Justin Luth
6dd6891a3d
and stop an automatic 180 reversal on import. Some documents had gradient reversals on every round trip, typically when the angle was 0-179 (mainly seen in ODT examples, since DOCX/RTF imports defaulted to be angle 180). The negative sign has special meaning, indicating that the start and end colors should be swapped. Well, swapping colors was not intentional in the export logic. Previously there was a mistaken idea that any angles > 180 needed to be swapped on import, and likely that is what prompted this overly complicated formula to try to avoid any angle > 180 during export by allowing negative angles. This tdf#126533 patchset has already eliminated import checks for angles > 180, so now a sane formula can be applied on export. In order to do that, we have to avoid emulating color swaps with 180 degree rotations at import time. So ONLY do color swapping with start/end, and leave the angle alone. That GREATLY helps unit tests (which otherwise would flip-flop the angle and the color start/stop). Very unhelpful was an undocumented, indecipherable inversion when converting to DML angle. Boy, I hope I got this right... make CppunitTest_sw_rtfexport8 \ CPPUNIT_TEST_NAME=testTdf159824_gradientAngle3 make CppunitTest_sw_rtfexport8 \ CPPUNIT_TEST_NAME=testTdf159824_gradientAngle4 make CppunitTest_sw_ooxmlexport7 \ CPPUNIT_TEST_NAME=testTdf126533_axialAngle2 Eliminating the inversion for ooxml7 test is fine since inversion does nothing to an axial. Otherwise, eliminating inversions corresponds to a color swap. Change-Id: I2aae0a7595807569ffc740689ff3840692d6159d Reviewed-on: https://gerrit.libreoffice.org/c/core/+/163798 Tested-by: Jenkins Reviewed-by: Justin Luth <jluth@mail.com>
Office Open XML (ooxml) Support
Support for Office Open XML, the office XML-format designed by Microsoft.
DrawingML Custom shapes and presets
Custom shapes are part of DrawingML and are different to binary ppt
and VML in older formats.
The import happens in oox/source/drawingml, where they are
imported as LO's enhanced custom shape's. see
offapi/com/sun/star/drawing/CustomShape.idl and
offapi/com/sun/star/drawing/EnhancedCustomShape*.idl
Check CustomShapeProperties::pushToPropSet() and see
how custom shape properties are converted.
Preset shapes are custom shapes whose guides and handles have been defined in OOXML specification. By specifying preset type and the adjustment values, the reset can be taken from the shape definition.
example of drawingml preset:
<a:prstGeom prst="star5">
<a:avLst/>
</a:prstGeom>
example of drawingml custom shape (equal to star5 preset):
<avLst xmlns="http://schemas.openxmlformats.org/drawingml/2006/main">
<gd name="adj" fmla="val 19098" />
<gd name="hf" fmla="val 105146" />
<gd name="vf" fmla="val 110557" />
</avLst>
<gdLst xmlns="http://schemas.openxmlformats.org/drawingml/2006/main">
<gd name="a" fmla="pin 0 adj 50000" />
<gd name="swd2" fmla="*/ wd2 hf 100000" />
<gd name="shd2" fmla="*/ hd2 vf 100000" />
<gd name="svc" fmla="*/ vc vf 100000" />
<gd name="dx1" fmla="cos swd2 1080000" />
<gd name="dx2" fmla="cos swd2 18360000" />
<gd name="dy1" fmla="sin shd2 1080000" />
<gd name="dy2" fmla="sin shd2 18360000" />
<gd name="x1" fmla="+- hc 0 dx1" />
<gd name="x2" fmla="+- hc 0 dx2" />
<gd name="x3" fmla="+- hc dx2 0" />
<gd name="x4" fmla="+- hc dx1 0" />
<gd name="y1" fmla="+- svc 0 dy1" />
<gd name="y2" fmla="+- svc 0 dy2" />
<gd name="iwd2" fmla="*/ swd2 a 50000" />
<gd name="ihd2" fmla="*/ shd2 a 50000" />
<gd name="sdx1" fmla="cos iwd2 20520000" />
<gd name="sdx2" fmla="cos iwd2 3240000" />
<gd name="sdy1" fmla="sin ihd2 3240000" />
<gd name="sdy2" fmla="sin ihd2 20520000" />
<gd name="sx1" fmla="+- hc 0 sdx1" />
<gd name="sx2" fmla="+- hc 0 sdx2" />
<gd name="sx3" fmla="+- hc sdx2 0" />
<gd name="sx4" fmla="+- hc sdx1 0" />
<gd name="sy1" fmla="+- svc 0 sdy1" />
<gd name="sy2" fmla="+- svc 0 sdy2" />
<gd name="sy3" fmla="+- svc ihd2 0" />
<gd name="yAdj" fmla="+- svc 0 ihd2" />
</gdLst>
<ahLst xmlns="http://schemas.openxmlformats.org/drawingml/2006/main">
<ahXY gdRefY="adj" minY="0" maxY="50000">
<pos x="hc" y="yAdj" />
</ahXY>
</ahLst>
<cxnLst xmlns="http://schemas.openxmlformats.org/drawingml/2006/main">
<cxn ang="3cd4">
<pos x="hc" y="t" />
</cxn>
<cxn ang="cd2">
<pos x="x1" y="y1" />
</cxn>
<cxn ang="cd4">
<pos x="x2" y="y2" />
</cxn>
<cxn ang="cd4">
<pos x="x3" y="y2" />
</cxn>
<cxn ang="0">
<pos x="x4" y="y1" />
</cxn>
</cxnLst>
<rect l="sx1" t="sy1" r="sx4" b="sy3" xmlns="http://schemas.openxmlformats.org/drawingml/2006/main" />
<pathLst xmlns="http://schemas.openxmlformats.org/drawingml/2006/main">
<path>
<moveTo>
<pt x="x1" y="y1" />
</moveTo>
<lnTo>
<pt x="sx2" y="sy1" />
</lnTo>
<lnTo>
<pt x="hc" y="t" />
</lnTo>
<lnTo>
<pt x="sx3" y="sy1" />
</lnTo>
<lnTo>
<pt x="x4" y="y1" />
</lnTo>
<lnTo>
<pt x="sx4" y="sy2" />
</lnTo>
<lnTo>
<pt x="x3" y="y2" />
</lnTo>
<lnTo>
<pt x="hc" y="sy3" />
</lnTo>
<lnTo>
<pt x="x2" y="y2" />
</lnTo>
<lnTo>
<pt x="sx1" y="sy2" />
</lnTo>
<close />
</path>
</pathLst>
we needed to extend our custom shapes for missing features and so 5
new segment commands were added. G command for arcto drawingml record
and H I J K commands for darken, darkenless, lighten, lightenless
records. the commands are save into ODF in special namespace drawooo,
which is extension not yet in the standard. Thorsten suggested to put
it in such a namespace and keep original (incomplete) geometry for
backward compatibility, before we can extend the ODF. that's why you
will see 2 of them in cases where some of the new commands was
needed.
In order to convert preset shapes to LO's enhanced custom shape,
we need to load shape definition of preset shapes. The procedure
to convert the definition from OOXML spec for LO is documented
in oox/source/drawingml/customshapes/README.md.
The oox/source/drawingml/customshapes/generate.sh script generate pptx
files for single presets and also for all presets
cshape-all.pptx. The cshape-all.pptx file is then loaded into Impress
build with debug enabled in oox and the command line output contains
information. The generated definition is oox-drawingml-cs-presets.
Check CustomShapeProperties::initializePresetDataMap() to see how
generated presets data are loaded into LO.
While importing presets, we prefix the name with "ooxml-" so
that we can detect it on export as save it again as preset.
The generated pptx files
can be used when debugging bugs in custom shapes import/export. also
the cshape-all.pptx can be used to test the round trips. there's small
problem with these pptx as they cannot be imported into powerpoint,
but that can be fixed quickly. when fixed, we can use it to
test powerpoint odp export and see how complete it is regarding
custom shapes. OpenXML SDK might help when fixing cshape-all.pptx
https://github.com/OfficeDev/Open-XML-SDK
Also, "OOXML Viewer VSCode Extension" is a useful tool for debugging OOXML documents.
https://github.com/yuenm18/ooxml-viewer-vscode
Export
Here is how LO's enhanced custom shapes are exported:
- Shape name is
ooxml-*- they are imported from ooxml, export as is. - Denylist - ODF presets that has OOXML equivalent. We convert adjustment values case by case. Microsoft Office is rather strict about adjustment values, either none of them are provided so that default values are taken, or the exact set of handles have to be provided. In some cases we are converting from the preset with less handles to the one with more handles so that default values suitable for the odf one need to be provided.
- Allowlist - ODF presets that has OOXML equivalent but looks a bit
different, export them as
PolyPolygon.
Check Andras Timar's presentation[1] and ShapeExport::WriteCustomShape()
for further detail.
Future Works
Because we have to make sure that all the roundtrips
like PPTX --> ODP --> PPTX work correctly and doesn't lose data.
the only problematic part is probably saving custom shapes (ie. not
presets) to PPTX. that part of code predates work on custom shapes
and is unable to export general custom shapes yet. It will need a bit
of work as LO has more complex equations than DrawingML. other parts
should work OK, PPTX --> ODP should work and don't lose any
data. presets should already survive PPTX --> ODP --> PPTX roundtrip