ReFuel/freetype
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

[base] Clean up trigonometric core.

Browse Source 
* src/base/fttrrigon.c (ft_trig_pseudo_polarize): Align algorithm
with `ft_trig_pseudo_rotate'.
This commit is contained in:
Alexei Podtelezhnikov 2012-12-19 22:46:27 -05:00
parent 1749ae20a7
commit 06174dbb20
2 changed files with 29 additions and 25 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

7
ChangeLog
View File

@ -1,3 +1,10 @@
2012-12-19 Alexei Podtelezhnikov <apodtele@gmail.com>
[base] Clean up trigonometric core.
* src/base/fttrrigon.c (ft_trig_pseudo_polarize): Align algorithm
with `ft_trig_pseudo_rotate'.
2012-12-18 Infinality <infinality@infinality.net>
[truetype] Minor performance enhancement.

47
src/base/fttrigon.c
View File

@ -260,9 +260,9 @@
static void
ft_trig_pseudo_polarize( FT_Vector* vec )
{
FT_Fixed theta;
FT_Fixed yi, i;
FT_Fixed x, y;
FT_Angle theta;
FT_Int i;
FT_Fixed x, y, xtemp;
const FT_Fixed *arctanptr;
@ -283,41 +283,38 @@
arctanptr = ft_trig_arctan_table;
if ( y < 0 )
if ( y > 0 )
{
/* Rotate positive */
yi = y + ( x << 1 );
x = x - ( y << 1 );
y = yi;
theta -= *arctanptr++; /* Subtract angle */
xtemp = x + ( y << 1 );
y = y - ( x << 1 );
x = xtemp;
theta += *arctanptr++;
}
else
{
/* Rotate negative */
yi = y - ( x << 1 );
x = x + ( y << 1 );
y = yi;
theta += *arctanptr++; /* Add angle */
xtemp = x - ( y << 1 );
y = y + ( x << 1 );
x = xtemp;
theta -= *arctanptr++;
}
/* Subsequent pseudorotations, with right shifts */
i = 0;
do
{
if ( y < 0 )
if ( y > 0 )
{
/* Rotate positive */
yi = y + ( x >> i );
x = x - ( y >> i );
y = yi;
theta -= *arctanptr++;
xtemp = x + ( y >> i );
y = y - ( x >> i );
x = xtemp;
theta += *arctanptr++;
}
else
{
/* Rotate negative */
yi = y - ( x >> i );
x = x + ( y >> i );
y = yi;
theta += *arctanptr++;
xtemp = x - ( y >> i );
y = y + ( x >> i );
x = xtemp;
theta -= *arctanptr++;
}
} while ( ++i < FT_TRIG_MAX_ITERS );