| #include "aftypes.h" |
| |
| /* this table was generated for AF_ANGLE_PI = 256 */ |
| #define AF_ANGLE_MAX_ITERS 8 |
| #define AF_TRIG_MAX_ITERS 9 |
| |
| static const FT_Fixed |
| af_angle_arctan_table[9] = |
| { |
| 90, 64, 38, 20, 10, 5, 3, 1, 1 |
| }; |
| |
| |
| static FT_Int |
| af_angle_prenorm( FT_Vector* vec ) |
| { |
| FT_Fixed x, y, z; |
| FT_Int shift; |
| |
| |
| x = vec->x; |
| y = vec->y; |
| |
| z = ( ( x >= 0 ) ? x : - x ) | ( (y >= 0) ? y : -y ); |
| shift = 0; |
| |
| if ( z < ( 1L << 27 ) ) |
| { |
| do |
| { |
| shift++; |
| z <<= 1; |
| } while ( z < ( 1L << 27 ) ); |
| |
| vec->x = x << shift; |
| vec->y = y << shift; |
| } |
| else if ( z > ( 1L << 28 ) ) |
| { |
| do |
| { |
| shift++; |
| z >>= 1; |
| } while ( z > ( 1L << 28 ) ); |
| |
| vec->x = x >> shift; |
| vec->y = y >> shift; |
| shift = -shift; |
| } |
| return shift; |
| } |
| |
| |
| static void |
| af_angle_pseudo_polarize( FT_Vector* vec ) |
| { |
| FT_Fixed theta; |
| FT_Fixed yi, i; |
| FT_Fixed x, y; |
| const FT_Fixed *arctanptr; |
| |
| |
| x = vec->x; |
| y = vec->y; |
| |
| /* Get the vector into the right half plane */ |
| theta = 0; |
| if ( x < 0 ) |
| { |
| x = -x; |
| y = -y; |
| theta = 2 * AF_ANGLE_PI2; |
| } |
| |
| if ( y > 0 ) |
| theta = - theta; |
| |
| arctanptr = af_angle_arctan_table; |
| |
| if ( y < 0 ) |
| { |
| /* Rotate positive */ |
| yi = y + ( x << 1 ); |
| x = x - ( y << 1 ); |
| y = yi; |
| theta -= *arctanptr++; /* Subtract angle */ |
| } |
| else |
| { |
| /* Rotate negative */ |
| yi = y - ( x << 1 ); |
| x = x + ( y << 1 ); |
| y = yi; |
| theta += *arctanptr++; /* Add angle */ |
| } |
| |
| i = 0; |
| do |
| { |
| if ( y < 0 ) |
| { |
| /* Rotate positive */ |
| yi = y + ( x >> i ); |
| x = x - ( y >> i ); |
| y = yi; |
| theta -= *arctanptr++; |
| } |
| else |
| { |
| /* Rotate negative */ |
| yi = y - ( x >> i ); |
| x = x + ( y >> i ); |
| y = yi; |
| theta += *arctanptr++; |
| } |
| } while ( ++i < AF_TRIG_MAX_ITERS ); |
| |
| /* round theta */ |
| if ( theta >= 0 ) |
| theta = FT_PAD_ROUND( theta, 4 ); |
| else |
| theta = - FT_PAD_ROUND( theta, 4 ); |
| |
| vec->x = x; |
| vec->y = theta; |
| } |
| |
| |
| /* documentation is in fttrigon.h */ |
| |
| FT_LOCAL_DEF( AF_Angle ) |
| af_angle_atan( FT_Fixed dx, |
| FT_Fixed dy ) |
| { |
| FT_Vector v; |
| |
| |
| if ( dx == 0 && dy == 0 ) |
| return 0; |
| |
| v.x = dx; |
| v.y = dy; |
| af_angle_prenorm( &v ); |
| af_angle_pseudo_polarize( &v ); |
| |
| return v.y; |
| } |
| |
| |
| |
| FT_LOCAL_DEF( AF_Angle ) |
| af_angle_diff( AF_Angle angle1, |
| AF_Angle angle2 ) |
| { |
| AF_Angle delta = angle2 - angle1; |
| |
| delta %= AF_ANGLE_2PI; |
| if ( delta < 0 ) |
| delta += AF_ANGLE_2PI; |
| |
| if ( delta > AF_ANGLE_PI ) |
| delta -= AF_ANGLE_2PI; |
| |
| return delta; |
| } |
| |
| |
| /* well, this needs to be somewhere, right :-) |
| */ |
| |
| FT_LOCAL_DEF( void ) |
| af_sort_pos( FT_UInt count, |
| FT_Pos* table ) |
| { |
| FT_UInt i, j; |
| FT_Pos swap; |
| |
| |
| for ( i = 1; i < count; i++ ) |
| { |
| for ( j = i; j > 0; j-- ) |
| { |
| if ( table[j] > table[j - 1] ) |
| break; |
| |
| swap = table[j]; |
| table[j] = table[j - 1]; |
| table[j - 1] = swap; |
| } |
| } |
| } |
| |
| |
| FT_LOCAL_DEF( void ) |
| af_sort_widths( FT_UInt count, |
| AF_Width table ) |
| { |
| FT_UInt i, j; |
| AF_WidthRec swap; |
| |
| |
| for ( i = 1; i < count; i++ ) |
| { |
| for ( j = i; j > 0; j-- ) |
| { |
| if ( table[j].org > table[j - 1].org ) |
| break; |
| |
| swap = table[j]; |
| table[j] = table[j - 1]; |
| table[j - 1] = swap; |
| } |
| } |
| } |