@@ -1830,6 +1830,7 @@ def set_names_and_parse_actions():
18301830| p .underset
18311831| p .sqrt
18321832| p .overline
1833+ | p .auto_delim
18331834 )
18341835
18351836p .simple <<= (
@@ -2206,6 +2207,16 @@ def subsuper(self, s, loc, toks):
22062207result = Hlist ([vlist ])
22072208return [result ]
22082209
2210+ # Set the minimum shifts for the superscript and subscript.
2211+ constants = _get_font_constant_set (state )
2212+ if isinstance (nucleus ,Char ):
2213+ shift_up = 0
2214+ shift_down = 0
2215+ else :
2216+ # TODO Optimise and reduce line length.
2217+ shift_up = nucleus .height - constants .subdrop * xHeight * SHRINK_FACTOR
2218+ shift_down = nucleus .depth + constants .subdrop * xHeight * SHRINK_FACTOR
2219+
22092220# We remove kerning on the last character for consistency (otherwise
22102221# it will compute kerning based on non-shrunk characters and may put
22112222# them too close together when superscripted)
@@ -2232,7 +2243,6 @@ def subsuper(self, s, loc, toks):
22322243nucleus = Hlist ([nucleus ])
22332244
22342245# Handle regular sub/superscripts
2235- constants = _get_font_constant_set (state )
22362246lc_height = last_char .height
22372247lc_baseline = 0
22382248if self .is_dropsub (last_char ):
@@ -2260,7 +2270,12 @@ def subsuper(self, s, loc, toks):
22602270if self .is_dropsub (last_char ):
22612271shift_down = lc_baseline + constants .subdrop * xHeight
22622272else :
2263- shift_down = constants .sub1 * xHeight
2273+ # TODO Optimise.
2274+ if shift_down < constants .sub1 * xHeight :
2275+ shift_down = constants .sub1 * xHeight
2276+ clr = x .height - xHeight * 4 / 5
2277+ if shift_down < clr :
2278+ shift_down = clr
22642279x .shift_amount = shift_down
22652280else :
22662281x = Hlist ([Kern (superkern ),super ])