Support of Flip expressions in dynamic blocks.

[mme1950]

We are trying to read dynamic blocks with Flip operations.
Flip operations apply to a state of the dynamic block. We need to extract the "normal" and the "flipped" version of the state.

I think for this purpose it should be sufficient to read evaluation expression of these types

• BLOCKFLIPPARAMETER
• BLOCKFLIPACTION

Respective classes can be set up as

public class BlockFlipParameter : Block2PtParameter {
}

public class BlockFlipAction : BlockAction {
}

I implemented readers and templates for

• BlockFlipAction
• BlockAction
• BlockFlipParameter
• Block2PtParameter

These evaluation expressions are successfully read and referenced by the state of the dynamic block. This is nice but it is half the job,

To extract the flipped version of the dynamic-block State we have to apply the flip operation to the entities listed in the BlockFlipAction object, i. e. we must mirror all coordinates of the entities at the line defined by the two XYZs provided by the BlockFlipParameter object. Texts, however, must not be mirrored, but the angle and alginment has to be changed.

@DomCR Do you have a suggestion how to include such functionality into ACadSharp?

[DomCR]

Hi @mme1950,

I started working on a Transform utility to make this kind of operations:

• Geometric transform #457

The idea was that the user can apply a transformation matrix into any entity.
This feature can be extended for the different BlockAction so they generate their own transformation matrix and apply the transformation into the entities in the block.

Note: the mirroring of the text shouldn't be a problem I think is controlled by TextMirrorFlag.

[mme1950]

Hi @DomCR,
this is really great, Thank, you.