Topic: Block scaling

[latour_g]

Hi, can someone explain me why scaling block that have been mirror doesn't work well ?
Here is an example.  On the right, it's the original block, on the left, it's a mirror of the block on the right.

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BlockReference br = (BlockReference)tr.GetObject(id, OpenMode.ForWrite);
Matrix3d m3d;
m3d = Matrix3d.Scaling(4, br.Position);
br.TransformBy(m3d);


[WILL HATCH]

You'll need to show the part of your code with the error in it  this part looks fine

[latour_g]

I would like to but it's really only that in my code ! (with of course the traditionnal using (Transaction ...) and dispose, commit after)

[dgorsman]

I think mirror is implemented as a negative scale in one of the axes (check the axis scale values for the block reference).  Not sure about the transform process, but if it assumes applying a positive scale in all axes then any previous mirror will be nullified.

[MexicanCustard]

Have you tried using the BlockReference.ScaleFactors instead of using a transformation?

[latour_g]

Thanks dgorsman, you are right !
Well sorry Will, I realize that my snippet code was not complete. 
It's

Code: [Select]

m3d = Matrix3d.Scaling(((lRatio) ? nScale * br.ScaleFactors.X: nDwgScale / br.ScaleFactors.X), br.Position);instead of

Code: [Select]

m3d = Matrix3d.Scaling(4, br.Position); 
I wanted to make it look more simple 

So with that, everything is working fine now.  Thanks you guys !!

Code: [Select]

BlockReference br = (BlockReference)tr.GetObject(id, OpenMode.ForWrite);
Matrix3d m3d;
double nScaleX = br.ScaleFactors.X;
if (nScaleX < 0) nScaleX = -nScaleX;
m3d = Matrix3d.Scaling(((lRatio) ? nScale * nScaleX : nDwgScale / nScaleX), br.Position);
br.TransformBy(m3d);

[WILL HATCH]

awesome