tdf#145700 Improve lighting in extruded custom shapes

The fix tries to make rendering similar to MS Office.

The ODF standard follows closely the extrusion in RTF and MS binary
format. Rendering uses the 3D scene engine.

The main problem was, that the z-component of the direction was
interpreted with opposite sign. As result the maximum of a light was at
false position. Especially a direction from the observer to the object
has produced a light behind the shape and so looks as if light was off.

The wrong z-direction has produced lighting, which was less intensive
than in MS Office. To compensate that, a third light source was added
as workaround. That part is removed.

Second problem was wrong use of 3D-scene D3DMaterialSpecularIntensity
and D3DMaterialSpecular (= UI Specular color). That was not only wrong
in OOo but in my previous patch too.
D3DMaterialSpecularIntensity corresponds to MS property 'c3DShininess'.
Relationship is Intensity = 2^c3DShininess.
D3DMaterialSpecular is calculated from MS property c3DSpecularAmt and
and c3DKeyIntensity. The light source was missing, but needs to be
included, because c3DSpecularAmt is 'the ratio of incident to specular
light that is reflected on a shape'.
The old unit tests are adapted to this change.

MS gives no information how it softens a light in case of harsh=false.
ODF specifies it as 'implementation-defined'. The patch uses four
additional lights, which have directions in 60° angle to the original
light. The light intensity is distributed. That comes near to rendering
in MS Office. Changing our 3D engine to provide 'soft' lights was not
doable for me.

The way MS Office renders a 'metal' surface is different from ODF
specification. To distinguish the kinds, I have introduced a new
property MetalType. I have discussed it with the ODF TC (see minutes
from 2022-02-07) and got the advise to use namespaced values.
Therefore the datatype is not boolean.

The 'Surface' drop-down in the extrusion bar is changed to make the two
kinds of rendering 'Metal' available to the user.

If a user sets surface 'Metal' in the UI of MS Office, it sets not only
fc3DMetallic but reduces the value of c3DDiffuseAmt in addition. Our
3D-scene engine has the corresponding ODF attribute dr3d:diffuse-color
not implemented. To get a similar rendering I change the material color
of the 3D-objects as workaround.

Change-Id: Ia986b9c318b4c79688e0c0e2d858215b9d612fdc
Reviewed-on: https://gerrit.libreoffice.org/c/core/+/128449
Tested-by: Jenkins
Reviewed-by: Regina Henschel <rb.henschel@t-online.de>

1 files changed, 89 insertions, 37 deletions

diff --git a/svx/source/toolbars/extrusionbar.cxx b/svx/source/toolbars/extrusionbar.cxx
index 659af238d77e..26ac4805cde0 100644
--- a/svx/source/toolbars/extrusionbar.cxx
+++ b/svx/source/toolbars/extrusionbar.cxx
@@ -18,6 +18,7 @@
  */
 
 
+#include <com/sun/star/drawing/EnhancedCustomShapeMetalType.hpp>
 #include <com/sun/star/drawing/EnhancedCustomShapeParameterPair.hpp>
 #include <com/sun/star/drawing/EnhancedCustomShapeParameterType.hpp>
 #include <com/sun/star/drawing/ShadeMode.hpp>
@@ -126,9 +127,9 @@ static void impl_execute( SfxRequest const & rReq, SdrCustomShapeGeometryItem& r
     {
         css::uno::Any* pAny = rGeometryItem.GetPropertyValueByName( sExtrusion, sExtrusion );
 
+        bool bOn(false);
         if( pAny )
         {
-            bool bOn(false);
             (*pAny) >>= bOn;
             bOn = !bOn;
             (*pAny) <<= bOn;
@@ -139,6 +140,23 @@ static void impl_execute( SfxRequest const & rReq, SdrCustomShapeGeometryItem& r
             aPropValue.Name = sExtrusion;
             aPropValue.Value <<= true;
             rGeometryItem.SetPropertyValue( sExtrusion,  aPropValue );
+            bOn = true;
+        }
+        // draw:extrusion-diffusion has default 0% and c3DDiffuseAmt has default 100%. We set property
+        // "Diffusion" with value 100% here if it does not exist already. This forces, that the
+        // property is written to file in case an extrusion is newly created, and users of old
+        // documents, which usually do not have this property, can force the value to 100% by toggling
+        // the extrusion off and on.
+        if (bOn)
+        {
+            pAny = rGeometryItem.GetPropertyValueByName(sExtrusion, u"Diffusion");
+            if (!pAny)
+            {
+                css::beans::PropertyValue aPropValue;
+                aPropValue.Name = u"Diffusion";
+                aPropValue.Value <<= 100.0;
+                rGeometryItem.SetPropertyValue( sExtrusion,  aPropValue );
+            }
         }
     }
     break;
@@ -335,52 +353,75 @@ static void impl_execute( SfxRequest const & rReq, SdrCustomShapeGeometryItem& r
                     break;
                 case 1: // matte
                 case 2: // plastic
-                case 3: // metal
+                case 3: // metal ODF
+                case 4: // metal MS Office
                     if (eOldShadeMode == ShadeMode_DRAFT)
                         eShadeMode = ShadeMode_FLAT; // ODF default
                     break;
             }
 
-            bool bMetal = nSurface == 3;
-
             // ODF has no dedicated property for 'surface'. MS Office binary format uses attribute
             // c3DSpecularAmt to distinguish between 'matte' (=0) and 'plastic'.
-            // From point of ODF, using not harsh light has similar effect.
+            // We do the same.
             double fOldSpecularity = 0.0;
             pAny = rGeometryItem.GetPropertyValueByName(sExtrusion, u"Specularity");
             if (pAny)
                 *pAny >>= fOldSpecularity;
             double fSpecularity = fOldSpecularity;
-            bool bOldIsFirstLightHarsh = true;
-            pAny = rGeometryItem.GetPropertyValueByName(sExtrusion, u"FirstLightHarsh");
-            if (pAny)
-                *pAny >>= bOldIsFirstLightHarsh;
-            bool bIsFirstLightHarsh = bOldIsFirstLightHarsh;
             switch( nSurface )
             {
             case 0: // wireframe
                 break;
             case 1: // matte
                 fSpecularity = 0.0;
-                bIsFirstLightHarsh = false;
                 break;
             case 2: // plastic
-            case 3: // metal
+            case 3: // metal ODF
+            case 4: // metal MS Office
                 if (basegfx::fTools::equalZero(fOldSpecularity, 0.0001))
-                    fSpecularity = 80; // estimated value, can be changed if necessary
-                if (!bOldIsFirstLightHarsh)
-                    bIsFirstLightHarsh = true;
+                    // MS Office uses 80000/65536. That is currently not allowed in ODF.
+                    // But the ODF error will be catched in xmloff.
+                    fSpecularity = 80000.0 / 655.36; // interpreted as %
                 break;
             }
 
+            // MS Office binary format uses attribute c3DDiffuseAmt with value =43712 (Fixed 16.16) in
+            // addition to the 'metal' flag. For other surface kinds default = 65536 is used.
+            // We toggle between 100 and 43712.0 / 655.36 here, to get better ODF -> MSO binary.
+            // We keep other values, those might be set outside regular UI, e.g by macro.
+            double fOldDiffusion = 100.0;
+            pAny = rGeometryItem.GetPropertyValueByName(sExtrusion, u"Diffusion");
+            if (pAny)
+                *pAny >>= fOldDiffusion;
+            double fDiffusion = fOldDiffusion;
+            if (nSurface == 4)
+            {
+                if (fOldDiffusion == 100.0)
+                    fDiffusion = 43712.0 / 655.36; // interpreted as %
+            }
+            else
+            {
+                if (basegfx::fTools::equalZero(fOldDiffusion - 43712.0 / 655.36, 0.0001))
+                    fDiffusion = 100.0;
+            }
+
             css::beans::PropertyValue aPropValue;
             aPropValue.Name = "ShadeMode";
             aPropValue.Value <<= eShadeMode;
             rGeometryItem.SetPropertyValue( sExtrusion, aPropValue );
 
             aPropValue.Name = "Metal";
-            aPropValue.Value <<= bMetal;
-            rGeometryItem.SetPropertyValue( sExtrusion,  aPropValue );
+            aPropValue.Value <<= nSurface == 3 || nSurface == 4;
+            rGeometryItem.SetPropertyValue(sExtrusion, aPropValue);
+
+            if (nSurface == 3 || nSurface == 4)
+            {
+                aPropValue.Name = "MetalType";
+                aPropValue.Value <<= nSurface == 4
+                                         ? EnhancedCustomShapeMetalType::MetalMSCompatible
+                                         : EnhancedCustomShapeMetalType::MetalODF;
+                rGeometryItem.SetPropertyValue(sExtrusion, aPropValue);
+            }
 
             if (!basegfx::fTools::equalZero(fOldSpecularity - fSpecularity, 0.0001))
             {
@@ -389,10 +430,10 @@ static void impl_execute( SfxRequest const & rReq, SdrCustomShapeGeometryItem& r
                 rGeometryItem.SetPropertyValue(sExtrusion, aPropValue);
             }
 
-            if (bOldIsFirstLightHarsh != bIsFirstLightHarsh)
+            if (!basegfx::fTools::equalZero(fOldDiffusion - fDiffusion, 0.0001))
             {
-                aPropValue.Name = "FirstLightHarsh";
-                aPropValue.Value <<= bIsFirstLightHarsh;
+                aPropValue.Name = "Diffusion";
+                aPropValue.Value <<= fDiffusion;
                 rGeometryItem.SetPropertyValue(sExtrusion, aPropValue);
             }
         }
@@ -404,16 +445,17 @@ static void impl_execute( SfxRequest const & rReq, SdrCustomShapeGeometryItem& r
         {
             sal_Int32 nLevel = rReq.GetArgs()->GetItem<SfxInt32Item>(SID_EXTRUSION_LIGHTING_INTENSITY)->GetValue();
 
-            double fBrightness;
-            double fLevel1;
-            double fLevel2;
+            double fBrightness; // c3DAmbientIntensity in MS Office
+            double fLevel1; // c3DKeyIntensity in MS Office
+            double fLevel2; // c3DFillIntensity in MS Office
 
+            // ToDo: "bright" values are different from MS Office. Should they be kept?
             switch( nLevel )
             {
             case 0: // bright
-                fBrightness = 34.0;
-                fLevel1 = 66.0;
-                fLevel2 = 66.0;
+                fBrightness = 33.0; // ODF default.
+                fLevel1 = 66.0; // ODF default
+                fLevel2 = 66.0; // ODF default
                 break;
             case 1: // normal
                 fBrightness = 15.0;
@@ -432,10 +474,6 @@ static void impl_execute( SfxRequest const & rReq, SdrCustomShapeGeometryItem& r
             aPropValue.Value <<= fBrightness;
             rGeometryItem.SetPropertyValue( sExtrusion,  aPropValue );
 
-            aPropValue.Name = "SecondLightHarsh";
-            aPropValue.Value <<= false;
-            rGeometryItem.SetPropertyValue( sExtrusion,  aPropValue );
-
             aPropValue.Name = "FirstLightLevel";
             aPropValue.Value <<= fLevel1;
             rGeometryItem.SetPropertyValue( sExtrusion,  aPropValue );
@@ -443,6 +481,12 @@ static void impl_execute( SfxRequest const & rReq, SdrCustomShapeGeometryItem& r
             aPropValue.Name = "SecondLightLevel";
             aPropValue.Value <<= fLevel2;
             rGeometryItem.SetPropertyValue( sExtrusion,  aPropValue );
+
+            // If a user sets light preset 'Dim' in MS Office, MS Office sets second light to harsh.
+            // In other cases it is soft.
+            aPropValue.Name = "SecondLightHarsh";
+            aPropValue.Value <<= nLevel == 2;
+            rGeometryItem.SetPropertyValue(sExtrusion, aPropValue);
         }
     }
     break;
@@ -665,8 +709,8 @@ static void getExtrusionDirectionState( SdrView const * pSdrView, SfxItemSet& rS
             }
 
             bool        bParallel = true;
-            Position3D  aViewPoint( 3472, -3472, 25000 );
-            double      fSkewAngle = -135;
+            Position3D  aViewPoint( 3472, -3472, 25000 ); // MSO default
+            double      fSkewAngle = -135; // MSO default
 
             pAny = rGeometryItem.GetPropertyValueByName( sExtrusion, "ProjectionMode" );
             sal_Int16 nProjectionMode = sal_Int16();
@@ -869,25 +913,33 @@ static void getExtrusionSurfaceState( SdrView const * pSdrView, SfxItemSet& rSet
             sal_Int32 nSurface = 0; // wire frame
 
             ShadeMode eShadeMode( ShadeMode_FLAT );
-            pAny = rGeometryItem.GetPropertyValueByName( sExtrusion, "ShadeMode" );
+            pAny = rGeometryItem.GetPropertyValueByName( sExtrusion, u"ShadeMode" );
             if( pAny )
                 *pAny >>= eShadeMode;
 
             if (eShadeMode != ShadeMode_DRAFT)
             {
                 bool bMetal = false;
-                pAny = rGeometryItem.GetPropertyValueByName( sExtrusion, "Metal" );
+                pAny = rGeometryItem.GetPropertyValueByName( sExtrusion, u"Metal" );
                 if( pAny )
                     *pAny >>= bMetal;
 
                 if( bMetal )
                 {
-                    nSurface = 3; // metal
+                    nSurface = 3; // metal ODF
+                    sal_Int16 eMetalType;
+                    pAny = rGeometryItem.GetPropertyValueByName( sExtrusion, u"MetalType" );
+                    if (pAny)
+                    {
+                        *pAny >>= eMetalType;
+                        if (eMetalType == EnhancedCustomShapeMetalType::MetalMSCompatible)
+                            nSurface = 4; // metal MS Office
+                    }
                 }
                 else
                 {
                     double fSpecularity = 0;
-                    pAny = rGeometryItem.GetPropertyValueByName( sExtrusion, "Specularity" );
+                    pAny = rGeometryItem.GetPropertyValueByName( sExtrusion, u"Specularity" );
                     if( pAny )
                         *pAny >>= fSpecularity;
 
@@ -951,7 +1003,7 @@ static void getExtrusionDepthState( SdrView const * pSdrView, SfxItemSet& rSet )
                     continue;
             }
 
-            double fDepth = 1270.0;
+            double fDepth = 1270.0; // =36pt ODF default
             pAny = rGeometryItem.GetPropertyValueByName( sExtrusion, "Depth" );
             if( pAny )
             {