ref: e0843609616c5f12b3d1697499c839d3e89f96fb
parent: 32a320625e333a7728b04a35d7953b3508b80f04
author: Werner Lemberg <[email protected]>
date: Sat Jul 16 14:46:28 EDT 2016
[truetype] Add bytecode support for GX variation fonts.
This commit implements undocumented (but confirmed) stuff from
Apple's old bytecode engine.
GETVARIATION[], opcode 0x91
This opcode pushes normalized variation coordinates for all axes
onto the stack (in 2.14 format). Coordinate of first axis gets
pushed first.
GETINFO[], selector bit 3
If GX variation support is enabled, bit 10 of the result is set
to 1.
* src/truetype/ttinterp.c: Include FT_MULTIPLE_MASTERS_H.
(opcode_name) [TT_CONFIG_OPTION_GX_VAR_SUPPORT]: Updated.
(Ins_GETINFO) [TT_CONFIG_OPTION_GX_VAR_SUPPORT]: Handle selector
bit 3, checking support for variation glyph hinting.
(Ins_GETVARIATION) [TT_CONFIG_OPTION_GX_VAR_SUPPORT]: New function
to implement opcode 0x91.
(TT_RunIns) [TT_CONFIG_OPTION_GX_VAR_SUPPORT]: Handle opcode 0x91.
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,5 +1,29 @@
2016-07-16 Werner Lemberg <[email protected]>
+ [truetype] Add bytecode support for GX variation fonts.
+
+ This commit implements undocumented (but confirmed) stuff from
+ Apple's old bytecode engine.
+
+ GETVARIATION[], opcode 0x91
+ This opcode pushes normalized variation coordinates for all axes
+ onto the stack (in 2.14 format). Coordinate of first axis gets
+ pushed first.
+
+ GETINFO[], selector bit 3
+ If GX variation support is enabled, bit 10 of the result is set
+ to 1.
+
+ * src/truetype/ttinterp.c: Include FT_MULTIPLE_MASTERS_H.
+ (opcode_name) [TT_CONFIG_OPTION_GX_VAR_SUPPORT]: Updated.
+ (Ins_GETINFO) [TT_CONFIG_OPTION_GX_VAR_SUPPORT]: Handle selector
+ bit 3, checking support for variation glyph hinting.
+ (Ins_GETVARIATION) [TT_CONFIG_OPTION_GX_VAR_SUPPORT]: New function
+ to implement opcode 0x91.
+ (TT_RunIns) [TT_CONFIG_OPTION_GX_VAR_SUPPORT]: Handle opcode 0x91.
+
+2016-07-16 Werner Lemberg <[email protected]>
+
[truetype] Fix GETINFO bytecode instruction.
* src/truetype/ttinterp.c (Ins_GETINFO): Fix return value for
--- a/src/truetype/ttinterp.c
+++ b/src/truetype/ttinterp.c
@@ -26,6 +26,7 @@
#include FT_TRIGONOMETRY_H
#include FT_SYSTEM_H
#include FT_TRUETYPE_DRIVER_H
+#include FT_MULTIPLE_MASTERS_H
#include "ttinterp.h"
#include "tterrors.h"
@@ -782,7 +783,7 @@
/* INS_$8F */ PACK( 0, 0 ),
/* INS_$90 */ PACK( 0, 0 ),
- /* INS_$91 */ PACK( 0, 0 ),
+ /* GETVAR */ PACK( 0, 0 ), /* will be handled specially */
/* INS_$92 */ PACK( 0, 0 ),
/* INS_$93 */ PACK( 0, 0 ),
/* INS_$94 */ PACK( 0, 0 ),
@@ -1065,7 +1066,11 @@
"7 INS_$8F",
"7 INS_$90",
+#ifdef TT_CONFIG_OPTION_GX_VAR_SUPPORT
+ "6 GETVAR",
+#else
"7 INS_$91",
+#endif
"7 INS_$92",
"7 INS_$93",
"7 INS_$94",
@@ -7237,7 +7242,18 @@
if ( ( args[0] & 4 ) != 0 && exc->tt_metrics.stretched )
K |= 1 << 9;
+#ifdef TT_CONFIG_OPTION_GX_VAR_SUPPORT
/********************************/
+ /* VARIATION GLYPH */
+ /* Selector Bit: 3 */
+ /* Return Bit(s): 10 */
+ /* */
+ /* XXX: UNDOCUMENTED! */
+ if ( (args[0] & 8 ) != 0 && exc->face->blend )
+ K |= 1 << 10;
+#endif
+
+ /********************************/
/* BI-LEVEL HINTING AND */
/* GRAYSCALE RENDERING */
/* Selector Bit: 5 */
@@ -7379,7 +7395,42 @@
}
+#ifdef TT_CONFIG_OPTION_GX_VAR_SUPPORT
+
+ /*************************************************************************/
+ /* */
+ /* GETVARIATION[]: get normalized variation (blend) coordinates */
+ /* Opcode range: 0x24 */
+ /* Stack: --> f2.14... */
+ /* */
+ /* XXX: UNDOCUMENTED! There is no documentation from Apple for this */
+ /* bytecode instruction. */
+ /* */
static void
+ Ins_GETVARIATION( TT_ExecContext exc,
+ FT_Long* args )
+ {+ FT_UInt num_axes = exc->face->blend->num_axis;
+ FT_Fixed* coords = exc->face->blend->normalizedcoords;
+
+ FT_UInt i;
+
+
+ if ( BOUNDS( num_axes, exc->stackSize + 1 - exc->top ) )
+ {+ exc->error = FT_THROW( Stack_Overflow );
+ return;
+ }
+
+ for ( i = 0; i < num_axes; i++ )
+ args[i] = coords[i] >> 2; /* convert 16.16 to 2.14 format */
+ }
+
+#endif /* TT_CONFIG_OPTION_GX_VAR_SUPPORT */
+
+
+
+ static void
Ins_UNKNOWN( TT_ExecContext exc )
{TT_DefRecord* def = exc->IDefs;
@@ -7565,8 +7616,22 @@
exc->args = 0;
}
- exc->new_top = exc->args + ( Pop_Push_Count[exc->opcode] & 15 );
+#ifdef TT_CONFIG_OPTION_GX_VAR_SUPPORT
+ if ( exc->opcode == 0x91 )
+ {+ /* this is very special: GETVARIATION returns */
+ /* a variable number of arguments */
+ /* it is the job of the application to `activate' GX handling, */
+ /* this is, calling any of the GX API functions on the current */
+ /* font to select a variation instance */
+ if ( exc->face->blend )
+ exc->new_top = exc->args + exc->face->blend->num_axis;
+ }
+ else
+#endif
+ exc->new_top = exc->args + ( Pop_Push_Count[exc->opcode] & 15 );
+
/* `new_top' is the new top of the stack, after the instruction's */
/* execution. `top' will be set to `new_top' after the `switch' */
/* statement. */
@@ -8113,6 +8178,18 @@
case 0x8F:
Ins_UNKNOWN( exc );
break;
+
+#ifdef TT_CONFIG_OPTION_GX_VAR_SUPPORT
+ case 0x91:
+ /* it is the job of the application to `activate' GX handling, */
+ /* this is, calling any of the GX API functions on the current */
+ /* font to select a variation instance */
+ if ( exc->face->blend )
+ Ins_GETVARIATION( exc, args );
+ else
+ Ins_UNKNOWN( exc );
+ break;
+#endif
default:
if ( opcode >= 0xE0 )