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problem with ISession_Text

MAIRE's picture


I have problems with ISession_Text class in a V3d_Viewer. I cannot :
- change color
- modify type of alignment
- change scale, width, height ...

Every change has no effect !!!
Thank you for answer.

Jendrik Seiler's picture

In case anyone stumbles across this thread in the future with the same problem: I was able to fix the color changing by adding the following line to the ISession_Text.cpp file:

void ISession_Text::Compute(const Handle(PrsMgr_PresentationManager3d)& aPresentationManager,
const Handle(Prs3d_Presentation)& aPresentation,
const Standard_Integer aMode)
myDrawer->TextAspect()->SetColor(this->myOwnColor); // This one
Prs3d_Text::Draw(aPresentation,myDrawer,MyText,gp_Pnt( MyX ,MyY,MyZ ));

I had to include the following files as well

#include "Prs3d_TextAspect.hxx"

but now it works just fine.

Jendrik Seiler's picture

I added a few more lines of code:

myDrawer->TextAspect()->SetColor(this->myOwnColor); // color does not change otherwise
if(this->MyScale != 0) { myDrawer->TextAspect()->SetHeight(this->MyScale); } // size does not change otherwise
myDrawer->TextAspect()->SetFont("Rock"); // size resets font

Possible font types are "Times-Roman", "Times-Bold", "Times-Italic", "Times-BoldItalic", "Courier", "ZapfChancery-MediumItalic", "Rock", "Symbol", "Iris" and "ZapfDingbats"

Also, any time the ISession_Text is removed and redisplayed in the viewer I have to call the Redisplay() function or the properties reset.

Hope this helps someone at some point.