Single-font implementation

The preceding chapters treat one writing system each, but the fonts in common use do not: they cover the whole Mongolian block, and with it Hudum, Todo, Sibe, and Manchu together with their Ali Gali extensions. Such a font is a single-font implementation: it integrates several writing systems into one, as Structure anticipates. Because the block shares characters between its writing systems, the font must decide which written unit to show for a shared letter at a joining position wherever they disagree. L2/26-207 reviews the disagreements, which fall into three kinds.

Different letterforms. The same written unit may be drawn differently: the final form of the letter m (U+182E) has a small tail in Hudum and a large one in Sibe and Manchu. The written unit is the same and only the design differs, so the font keeps each design and selects it with the OpenType locl feature under the language system tag of the writing system (MNG, TOD, SIB, MCH).

Different FVS allocations. The writing systems do not always agree on which FVS a letter uses. The letter b (U+182A), shared by Hudum, Sibe, and Manchu, selects its final form with FVS1 in Hudum, while for Sibe and Manchu the sequence U+182A U+180B is invalid and renders an error form. A writing system and its Ali Gali are declared in one national standard, so a sequence is judged valid by that standard alone: valid in Hudum Ali Gali means valid in Hudum.

Different default forms. The writing systems may differ even in the default written unit at a position. U+188A MONGOLIAN LETTER ALI GALI NGA serves both Hudum Ali Gali and Todo Ali Gali: word-finally Hudum Ali Gali has an actual final form, while Todo Ali Gali, having none, renders the final of the Todo letter ang (U+184A). No tag separates them—the Ali Gali writing systems have no language system tags, and tags for Sanskrit or Tibetan, which they transcribe, would not help. A user may therefore meet the actual form of another writing system, which is for that user only a fabricated form derived from another position or writing system—as when a Manchu Ali Gali form appears to users of Sibe and Manchu, who would expect a form derived from the medial.

Implementing a single font. The letterform differences are served per writing system, as above; the FVS allocations and the default forms are not, so the font settles them by treating the writing systems as one. At each joining position it shows a single written unit, whatever the writing system of the text. An actual form is one a writing system genuinely writes at the position; a fabricated form is one derived from another position or writing system where the writing system has no form of its own. Consulting the writing systems in the order in which they are integrated—Hudum, Todo, Sibe, Manchu, each Ali Gali after its base—an actual form outranks a fabricated one, and an earlier writing system outranks a later. The unit shown is the actual form of the earliest writing system that has one, or, failing that, the fabricated form of the earliest that supplies one: the font shows the forms that exist and invents none. Whether a variation sequence is valid, and which FVS allocation applies, is decided by the higher-level protocol that shapes the text—the application, or the shaping engine that implements this document—which knows the writing system of the text.

Written units of all writing systems

Each position shows one shape.

ID	Variants				Ligated Variants
	isol	init	medi	fina	init	medi	fina
A	MNG MNGx TOD TODx SIB MCH MCHx 	MNG MNGx TOD TODx SIB MCH MCHx 	MNG MNGx TOD TODx SIB MCH MCHx 	MNG MNGx TOD TODx SIB MCH MCHx 			
A2		MCHx 
Aa	MNG MNGx 			MNG MNGx TOD TODx SIB MCH MCHx 			
Ah			SIB MCH MCHx 	SIB MCH MCHx 		
Ai			SIB MCH MCHx 	SIB MCH MCHx 
At				SIB MCH MCHx 			
Aw				MCHx 
B		MNG MNGx TOD TODx SIB MCH MCHx 	MNG MNGx TOD TODx SIB MCH MCHx 	MNG MNGx SIB MCH MCHx 	 	 
B2				MNG MNGx TOD TODx 
Bc		MCHx 	MCHx 		 	 
Bg		MNGx MCHx 	MNGx MCHx 	MNGx 	 	 
Bh		TODx 	TODx 		 	 
C		MNG MNGx TODx 	MNG MNGx TODx 	MNG MNGx 
Cc		SIB MCH MCHx 	SIB MCH MCHx 
Ch		MNG MNGx TOD TODx SIB MCH MCHx 	MNG MNGx TOD TODx SIB MCH MCHx 	MNG MNGx TOD TODx MCHx 
Cp		TOD TODx 	TOD TODx 	TOD TODx 
Cr		MNG 
Cr2		MNGx TODx 	MNGx TODx 
Cs		SIB MCH MCHx 	SIB MCH MCHx 
Ct		MCHx 	MCHx 
Cx				
D		MNG 	MNG SIB MCH MCHx 	MNG 
Db			SIB MCH MCHx 
Dd			MNG SIB MCH MCHx 	MNG SIB MCH MCHx 
Dh			SIB MCH MCHx 
Dp		TOD TODx 	TOD TODx 	TOD TODx 
Dq		MNGx 	MNGx 	MNGx 
Dr		MCHx 	MCHx 	MCHx 
Ds		MNGx TODx 	MNGx TODx 	MNGx TODx 
Dt		MCHx 	SIB MCH MCHx 
Dv		MNGx TODx 	MNGx TODx 	MNGx 
Dw			MCHx 
Dx			MCHx 
Dy		MCHx 	MCHx 
Dz			
E			TOD TODx 	TOD TODx 			
F		MNG 	MNG 	MNG 	 	 
G		MNG MNGx TOD TODx SIB MCH MCHx 	MNG MNGx TOD TODx SIB MCH MCHx 	MNG MNGx MCH MCHx 	 	 
G2				TOD TODx 
G3				SIB 
G4				MNGx MCH MCHx 
Gc		SIB MCH MCHx 	SIB MCH MCHx 		 	 
Gh		SIB MCH MCHx 	SIB MCH MCHx 		 	 
Gp		TOD 	TOD 		 	 
Gx		MNG MCH MCHx 	MNG MCH MCHx 	MCH MCHx 	 	 
H		MNG SIB MCH MCHx 	MNG SIB MCH MCHx 	MNG 
Hb		TOD TODx 	TOD TODx 
Hc		SIB MCH MCHx 	SIB MCH MCHx 
Hh		SIB MCH MCHx 	SIB MCH MCHx 		
Hh2			MCHx 			
Hp			TOD TODx 	TOD TODx 
Hr			MNG MNGx TOD TODx 	MNG MNGx TOD TODx 
Hx		MNG 	MNG TOD MCH MCHx 	MNG 
Hx2		TOD 		MCH MCHx 
Hy		MCHx 	MCHx 		
Hy2			MCHx 			
I	MNG SIB MCH 	MNG MNGx TOD TODx SIB MCH MCHx 	MNG MNGx TOD TODx SIB MCH MCHx 	MNG SIB MCH MCHx 			
I4				MNGx 			
Ic		SIB MCH MCHx 	SIB 
Ih		MCHx 
Ip			TOD TODx 	TOD TODx 			
Iq		MCHx 
Ir				TODx 
It		MCHx 
Ix	MNG 
Iy				MCH MCHx 
J		MNGx TOD TODx 	MNG MNGx TOD TODx MCH MCHx 	MNG MNGx TOD TODx MCHx 
J2			SIB 
Jb		TOD 	TOD 	TOD 
Jc			MCH MCHx 	MCHx 
Jh			MCHx 
Jq			MCHx 
Jt			MCHx 	MCHx 
K		MNG MNGx TOD TODx 	MNG MNGx TOD TODx 	MNG TOD 	 	 
K2		MNG MNGx TODx SIB MCH MCHx 	MNG MNGx TODx SIB MCH MCHx 	MNG 	 	 
Kc		SIB MCH 	SIB MCH 		 	 
Kh		SIB MCH MCHx 	SIB MCH MCHx 	MCHx 	 	 
Kp		TOD 	TOD 	TOD 	 	 
L		MNG MNGx TOD TODx SIB MCH MCHx 	MNG MNGx TOD TODx SIB MCH MCHx 	MNG MNGx TOD TODx SIB MCH MCHx 		
L2		MCHx 
Lc		MCHx 	MCHx 
Lv			TOD TODx 	TOD TODx 
M		MNG MNGx TOD TODx SIB MCH MCHx 	MNG MNGx TOD TODx SIB MCH MCHx 	MNG 		
M2				MNGx TOD TODx 
M3				SIB MCH MCHx 
N		MNG MNGx TOD TODx SIB MCH MCHx 	MNG MNGx TOD TODx SIB MCH MCHx 	MNG SIB MCH MCHx 
N2		TOD 
Nb		MCHx 	MCHx 
Ni			SIB MCH MCHx 
Nx			SIB MCHx 	SIB MCHx 
Ny		MNGx TOD TODx 	MNGx TOD TODx 	MNGx 
O		MNG 	MNG MNGx TOD TODx SIB MCH MCHx 	MNG MNGx TOD TODx SIB MCH MCHx 			
Ob			TOD TODx 	TOD TODx 			
Oh			SIB MCH MCHx 	SIB MCH MCHx 			
Op			TOD 	TOD 			
Ot			TOD 	TOD 			
P		MNG 	MNG 	MNG 	 	 
Pb		SIB MCH MCHx 	SIB MCH MCHx 		 	 
Pg		MNGx 	MNGx 		 	 
Ph		TODx 	TODx 		 	 
Pp		TOD 	TOD 	TOD 	 	 
Q		MNGx TODx 	MNGx TODx 
R		MNG MNGx TOD TODx SIB MCH MCHx 	MNG MNGx TOD TODx SIB MCH MCHx 	MNG MNGx TOD TODx SIB 
R2				MCH MCHx 
R3		MCHx 	MCHx 
Rh		MNG 	MNG 	MNG 
Rh2		MNGx 	MNGx 
Rr		SIB MCH 	SIB MCH 
Rz		TODx 	TODx 
S		MNG MNGx TOD TODx SIB MCH MCHx 	MNG MNGx TOD TODx SIB MCH MCHx 	MNG MNGx TOD TODx SIB MCH MCHx 
S3				MCHx 
Sc		MCHx 	MCHx 
Sh		MNG MNGx TOD TODx 	MNG MNGx TOD TODx 	MNG MNGx TOD TODx 
Sp		SIB MCH MCHx 	SIB MCH MCHx 	SIB MCH MCHx 
St		MCHx 	MCHx 
St2		MCHx 	MCHx 
Sx		MNGx TODx 	MNGx TODx 	MNGx 
Sx2		MCHx 	MCHx 	MCHx 
Sz				MNG 
T		MNG SIB MCH MCHx 	MNG 	MNG 
Tb		SIB MCH MCHx 
Th		SIB MCH MCHx 
Tp		MNGx TOD TODx 	MNGx TOD TODx 	MNGx TOD TODx 
Ts		MCHx 
Tt		SIB MCH MCHx 
Tx		MCHx 
U	MNG 			MNG MNGx TOD TODx SIB MCH MCHx 
Ue				MNG MNGx SIB MCH MCHx 			
Uh				SIB MCH MCHx 
Up				TOD 
Ux	MNG 
V		SIB MCH 	SIB MCH 
Vi				MNGx 
W		MNG MNGx TOD SIB MCH MCHx 	MNG MNGx TOD SIB MCH MCHx 	MNG MNGx TOD 			
Wb		TOD TODx 	TOD TODx 	TOD TODx 
Wc		MCHx 	MCHx 			
Wd		MCHx 	MCHx 			
Wn		MNGx TODx MCHx 	MNGx TODx MCHx 	MNGx MCHx 
Wp			MNGx 	TODx 
Y		MNG SIB MCH MCHx 	MNG SIB MCH MCHx 
Yp			TOD TODx 	TODx 
Z		MNG MNGx 	MNG MNGx 	MNG MNGx 
Zc		MNGx 	MNGx 	MNGx 
Zr		MNG 
Zr2		MNGx TODx 	MNGx TODx 	MNGx 
Zs		SIB MCH MCHx 	SIB MCH MCHx 
Zs2		SIB 	SIB 			
Zt		MCHx 	MCHx 
Zz		TOD TODx 	TOD TODx 	TOD TODx 
Zz2		TOD TODx 	TOD TODx 	TOD TODx 
Zz3		MNGx TODx 	MNGx TODx 	MNGx 

Characters of all writing systems

Each character shows its variants by joining position.

Letter	FVS	Variants
		isol	init	medi	fina
1807 ᠇	-	SIB MCH (MCHx)  → medi	MCHx (SIB MCH)  A2	SIB MCH MCHx  A	SIB MCH MCHx  → medi
1820 ᠠ	-			MNG MNGx TOD TODx SIB MCH MCHx  A
	1	MNG MNGx TOD TODx  A	MNG MNGx  A	MNG MNGx TOD TODx  A A	MNG MNGx TOD TODx SIB MCH MCHx  Aa
	2	MNG MNGx  Aa	MNG MNGx TOD TODx SIB MCH MCHx  A A		MNG MNGx TOD TODx SIB MCH MCHx  A
	3	MNG MNGx TOD TODx SIB MCH MCHx  A A
1821 ᠡ	-		MNG  A	MNG  A
	1	MNG  Aa	MNG  A A		MNG  Aa
	2	MNG  A			MNG  A
1822 ᠢ	-				MNG  I
	1	MNG  I	MNG  I	MNG  A I
	2	MNG  Ix	MNG  A I	MNG  I I
	3	MNG  A I		MNG  I
1823 ᠣ	-	MNG MNGx SIB MCH MCHx  A O	MNG MNGx SIB MCH MCHx  A O	MNG MNGx SIB MCH MCHx  O
	1			MNG  A O	MNG MNGx SIB MCH MCHx  O
	2				MNG MNGx SIB MCH MCHx  U
1824 ᠤ	-			MNG  O
	1	MNG  U	MNG  O	MNG  A O	MNG  O
	2	MNG  Ux	MNG  A O		MNG  U
	3	MNG  A O
1825 ᠥ	-	MNG  A Ue	MNG  A O I
	1	MNG  A U		MNG  O I	MNG  Ue
	2			MNG  A O I	MNG  O
	3			MNG  O	MNG  U
1826 ᠦ	-	MNG MNGx  A Ue
	1	MNG MNGx  A U	MNG  O	MNG MNGx  O I	MNG  Ue
	2	MNG  U	MNG MNGx  A O I	MNG  A O I	MNG MNGx  O
	3	MNG  Ux		MNG MNGx  O	MNG MNGx  U
1827 ᠧ	-	MNG MNGx  A W	MNG MNGx  A W	MNG MNGx  W	MNG MNGx  W
1828 ᠨ	-	MNG MNGx TOD TODx SIB MCH MCHx  → init	MNG MNGx TOD TODx SIB MCH MCHx  N
	1	MNG  → init 1	MNG MCHx  A	MNG MNGx TOD TODx SIB MCH MCHx  N	MNG SIB MCH MCHx  N
	2	TOD  → init 2	TOD  N2	MNG MNGx TOD TODx SIB MCH MCHx  A	MNG MNGx TOD TODx SIB MCH MCHx  A
	3			MCHx  Nx	MCHx  Nx
1829 ᠩ	-	MNG MNGx MCH MCHx  → medi	MNG MNGx MCH MCHx  → medi	MNG MNGx MCH MCHx  A G	MNG MNGx MCH MCHx  A G
182A ᠪ	-	MNG MNGx SIB MCH MCHx  → init	MNG MNGx SIB MCH MCHx  B	MNG MNGx SIB MCH MCHx  B	MNG MNGx SIB MCH MCHx  B
	1				MNG MNGx  B2
182B ᠫ	-	MNG  → init	MNG  P	MNG  P	MNG  P
182C ᠬ	-	MNG  → init 3			MNG  H
	1	MNG  → init 1	MNG  Hx	MNG  Hx	MNG  Hx
	2	MNG  → init 2	MNG  G	MNG  G
	3		MNG  H	MNG  H
	4	MNG  → init 4	MNG  Gx	MNG  Gx
182D ᠭ	-	MNG  → init 3
	1	MNG  → init 1	MNG  H	MNG  Hx	MNG  H
	2	MNG  → init 2	MNG  G	MNG  G	MNG  G
	3		MNG  Hx	MNG  H	MNG  Hx
	4	MNG  → init 4	MNG  Gx	MNG  Gx
182E ᠮ	-	MNG SIB MCH MCHx  → init	MNG SIB MCH MCHx  M	MNG SIB MCH MCHx  M	MNG  M SIB MCH MCHx  M3
182F ᠯ	-	MNG MNGx TOD TODx SIB MCH MCHx  → init	MNG MNGx TOD TODx SIB MCH MCHx  L	MNG MNGx TOD TODx SIB MCH MCHx  L	MNG MNGx TOD TODx SIB MCH MCHx  L
	1	MCHx  → init 1	MCHx  L2
1830 ᠰ	-	MNG MNGx TOD TODx SIB MCH MCHx  → init	MNG MNGx TOD TODx SIB MCH MCHx  S	MNG MNGx TOD TODx SIB MCH MCHx  S	MNG MNGx TOD TODx SIB MCH MCHx  S
	1				MNG  Sz
	2				MCHx  S3
1831 ᠱ	-	MNG MNGx TOD TODx  → init 2			MNG MNGx TOD TODx  Sh
	1	MNG  → init 1	MNG  S	MNG  S
	2		MNG MNGx TOD TODx  Sh	MNG MNGx TOD TODx  Sh
1832 ᠲ	-	MNG  → init	MNG  T		MNG  T
	1			MNG  T
	2			MNG  D
1833 ᠳ	-	MNG  → init 1			MNG  Dd
	1	MNG  → init 2	MNG  D	MNG  D	MNG  D
	2		MNG  T	MNG  Dd
1834 ᠴ	-	MNG MNGx TOD TODx SIB MCH MCHx  → init	MNG MNGx TOD TODx SIB MCH MCHx  Ch	MNG MNGx TOD TODx SIB MCH MCHx  Ch	MNG MNGx TOD TODx MCHx (SIB MCH)  Ch
1835 ᠵ	-	MNG MCH MCHx  → init	MNG MCH MCHx  I	MNG MCH MCHx  J	MNG MCHx (MCH)  J
	1	MNG  I			MNG  I
1836 ᠶ	-	MNG SIB MCH MCHx  → init 2			MNG (SIB MCH MCHx)  I
	1	MNG  → init 1	MNG  I	MNG  I
	2		MNG SIB MCH MCHx  Y	MNG  I I
	3			MNG SIB MCH MCHx  Y
1837 ᠷ	-	MNG MNGx TOD TODx SIB  → init	MNG MNGx TOD TODx SIB  R	MNG MNGx TOD TODx SIB  R	MNG MNGx TOD TODx SIB  R
1838 ᠸ	-	MNG MNGx TOD SIB MCH MCHx  → init	MNG MNGx TOD SIB MCH MCHx  W	MNG MNGx TOD SIB MCH MCHx  W	MNG MNGx TOD (SIB MCH MCHx)  W
	1			MNG  O	MNG  U
1839 ᠹ	-	MNG  → init	MNG  F	MNG  F	MNG  F
183A ᠺ	-	MNG MNGx TODx SIB MCH MCHx  → init	MNG MNGx TODx SIB MCH MCHx  K2	MNG MNGx TODx SIB MCH MCHx  K2	MNG (MNGx TODx SIB MCH MCHx)  K2
	1				MNGx  K2 Vi
183B ᠻ	-	MNG MNGx TODx  → init	MNG MNGx TODx  K	MNG MNGx TODx  K	MNG (MNGx TODx)  K
183C ᠼ	-	MNG MNGx TODx  → init	MNG MNGx TODx  C	MNG MNGx TODx  C	MNG MNGx (TODx)  C
183D ᠽ	-	MNG MNGx  → init	MNG MNGx  Z	MNG MNGx  Z	MNG MNGx  Z
183E ᠾ	-	MNG MNGx TODx  → init	MNG MNGx TODx  A Hr	MNG MNGx TODx  Hr	MNG MNGx (TODx)  Hr
183F ᠿ	-	MNG  → init	MNG  Rh	MNG  Rh	MNG  Rh
1840 ᡀ	-	MNG MNGx TOD TODx  → init	MNG MNGx TOD TODx  L Hr	MNG MNGx TOD TODx  L Hr	MNG MNGx TOD TODx  → medi
1841 ᡁ	-	MNG  → init	MNG  Zr	MNG  → init	MNG  → init
1842 ᡂ	-	MNG  → init	MNG  Cr	MNG  → init	MNG  → init
1843 ᡃ	-	TOD TODx  → medi	TOD TODx  → medi	TOD TODx  Lv	TOD TODx  Lv
1844 ᡄ	-	TOD TODx  A E	TOD TODx  A E	TOD TODx  E	TOD TODx  E
	1			TOD TODx  A E
1845 ᡅ	-	TOD TODx  A Ip	TOD TODx  A Ip		TOD TODx  Ip
	1		TOD  A I	TOD TODx  A Ip
	2			TOD TODx  Ip
	3			TOD  I
1846 ᡆ	-	TOD TODx  A Ob	TOD TODx  A Ob	TOD TODx  Ob	TOD TODx  Ob
	1			TOD TODx  A Ob
1847 ᡇ	-	TOD  A Up	TOD  A Op
	1	TOD  A Op		TOD  A Op	TOD  U
	2			TOD  O	TOD  Op
	3			TOD  Op	TOD  Up
1848 ᡈ	-	TOD  A Ot	TOD  A Ot	TOD  Ot	TOD  Ot
	2			TOD  A Ot
1849 ᡉ	-	TOD TODx  A U	TOD TODx  A O	TOD TODx  O
	1	TOD TODx  A O		TOD TODx  A O	TOD TODx  O
	2				TOD TODx  U
184A ᡊ	-	TOD TODx  → medi	TOD TODx  → medi	TOD TODx  A G	TOD TODx  A G2
184B ᡋ	-	TOD TODx  → init	TOD TODx  B	TOD TODx  B	TOD TODx  B2
184C ᡌ	-	TOD  → init	TOD  Pp	TOD  Pp	TOD (TODx)  Pp
	1	TODx  → init 1	TODx  Ph	TODx  Ph
184D ᡍ	-	TOD  → init 2			TOD  K
	1	TOD  → init 1	TOD  K	TOD  K
	2		TOD  Hx2	TOD  Hx
184E ᡎ	-	TOD TODx  → init 2			TOD TODx  Hp
	1	TOD TODx  → init 1	TOD TODx  G	TOD TODx  Hp
	2		TOD TODx  Hb	TOD TODx  G
	3			TOD TODx  Hb
184F ᡏ	-	MNGx TOD TODx  → init	MNGx TOD TODx  M	MNGx TOD TODx  M	MNGx TOD TODx  M2
1850 ᡐ	-	MNGx TOD TODx  → init	MNGx TOD TODx  Tp	MNGx TOD TODx  Tp	MNGx TOD TODx  Tp
1851 ᡑ	-	TOD TODx  → init	TOD TODx  Dp	TOD TODx  Dp	TOD TODx  Dp
1852 ᡒ	-	TOD  → init	TOD  Jb	TOD  Jb	TOD  Jb
1853 ᡓ	-	TOD TODx  → init	TOD TODx  Cp	TOD TODx  Cp	TOD TODx  Cp
1854 ᡔ	-	MNGx TOD TODx  → init	MNGx TOD TODx  J	MNGx TOD TODx  J	MNGx TOD TODx  J
1855 ᡕ	-	MNGx TOD TODx  → init	MNGx TOD TODx  I	MNGx TOD TODx  I	MNGx TOD TODx  → medi
1856 ᡖ	-	TOD TODx  → init	TOD TODx  Wb	TOD TODx  Wb	TOD TODx  Wb
1857 ᡗ	-	TOD  → init	TOD  Kp	TOD  Kp	TOD  Kp
1858 ᡘ	-	TOD  → init	TOD  Gp	TOD  Gp	TOD  → medi
1859 ᡙ	-	MNGx TOD TODx  → init	MNGx TOD TODx  A Hr	MNGx TOD TODx  A Hr	MNGx TOD TODx  A Hr
185A ᡚ	-	TOD  → init	TOD  B Yp	TOD  B Yp	TOD  → medi
185B ᡛ	-	MNGx TOD TODx  → init	MNGx TOD TODx  Ny	MNGx TOD TODx  Ny	MNGx (TOD TODx)  Ny
185C ᡜ	-	TOD TODx  → init	TOD TODx  Zz	TOD TODx  Zz	TOD TODx  Zz
	1	TOD TODx  → init 1	TOD TODx  Zz2	TOD TODx  Zz2	TOD TODx  Zz2
185D ᡝ	-	SIB MCH MCHx  A	SIB MCH MCHx  A Ni
	1			SIB MCH MCHx  A	SIB MCH MCHx  A
	2			SIB MCH MCHx  Ah	SIB MCH MCHx  At
	3				SIB MCH MCHx  Aa
	4				SIB MCH MCHx  Ah
185E ᡞ	-		SIB  A I		SIB  I
	1	SIB  I		SIB  A I
	2	SIB  A I		SIB  I
185F ᡟ	-	SIB MCH MCHx  → medi	SIB MCH MCHx  → medi	SIB MCH MCHx  Ai	SIB MCH MCHx  Ai
1860 ᡠ	-	SIB MCH MCHx  A Oh	SIB MCH MCHx  A Oh
	1			SIB MCH MCHx  O	SIB MCH MCHx  U
	2			SIB MCH MCHx  Oh	SIB MCH MCHx  Oh
	3				SIB MCH MCHx  O
	4				SIB MCH MCHx  Uh
1861 ᡡ	-	SIB MCH MCHx  A Ue	SIB MCH MCHx  A O I	SIB MCH MCHx  O I	SIB MCH MCHx  Ue
1862 ᡢ	-	SIB  → medi	SIB  → medi	SIB  A G	SIB  A G3
1863 ᡣ	-	SIB  → init 3			SIB  Nx
	1	SIB  → init 1	SIB  G	SIB  Nx
	2			SIB  G
	3		SIB  H	SIB  H
1864 ᡤ	-	SIB MCH MCHx  → init 2			SIB MCH MCHx  → medi 2
	1	SIB MCH MCHx  → init 1	SIB MCH MCHx  Gh	SIB MCH MCHx  Gh
	2		SIB MCH MCHx  Hh	SIB MCH MCHx  Hh
	3			MCHx  Hh2
1865 ᡥ	-	SIB MCH MCHx  → init 2			SIB MCH MCHx  → medi 2
	1	SIB MCH MCHx  → init 1	SIB MCH MCHx  Gc	SIB MCH MCHx  Gc
	2		SIB MCH MCHx  Hc	SIB MCH MCHx  Hc
1866 ᡦ	-	SIB MCH MCHx  → init	SIB MCH MCHx  Pb	SIB MCH MCHx  Pb	SIB MCH MCHx  → medi
1867 ᡧ	-	SIB MCH MCHx  → init	SIB MCH MCHx  Sp	SIB MCH MCHx  Sp	SIB MCH MCHx  Sp
1868 ᡨ	-	SIB MCH MCHx  → init 2			SIB MCH MCHx  Dd
	1	SIB MCH MCHx  → init 1	SIB MCH MCHx  Tb	SIB MCH MCHx  Db
	2		SIB MCH MCHx  T	SIB MCH MCHx  Dd
	3			SIB MCH MCHx  D
1869 ᡩ	-	SIB MCH MCHx  → init 2			SIB MCH MCHx  → medi 2
	1	SIB MCH MCHx  → init 1	SIB MCH MCHx  Tt	SIB MCH MCHx  Dt
	2	MCHx  → init 3	SIB MCH MCHx  Th	SIB MCH MCHx  Dh
	3		MCHx  Dt
186A ᡪ	-	SIB  → init	SIB  I	SIB  J2	SIB  → medi
186B ᡫ	-	SIB  → init	SIB  V	SIB  V	SIB  → medi
186C ᡬ	-	SIB MCH MCHx  → init	SIB MCH MCHx  Kh	SIB MCH MCHx  Kh	MCHx (SIB MCH)  Kh
186D ᡭ	-	SIB MCH  → init	SIB MCH  Kc	SIB MCH  Kc	SIB MCH  → medi
186E ᡮ	-	SIB MCH MCHx  → init	SIB MCH MCHx  Cs	SIB MCH MCHx  Cs	SIB MCH MCHx  → medi
186F ᡯ	-	SIB MCH MCHx  → init 2			SIB MCH MCHx  → medi 2
	1		SIB  Zs2	SIB  Zs2
	2		SIB MCH MCHx  Zs	SIB MCH MCHx  Zs
1870 ᡰ	-	SIB MCH  → init	SIB MCH  Rr	SIB MCH  Rr	SIB MCH  → medi
1871 ᡱ	-	SIB MCH MCHx  → init	SIB MCH MCHx  Cc	SIB MCH MCHx  Cc	SIB MCH MCHx  → medi
1872 ᡲ	-	SIB  → init	SIB  Ic	SIB  Ic	SIB  → medi
1873 ᡳ	-		MCH MCHx  A I
	1	MCH  I		MCH MCHx  I I	MCH MCHx  Iy
	2	MCH MCHx  A I		MCH MCHx  A I	MCH MCHx  I
	3			MCH MCHx  I
1874 ᡴ	-	MCH MCHx  → init 3
	1	MCH MCHx  → init 1	MCH MCHx  G	MCH MCHx  Hx	MCH MCHx  G4
	2	MCH MCHx  → init 2	MCH MCHx  Gx	MCH MCHx  G	MCH MCHx  Gx
	3		MCH MCHx  H	MCH MCHx  H	MCH MCHx  Hx2
	4			MCH MCHx  Gx
1875 ᡵ	-	MCH MCHx  → init	MCH MCHx  R	MCH MCHx  R	MCH MCHx  R2
	1	MCHx  → init 1	MCHx  R3	MCHx  R3
1876 ᡶ	-	MCH  → init 2			MCH  → medi 2
	1	MCH  → init 1	MCH  W	MCH  W
	2		MCH  V	MCH  V
1877 ᡷ	-	MCH MCHx  → init	MCH MCHx  Ic	MCH MCHx  Jc	MCHx (MCH)  Jc
1878 ᡸ	-	 → init	 Cx	 Cx	 Cx
1887 ᢇ	-	MCHx  A Aw	MCHx  A A	MCHx  A	MCHx  Aw
1888 ᢈ	-	MNGx  A I4	MNGx  A I	MNGx  I	MNGx  I4
1889 ᢉ	-	MNGx TODx  → init	MNGx TODx  G	MNGx TODx  G	MNGx (TODx)  G Vi
188A ᢊ	-	MNGx TODx  → init	MNGx TODx  N G	MNGx TODx  N G	MNGx (TODx)  N G4
188B ᢋ	-	MNGx  → init	MNGx  Zc	MNGx  Zc	MNGx  Zc
188C ᢌ	-	MNGx TODx  → init	MNGx TODx  Zr2	MNGx TODx  Zr2	MNGx (TODx)  Zr2
188D ᢍ	-	MNGx TODx  → init	MNGx TODx  Cr2	MNGx TODx  Cr2	MNGx TODx  → medi
188E ᢎ	-	MNGx TODx  → init	MNGx TODx  Ds	MNGx TODx  Ds	MNGx TODx  Ds
188F ᢏ	-	MNGx TODx MCHx  → init	MNGx TODx MCHx  Wn	MNGx TODx MCHx  Wn	MNGx MCHx (TODx)  Wn
1890 ᢐ	-	MNGx TODx  → init	MNGx TODx  Dv	MNGx TODx  Dv	MNGx (TODx)  Dv
1891 ᢑ	-	MNGx  → init	MNGx  Dq	MNGx  Dq	MNGx  Dq
1892 ᢒ	-	MNGx MCHx  → init	MNGx MCHx  Bg	MNGx MCHx  Bg	MNGx (TODx MCHx)  Bg
	1	TODx  → init 1	TODx  Bh	TODx  Bh
1893 ᢓ	-	MNGx  → init	MNGx  Pg	MNGx  Pg	MNGx  → medi
1894 ᢔ	-	MNGx TODx  → init	MNGx TODx  Sx	MNGx TODx  Sx	MNGx (TODx)  Sx
1895 ᢕ	-	MNGx  → init	MNGx  Rh2	MNGx  Rh2	MNGx  → medi
1896 ᢖ	-	MNGx TODx  → init	MNGx TODx  Zz3	MNGx TODx  Zz3	MNGx (TODx)  Zz3
1897 ᢗ	-	MNGx TODx  → init	MNGx TODx  Q	MNGx TODx  Q	MNGx TODx  → medi
1898 ᢘ	-	 → init	 Dz	 Dz	 → medi
1899 ᢙ	-	TODx  → init	TODx  Rz	TODx  Rz	TODx  → medi
189A ᢚ	-	MCHx  → init	MCHx  Hy		MCHx  → medi 2
	1			MCHx  Hy2
	2			MCHx  Hy
189B ᢛ	-	MCHx  → init	MCHx  Nb	MCHx  Nb	MCHx  → medi
189C ᢜ	-	MCHx  → init	MCHx  Ct	MCHx  Ct	MCHx  → medi
189D ᢝ	-	MCHx  → init	MCHx  Zt	MCHx  Zt	MCHx  → medi
189E ᢞ	-	MCHx  → init	MCHx  It	MCHx  Jt	MCHx  Jt
189F ᢟ	-	MCHx  → init	MCHx  Ih	MCHx  Jh	MCHx  → medi
18A0 ᢠ	-	MCHx  → init 2			MCHx  Dr
	1	MCHx  → init 1	MCHx  Dy	MCHx  Dy
	2		MCHx  Dr	MCHx  Dr
18A1 ᢡ	-	MCHx  → init 2			MCHx  → medi 2
	1	MCHx  → init 1	MCHx  Ts	MCHx  Dw
	2		MCHx  Tx	MCHx  Dx
18A2 ᢢ	-	MCHx  → init	MCHx  Sx2	MCHx  Sx2	MCHx  Sx2
18A3 ᢣ	-	MCHx  → init	MCHx  Iq	MCHx  Jq	MCHx  → medi
18A4 ᢤ	-	MCHx  → init	MCHx  St	MCHx  St	MCHx  → medi
	1	MCHx  → init 1	MCHx  St2	MCHx  St2
18A5 ᢥ	-	MCHx  → init	MCHx  Sc	MCHx  Sc	MCHx  → medi
18A6 ᢦ	-	MNGx (TODx)  → medi	MNGx (TODx)  → medi	MNGx (TODx)  Wp	TODx (MNGx)  Wp
18A7 ᢧ	-	TODx  → medi	TODx  → medi	TODx  Yp	TODx  Yp
	1				TODx  Ir
18A8 ᢨ	-	MCHx  → init	MCHx  Bc	MCHx  Bc	MCHx  → medi
	1	MCHx  → init 1	MCHx  Wd	MCHx  Wd
	2	MCHx  → init 2	MCHx  Wc	MCHx  Wc
18AA ᢪ	-	MCHx  → init	MCHx  Lc	MCHx  Lc	MCHx  → medi

Two characters lie at the edge of this document’s scope, and it specifies no detailed requirements for either:

U+1878 MONGOLIAN LETTER CHA WITH TWO DOTS. Used in Buryat Mongolian, proposed by Andrew West, Amgalan Zhamsoev and Viacheslav Zaytsev in WG2 N4781 and added in Unicode 14.0. Only its medial form is attested in the historical Buryat sources; its initial and final forms were also proposed, as fabricated glyphs.

U+1898 MONGOLIAN LETTER TODO ALI GALI TA. Used in no writing system, and perhaps coined by Quejingzhabu. In one scheme the Todo Ali Gali letter ta was analyzed as Dp, and the letter da shown the same way, so a stroke was added to tell da apart. All of its glyphs are fabricated.

The first concerns the specifications for Buryat Mongolian and, as WG2 N4781 indicates, goes beyond this document’s scope; the second appears in no Mongolian writing system, and the current Chinese national standard supports it only for compatibility.

Reference implementations

The fonts below each serve the whole Mongolian block, so each settles the ambiguity above, and the way it settles it is a reading of this model.

Mongolian Baiti (Monbaiti.ttf). Designed by Founder of Beijing and supplied with Windows since Vista, and with Office beside it, so it is the Mongolian font most users already have. Its script tags declare Mong and Latn.

Noto Sans Mongolian. The Noto project’s Mongolian family, designed by the Monotype design team under the SIL Open Font License, which makes its sources readable alongside this document: the UFO sources, the OpenType Layout features its build composes, and the FontBakery runs that check the result. A specimen and a glyph list are on Google Fonts. This document’s own reference implementation, mongfontbuilder, was developed alongside it—the test fonts of the Toolchain are its sources—so the two agree by construction on the block’s written units, and their disagreement is where this document is still open to question.

Both are single-font implementations rather than fonts of a single writing system, and the FVS allocation is the sharpest case: a font of the whole block cannot serve two writing systems that disagree on whether a sequence is valid, so both have had to choose—and this document says how.