ref: a35b081ebc16e1bf79fe29ec9ecbb369019ed04e
parent: bad92be9270c8952ca5367e6e1d48bc4d26d4fa1
author: Alexei Podtelezhnikov <apodtele@gmail.com>
date: Sat Dec 11 17:12:25 EST 2021
[truetype] Limit INSTCTRL appication within specs. * src/truetype/ttinterp.c (Ins_INSTCTRL): Limit its global effects to the CVT program and local effects to the glyph program. This also fixes an Infinality buglet. The `ignore_x_mode` should be locally unset by the glyph program.
--- a/src/truetype/ttinterp.c
+++ b/src/truetype/ttinterp.c
@@ -5260,16 +5260,21 @@
}
}
- exc->GS.instruct_control &= ~(FT_Byte)Kf;
- exc->GS.instruct_control |= (FT_Byte)L;
+ /* INSTCTRL should only be used in the CVT program */
+ if ( exc->iniRange == tt_coderange_cvt )
+ {
+ exc->GS.instruct_control &= ~(FT_Byte)Kf;
+ exc->GS.instruct_control |= (FT_Byte)L;
+ }
- if ( K == 3 )
+ /* except to change the subpixel flags temporarily */
+ else if ( exc->iniRange == tt_coderange_glyph && K == 3 )
{
#ifdef TT_SUPPORT_SUBPIXEL_HINTING_INFINALITY
/* INSTCTRL modifying flag 3 also has an effect */
/* outside of the CVT program */
if ( SUBPIXEL_HINTING_INFINALITY )
- exc->ignore_x_mode = FT_BOOL( L == 4 );
+ exc->ignore_x_mode = !FT_BOOL( L == 4 );
#endif
#ifdef TT_SUPPORT_SUBPIXEL_HINTING_MINIMAL
@@ -5280,6 +5285,8 @@
exc->backward_compatibility = !FT_BOOL( L == 4 );
#endif
}
+ else if ( exc->pedantic_hinting )
+ exc->error = FT_THROW( Invalid_Reference );
}