Keeping objects (TGLSphere, TGLLines) appearance

[LefjuCabro]

Hello GLScene's users,

I am a new user of GLScene and I am impress of these capabilities. However I got some problems for using it correctly...

In my case I want to zoom in/out into my scene and keeping objects appearances. With MouseWheel event I can zoom in/out into my scene with AdjustDistanceToTarget but the objects (TGLSphere, TGLLines) increased/decreased. For example, in my GLSceneViewer, spheres have radius of 0.1 and when I zoom in/out I want to keep this aspect.

Is there any method or do I scan all objects and modify each radius (for TGLSphere) and lineWidth (for TGLLines) ?

Thanks for your advices.

Regards

[Jerome.D (BeanzMaster)]

Hi what do you want to exactl ? this comportment is normal, if you are near an object is bigger, it's normal you are in 3D not in 2D. Explain more you want exactly.

[LefjuCabro]

Hi Jerome,

I understand that we are in 3D so objects are bigger when we approach an object, no matter with that.

But in my case I don't want enlarged objects when I zoom in. I want them to keep original radius appearance. For example, original sphere radius is 0.1. When I mouse wheel up, radius is still 0.1 but I have to decrease this radius in order to have same sphere appearance as the original.

Regards

[Jerome.D (BeanzMaster)]

This behaviour is not recommended if you want see object that not scaling use a sprite via TGLHud and set position. but on each time you zoom you can try to call this for each object :

procedure UpdateObject(myobject:TGLSceneObject;constantzoomfactor:single=5.0);
var
  d: Single;
  v: TVector;
  I: Integer;
begin
    d := Viewer.Camera.distanceTo(myobject) / constantzoomfactor;  
   // View referer a.k.a the parent of myobject   
  // myobject.Direction := FUIBaseGizmo.Direction;
  // myobject.Up := FUIBaseGizmo.Up;

   if myobject.Visible then
     myobject.Scale.AsVector := VectorMake(d, d, d);
end;

but for 500 is not fair. If you want make a soft in 3D but showing something in 2D use ortho perspective it will be better or you must use a 2D solution and use sprites instead.
what you want to search to do exactly ? what is your project ?

[LefjuCabro]

Hi,

My soft is a meshing tool: users build a mesh ( = a physical structure) by creating spheres and lines.
I want to keep 3D because users could move around the structure.

Attached some screenshots of application that inspired my project: spheres in Init and ZoomIn have same radius.

[Jerome.D (BeanzMaster)]

Hi ok see the attachement file here : https://sourceforge.net/p/glscene/discussion/93606/thread/07e2548f/#f7dc
and look at meshdata part. for line instead of using TGLine you can use Outline Shader

[Pavel Vassiliev]

Jerome,
Have a look at my private message to you about preparing the next release
PW