diff options
Diffstat (limited to 'modules/freetype2/src/base/ftbitmap.c')
| -rw-r--r-- | modules/freetype2/src/base/ftbitmap.c | 1144 |
1 files changed, 1144 insertions, 0 deletions
diff --git a/modules/freetype2/src/base/ftbitmap.c b/modules/freetype2/src/base/ftbitmap.c new file mode 100644 index 0000000000..1c93648dcb --- /dev/null +++ b/modules/freetype2/src/base/ftbitmap.c @@ -0,0 +1,1144 @@ +/**************************************************************************** + * + * ftbitmap.c + * + * FreeType utility functions for bitmaps (body). + * + * Copyright (C) 2004-2023 by + * David Turner, Robert Wilhelm, and Werner Lemberg. + * + * This file is part of the FreeType project, and may only be used, + * modified, and distributed under the terms of the FreeType project + * license, LICENSE.TXT. By continuing to use, modify, or distribute + * this file you indicate that you have read the license and + * understand and accept it fully. + * + */ + + +#include <freetype/internal/ftdebug.h> + +#include <freetype/ftbitmap.h> +#include <freetype/ftimage.h> +#include <freetype/internal/ftobjs.h> + + + /************************************************************************** + * + * The macro FT_COMPONENT is used in trace mode. It is an implicit + * parameter of the FT_TRACE() and FT_ERROR() macros, used to print/log + * messages during execution. + */ +#undef FT_COMPONENT +#define FT_COMPONENT bitmap + + + static + const FT_Bitmap null_bitmap = { 0, 0, 0, NULL, 0, 0, 0, NULL }; + + + /* documentation is in ftbitmap.h */ + + FT_EXPORT_DEF( void ) + FT_Bitmap_Init( FT_Bitmap *abitmap ) + { + if ( abitmap ) + *abitmap = null_bitmap; + } + + + /* deprecated function name; retained for ABI compatibility */ + + FT_EXPORT_DEF( void ) + FT_Bitmap_New( FT_Bitmap *abitmap ) + { + if ( abitmap ) + *abitmap = null_bitmap; + } + + + /* documentation is in ftbitmap.h */ + + FT_EXPORT_DEF( FT_Error ) + FT_Bitmap_Copy( FT_Library library, + const FT_Bitmap *source, + FT_Bitmap *target) + { + FT_Memory memory; + FT_Error error = FT_Err_Ok; + FT_Int pitch; + FT_Int flip; + + + if ( !library ) + return FT_THROW( Invalid_Library_Handle ); + + if ( !source || !target ) + return FT_THROW( Invalid_Argument ); + + if ( source == target ) + return FT_Err_Ok; + + flip = ( source->pitch < 0 && target->pitch > 0 ) || + ( source->pitch > 0 && target->pitch < 0 ); + + memory = library->memory; + FT_FREE( target->buffer ); + + *target = *source; + + if ( flip ) + target->pitch = -target->pitch; + + if ( !source->buffer ) + return FT_Err_Ok; + + pitch = source->pitch; + if ( pitch < 0 ) + pitch = -pitch; + + FT_MEM_QALLOC_MULT( target->buffer, target->rows, pitch ); + + if ( !error ) + { + if ( flip ) + { + /* take care of bitmap flow */ + FT_UInt i; + FT_Byte* s = source->buffer; + FT_Byte* t = target->buffer; + + + t += (FT_ULong)pitch * ( target->rows - 1 ); + + for ( i = target->rows; i > 0; i-- ) + { + FT_ARRAY_COPY( t, s, pitch ); + + s += pitch; + t -= pitch; + } + } + else + FT_MEM_COPY( target->buffer, source->buffer, + (FT_Long)source->rows * pitch ); + } + + return error; + } + + + /* Enlarge `bitmap' horizontally and vertically by `xpixels' */ + /* and `ypixels', respectively. */ + + static FT_Error + ft_bitmap_assure_buffer( FT_Memory memory, + FT_Bitmap* bitmap, + FT_UInt xpixels, + FT_UInt ypixels ) + { + FT_Error error; + unsigned int pitch; + unsigned int new_pitch; + FT_UInt bpp; + FT_UInt width, height; + unsigned char* buffer = NULL; + + + width = bitmap->width; + height = bitmap->rows; + pitch = (unsigned int)FT_ABS( bitmap->pitch ); + + switch ( bitmap->pixel_mode ) + { + case FT_PIXEL_MODE_MONO: + bpp = 1; + new_pitch = ( width + xpixels + 7 ) >> 3; + break; + case FT_PIXEL_MODE_GRAY2: + bpp = 2; + new_pitch = ( width + xpixels + 3 ) >> 2; + break; + case FT_PIXEL_MODE_GRAY4: + bpp = 4; + new_pitch = ( width + xpixels + 1 ) >> 1; + break; + case FT_PIXEL_MODE_GRAY: + case FT_PIXEL_MODE_LCD: + case FT_PIXEL_MODE_LCD_V: + bpp = 8; + new_pitch = width + xpixels; + break; + default: + return FT_THROW( Invalid_Glyph_Format ); + } + + /* if no need to allocate memory */ + if ( ypixels == 0 && new_pitch <= pitch ) + { + /* zero the padding */ + FT_UInt bit_width = pitch * 8; + FT_UInt bit_last = ( width + xpixels ) * bpp; + + + if ( bit_last < bit_width ) + { + FT_Byte* line = bitmap->buffer + ( bit_last >> 3 ); + FT_Byte* end = bitmap->buffer + pitch; + FT_UInt shift = bit_last & 7; + FT_UInt mask = 0xFF00U >> shift; + FT_UInt count = height; + + + for ( ; count > 0; count--, line += pitch, end += pitch ) + { + FT_Byte* write = line; + + + if ( shift > 0 ) + { + write[0] = (FT_Byte)( write[0] & mask ); + write++; + } + if ( write < end ) + FT_MEM_ZERO( write, end - write ); + } + } + + return FT_Err_Ok; + } + + /* otherwise allocate new buffer */ + if ( FT_QALLOC_MULT( buffer, bitmap->rows + ypixels, new_pitch ) ) + return error; + + /* new rows get added at the top of the bitmap, */ + /* thus take care of the flow direction */ + if ( bitmap->pitch > 0 ) + { + FT_UInt len = ( width * bpp + 7 ) >> 3; + + unsigned char* in = bitmap->buffer; + unsigned char* out = buffer; + + unsigned char* limit = bitmap->buffer + pitch * bitmap->rows; + unsigned int delta = new_pitch - len; + + + FT_MEM_ZERO( out, new_pitch * ypixels ); + out += new_pitch * ypixels; + + while ( in < limit ) + { + FT_MEM_COPY( out, in, len ); + in += pitch; + out += len; + + /* we use FT_QALLOC_MULT, which doesn't zero out the buffer; */ + /* consequently, we have to manually zero out the remaining bytes */ + FT_MEM_ZERO( out, delta ); + out += delta; + } + } + else + { + FT_UInt len = ( width * bpp + 7 ) >> 3; + + unsigned char* in = bitmap->buffer; + unsigned char* out = buffer; + + unsigned char* limit = bitmap->buffer + pitch * bitmap->rows; + unsigned int delta = new_pitch - len; + + + while ( in < limit ) + { + FT_MEM_COPY( out, in, len ); + in += pitch; + out += len; + + FT_MEM_ZERO( out, delta ); + out += delta; + } + + FT_MEM_ZERO( out, new_pitch * ypixels ); + } + + FT_FREE( bitmap->buffer ); + bitmap->buffer = buffer; + + /* set pitch only, width and height are left untouched */ + if ( bitmap->pitch < 0 ) + bitmap->pitch = -(int)new_pitch; + else + bitmap->pitch = (int)new_pitch; + + return FT_Err_Ok; + } + + + /* documentation is in ftbitmap.h */ + + FT_EXPORT_DEF( FT_Error ) + FT_Bitmap_Embolden( FT_Library library, + FT_Bitmap* bitmap, + FT_Pos xStrength, + FT_Pos yStrength ) + { + FT_Error error; + unsigned char* p; + FT_Int i, x, pitch; + FT_UInt y; + FT_Int xstr, ystr; + + + if ( !library ) + return FT_THROW( Invalid_Library_Handle ); + + if ( !bitmap || !bitmap->buffer ) + return FT_THROW( Invalid_Argument ); + + if ( ( ( FT_PIX_ROUND( xStrength ) >> 6 ) > FT_INT_MAX ) || + ( ( FT_PIX_ROUND( yStrength ) >> 6 ) > FT_INT_MAX ) ) + return FT_THROW( Invalid_Argument ); + + xstr = (FT_Int)FT_PIX_ROUND( xStrength ) >> 6; + ystr = (FT_Int)FT_PIX_ROUND( yStrength ) >> 6; + + if ( xstr == 0 && ystr == 0 ) + return FT_Err_Ok; + else if ( xstr < 0 || ystr < 0 ) + return FT_THROW( Invalid_Argument ); + + switch ( bitmap->pixel_mode ) + { + case FT_PIXEL_MODE_GRAY2: + case FT_PIXEL_MODE_GRAY4: + { + FT_Bitmap tmp; + + + /* convert to 8bpp */ + FT_Bitmap_Init( &tmp ); + error = FT_Bitmap_Convert( library, bitmap, &tmp, 1 ); + if ( error ) + return error; + + FT_Bitmap_Done( library, bitmap ); + *bitmap = tmp; + } + break; + + case FT_PIXEL_MODE_MONO: + if ( xstr > 8 ) + xstr = 8; + break; + + case FT_PIXEL_MODE_LCD: + xstr *= 3; + break; + + case FT_PIXEL_MODE_LCD_V: + ystr *= 3; + break; + + case FT_PIXEL_MODE_BGRA: + /* We don't embolden color glyphs. */ + return FT_Err_Ok; + } + + error = ft_bitmap_assure_buffer( library->memory, bitmap, + (FT_UInt)xstr, (FT_UInt)ystr ); + if ( error ) + return error; + + /* take care of bitmap flow */ + pitch = bitmap->pitch; + if ( pitch > 0 ) + p = bitmap->buffer + pitch * ystr; + else + { + pitch = -pitch; + p = bitmap->buffer + (FT_UInt)pitch * ( bitmap->rows - 1 ); + } + + /* for each row */ + for ( y = 0; y < bitmap->rows; y++ ) + { + /* + * Horizontally: + * + * From the last pixel on, make each pixel or'ed with the + * `xstr' pixels before it. + */ + for ( x = pitch - 1; x >= 0; x-- ) + { + unsigned char tmp; + + + tmp = p[x]; + for ( i = 1; i <= xstr; i++ ) + { + if ( bitmap->pixel_mode == FT_PIXEL_MODE_MONO ) + { + p[x] |= tmp >> i; + + /* the maximum value of 8 for `xstr' comes from here */ + if ( x > 0 ) + p[x] |= p[x - 1] << ( 8 - i ); + +#if 0 + if ( p[x] == 0xFF ) + break; +#endif + } + else + { + if ( x - i >= 0 ) + { + if ( p[x] + p[x - i] > bitmap->num_grays - 1 ) + { + p[x] = (unsigned char)( bitmap->num_grays - 1 ); + break; + } + else + { + p[x] = (unsigned char)( p[x] + p[x - i] ); + if ( p[x] == bitmap->num_grays - 1 ) + break; + } + } + else + break; + } + } + } + + /* + * Vertically: + * + * Make the above `ystr' rows or'ed with it. + */ + for ( x = 1; x <= ystr; x++ ) + { + unsigned char* q; + + + q = p - bitmap->pitch * x; + for ( i = 0; i < pitch; i++ ) + q[i] |= p[i]; + } + + p += bitmap->pitch; + } + + bitmap->width += (FT_UInt)xstr; + bitmap->rows += (FT_UInt)ystr; + + return FT_Err_Ok; + } + + + static FT_Byte + ft_gray_for_premultiplied_srgb_bgra( const FT_Byte* bgra ) + { + FT_UInt a = bgra[3]; + FT_UInt l; + + + /* Short-circuit transparent color to avoid division by zero. */ + if ( !a ) + return 0; + + /* + * Luminosity for sRGB is defined using ~0.2126,0.7152,0.0722 + * coefficients for RGB channels *on the linear colors*. + * A gamma of 2.2 is fair to assume. And then, we need to + * undo the premultiplication too. + * + * http://www.brucelindbloom.com/index.html?WorkingSpaceInfo.html#SideNotes + * + * We do the computation with integers only, applying a gamma of 2.0. + * We guarantee 32-bit arithmetic to avoid overflow but the resulting + * luminosity fits into 16 bits. + * + */ + + l = ( 4731UL /* 0.072186 * 65536 */ * bgra[0] * bgra[0] + + 46868UL /* 0.715158 * 65536 */ * bgra[1] * bgra[1] + + 13937UL /* 0.212656 * 65536 */ * bgra[2] * bgra[2] ) >> 16; + + /* + * Final transparency can be determined as follows. + * + * - If alpha is zero, we want 0. + * - If alpha is zero and luminosity is zero, we want 255. + * - If alpha is zero and luminosity is one, we want 0. + * + * So the formula is a * (1 - l) = a - l * a. + * + * We still need to undo premultiplication by dividing l by a*a. + * + */ + + return (FT_Byte)( a - l / a ); + } + + + /* documentation is in ftbitmap.h */ + + FT_EXPORT_DEF( FT_Error ) + FT_Bitmap_Convert( FT_Library library, + const FT_Bitmap *source, + FT_Bitmap *target, + FT_Int alignment ) + { + FT_Error error = FT_Err_Ok; + FT_Memory memory; + + FT_Byte* s; + FT_Byte* t; + + + if ( !library ) + return FT_THROW( Invalid_Library_Handle ); + + if ( !source || !target ) + return FT_THROW( Invalid_Argument ); + + memory = library->memory; + + switch ( source->pixel_mode ) + { + case FT_PIXEL_MODE_MONO: + case FT_PIXEL_MODE_GRAY: + case FT_PIXEL_MODE_GRAY2: + case FT_PIXEL_MODE_GRAY4: + case FT_PIXEL_MODE_LCD: + case FT_PIXEL_MODE_LCD_V: + case FT_PIXEL_MODE_BGRA: + { + FT_Int width = (FT_Int)source->width; + FT_Int neg = ( target->pitch == 0 && source->pitch < 0 ) || + target->pitch < 0; + + + FT_Bitmap_Done( library, target ); + + target->pixel_mode = FT_PIXEL_MODE_GRAY; + target->rows = source->rows; + target->width = source->width; + + if ( alignment ) + { + FT_Int rem = width % alignment; + + + if ( rem ) + width = alignment > 0 ? width - rem + alignment + : width - rem - alignment; + } + + if ( FT_QALLOC_MULT( target->buffer, target->rows, width ) ) + return error; + + target->pitch = neg ? -width : width; + } + break; + + default: + error = FT_THROW( Invalid_Argument ); + } + + s = source->buffer; + t = target->buffer; + + /* take care of bitmap flow */ + if ( source->pitch < 0 ) + s -= source->pitch * (FT_Int)( source->rows - 1 ); + if ( target->pitch < 0 ) + t -= target->pitch * (FT_Int)( target->rows - 1 ); + + switch ( source->pixel_mode ) + { + case FT_PIXEL_MODE_MONO: + { + FT_UInt i; + + + target->num_grays = 2; + + for ( i = source->rows; i > 0; i-- ) + { + FT_Byte* ss = s; + FT_Byte* tt = t; + FT_UInt j; + + + /* get the full bytes */ + for ( j = source->width >> 3; j > 0; j-- ) + { + FT_Int val = ss[0]; /* avoid a byte->int cast on each line */ + + + tt[0] = (FT_Byte)( ( val & 0x80 ) >> 7 ); + tt[1] = (FT_Byte)( ( val & 0x40 ) >> 6 ); + tt[2] = (FT_Byte)( ( val & 0x20 ) >> 5 ); + tt[3] = (FT_Byte)( ( val & 0x10 ) >> 4 ); + tt[4] = (FT_Byte)( ( val & 0x08 ) >> 3 ); + tt[5] = (FT_Byte)( ( val & 0x04 ) >> 2 ); + tt[6] = (FT_Byte)( ( val & 0x02 ) >> 1 ); + tt[7] = (FT_Byte)( val & 0x01 ); + + tt += 8; + ss += 1; + } + + /* get remaining pixels (if any) */ + j = source->width & 7; + if ( j > 0 ) + { + FT_Int val = *ss; + + + for ( ; j > 0; j-- ) + { + tt[0] = (FT_Byte)( ( val & 0x80 ) >> 7); + val <<= 1; + tt += 1; + } + } + + s += source->pitch; + t += target->pitch; + } + } + break; + + + case FT_PIXEL_MODE_GRAY: + case FT_PIXEL_MODE_LCD: + case FT_PIXEL_MODE_LCD_V: + { + FT_UInt width = source->width; + FT_UInt i; + + + target->num_grays = 256; + + for ( i = source->rows; i > 0; i-- ) + { + FT_ARRAY_COPY( t, s, width ); + + s += source->pitch; + t += target->pitch; + } + } + break; + + + case FT_PIXEL_MODE_GRAY2: + { + FT_UInt i; + + + target->num_grays = 4; + + for ( i = source->rows; i > 0; i-- ) + { + FT_Byte* ss = s; + FT_Byte* tt = t; + FT_UInt j; + + + /* get the full bytes */ + for ( j = source->width >> 2; j > 0; j-- ) + { + FT_Int val = ss[0]; + + + tt[0] = (FT_Byte)( ( val & 0xC0 ) >> 6 ); + tt[1] = (FT_Byte)( ( val & 0x30 ) >> 4 ); + tt[2] = (FT_Byte)( ( val & 0x0C ) >> 2 ); + tt[3] = (FT_Byte)( ( val & 0x03 ) ); + + ss += 1; + tt += 4; + } + + j = source->width & 3; + if ( j > 0 ) + { + FT_Int val = ss[0]; + + + for ( ; j > 0; j-- ) + { + tt[0] = (FT_Byte)( ( val & 0xC0 ) >> 6 ); + val <<= 2; + tt += 1; + } + } + + s += source->pitch; + t += target->pitch; + } + } + break; + + + case FT_PIXEL_MODE_GRAY4: + { + FT_UInt i; + + + target->num_grays = 16; + + for ( i = source->rows; i > 0; i-- ) + { + FT_Byte* ss = s; + FT_Byte* tt = t; + FT_UInt j; + + + /* get the full bytes */ + for ( j = source->width >> 1; j > 0; j-- ) + { + FT_Int val = ss[0]; + + + tt[0] = (FT_Byte)( ( val & 0xF0 ) >> 4 ); + tt[1] = (FT_Byte)( ( val & 0x0F ) ); + + ss += 1; + tt += 2; + } + + if ( source->width & 1 ) + tt[0] = (FT_Byte)( ( ss[0] & 0xF0 ) >> 4 ); + + s += source->pitch; + t += target->pitch; + } + } + break; + + + case FT_PIXEL_MODE_BGRA: + { + FT_UInt i; + + + target->num_grays = 256; + + for ( i = source->rows; i > 0; i-- ) + { + FT_Byte* ss = s; + FT_Byte* tt = t; + FT_UInt j; + + + for ( j = source->width; j > 0; j-- ) + { + tt[0] = ft_gray_for_premultiplied_srgb_bgra( ss ); + + ss += 4; + tt += 1; + } + + s += source->pitch; + t += target->pitch; + } + } + break; + + default: + ; + } + + return error; + } + + + /* documentation is in ftbitmap.h */ + + FT_EXPORT_DEF( FT_Error ) + FT_Bitmap_Blend( FT_Library library, + const FT_Bitmap* source_, + const FT_Vector source_offset_, + FT_Bitmap* target, + FT_Vector *atarget_offset, + FT_Color color ) + { + FT_Error error = FT_Err_Ok; + FT_Memory memory; + + FT_Bitmap source_bitmap; + const FT_Bitmap* source; + + FT_Vector source_offset; + FT_Vector target_offset; + + FT_Bool free_source_bitmap = 0; + FT_Bool free_target_bitmap_on_error = 0; + + FT_Pos source_llx, source_lly, source_urx, source_ury; + FT_Pos target_llx, target_lly, target_urx, target_ury; + FT_Pos final_llx, final_lly, final_urx, final_ury; + + unsigned int final_rows, final_width; + long x, y; + + + if ( !library || !target || !source_ || !atarget_offset ) + return FT_THROW( Invalid_Argument ); + + memory = library->memory; + + if ( !( target->pixel_mode == FT_PIXEL_MODE_NONE || + ( target->pixel_mode == FT_PIXEL_MODE_BGRA && + target->buffer ) ) ) + return FT_THROW( Invalid_Argument ); + + if ( source_->pixel_mode == FT_PIXEL_MODE_NONE ) + return FT_Err_Ok; /* nothing to do */ + + /* pitches must have the same sign */ + if ( target->pixel_mode == FT_PIXEL_MODE_BGRA && + ( source_->pitch ^ target->pitch ) < 0 ) + return FT_THROW( Invalid_Argument ); + + if ( !( source_->width && source_->rows ) ) + return FT_Err_Ok; /* nothing to do */ + + /* assure integer pixel offsets */ + source_offset.x = FT_PIX_FLOOR( source_offset_.x ); + source_offset.y = FT_PIX_FLOOR( source_offset_.y ); + target_offset.x = FT_PIX_FLOOR( atarget_offset->x ); + target_offset.y = FT_PIX_FLOOR( atarget_offset->y ); + + /* get source bitmap dimensions */ + source_llx = source_offset.x; + if ( FT_LONG_MIN + (FT_Pos)( source_->rows << 6 ) + 64 > source_offset.y ) + { + FT_TRACE5(( + "FT_Bitmap_Blend: y coordinate overflow in source bitmap\n" )); + return FT_THROW( Invalid_Argument ); + } + source_lly = source_offset.y - ( source_->rows << 6 ); + + if ( FT_LONG_MAX - (FT_Pos)( source_->width << 6 ) - 64 < source_llx ) + { + FT_TRACE5(( + "FT_Bitmap_Blend: x coordinate overflow in source bitmap\n" )); + return FT_THROW( Invalid_Argument ); + } + source_urx = source_llx + ( source_->width << 6 ); + source_ury = source_offset.y; + + /* get target bitmap dimensions */ + if ( target->width && target->rows ) + { + target_llx = target_offset.x; + if ( FT_LONG_MIN + (FT_Pos)( target->rows << 6 ) > target_offset.y ) + { + FT_TRACE5(( + "FT_Bitmap_Blend: y coordinate overflow in target bitmap\n" )); + return FT_THROW( Invalid_Argument ); + } + target_lly = target_offset.y - ( target->rows << 6 ); + + if ( FT_LONG_MAX - (FT_Pos)( target->width << 6 ) < target_llx ) + { + FT_TRACE5(( + "FT_Bitmap_Blend: x coordinate overflow in target bitmap\n" )); + return FT_THROW( Invalid_Argument ); + } + target_urx = target_llx + ( target->width << 6 ); + target_ury = target_offset.y; + } + else + { + target_llx = FT_LONG_MAX; + target_lly = FT_LONG_MAX; + target_urx = FT_LONG_MIN; + target_ury = FT_LONG_MIN; + } + + /* compute final bitmap dimensions */ + final_llx = FT_MIN( source_llx, target_llx ); + final_lly = FT_MIN( source_lly, target_lly ); + final_urx = FT_MAX( source_urx, target_urx ); + final_ury = FT_MAX( source_ury, target_ury ); + + final_width = ( final_urx - final_llx ) >> 6; + final_rows = ( final_ury - final_lly ) >> 6; + +#ifdef FT_DEBUG_LEVEL_TRACE + FT_TRACE5(( "FT_Bitmap_Blend:\n" )); + FT_TRACE5(( " source bitmap: (%ld, %ld) -- (%ld, %ld); %d x %d\n", + source_llx / 64, source_lly / 64, + source_urx / 64, source_ury / 64, + source_->width, source_->rows )); + + if ( target->width && target->rows ) + FT_TRACE5(( " target bitmap: (%ld, %ld) -- (%ld, %ld); %d x %d\n", + target_llx / 64, target_lly / 64, + target_urx / 64, target_ury / 64, + target->width, target->rows )); + else + FT_TRACE5(( " target bitmap: empty\n" )); + + if ( final_width && final_rows ) + FT_TRACE5(( " final bitmap: (%ld, %ld) -- (%ld, %ld); %d x %d\n", + final_llx / 64, final_lly / 64, + final_urx / 64, final_ury / 64, + final_width, final_rows )); + else + FT_TRACE5(( " final bitmap: empty\n" )); +#endif /* FT_DEBUG_LEVEL_TRACE */ + + if ( !( final_width && final_rows ) ) + return FT_Err_Ok; /* nothing to do */ + + /* for blending, set offset vector of final bitmap */ + /* temporarily to (0,0) */ + source_llx -= final_llx; + source_lly -= final_lly; + + if ( target->width && target->rows ) + { + target_llx -= final_llx; + target_lly -= final_lly; + } + + /* set up target bitmap */ + if ( target->pixel_mode == FT_PIXEL_MODE_NONE ) + { + /* create new empty bitmap */ + target->width = final_width; + target->rows = final_rows; + target->pixel_mode = FT_PIXEL_MODE_BGRA; + target->pitch = (int)final_width * 4; + target->num_grays = 256; + + if ( FT_LONG_MAX / target->pitch < (int)target->rows ) + { + FT_TRACE5(( "FT_Blend_Bitmap: target bitmap too large (%d x %d)\n", + final_width, final_rows )); + return FT_THROW( Invalid_Argument ); + } + + if ( FT_ALLOC( target->buffer, target->pitch * (int)target->rows ) ) + return error; + + free_target_bitmap_on_error = 1; + } + else if ( target->width != final_width || + target->rows != final_rows ) + { + /* adjust old bitmap to enlarged size */ + int pitch, new_pitch; + + unsigned char* buffer = NULL; + + + pitch = target->pitch; + + if ( pitch < 0 ) + pitch = -pitch; + + new_pitch = (int)final_width * 4; + + if ( FT_LONG_MAX / new_pitch < (int)final_rows ) + { + FT_TRACE5(( "FT_Blend_Bitmap: target bitmap too large (%d x %d)\n", + final_width, final_rows )); + return FT_THROW( Invalid_Argument ); + } + + /* TODO: provide an in-buffer solution for large bitmaps */ + /* to avoid allocation of a new buffer */ + if ( FT_ALLOC( buffer, new_pitch * (int)final_rows ) ) + goto Error; + + /* copy data to new buffer */ + x = target_llx >> 6; + y = target_lly >> 6; + + /* the bitmap flow is from top to bottom, */ + /* but y is measured from bottom to top */ + if ( target->pitch < 0 ) + { + /* XXX */ + } + else + { + unsigned char* p = + target->buffer; + unsigned char* q = + buffer + + ( final_rows - y - target->rows ) * new_pitch + + x * 4; + unsigned char* limit_p = + p + pitch * (int)target->rows; + + + while ( p < limit_p ) + { + FT_MEM_COPY( q, p, pitch ); + + p += pitch; + q += new_pitch; + } + } + + FT_FREE( target->buffer ); + + target->width = final_width; + target->rows = final_rows; + + if ( target->pitch < 0 ) + target->pitch = -new_pitch; + else + target->pitch = new_pitch; + + target->buffer = buffer; + } + + /* adjust source bitmap if necessary */ + if ( source_->pixel_mode != FT_PIXEL_MODE_GRAY ) + { + FT_Bitmap_Init( &source_bitmap ); + error = FT_Bitmap_Convert( library, source_, &source_bitmap, 1 ); + if ( error ) + goto Error; + + source = &source_bitmap; + free_source_bitmap = 1; + } + else + source = source_; + + /* do blending; the code below returns pre-multiplied channels, */ + /* similar to what FreeType gets from `CBDT' tables */ + x = source_llx >> 6; + y = source_lly >> 6; + + /* the bitmap flow is from top to bottom, */ + /* but y is measured from bottom to top */ + if ( target->pitch < 0 ) + { + /* XXX */ + } + else + { + unsigned char* p = + source->buffer; + unsigned char* q = + target->buffer + + ( target->rows - y - source->rows ) * target->pitch + + x * 4; + unsigned char* limit_p = + p + source->pitch * (int)source->rows; + + + while ( p < limit_p ) + { + unsigned char* r = p; + unsigned char* s = q; + unsigned char* limit_r = r + source->width; + + + while ( r < limit_r ) + { + int aa = *r++; + int fa = color.alpha * aa / 255; + + int fb = color.blue * fa / 255; + int fg = color.green * fa / 255; + int fr = color.red * fa / 255; + + int ba2 = 255 - fa; + + int bb = s[0]; + int bg = s[1]; + int br = s[2]; + int ba = s[3]; + + + *s++ = (unsigned char)( bb * ba2 / 255 + fb ); + *s++ = (unsigned char)( bg * ba2 / 255 + fg ); + *s++ = (unsigned char)( br * ba2 / 255 + fr ); + *s++ = (unsigned char)( ba * ba2 / 255 + fa ); + } + + p += source->pitch; + q += target->pitch; + } + } + + atarget_offset->x = final_llx; + atarget_offset->y = final_lly + ( final_rows << 6 ); + + Error: + if ( error && free_target_bitmap_on_error ) + FT_Bitmap_Done( library, target ); + + if ( free_source_bitmap ) + FT_Bitmap_Done( library, &source_bitmap ); + + return error; + } + + + /* documentation is in ftbitmap.h */ + + FT_EXPORT_DEF( FT_Error ) + FT_GlyphSlot_Own_Bitmap( FT_GlyphSlot slot ) + { + if ( slot && slot->format == FT_GLYPH_FORMAT_BITMAP && + !( slot->internal->flags & FT_GLYPH_OWN_BITMAP ) ) + { + FT_Bitmap bitmap; + FT_Error error; + + + FT_Bitmap_Init( &bitmap ); + error = FT_Bitmap_Copy( slot->library, &slot->bitmap, &bitmap ); + if ( error ) + return error; + + slot->bitmap = bitmap; + slot->internal->flags |= FT_GLYPH_OWN_BITMAP; + } + + return FT_Err_Ok; + } + + + /* documentation is in ftbitmap.h */ + + FT_EXPORT_DEF( FT_Error ) + FT_Bitmap_Done( FT_Library library, + FT_Bitmap *bitmap ) + { + FT_Memory memory; + + + if ( !library ) + return FT_THROW( Invalid_Library_Handle ); + + if ( !bitmap ) + return FT_THROW( Invalid_Argument ); + + memory = library->memory; + + FT_FREE( bitmap->buffer ); + *bitmap = null_bitmap; + + return FT_Err_Ok; + } + + +/* END */ |