diff options
Diffstat (limited to 'third_party/freetype/src/base/ftbitmap.c')
| -rw-r--r-- | third_party/freetype/src/base/ftbitmap.c | 796 |
1 files changed, 796 insertions, 0 deletions
diff --git a/third_party/freetype/src/base/ftbitmap.c b/third_party/freetype/src/base/ftbitmap.c new file mode 100644 index 0000000000..5dd33a26f1 --- /dev/null +++ b/third_party/freetype/src/base/ftbitmap.c @@ -0,0 +1,796 @@ +/***************************************************************************/ +/* */ +/* ftbitmap.c */ +/* */ +/* FreeType utility functions for bitmaps (body). */ +/* */ +/* Copyright 2004-2009, 2011, 2013, 2014 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 <ft2build.h> +#include FT_INTERNAL_DEBUG_H + +#include FT_BITMAP_H +#include FT_IMAGE_H +#include FT_INTERNAL_OBJECTS_H + + + static + const FT_Bitmap null_bitmap = { 0, 0, 0, 0, 0, 0, 0, 0 }; + + + /* documentation is in ftbitmap.h */ + + 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_ULong size; + + FT_Int source_pitch_sign, target_pitch_sign; + + + if ( !library ) + return FT_THROW( Invalid_Library_Handle ); + + if ( !source || !target ) + return FT_THROW( Invalid_Argument ); + + if ( source == target ) + return FT_Err_Ok; + + source_pitch_sign = source->pitch < 0 ? -1 : 1; + target_pitch_sign = target->pitch < 0 ? -1 : 1; + + if ( source->buffer == NULL ) + { + *target = *source; + if ( source_pitch_sign != target_pitch_sign ) + target->pitch = -target->pitch; + + return FT_Err_Ok; + } + + memory = library->memory; + pitch = source->pitch; + + if ( pitch < 0 ) + pitch = -pitch; + size = (FT_ULong)pitch * source->rows; + + if ( target->buffer ) + { + FT_Int target_pitch = target->pitch; + FT_ULong target_size; + + + if ( target_pitch < 0 ) + target_pitch = -target_pitch; + target_size = (FT_ULong)target_pitch * target->rows; + + if ( target_size != size ) + (void)FT_QREALLOC( target->buffer, target_size, size ); + } + else + (void)FT_QALLOC( target->buffer, size ); + + if ( !error ) + { + unsigned char *p; + + + p = target->buffer; + *target = *source; + target->buffer = p; + + if ( source_pitch_sign == target_pitch_sign ) + FT_MEM_COPY( target->buffer, source->buffer, size ); + else + { + /* take care of bitmap flow */ + FT_UInt i; + FT_Byte* s = source->buffer; + FT_Byte* t = target->buffer; + + + t += pitch * ( target->rows - 1 ); + + for ( i = target->rows; i > 0; i-- ) + { + FT_ARRAY_COPY( t, s, pitch ); + + s += pitch; + t -= 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; + int pitch; + int new_pitch; + FT_UInt bpp; + FT_UInt i, width, height; + unsigned char* buffer = NULL; + + + width = bitmap->width; + height = bitmap->rows; + pitch = bitmap->pitch; + if ( pitch < 0 ) + pitch = -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, new_pitch, bitmap->rows + ypixels ) ) + 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; + + + for ( i = 0; i < bitmap->rows; i++ ) + FT_MEM_COPY( buffer + new_pitch * ( ypixels + i ), + bitmap->buffer + pitch * i, len ); + } + else + { + FT_UInt len = ( width * bpp + 7 ) >> 3; + + + for ( i = 0; i < bitmap->rows; i++ ) + FT_MEM_COPY( buffer + new_pitch * i, + bitmap->buffer + pitch * i, len ); + } + + FT_FREE( bitmap->buffer ); + bitmap->buffer = buffer; + + if ( bitmap->pitch < 0 ) + new_pitch = -new_pitch; + + /* set pitch only, width and height are left untouched */ + bitmap->pitch = 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_New( &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, xstr, 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 + 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 += xstr; + bitmap->rows += 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://accessibility.kde.org/hsl-adjusted.php + * + * 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 = ( 4732UL /* 0.0722 * 65536 */ * bgra[0] * bgra[0] + + 46871UL /* 0.7152 * 65536 */ * bgra[1] * bgra[1] + + 13933UL /* 0.2126 * 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 pad, old_target_pitch, target_pitch; + FT_ULong old_size; + + + old_target_pitch = target->pitch; + if ( old_target_pitch < 0 ) + old_target_pitch = -old_target_pitch; + + old_size = target->rows * old_target_pitch; + + target->pixel_mode = FT_PIXEL_MODE_GRAY; + target->rows = source->rows; + target->width = source->width; + + pad = 0; + if ( alignment > 0 ) + { + pad = source->width % alignment; + if ( pad != 0 ) + pad = alignment - pad; + } + + target_pitch = source->width + pad; + + if ( target_pitch > 0 && + (FT_ULong)target->rows > FT_ULONG_MAX / target_pitch ) + return FT_THROW( Invalid_Argument ); + + if ( target->rows * target_pitch > old_size && + FT_QREALLOC( target->buffer, + old_size, target->rows * target_pitch ) ) + return error; + + target->pitch = target->pitch < 0 ? -target_pitch : target_pitch; + } + 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 * ( source->rows - 1 ); + if ( target->pitch < 0 ) + t -= target->pitch * ( 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_Int 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_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_New( &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 */ |