Animation with hierarchical structure


I have got a problem that I think it will be very easy to solve for you.

I have got a hierarchical structure like grandfather, father and son (All of them as TopoDS_Shape). To get that, I have created a compoundSon (with son), compoundFather (with father and compoundSon) and compoundGrandFather (with grandFather and compoundFather).

Doing that, I save those compounds, and I wait for a user input.

I need to translate the grandfather, and rotate parent a son.

My problem is that I don't know why.

Animation sample gives a clue: "Transform AIS_Shape and you will get it"

gp_Trsf trans;
trans.SetTranslation(gp_Vec(x, y, z));
myAISContext->SetLocation(aisGrandFather, trans);

It works, but I don't have aisFather and aisSon. If I create them, I get duplicated objects, of course. This method don't allow me to manage all the objects tree.

Trying with another method, I can't get results.

gp_Trsf trans;
trans.SetTranslation(gp_Vec(x, y, z));
TopLoc_Location toploc_location(trans);


If this last method could work, I will apply other gp_Trsf to the other compunds.
Nothing gets translated so, are there a sentence missing? Have I forgotten something?

If I have to replan all, please tell me why I should do it.

Thank you very much.

arkoala's picture

Ok, my TopoDS_Compound gets translated, even with this code:

gp_Trsf trans;
trans.SetTranslation(gp_Vec(x, y, z));
TopLoc_Location tpTrans(trans);

or this one

gp_Trsf trans;
trans.SetTranslation(gp_Vec(x, y, z));
BRepBuilderAPI_Transform trsf (trans);
TopoDS_Shape result = trsf.Shape();
if (result.ShapeType() == TopAbs_COMPOUND)
compoundGrandFather= TopoDS::Compound(result);

I know it because if I create a new AIS_Shape and display it, I realize that compound has been translated.

So my original problem is not how to translate, but how to bound my AIS_Shape with the new compound translated or how to refresh AIS_Shape in the viewer.

I thought both objects were linked, and with "myAISContext->UpdateCurrentViewer();" instruction was enough.

Thanks in advance.

arkoala's picture

Unique way to get my goal I found is:

myAISContext->Remove(aisMachine, Standard_False());
aisMachine= new AIS_Shape(machineAll);
myAISContext->Display(aisMachine, Standard_False);

I remove the aisObject and recreate again. I think this method will have a poor performance, and not only that, it flickers a lot.

Resolved (I think in a bad way) compoundGrandFather translation. I make the same to rotate compoundFather and I get no results :(

I think it is a simple task: To animate a typical 5X machine.
Please, I pray for any hint. A valid hint is to tell me it is impossible.

I am getting crazy with this problem...

nberron's picture


Your topic helped me to understand how to translate a TopoDS_Shape and its associated AIS_Shape.
However, recreating the AIS_Shape was not acceptable for my needs, so I looked a bit forward, and found the following solution:

// Translate the TopoDS_Shape
gp_Trsf tsf;
tsf.SetTranslation ( gp_Vec ( iX,iY,iZ ) );
topoDS_Shape.Move ( TopLoc_Location ( tsf ) );
// Update AIS_Shape whith the 2 following lines:
hAIS_Shape->Set ( topoDS_Shape );
hAIS_Shape->Redisplay( Standard_True );

Hope it will help you if you did not find any way since you wrote this topic

Have a good day,

Nicolas Berron