Generalize DegreeN

This potentially allows to introduce other degree fractions easily,
like Degree<sal_Int64, 60000>, with automatically defined conversion
functions.

Change-Id: Id1c32d9e029943844bdc833178c1f99387ff87fc
Reviewed-on: https://gerrit.libreoffice.org/c/core/+/125640
Tested-by: Jenkins
Reviewed-by: Mike Kaganski <mike.kaganski@collabora.com>

12 files changed, 36 insertions, 23 deletions

diff --git a/filter/source/msfilter/msdffimp.cxx b/filter/source/msfilter/msdffimp.cxx
index 74b7bece8644..8e35938ceb5c 100644
--- a/filter/source/msfilter/msdffimp.cxx
+++ b/filter/source/msfilter/msdffimp.cxx
@@ -1293,7 +1293,7 @@ static void ApplyRectangularGradientAsBitmap( const SvxMSDffManager& rManager, S
         if ( bRotateWithShape )
         {
             // convert from 100th to 10th degrees
-            aBitmapEx.Rotate( toDegree10(nFix16Angle), rShadeColors[ 0 ].aColor );
+            aBitmapEx.Rotate( to<Degree10>(nFix16Angle), rShadeColors[ 0 ].aColor );
 
             BmpMirrorFlags nMirrorFlags = BmpMirrorFlags::NONE;
             if ( rObjData.nSpFlags & ShapeFlag::FlipV )
diff --git a/include/tools/degree.hxx b/include/tools/degree.hxx
index 74a27a2c2d35..1f2b2e2f8853 100644
--- a/include/tools/degree.hxx
+++ b/include/tools/degree.hxx
@@ -13,17 +13,28 @@
 #include <basegfx/numeric/ftools.hxx>
 #include <sal/types.h>
 #include <o3tl/strong_int.hxx>
+#include <o3tl/unit_conversion.hxx>
 #include <cstdlib>
 #include <math.h>
+#include <numeric>
+#include <utility>
+
+template <int N> struct FractionTag;
+// 1/Nth fraction of a degree
+template <typename I, int N> using Degree = o3tl::strong_int<I, FractionTag<N>>;
+
+template <typename I, int N> char (&NofDegree(Degree<I, N>))[N]; // helper
+// Nof<DegreeN> gives compile-time constant N, needed in templates
+template <class D> constexpr int Nof = sizeof(NofDegree(std::declval<D>()));
 
 /** tenths of a Degree, normally rotation */
-typedef o3tl::strong_int<sal_Int16, struct Degree10Tag> Degree10;
+typedef Degree<sal_Int16, 10> Degree10;
 
 /** custom literal */
 constexpr Degree10 operator""_deg10(unsigned long long n) { return Degree10{ n }; }
 
 /** hundredths of a Degree, normally rotation */
-typedef o3tl::strong_int<sal_Int32, struct Degree100Tag> Degree100;
+typedef Degree<sal_Int32, 100> Degree100;
 
 // Android has trouble calling the correct overload of std::abs
 #ifdef ANDROID
@@ -37,12 +48,14 @@ constexpr Degree100 operator""_deg100(unsigned long long n) { return Degree100{
 
 /** conversion functions */
 
-inline Degree100 toDegree100(Degree10 x) { return Degree100(x.get() * 10); }
-inline double toRadians(Degree10 x) { return basegfx::deg2rad<10>(x.get()); }
-inline double toDegrees(Degree10 x) { return x.get() / 10.0; }
+template <class To, typename IofFrom, int NofFrom> inline To to(Degree<IofFrom, NofFrom> x)
+{
+    constexpr sal_Int64 m = Nof<To> / std::gcd(Nof<To>, NofFrom);
+    constexpr sal_Int64 d = NofFrom / std::gcd(Nof<To>, NofFrom);
+    return To{ o3tl::convert(x.get(), m, d) };
+}
 
-inline Degree10 toDegree10(Degree100 x) { return Degree10((x.get() + 5) / 10); }
-inline double toRadians(Degree100 x) { return basegfx::deg2rad<100>(x.get()); }
-inline double toDegrees(Degree100 x) { return x.get() / 100.0; }
+template <class D> inline double toRadians(D x) { return basegfx::deg2rad<Nof<D>>(x.get()); }
+template <class D> inline double toDegrees(D x) { return x.get() / static_cast<double>(Nof<D>); }
 
 /* vim:set shiftwidth=4 softtabstop=4 expandtab cinoptions=b1,g0,N-s cinkeys+=0=break: */
diff --git a/sc/source/ui/view/output2.cxx b/sc/source/ui/view/output2.cxx
index 31b0076bc0bc..7c8758bb75e1 100644
--- a/sc/source/ui/view/output2.cxx
+++ b/sc/source/ui/view/output2.cxx
@@ -5078,7 +5078,7 @@ void ScOutputData::DrawRotated(bool bPixelToLogic)
                                 if ( nAttrRotate )
                                 {
                                     // attribute is 1/100, Font 1/10 degrees
-                                    nOriVal = toDegree10(nAttrRotate);
+                                    nOriVal = to<Degree10>(nAttrRotate);
 
                                     double nAddX = 0.0;
                                     double nAddY = 0.0;
diff --git a/svx/source/dialog/dialcontrol.cxx b/svx/source/dialog/dialcontrol.cxx
index fe88a426649d..e6c7c8e43b3b 100644
--- a/svx/source/dialog/dialcontrol.cxx
+++ b/svx/source/dialog/dialcontrol.cxx
@@ -77,7 +77,7 @@ void DialControlBmp::DrawElements( const OUString& rText, Degree100 nAngle )
         // rotated text
         vcl::Font aFont( GetFont() );
         aFont.SetColor( GetTextColor() );
-        aFont.SetOrientation( toDegree10(nAngle) );  // Font uses 1/10 degrees
+        aFont.SetOrientation( to<Degree10>(nAngle) );  // Font uses 1/10 degrees
         aFont.SetWeight( WEIGHT_BOLD );
         SetFont( aFont );
 
diff --git a/svx/source/svdraw/svdfmtf.cxx b/svx/source/svdraw/svdfmtf.cxx
index 93c5da9278e1..94d54040cd03 100644
--- a/svx/source/svdraw/svdfmtf.cxx
+++ b/svx/source/svdraw/svdfmtf.cxx
@@ -1051,7 +1051,7 @@ void ImpSdrGDIMetaFileImport::ImportText( const Point& rPos, const OUString& rSt
         aAttr.Put(XFillColorItem(OUString(), aFnt.GetFillColor()));
         pText->SetMergedItemSet(aAttr);
     }
-    Degree100 nAngle = toDegree100(aFnt.GetOrientation());
+    Degree100 nAngle = to<Degree100>(aFnt.GetOrientation());
     if ( nAngle )
         pText->SdrAttrObj::NbcRotate(aPos,nAngle);
     InsertObj( pText, false );
diff --git a/svx/source/svdraw/svdoashp.cxx b/svx/source/svdraw/svdoashp.cxx
index 3b1612b15f68..52625388a32e 100644
--- a/svx/source/svdraw/svdoashp.cxx
+++ b/svx/source/svdraw/svdoashp.cxx
@@ -1768,7 +1768,7 @@ void SdrObjCustomShape::ImpCheckCustomGluePointsAreAdded()
                 ShearPoint(aPoly[i],maRect.Center(), fTan );
         }
         if (maGeo.nRotationAngle)
-            aPoly.Rotate( maRect.Center(), toDegree10(maGeo.nRotationAngle) );
+            aPoly.Rotate( maRect.Center(), to<Degree10>(maGeo.nRotationAngle) );
 
         tools::Rectangle aBoundRect( aPoly.GetBoundRect() );
         sal_Int32 nXDiff = aBoundRect.Left() - maRect.Left();
diff --git a/svx/source/svdraw/svdograf.cxx b/svx/source/svdraw/svdograf.cxx
index 027301bedb43..67bd14cc8622 100644
--- a/svx/source/svdraw/svdograf.cxx
+++ b/svx/source/svdraw/svdograf.cxx
@@ -435,7 +435,7 @@ GraphicAttr SdrGrafObj::GetGraphicAttr( SdrGrafObjTransformsAttrs nTransformFlag
         }
 
         if( bRotate )
-            aActAttr.SetRotation( toDegree10(maGeo.nRotationAngle ) );
+            aActAttr.SetRotation( to<Degree10>(maGeo.nRotationAngle ) );
     }
 
     return aActAttr;
diff --git a/svx/source/svdraw/svdpdf.cxx b/svx/source/svdraw/svdpdf.cxx
index 789e5d360477..4fcfb21fca7a 100644
--- a/svx/source/svdraw/svdpdf.cxx
+++ b/svx/source/svdraw/svdpdf.cxx
@@ -834,7 +834,7 @@ void ImpSdrPdfImport::InsertTextObject(const Point& rPos, const Size& rSize, con
         aAttr.Put(XFillColorItem(OUString(), aFont.GetFillColor()));
         pText->SetMergedItemSet(aAttr);
     }
-    Degree100 nAngle = toDegree100(aFont.GetOrientation());
+    Degree100 nAngle = to<Degree100>(aFont.GetOrientation());
     if (nAngle)
         pText->SdrAttrObj::NbcRotate(aPosition, nAngle);
     InsertObj(pText, false);
diff --git a/sw/source/core/draw/dflyobj.cxx b/sw/source/core/draw/dflyobj.cxx
index d5497f9f2098..5298f1a296ba 100644
--- a/sw/source/core/draw/dflyobj.cxx
+++ b/sw/source/core/draw/dflyobj.cxx
@@ -386,7 +386,7 @@ void SwVirtFlyDrawObj::Rotate(const Point& rRef, Degree100 nAngle100, double sn,
     {
         // RotGrfFlyFrame: Here is where the positively completed rotate interaction is executed.
         // Rotation is in 1/100th degree and may be signed (!)
-        Degree10 nAngle10 = toDegree10(nAngle100);
+        Degree10 nAngle10 = to<Degree10>(nAngle100);
 
         while(nAngle10 < 0_deg10)
         {
@@ -1174,7 +1174,7 @@ Degree100 SwVirtFlyDrawObj::GetRotateAngle() const
     if(ContainsSwGrfNode())
     {
         Size aSize;
-        return toDegree100(getPossibleRotationFromFraphicFrame(aSize));
+        return to<Degree100>(getPossibleRotationFromFraphicFrame(aSize));
     }
     else
     {
diff --git a/sw/source/filter/ww8/docxattributeoutput.cxx b/sw/source/filter/ww8/docxattributeoutput.cxx
index 40656f6e3bf7..bcdd1af1af4f 100644
--- a/sw/source/filter/ww8/docxattributeoutput.cxx
+++ b/sw/source/filter/ww8/docxattributeoutput.cxx
@@ -5143,7 +5143,7 @@ void DocxAttributeOutput::FlyFrameGraphic( const SwGrfNode* pGrfNode, const Size
         if (Degree10 nRot = rSet.Get(RES_GRFATR_ROTATION).GetValue())
         {
             // RES_GRFATR_ROTATION is in 10ths of degree; convert to 100ths for macro
-            sal_uInt32 mOOXMLRot = oox::drawingml::ExportRotateClockwisify(toDegree100(nRot));
+            sal_uInt32 mOOXMLRot = oox::drawingml::ExportRotateClockwisify(to<Degree100>(nRot));
             xFrameAttributes->add(XML_rot, OString::number(mOOXMLRot));
         }
     }
diff --git a/sw/source/uibase/shells/frmsh.cxx b/sw/source/uibase/shells/frmsh.cxx
index 05187b5964dc..4463908f4b22 100644
--- a/sw/source/uibase/shells/frmsh.cxx
+++ b/sw/source/uibase/shells/frmsh.cxx
@@ -400,7 +400,7 @@ void SwFrameShell::Execute(SfxRequest &rReq)
 
                 if (pArgs && SfxItemState::SET == pArgs->GetItemState(SID_ATTR_TRANSFORM_DELTA_ANGLE, false, &pItem))
                 {
-                    const Degree10 nDeltaRot = toDegree10(static_cast<const SdrAngleItem*>(pItem)->GetValue());
+                    const Degree10 nDeltaRot = to<Degree10>(static_cast<const SdrAngleItem*>(pItem)->GetValue());
                     aMgr.SetRotation(nOldRot, nOldRot + nDeltaRot, rRotation.GetUnrotatedSize());
                 }
 
@@ -410,7 +410,7 @@ void SwFrameShell::Execute(SfxRequest &rReq)
                 // 100th degrees in SID_ATTR_TRANSFORM_ANGLE to 10th degrees in RES_GRFATR_ROTATION
                 if (pArgs && SfxItemState::SET == pArgs->GetItemState(SID_ATTR_TRANSFORM_ANGLE, false, &pItem))
                 {
-                    const Degree10 nNewRot = toDegree10(static_cast<const SdrAngleItem*>(pItem)->GetValue());
+                    const Degree10 nNewRot = to<Degree10>(static_cast<const SdrAngleItem*>(pItem)->GetValue());
 
                     // RotGrfFlyFrame: Rotation change here, SwFlyFrameAttrMgr aMgr is available
                     aMgr.SetRotation(nOldRot, nNewRot, rRotation.GetUnrotatedSize());
diff --git a/sw/source/uibase/shells/grfsh.cxx b/sw/source/uibase/shells/grfsh.cxx
index 1aa4b210a8a2..fa293272d0b9 100644
--- a/sw/source/uibase/shells/grfsh.cxx
+++ b/sw/source/uibase/shells/grfsh.cxx
@@ -392,7 +392,7 @@ void SwGrfShell::Execute(SfxRequest &rReq)
                 const SwRotationGrf& rRotation = aTmpSet.Get(RES_GRFATR_ROTATION);
                 nCurrentRotation = rRotation.GetValue();
                 aUnrotatedSize = rRotation.GetUnrotatedSize();
-                aSet.Put(SdrAngleItem(SID_ATTR_TRANSFORM_ANGLE, toDegree100(nCurrentRotation)));
+                aSet.Put(SdrAngleItem(SID_ATTR_TRANSFORM_ANGLE, to<Degree100>(nCurrentRotation)));
             }
 
             SwAbstractDialogFactory* pFact = SwAbstractDialogFactory::Create();
@@ -507,7 +507,7 @@ void SwGrfShell::Execute(SfxRequest &rReq)
                 // RotGrfFlyFrame: Get and process evtl. changed RotationAngle
                 if ( SfxItemState::SET == pSet->GetItemState(SID_ATTR_TRANSFORM_ANGLE, false, &pItem ))
                 {
-                    const Degree10 aNewRotation = toDegree10(static_cast<const SdrAngleItem*>(pItem)->GetValue() % 36000_deg100);
+                    const Degree10 aNewRotation = to<Degree10>(static_cast<const SdrAngleItem*>(pItem)->GetValue() % 36000_deg100);
 
                     // RotGrfFlyFrame: Possible rotation change here, SwFlyFrameAttrMgr aMgr is available
                     aMgr.SetRotation(nCurrentRotation, aNewRotation, aUnrotatedSize);
@@ -984,7 +984,7 @@ void SwGrfShell::GetAttrStateForRotation(SfxItemSet &rSet)
                 SfxItemSetFixed<RES_GRFATR_ROTATION, RES_GRFATR_ROTATION> aSet( rShell.GetAttrPool() );
                 rShell.GetCurAttr( aSet );
                 const SwRotationGrf& rRotation = aSet.Get(RES_GRFATR_ROTATION);
-                rSet.Put(SdrAngleItem(SID_ATTR_TRANSFORM_ANGLE, toDegree100(rRotation.GetValue())));
+                rSet.Put(SdrAngleItem(SID_ATTR_TRANSFORM_ANGLE, to<Degree100>(rRotation.GetValue())));
                 break;
             }
             default: