diff options
Diffstat (limited to 'metapost/context/base/mp-chem.mpiv')
| -rw-r--r-- | metapost/context/base/mp-chem.mpiv | 32 |
1 files changed, 24 insertions, 8 deletions
diff --git a/metapost/context/base/mp-chem.mpiv b/metapost/context/base/mp-chem.mpiv index a316a1a30..7ca40bbea 100644 --- a/metapost/context/base/mp-chem.mpiv +++ b/metapost/context/base/mp-chem.mpiv @@ -11,7 +11,8 @@ %C therefore copyrighted by \PRAGMA. See licen-en.pdf for %C details. -%D This module is incomplete and experimental. +%D This module is incomplete and experimental. Okay, it's not that bad but we do need +%D some disclaimer. % either consistent setting or not @@ -300,7 +301,6 @@ enddef ; chem_init_all ; % WHY does this not work unless defined and then called? - % Like most often in ConTeXt, we will trap but then silently ignore mistaken use, % unless of course the error be too harmful... @@ -529,6 +529,17 @@ vardef chem_set (suffix $) = % This is a fairly complicated optimization and ajustement. It took some % thinking to get right, so beware! + % And then even more time fixing a bug of a rotation +- half the symmetry + % angle of a structure depending on the scale and/or the font size + % (through chem_b_length). + + % first save the symmetry angle of the structure (as in chem_rot): + chem_num0 := if chem_stacked[$] : 3 else : 0 fi ; + chem_num9 := if chem_tetra[$] : 360 else : + abs(angle(point 0+chem_num0 of chem_b_path[$]) - + angle(point 1+chem_num0 of chem_b_path[$])) + fi ; + if (chem_adjacent<>0) and chem_star[P] and chem_star[$] : % nop chem_adjacent := 0 ; @@ -581,7 +592,8 @@ vardef chem_set (suffix $) = -((point (chem_adjacent-1) of chem_b_path[P]) chem_transformed(P)) ; fi % adjust the bond angles - chem_rotation := (chem_rotation + angle(chem_pair1)-angle(chem_pair3)) mod 360 ; + chem_num4 := (angle(chem_pair1)-angle(chem_pair3)) zmod chem_num9 ; + chem_rotation := chem_rotation + chem_num4 ; if not chem_star[$] : chem_pair4 := if chem_star[P] : @@ -666,7 +678,8 @@ vardef chem_set (suffix $) = fi endfor if not chem_front[$] : % adjust rotation - chem_rotation := (chem_rotation + angle(chem_pair1)-angle(chem_pair3)) mod 360 ; + chem_num4 := angle(chem_pair1)-angle(chem_pair3) ; + chem_rotation := (chem_rotation + chem_num4) mod 360 ; fi ; chem_t := identity chem_transformed($) ; chem_pair4 := (point chem_num3 of chem_b_path[$]) transformed chem_t ; @@ -674,6 +687,9 @@ vardef chem_set (suffix $) = currentpicture := currentpicture shifted chem_pair4 ; chem_origin := chem_origin shifted chem_pair4 ; fi + if not chem_front[$] : % adjust rotation + chem_rotation := chem_rotation zmod chem_num9 ; + fi fi chem_substituent := 0 ; fi ; @@ -1571,9 +1587,9 @@ vardef chem_rot (suffix $) (expr d, s) = % ROT chem_rotation := 0 else : chem_num0 := if chem_stacked[$] : 3 else : 0 fi ; - chem_num1 := .5(angle(point d+chem_num0 of chem_b_path[$]) - + chem_num1 := .5(angle(point d+chem_num0 of chem_b_path[$]) - angle(point d+chem_num0-1 of chem_b_path[$])) ; - chem_rotation := (chem_rotation + s*chem_num1) mod 360 ; + chem_rotation := (chem_rotation + s*chem_num1) zmod 360 ; fi fi enddef ; @@ -1584,7 +1600,7 @@ vardef chem_mir (suffix $) (expr d, s) = % MIR if not chem_front[$] : if d=0 : % inversion if chem_mirror=origin : - chem_rotation := (chem_rotation + 180*s) mod 360 ; + chem_rotation := (chem_rotation + 180*s) zmod 360 ; else : chem_mirror := chem_mirror rotated 90 ; fi @@ -1600,7 +1616,7 @@ vardef chem_mir (suffix $) (expr d, s) = % MIR chem_num0 := -360 - chem_num0 ; fi chem_num0 := chem_num0 * s ; - chem_rotation := (chem_rotation + 2chem_num0) mod 360 ; + chem_rotation := (chem_rotation + 2chem_num0) zmod 360 ; chem_mirror := origin ; fi fi |