tdf#80194 autoEsc: use fontmetrics in calculation

This replaces the previous 7.0 patch in
commit 2940d1905b921d9909b08b1e32014d3c44474ef0
where the following is still true:
    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).

Instead of using the previous patch's 80%/20%
generalization, copy Writer's use of the actual
ascent and descent of the font to determine
the best position for the subscript or superscript.

Change-Id: I0f10f6174b0709f3bc3b9acdc54b7b1fd59c5ee2
Reviewed-on: https://gerrit.libreoffice.org/c/core/+/90489
Reviewed-by: Justin Luth <justin_luth@sil.org>
Reviewed-by: Miklos Vajna <vmiklos@collabora.com>
Tested-by: Justin Luth <justin_luth@sil.org>
diff --git a/editeng/source/editeng/editattr.cxx b/editeng/source/editeng/editattr.cxx
index a99e4d4..e48445c 100644
--- a/editeng/source/editeng/editattr.cxx
+++ b/editeng/source/editeng/editattr.cxx
@@ -266,17 +266,13 @@ EditCharAttribEscapement::EditCharAttribEscapement( const SvxEscapementItem& rAt
    assert(rAttr.Which() == EE_CHAR_ESCAPEMENT);
}

void EditCharAttribEscapement::SetFont( SvxFont& rFont, OutputDevice* )
void EditCharAttribEscapement::SetFont( SvxFont& rFont, OutputDevice* pOutDev )
{
    sal_uInt16 const nProp = static_cast<const SvxEscapementItem*>(GetItem())->GetProportionalHeight();
    rFont.SetPropr( static_cast<sal_uInt8>(nProp) );

    short nEsc = static_cast<const SvxEscapementItem*>(GetItem())->GetEsc();
    if ( nEsc == DFLT_ESC_AUTO_SUPER )
        nEsc =  .8 * (100 - nProp);
    else if ( nEsc == DFLT_ESC_AUTO_SUB )
        nEsc =  .2 * -(100 - nProp);
    rFont.SetEscapement( nEsc );
    rFont.SetNonAutoEscapement( nEsc, pOutDev );
}


diff --git a/editeng/source/editeng/editdoc.cxx b/editeng/source/editeng/editdoc.cxx
index 42fc1f3..9e9eb17 100644
--- a/editeng/source/editeng/editdoc.cxx
+++ b/editeng/source/editeng/editdoc.cxx
@@ -2007,11 +2007,7 @@ void CreateFont( SvxFont& rFont, const SfxItemSet& rSet, bool bSearchInParent, S
        rFont.SetPropr( static_cast<sal_uInt8>(nProp) );

        short nEsc = rEsc.GetEsc();
        if ( nEsc == DFLT_ESC_AUTO_SUPER )
            nEsc = .8 * (100 - nProp);
        else if ( nEsc == DFLT_ESC_AUTO_SUB )
            nEsc = .2 * -(100 - nProp);
        rFont.SetEscapement( nEsc );
        rFont.SetNonAutoEscapement( nEsc );
    }
    if ( bSearchInParent || ( rSet.GetItemState( EE_CHAR_PAIRKERNING ) == SfxItemState::SET ) )
        rFont.SetKerning( rSet.Get( EE_CHAR_PAIRKERNING ).GetValue() ? FontKerning::FontSpecific : FontKerning::NONE );
diff --git a/editeng/source/editeng/impedit4.cxx b/editeng/source/editeng/impedit4.cxx
index 25d7ecc..050eed8 100644
--- a/editeng/source/editeng/impedit4.cxx
+++ b/editeng/source/editeng/impedit4.cxx
@@ -69,6 +69,7 @@
#include <unotools/textsearch.hxx>
#include <comphelper/processfactory.hxx>
#include <vcl/help.hxx>
#include <vcl/metric.hxx>
#include <svtools/rtfkeywd.hxx>
#include <editeng/edtdlg.hxx>

@@ -928,14 +929,23 @@ void ImpEditEngine::WriteItemAsRTF( const SfxPoolItem& rItem, SvStream& rOutput,
            sal_uInt16 const nProp = static_cast<const SvxEscapementItem&>(rItem).GetProportionalHeight();
            sal_uInt16 nProp100 = nProp*100;    // For SWG-Token Prop in 100th percent.
            short nEsc = static_cast<const SvxEscapementItem&>(rItem).GetEsc();
            const FontMetric& rFontMetric = GetRefDevice()->GetFontMetric();
            double fFontHeight = rFontMetric.GetAscent() + rFontMetric.GetDescent();
            double fAutoAscent = .8;
            double fAutoDescent = .2;
            if ( fFontHeight )
            {
                fAutoAscent = rFontMetric.GetAscent() / fFontHeight;
                fAutoDescent = rFontMetric.GetDescent() / fFontHeight;
            }
            if ( nEsc == DFLT_ESC_AUTO_SUPER )
            {
                nEsc =  .8 * (100 - nProp);
                nEsc =  fAutoAscent * (100 - nProp);
                nProp100++; // A 1 afterwards means 'automatic'.
            }
            else if ( nEsc == DFLT_ESC_AUTO_SUB )
            {
                nEsc =  .2 * -(100 - nProp);
                nEsc =  fAutoDescent * -(100 - nProp);
                nProp100++;
            }
            // SWG:
diff --git a/editeng/source/items/svxfont.cxx b/editeng/source/items/svxfont.cxx
index a8792df..f6ff6cf 100644
--- a/editeng/source/items/svxfont.cxx
+++ b/editeng/source/items/svxfont.cxx
@@ -17,6 +17,7 @@
 *   the License at http://www.apache.org/licenses/LICENSE-2.0 .
 */

#include <vcl/metric.hxx>
#include <vcl/outdev.hxx>
#include <vcl/print.hxx>
#include <tools/debug.hxx>
@@ -55,6 +56,36 @@ SvxFont::SvxFont( const SvxFont &rFont )
    SetLanguage(rFont.GetLanguage());
}

void SvxFont::SetNonAutoEscapement(short nNewEsc, const OutputDevice* pOutDev)
{
    nEsc = nNewEsc;
    if ( abs(nEsc) == DFLT_ESC_AUTO_SUPER )
    {
        double fAutoAscent = .8;
        double fAutoDescent = .2;
        if ( pOutDev )
        {
            const FontMetric& rFontMetric = pOutDev->GetFontMetric();
            double fFontHeight = rFontMetric.GetAscent() + rFontMetric.GetDescent();
            if ( fFontHeight )
            {
                fAutoAscent = rFontMetric.GetAscent() / fFontHeight;
                fAutoDescent = rFontMetric.GetDescent() / fFontHeight;
            }
        }

        if ( nEsc == DFLT_ESC_AUTO_SUPER )
            nEsc = fAutoAscent * (100 - nPropr);
        else //DFLT_ESC_AUTO_SUB
            nEsc = fAutoDescent * -(100 - nPropr);
    }

    if ( nEsc > MAX_ESC_POS )
        nEsc = MAX_ESC_POS;
    else if  ( nEsc < -MAX_ESC_POS )
        nEsc = -MAX_ESC_POS;
}

void SvxFont::DrawArrow( OutputDevice &rOut, const tools::Rectangle& rRect,
    const Size& rSize, const Color& rCol, bool bLeft )
{
diff --git a/include/editeng/svxfont.hxx b/include/editeng/svxfont.hxx
index b584bb8..1a33e73 100644
--- a/include/editeng/svxfont.hxx
+++ b/include/editeng/svxfont.hxx
@@ -49,6 +49,8 @@ public:
    // Methods for Superscript/Subscript
    short GetEscapement() const { return nEsc; }
    void SetEscapement( const short nNewEsc ) { nEsc = nNewEsc; }
    // set specific values instead of automatic, and ensure valid value. Depends on nPropr being set already.
    void SetNonAutoEscapement(short nNewEsc, const OutputDevice* pOutDev = nullptr);

    sal_uInt8 GetPropr() const { return nPropr; }
    void SetPropr( const sal_uInt8 nNewPropr ) { nPropr = nNewPropr; }