Double Combining Marks

Classes.fea

##### Space #####
## Horizontal Classes
#@H1 = [$[layer0.width > 0 AND layer0.width <= $classH1Max]];
@H1 = [$[layer0.width > 0 AND layer0.width <= 432]];
#@H3 = [$[layer0.width >= $classH3Min]];
@H3 = [$[layer0.width >= 780]];

## Vertical Classes
##
## -- 5 (ascender)
## -- 4 (upper cap height)
## -- 3 (lower cap height)
## -- 2 (upper mean line)
## -- 1 (lower mean line)
## -- 0 (descender)
##
## (012345) X = occupied, ? = occupied/empty, _ = empty
##
## (????X)
#@V5 = [$[layer0.maxY > $classV4Max]];
@V5 = [$[layer0.maxY > 804]];
## (???X__)
#@V3 = [$[layer0.maxY > $classV2Max AND layer0.maxY <= $classV3Max]];
@V3 = [$[layer0.maxY > 564 AND layer0.maxY <= 660]];
## (??X___)
#@V2 = [$[layer0.maxY <= $classV2Max AND layer0.maxY > 0]];
@V2 = [$[layer0.maxY <= 564 AND layer0.maxY > 0]];
## (X?????)
#@V0 = [$[layer0.minY <= $classV0Max]];
@V0 = [$[layer0.minY <= -60]];

kern.fea

lookup kern_combining_double_mark_vertical_top {
	lookupflag UseMarkFilteringSet @TopDoubleMark;
	
	pos @V5 @TopDoubleMark' <0 $doubleMarkTopV5 0 0>;
	pos     @TopDoubleMark' <0 $doubleMarkTopV5 0 0> @V5;
	
	pos @V2 @TopDoubleMark' <0 $doubleMarkTopV3 0 0> @V3;
	pos @V3 @TopDoubleMark' <0 $doubleMarkTopV3 0 0> @V2;
	pos @V3 @TopDoubleMark' <0 $doubleMarkTopV3 0 0> @V3;
	
	pos @V2 @TopDoubleMark' <0 $doubleMarkTopV2 0 0> @V2;
} kern_combining_double_mark_vertical_top;

lookup kern_combining_double_mark_vertical_bottom {
	lookupflag UseMarkFilteringSet @BottomDoubleMark;
	
	pos @V0 @BottomDoubleMark' <0 $doubleMarkBottomV0 0 0>;
	pos     @BottomDoubleMark' <0 $doubleMarkBottomV0 0 0> @V0;
} kern_combining_double_mark_vertical_bottom;

# Separate top and bottom lookups so that cases with top and bottom double marks are also handled.
# The horizontal shift is the same for top and bottom marks, thus the feature code is the same and only the mark filtering set differs.
lookup kern_combining_double_mark_horizontal_top {
	lookupflag UseMarkFilteringSet @TopDoubleMark;
	
	pos        @H1 @DoubleMark' <$doubleMarkShift13 0 0 0> @H3;
	pos        @H3 @DoubleMark' <${doubleMarkShift13*-1} 0 0 0> @H1;
	
	ignore pos @H3 @DoubleMark' @H3;
	pos            @DoubleMark' <$doubleMarkShift23 0 0 0> @H3;
	pos        @H3 @DoubleMark' <${doubleMarkShift23*-1} 0 0 0>;
	
	ignore pos @H1 @DoubleMark' @H1;
	pos        @H1 @DoubleMark' <$doubleMarkShift12 0 0 0>;
	pos            @DoubleMark' <${doubleMarkShift12*-1} 0 0 0> @H1;
} kern_combining_double_mark_horizontal_top;

lookup kern_combining_double_mark_horizontal_bottom {
	lookupflag UseMarkFilteringSet @BottomDoubleMark;
	
	pos        @H1 @DoubleMark' <$doubleMarkShift13 0 0 0> @H3;
	pos        @H3 @DoubleMark' <${doubleMarkShift13*-1} 0 0 0> @H1;
	
	ignore pos @H3 @DoubleMark' @H3;
	pos            @DoubleMark' <$doubleMarkShift23 0 0 0> @H3;
	pos        @H3 @DoubleMark' <${doubleMarkShift23*-1} 0 0 0>;
	
	ignore pos @H1 @DoubleMark' @H1;
	pos        @H1 @DoubleMark' <$doubleMarkShift12 0 0 0>;
	pos            @DoubleMark' <${doubleMarkShift12*-1} 0 0 0> @H1;
} kern_combining_double_mark_horizontal_bottom;