Specular light in the Geometry package

ROOT
1

Hello,

I would like not to see the specular color when using the Geometry package with OpenGL.
Is there any way to see only the ambient and diffuse colors?

Thanks,
Luciano

2

Hello, I do not know the “direct” ROOT solution. However, with the Coin3D ROOT plugin it should be quite trivial (yes, in this case one needs to install Coin3D too )

See the star.bnl.gov/STAR/comp/vis/S … 6.2006.ppt
Slide 13.

The Coin3D plugin is included into the binary distribution for Windows. So it should take you about 5 min to install (from root.bnl.gov/QtRoot/downloads/root.5.14.00.exe ) and try the example shown on Slide 13 to play with the material properties. For example, you can merely save your 3D scene in Coin3D text format, edit that text file, and play it back.

Let me know whether you are interesting? (I am busy this week. Next week I can create another example to show how to play with the material properties). I did not reply via the Public Forum, because it is still under construction. Please, communicate me via my E-mail lists.bnl.gov/mailman/listinfo/qt-root-l

3

[quote]Hello,

I would like not to see the specular color when using the Geometry package with OpenGL.
Is there any way to see only the ambient and diffuse colors?

Thanks,
Luciano[/quote]

Hello. Right now the only way is to change these components using GUI for each object :frowning: I think we can simply add what you want into viewer’s GUI.

4

As Timur said, this is something trivial to add to the standard ROOt GL viewer.

I strongly encourage you to not follow the Valeri Fine’s advice to use Coin3D
and is dependency suite. This is a dead-end that will create more problems that it will solve in the short and medium term.

Rene

5

Brrr, :open_mouth: I really did no mean to send this out. I missed I pushed “submit” button :blush:

Frankly, I am really impressed :exclamation: with ROOT team courage, energy and qualification those allow them successfully build the “Coin3D” / “Open Inventor” kind of the system.

On the other hands I would like to mention the whole 3D viewer ROOT plug-in project was initiated by Rene Brun’s advice. It is no way compete with the current ROOT development (it is just Plug-in, i.e. another implementation of the existing ROOT abstract interface.). It is to complement :bulb: it.

This means, if you are happy with what the vanilla ROOT provides, then of course you do not need seeking any other tool. However, the nice ROOT design does allow (there are very few systems of the ROOT scale around providing anything alike) to complement your the system with the third party solutions also.

Since, we at STAR, have not enough man-power to get what STAR need right now, we did ask the summer student from Dubna to do this plug-in. He did it, spending 1.5 months at BNL.

Which combination should be applied for the one’s concrete task is really one’s “business solution”.

6

[quote=“brun”]I strongly encourage you to not follow the Valeri Fine’s advice to use Coin3D
and is dependency suite.[/quote]It seems to me I did not advice to use it because I am not aware about the scope and scale of the task in question, did I? I have no idea whether it worth using Coin3D for one’s application.

Should I understand your remark like you do see the STAR plug-in as a competitor of the current ROOT development? Believe me, it is wrong perception. There is neither ground nor man-power no reason nor will to do that.

7

Valeri,

I simply want to avoid user complaints in this forum (as much as possible)

Rene

8

[quote]Hello,

I would like not to see the specular color when using the Geometry package with OpenGL.
Is there any way to see only the ambient and diffuse colors?

Thanks,
Luciano
[/quote]

Hello, Luciano.

There are several ways:

  1. You can take CVS head - it contains changes in GUI to add control element to turn on/off specular light component (it’s in a gl-viewer’s GUI, in the ‘Style’ tab, it’s name is “Specular light”). The best way.

  2. If you cannot update your ROOT and cannot recompile your ROOT - you can turn off front light - it’s the only light source that has white specular component in our gl-viewer. Yes, picture will be dark and you have to rotate it to find good POV. :slight_smile: So, this my suggestion is not very usefull :slight_smile:

  3. If you do not want to update your ROOT, but can modify and recompile - you can comment the line
    glMaterialfv(GL_FRONT, GL_SPECULAR, fColor + 8);
    in TGLPhysicalShape.cxx and recompile. This is a hack :slight_smile: