How to Mirror a 2D symbol with the SDK as with the mirror tool?

[Nebeor]

I made some progress: But i'm not quite there, i changed the object variables like this:

TVariableBlock value =  TVariableBlock ((Sint16) 3);
gSDK->SetObjectVariable(*rect,  ovSymbolScaleType,value);
TVariableBlock value2 =  TVariableBlock ((Real64) -1.0);
gSDK->SetObjectVariable(*rect,  ovSymbolYScaleFactor,value2);

this does almost what I want, but unfortunately this does not work with the rectangle objects that are in my group.

I suppose this is a bug?
Apparently I need to 'Flip' this object without scale.
I'm looking forward to your reply.

Edited June 11, 2019 by Nebeor

[Nebeor]

apparently using scale on VWTransform is the way to go, It will keep everything 2D as long the z offset equals 0.

[Nicolas Goutte]

10 minutes ago, Nebeor said:

apparently using scale on VWTransform is the way to go, It will keep everything 2D as long the z offset equals 0.

 

Using a transform matrix was what I was about to recommend, but I was unsure for a 2D-Symbol, especially in VW 2015. (However, sorry, I had no time to test it, even on a newer VW.)

[JBenghiat]

Scale has nothing to do with mirroring, either with the object variables or the transformation matrix. 

 

A mirror is a flip of the transformation matrix and an offset from the line of reflection (twice the vector from the object to the reflection axis)

 

Using matrix transformations can be a bit tricky: you can get and set an object’s transformation matrix directly, which is its location and rotation in space, as well as transform by a matrix (effectively multiply the object’s matrix by the transformation matrix). The order of applying the transformation also makes a difference

 

VWTransformationMatrix also has a method returning whether a matrix is flipped. 

[Nebeor]

I think the use of matrices is the only sensible way to transform objects.(sorry Vectorscript and Python)

The good part now is that I can use almost the same transform for my 2D and 3D parts (hybrid objects),

I just have to drop the Z-offfset back to 0 on the transform before applying it to the 2D part.