confusing dr3d:lighting-mode

[Regina Henschel]

Hi all,

in ODF 1.2 exists the attribute
19.99 dr3d:lighting-mode

It has the description
"The dr3d:lighting-mode attribute specifies whether lighting is used in 
a three-dimensional chart." and "... a three-dimensional scene."

And for data type: "The dr3d:lighting-mode attribute has the data type 
boolean 18.3.3."

What is the purpose of this attribute? From the text I would expect, 
that it enables/disables the use of lights in the scene or chart.



But in addition exists in ODF 1.2 for 3D Objects the style property 
20.79 dr3d:lighting-mode

The description is, "The dr3d:lighting-mode attribute specifies whether 
lighting is used for a three-dimensional object."
Notice the "three-dimensional object" here.

And for data type: "The defined values for the dr3d:lighting-mode 
attribute are:
     ●double-sided: the front and back sides of all planes are displayed 
if they are visible from the viewer's perspective.
     ●standard: Depending on the value of the dr3d:normals-direction 
attribute, only the front or only the back side sides of the plane are 
displayed. The opposite sides are not displayed, whether they are 
visible from the viewer's perspective or not."

So this style property is connected to normals.



The code is very confusing. I find in mbLightingMode(false) in 
SdXML3DSceneAttributesHelper and later 
setPropertyValue("D3DSceneTwoSidedLighting", uno::Any(mbLightingMode))
That makes no sense to me.

I do not find any place where "double-sided" vs "standard" is evaluated 
on file open, I see no UI element to set it, and the property 
"D3DDoubleSided", which sounds so, is mapped to XML_BACKFACE_CULLING in 
sdpropls.cxx, which is another different style property. And my test 
files do not work as I expect it in regard to normals, in case I write 
dr3d:lighting-mode="standard" in the file.


Reason for my investigation is, that the OASIS ODF TC will revise these 
texts for ODF1.3.

Kind regards
Regina