texlive[72839] Build/source/texk/web2c: remove incorrect

[commits+karl at tug.org]

Revision: 72839
          https://tug.org/svn/texlive?view=revision&revision=72839
Author:   karl
Date:     2024-11-13 18:17:35 +0100 (Wed, 13 Nov 2024)
Log Message:
-----------
remove incorrect simplification of assignment to alpha

Modified Paths:
--------------
    trunk/Build/source/texk/web2c/ChangeLog
    trunk/Build/source/texk/web2c/NEWS
    trunk/Build/source/texk/web2c/mf.ch

Modified: trunk/Build/source/texk/web2c/ChangeLog
===================================================================
--- trunk/Build/source/texk/web2c/ChangeLog	2024-11-13 00:42:43 UTC (rev 72838)
+++ trunk/Build/source/texk/web2c/ChangeLog	2024-11-13 17:17:35 UTC (rev 72839)
@@ -1,3 +1,11 @@
+2024-11-13  Karl Berry  <karl at freefriends.org>
+
+	* mf.ch (Calculate integers $\alpha$...): comment out erroneous
+	change that "simplified" the assignment of alpha, resulting in a
+	few pen polygons being affected, but don't know if any extant
+	fonts are impacted. Report from Tim Stadelman,
+	https://tug.org/pipermail/tex-k/2021-August/003648.html.
+
 2024-10-20  TANAKA Takuji  <ttk at t-lab.opal.ne.jp>
 
 	* lib/texmfmp.c (maininit): Support ofm in {,e}upTeX.

Modified: trunk/Build/source/texk/web2c/NEWS
===================================================================
--- trunk/Build/source/texk/web2c/NEWS	2024-11-13 00:42:43 UTC (rev 72838)
+++ trunk/Build/source/texk/web2c/NEWS	2024-11-13 17:17:35 UTC (rev 72839)
@@ -1,6 +1,11 @@
 This file records noteworthy changes.  (Public domain.)
 See also */NEWS, */ChangeLog, etc.
 
+* mf: remove incorrect change of long standing in the Web2c mf.ch file,
+which affects calculation of a few pen polygons in a small way; we don't
+know if any extant fonts are impacted.
+
+

 2024 (for TeX Live 2024, 10 March 2024)
 
 * For all engines: if the --output-directory option is given, its value

Modified: trunk/Build/source/texk/web2c/mf.ch
===================================================================
--- trunk/Build/source/texk/web2c/mf.ch	2024-11-13 00:42:43 UTC (rev 72838)
+++ trunk/Build/source/texk/web2c/mf.ch	2024-11-13 17:17:35 UTC (rev 72839)
@@ -1108,25 +1108,35 @@
 else print(" offset");
 @z
 
-% [25.530] |make_fraction| and |take_fraction| arguments are too long for
-% some preprocessors, when they were defined as macros, just as in the
-% previous change.
- at x [25.530] l.11334
-  alpha:=take_fraction(take_fraction(major_axis,
-      make_fraction(gamma,beta)),n_cos)@|
-    -take_fraction(take_fraction(minor_axis,
-      make_fraction(delta,beta)),n_sin);
-  alpha:=(alpha+half_unit) div unity;
-  gamma:=pyth_add(take_fraction(major_axis,n_cos),
-    take_fraction(minor_axis,n_sin));
- at y
-  alpha := make_fraction (gamma, beta);
-  alpha := take_fraction (major_axis, alpha);
-  alpha := take_fraction (alpha, n_cos);
-  alpha := (alpha+half_unit) div unity;
-  gamma := take_fraction (minor_axis, n_sin);
-  gamma := pyth_add (take_fraction (major_axis, n_cos), gamma);
- at z
+% This change was erroneous; it omitted the second term of the
+% difference. This affects a few pen polygons in a small way,
+% but don't know if any extant fonts are impacted.
+% 
+% Hopefully by now, many years later, there's no problem
+% with the long arguments, but leaving the code here just in case.
+% Report from Tim Stadelman,
+% https://tug.org/pipermail/tex-k/2021-August/003648.html.
+% Applied 13 November 2024.
+% 
+%% |make_fraction| and |take_fraction| arguments are too long for
+%% some preprocessors, when they were defined as macros, just as in the
+%% previous change.
+%@x [25.530] l.11334
+%  alpha:=take_fraction(take_fraction(major_axis,
+%      make_fraction(gamma,beta)),n_cos)@|
+%    -take_fraction(take_fraction(minor_axis,
+%      make_fraction(delta,beta)),n_sin);
+%  alpha:=(alpha+half_unit) div unity;
+%  gamma:=pyth_add(take_fraction(major_axis,n_cos),
+%    take_fraction(minor_axis,n_sin));
+%@y
+%  alpha := make_fraction (gamma, beta);
+%  alpha := take_fraction (major_axis, alpha);
+%  alpha := take_fraction (alpha, n_cos);
+%  alpha := (alpha+half_unit) div unity;
+%  gamma := take_fraction (minor_axis, n_sin);
+%  gamma := pyth_add (take_fraction (major_axis, n_cos), gamma);
+%@z
 
 @x [26.556] l.11902 - Use halfp.
         begin cur_t:=half(cur_t+1); cur_tt:=half(cur_tt+1); return;