tdf#80194 editeng: fix auto subscript calculations

...and auto superscript too (although not as noticably).

THIS WILL CHANGE THE POSITION OF EDITENG SUBSCRIPTS
AND SUPERSCRIPTS IN EXISTING DOCUMENTS!
That is because they were very poorly placed
before - using a formula that is very different
from how Writer does it. Everyone in the bug reports
indicates that Writer does it good, but Impress
does it really bad. (tdf#89849, tdf#63083)

FOR EXAMPLE, when the char-size is reduced to
the default OF 58%, it will now be raised by 33%, not 42%.
Likewise, the subscript will now be lowered by 8%, not 42%.

THIS AFFECTS/FIXES Writer textboxes, Calc, Draw/Impress.

"Automatic" indicates that there is not a
"correct" answer, but that the computer should make
it "look good", so the user should be able to accept
this change in positioning, as long as it looks good.

The number of documents affected might be less than
one would expect. By default .uno:SuperScript
does NOT set auto mode (although Format-Character does).
Since most people would use the toolbar instead of the
format menu to create a superscript, auto will be rare.
So there will be relatively few cases where
subscripts are automatic in editeng, especially since
it looks so poor that most people probably turned
automatic off...

This patch has no effect on non-automatic escapement.

It uses the same fomula that calculated DFLT_ESC_SUB
(since it isn't an arbitrarily chosen value).
This is an approximation of the formula that Writer
uses (since Writer does exact calculations based
on each font's metrics).
This Writer-inspired formula was introduced in LO 6.4
for more accurate exporting to MSO
word processing formats (tdf#127316).

Change-Id: I0267810efe31a2b3be41bf2d39e2278ce9bc99e9
Reviewed-on: https://gerrit.libreoffice.org/c/core/+/88911
Tested-by: Jenkins
Reviewed-by: Ilmari Lauhakangas <ilmari.lauhakangas@libreoffice.org>
Reviewed-by: Justin Luth <justin_luth@sil.org>

3 files changed, 6 insertions, 6 deletions

diff --git a/editeng/source/editeng/editattr.cxx b/editeng/source/editeng/editattr.cxx
index f000cf793560..a99e4d496f74 100644
--- a/editeng/source/editeng/editattr.cxx
+++ b/editeng/source/editeng/editattr.cxx
@@ -273,9 +273,9 @@ void EditCharAttribEscapement::SetFont( SvxFont& rFont, OutputDevice* )
 
     short nEsc = static_cast<const SvxEscapementItem*>(GetItem())->GetEsc();
     if ( nEsc == DFLT_ESC_AUTO_SUPER )
-        nEsc = 100 - nProp;
+        nEsc =  .8 * (100 - nProp);
     else if ( nEsc == DFLT_ESC_AUTO_SUB )
-        nEsc = sal::static_int_cast< short >( -( 100 - nProp ) );
+        nEsc =  .2 * -(100 - nProp);
     rFont.SetEscapement( nEsc );
 }
 
diff --git a/editeng/source/editeng/editdoc.cxx b/editeng/source/editeng/editdoc.cxx
index f3f55edf60c1..42fc1f3cc22c 100644
--- a/editeng/source/editeng/editdoc.cxx
+++ b/editeng/source/editeng/editdoc.cxx
@@ -2008,9 +2008,9 @@ void CreateFont( SvxFont& rFont, const SfxItemSet& rSet, bool bSearchInParent, S
 
         short nEsc = rEsc.GetEsc();
         if ( nEsc == DFLT_ESC_AUTO_SUPER )
-            nEsc = 100 - nProp;
+            nEsc = .8 * (100 - nProp);
         else if ( nEsc == DFLT_ESC_AUTO_SUB )
-            nEsc = sal::static_int_cast< short >( -( 100 - nProp ) );
+            nEsc = .2 * -(100 - nProp);
         rFont.SetEscapement( nEsc );
     }
     if ( bSearchInParent || ( rSet.GetItemState( EE_CHAR_PAIRKERNING ) == SfxItemState::SET ) )
diff --git a/editeng/source/editeng/impedit4.cxx b/editeng/source/editeng/impedit4.cxx
index 67e924653618..25d7ecc0aa8a 100644
--- a/editeng/source/editeng/impedit4.cxx
+++ b/editeng/source/editeng/impedit4.cxx
@@ -930,12 +930,12 @@ void ImpEditEngine::WriteItemAsRTF( const SfxPoolItem& rItem, SvStream& rOutput,
             short nEsc = static_cast<const SvxEscapementItem&>(rItem).GetEsc();
             if ( nEsc == DFLT_ESC_AUTO_SUPER )
             {
-                nEsc = 100 - nProp;
+                nEsc =  .8 * (100 - nProp);
                 nProp100++; // A 1 afterwards means 'automatic'.
             }
             else if ( nEsc == DFLT_ESC_AUTO_SUB )
             {
-                nEsc = sal::static_int_cast< short >( -( 100 - nProp ) );
+                nEsc =  .2 * -(100 - nProp);
                 nProp100++;
             }
             // SWG: