Well, the code looks working for me for a simple shape:
std::vector<gp_Pnt> m_vVertexes = {
gp_Pnt(0,0,0),
gp_Pnt(10,0,0),
gp_Pnt(10,10,0)
};
Make sure to call V3d_View::FitAll() to fit the scene.
Archived discussion
Displaying a Face in 2D
Hello all,
When set in a 2D view (View->SetProj(V3d_Zpos)), what is the best topology to display a shape? It sounds like a weird question, bear with me...
I have a setup whereby the user can create (2D) shape outlines using AIS_Point() and AIS_Line(). When the shape is closed, I'm creating an AIS_ColoredShape() from the outline, but its not being displayed.
In particular, I'm trying to do this via a Face - but not sure if this the best medium to use, as I can't get it to close?
Not sure whether its the non-closing face which is causing the problem, or simply the AIS_Shape() doesn't want to display in a Z-down view?
Any thoughts, code below?...
Author
{
unsigned i;
gp_Pnt p1, p2;
TopoDS_Wire aWire;
TopoDS_Face aFace;
BRepBuilderAPI_MakeWire mkWire;
BRepBuilderAPI_MakePolygon aPoly;
//--------------create polygon from stored points-------------------
for(i=0; i<m_vVertexes.size(); i++)
{
p1.SetX(m_vVertexes[i].X());
p1.SetY(m_vVertexes[i].Y());
aPoly.Add(p1);
}
aPoly.Close();
aWire = aPoly.Wire();
//--------------create face from polygon-------------------------
gp_Pln aPln(gp::XOY());
aFace = BRepBuilderAPI_MakeFace(aPln, aWire);
#ifdef _DEBUG
qDebug() << "Face Closed: " << aFace.Closed(); //SHOWS FALSE
#endif
//-------------create AIS shape to display----------------------
Handle(AIS_ColoredShape) myAIS_Shape = new AIS_ColoredShape(aFace);
myAIS_Shape->SetColor(Quantity_Color(Quantity_NOC_DEEPSKYBLUE1));
m_AIScontext->Display(myAIS_Shape, true);
//NOTHING SHOWN
}
Discussion
3 archived replies
Posts are displayed in their archived order.
How very odd. Thanks for checking, at least I know where not to look!
As my points and lines are showing up fine, I'm wondering two things...
1. I've got a problem with my view setup (defaulting to displaying lines but not faces)?
2. Unexpected transparency on the face
Weirdly, select detection of the face works when I click it, it just isn't visible.
Difficult to pull all the setup together in one place, but does this look any different to your setup?...
Handle(Aspect_DisplayConnection) aDisp = new Aspect_DisplayConnection();
Handle(OpenGl_GraphicDriver) aDriver = new OpenGl_GraphicDriver (aDisp, false);
// lets QOpenGLWidget to manage buffer swap
aDriver->ChangeOptions().buffersNoSwap = true;
// don't write into alpha channel
aDriver->ChangeOptions().buffersOpaqueAlpha = true;
// offscreen FBOs should be always used
aDriver->ChangeOptions().useSystemBuffer = false;
// create viewer
myViewer = new V3d_Viewer (aDriver);
myViewer->SetDefaultBackgroundColor (Quantity_NOC_IVORY);
myViewer->SetDefaultLights();
myViewer->SetLightOn();
myView = myViewer->CreateView();
myView->SetImmediateUpdate (false);
// create AIS context
myContext = new AIS_InteractiveContext (myViewer);
if (is2DWindow)
{
myViewer->ActivateGrid (Aspect_GT_Rectangular, Aspect_GDM_Lines);
myGrid = myViewer->Grid();
myGrid->SetColors(Quantity_NOC_GREEN1, Quantity_NOC_GREEN3);
//turn off 3D controls
AIS_ViewController::SetAllowRotation(false);
AIS_ViewController::SetAllowPanning (true);
AIS_ViewController::SetAllowZooming(true);
//set camera to top-down facing
myView->SetProj(V3d_Zpos);
myView->Zoom(-100,-100,+100,+100);
}
Solved!
Missing a line from the display setup:
myContext->SetDisplayMode(AIS_Shaded, Standard_False);
Thanks!