RE: TCONS problems.

Valery Fine (fine@bnl.gov)
Sat, 5 Jun 1999 20:38:02 -0400

>
> Hi Rooters,
>
> this macro is an excerpt from g2root *.C ouput. It draws a part of
> CDF muon system.
>
> running this macro with root v2_21_06 produces wrong output
> (attached gif file 'old.gif'). With the root version v2_22_00
> result is fine (attached file 'new.gif').
>
> Is it a problem with v2_21_06 in general? Or our root version v2_21_06
> is corrupted (I have the same problem with v2_21_08 though).
>
> {
> TRotMatrix *rot12496 = new TRotMatrix("rot12496","rot12496",90,0,90,90,180,0);
> TCONS *CMXA = new TCONS("CMXA","CMXA","void",104.14,564,625,381,442,311.75,228.25);
> TNode* Node1439 = new TNode("CMXA1","CMXA1",CMXA,0,0,-454.66,rot12496);
> Node1439->cd();
> Node1439->Draw();
> }
>
> I'd be happy if you could hint on how to fix this using 'old' root
> version since transition to v2_22_## will not happen soon here.
there was a bug with TCONS ctor definition, namely the order of the parameters doesn't match with
those from GEANT,

ROOT 2.22
========
TCONS(Text_t *name, Text_t *title, Text_t *material, Float_t dz, Float_t rmin1, Float_t rmax1,
Float_t rmin2, Float_t rmax2, Float_t phi1, Float_t phi2);

TCONS(Text_t *name, Text_t *title, Text_t *material, Float_t rmax1, Float_t dz
, Float_t phi1, Float_t phi2, Float_t rmax2 = 0);

ROOT > 2.22
========
TCONS(Text_t *name, Text_t *title, Text_t *material, Float_t rmin1, Float_t rmax1,
Float_t rmin2, Float_t rmax2, Float_t dz, Float_t phi1,
Float_t phi2);

As one may realize the 4th parameter was "Float_t rmin1" and 8th parameter was "Float_t dz"
The new version has made it in line with GEANT docs and g2root code as well, namely:

the 4th parameter is "Float_t dz" and
the 8th parameter is "Float_t rmax2"

So to use OLD ROOT one has to moved that 4th parameter (which is a real "dz"
value but "rmin1") to 8th place where the "old" ROOT expects it to see.

TCONS *CMXA = new TCONS("CMXA","CMXA","void",104.14, 564, 625,381, 442, 311.75,228.25);
TCONS *CMXA = new TCONS("CMXA","CMXA","void", 564, 625,381, 442, 104.14, 311.75,228.25);

But you should not forget to move it back just you will switch to > 2.22 version
of ROOT in future.

Hope this helps
Valery

PS. PARA shapes should be drawn fine as well (compare the output of the tutorials/shapes.C
macro done with "old" and new" ROOT versions.