; 1114 FT_BBox clip_box; 1115 1116 } FT_Raster_Params; 1117 1118 1119 /*************************************************************************/ 1120 /* */ 1121 /* <FuncType> */ 1122 /* FT_Raster_NewFunc */ 1123 /* */ 1124 /* <Description> */ 1125 /* A function used to create a new raster object. */ 1126 /* */ 1127 /* <Input> */ 1128 /* memory :: A handle to the memory allocator. */ 1129 /* */ 1130 /* <Output> */ 1131 /* raster :: A handle to the new raster object. */ 1132 /* */ 1133 /* <Return> */ 1134 /* Error code. 0~means success. */ 1135 /* */ 1136 /* <Note> */ 1137 /* The `memory' parameter is a typeless pointer in order to avoid */ 1138 /* un-wanted dependencies on the rest of the FreeType code. In */ 1139 /* practice, it is an @FT_Memory object, i.e., a handle to the */ 1140 /* standard FreeType memory allocator. However, this field can be */ 1141 /* completely ignored by a given raster implementation. */ 1142 /* */ 1143 typedef int 1144 (*FT_Raster_NewFunc)( void* memory, 1145 FT_Raster* raster ); 1146 1147 #define FT_Raster_New_Func FT_Raster_NewFunc 1148 1149 1150 /*************************************************************************/ 1151 /* */ 1152 /* <FuncType> */ 1153 /* FT_Raster_DoneFunc */ 1154 /* */ 1155 /* <Description> */ 1156 /* A function used to destroy a given raster object. */ 1157 /* */ 1158 /* <Input> */ 1159 /* raster :: A handle to the raster object. */ 1160 /* */ 1161 typedef void 1162 (*FT_Raster_DoneFunc)( FT_Raster raster ); 1163 1164 #define FT_Raster_Done_Func FT_Raster_DoneFunc 1165 1166 1167 /*************************************************************************/ 1168 /* */ 1169 /* <FuncType> */ 1170 /* FT_Raster_ResetFunc */ 1171 /* */ 1172 /* <Description> */ 1173 /* FreeType provides an area of memory called the `render pool', */ 1174 /* available to all registered rasters. This pool can be freely used */ 1175 /* during a given scan-conversion but is shared by all rasters. Its */ 1176 /* content is thus transient. */ 1177 /* */ 1178 /* This function is called each time the render pool changes, or just */ 1179 /* after a new raster object is created. */ 1180 /* */ 1181 /* <Input> */ 1182 /* raster :: A handle to the new raster object. */ 1183 /* */ 1184 /* pool_base :: The address in memory of the render pool. */ 1185 /* */ 1186 /* pool_size :: The size in bytes of the render pool. */ 1187 /* */ 1188 /* <Note> */ 1189 /* Rasters can ignore the render pool and rely on dynamic memory */ 1190 /* allocation if they want to (a handle to the memory allocator is */ 1191 /* passed to the raster constructor). However, this is not */ 1192 /* recommended for efficiency purposes. */ 1193 /* */ 1194 typedef void 1195 (*FT_Raster_ResetFunc)( FT_Raster raster, 1196 unsigned char* pool_base, 1197 unsigned long pool_size ); 1198 1199 #define FT_Raster_Reset_Func FT_Raster_ResetFunc 1200 1201 1202 /*************************************************************************/ 1203 /* */ 1204 /* <FuncType> */ 1205 /* FT_Raster_SetModeFunc */ 1206 /* */ 1207 /* <Description> */ 1208 /* This function is a generic facility to change modes or attributes */ 1209 /* in a given raster. This can be used for debugging purposes, or */ 1210 /* simply to allow implementation-specific `features' in a given */ 1211 /* raster module. */ 1212 /* */ 1213 /* <Input> */ 1214 /* raster :: A handle to the new raster object. */ 1215 /* */ 1216 /* mode :: A 4-byte tag used to name the mode or property. */ 1217 /* */ 1218 /* args :: A pointer to the new mode/property to use. */ 1219 /* */ 1220 typedef int 1221 (*FT_Raster_SetModeFunc)( FT_Raster raster, 1222 unsigned long mode, 1223 void* args ); 1224 1225 #define FT_Raster_Set_Mode_Func FT_Raster_SetModeFunc 1226 1227 1228 /*************************************************************************/ 1229 /* */ 1230 /* <FuncType> */ 1231 /* FT_Raster_RenderFunc */ 1232 /* */ 1233 /* <Description> */ 1234 /* Invoke a given raster to scan-convert a given glyph image into a */ 1235 /* target bitmap. */ 1236 /* */ 1237 /* <Input> */ 1238 /* raster :: A handle to the raster object. */ 1239 /* */ 1240 /* params :: A pointer to an @FT_Raster_Params structure used to */ 1241 /* store the rendering parameters. */ 1242 /* */ 1243 /* <Return> */ 1244 /* Error code. 0~means success. */ 1245 /* */ 1246 /* <Note> */ 1247 /* The exact format of the source image depends on the raster's glyph */ 1248 /* format defined in its @FT_Raster_Funcs structure. It can be an */ 1249 /* @FT_Outline or anything else in order to support a large array of */ 1250 /* glyph formats. */ 1251 /* */ 1252 /* Note also that the render function can fail and return a */ 1253 /* `FT_Err_Unimplemented_Feature' error code if the raster used does */ 1254 /* not support direct composition. */ 1255 /* */ 1256 /* XXX: For now, the standard raster doesn't support direct */ 1257 /* composition but this should change for the final release (see */ 1258 /* the files `demos/src/ftgrays.c' and `demos/src/ftgrays2.c' */ 1259 /* for examples of distinct implementations which support direct */ 1260 /* composition). */ 1261 /* */ 1262 typedef int 1263 (*FT_Raster_RenderFunc)( FT_Raster raster, 1264 const FT_Raster_Params* params ); 1265 1266 #define FT_Raster_Render_Func FT_Raster_RenderFunc 1267 1268 1269 /*************************************************************************/ 1270 /* */ 1271 /* <Struct> */ 1272 /* FT_Raster_Funcs */ 1273 /* */ 1274 /* <Description> */ 1275 /* A structure used to describe a given raster class to the library. */ 1276 /* */ 1277 /* <Fields> */ 1278 /* glyph_format :: The supported glyph format for this raster. */ 1279 /* */ 1280 /* raster_new :: The raster constructor. */ 1281 /* */ 1282 /* raster_reset :: Used to reset the render pool within the raster. */ 1283 /* */ 1284 /* raster_render :: A function to render a glyph into a given bitmap. */ 1285 /* */ 1286 /* raster_done :: The raster destructor. */ 1287 /* */ 1288 typedef struct FT_Raster_Funcs_ 1289 { 1290 FT_Glyph_Format glyph_format; 1291 FT_Raster_NewFunc raster_new; 1292 FT_Raster_ResetFunc raster_reset; 1293 FT_Raster_SetModeFunc raster_set_mode; 1294 FT_Raster_RenderFunc raster_render; 1295 FT_Raster_DoneFunc raster_done; 1296 1297 } FT_Raster_Funcs; 1298 1299 1300 /* */ 1301 1302 1303 FT_END_HEADER 1304 1305 #endif /* __FTIMAGE_H__ */ 1306 1307 1308 /* END */ 1309 1310 1311 /* Local Variables: */ 1312 /* coding: utf-8 */ 1313 /* End: */ 1314
