[Scilab-users] hist3d() puzzling rendering

classic Classic list List threaded Threaded
4 messages Options
Samuel GOUGEON Samuel GOUGEON
Reply | Threaded
Open this post in threaded view
|

[Scilab-users] hist3d() puzzling rendering

Hello,

Using hist3d() -- just enter hist3d() to plot the example --, and rotating the figure in 3D (right-press and drag), we can note that the color of the different faces are not the same: 2 of the four faces are rendered with the hidden color (usually used for the internal or back faces), and the 2 other ones with the default or chosen color and color mode.

I was deeming that the usage of the hidden color for 2 over 4 apparent faces is a bug.

Now, i am wondering if it is not rather intentional, in order to have a kind of lighting effect.

I still think that, even if it was intentional, it should rather be fixed. Now, Scilab has some explicit lighting features.

But, before possibly processing the bug report, what's your opinion?

Samuel


_______________________________________________
users mailing list
[hidden email]
http://lists.scilab.org/mailman/listinfo/users
Rafael Guerra Rafael Guerra
Reply | Threaded
Open this post in threaded view
|

Re: hist3d() puzzling rendering

Hi,


Preserving the color of the original hidden faces under interactive rotations, does not seem to be a bad idea. It allows assessing what parts of the objects are hidden under the original choice of view angles.

The behaviour of plot3d is similar.


Regards,

Rafael



From: users <[hidden email]> on behalf of Samuel Gougeon <[hidden email]>
Sent: 15 June 2018 14:02
To: International users mailing list for Scilab.
Subject: [Scilab-users] hist3d() puzzling rendering
 

Hello,

Using hist3d() -- just enter hist3d() to plot the example --, and rotating the figure in 3D (right-press and drag), we can note that the color of the different faces are not the same: 2 of the four faces are rendered with the hidden color (usually used for the internal or back faces), and the 2 other ones with the default or chosen color and color mode.

I was deeming that the usage of the hidden color for 2 over 4 apparent faces is a bug.

Now, i am wondering if it is not rather intentional, in order to have a kind of lighting effect.

I still think that, even if it was intentional, it should rather be fixed. Now, Scilab has some explicit lighting features.

But, before possibly processing the bug report, what's your opinion?

Samuel


_______________________________________________
users mailing list
[hidden email]
http://lists.scilab.org/mailman/listinfo/users
Samuel GOUGEON Samuel GOUGEON
Reply | Threaded
Open this post in threaded view
|

Re: hist3d() puzzling rendering

Hello Rafael,

Le 17/06/2018 à 19:25, Rafael Guerra a écrit :

Hi,


Preserving the color of the original hidden faces under interactive rotations, does not seem to be a bad idea. It allows assessing what parts of the objects are hidden under the original choice of view angles.

The behaviour of plot3d is similar.


It's a plot3d() bug in 6.0, and hist3d() uses plot3d().
hist3d() had actually 2 bugs (not one). They are fixed @ https://codereview.scilab.org/20164

Samuel


_______________________________________________
users mailing list
[hidden email]
http://lists.scilab.org/mailman/listinfo/users
Samuel GOUGEON Samuel GOUGEON
Reply | Threaded
Open this post in threaded view
|

Re: hist3d() puzzling rendering

In reply to this post by Rafael Guerra
Le 17/06/2018 à 19:25, Rafael Guerra a écrit :

Hi,


Preserving the color of the original hidden faces under interactive rotations, does not seem to be a bad idea.


The bug was not that the color of some faces changed with respect to the view angle, but that the hidden color was wrongly ascribed to some external visible faces.
By the way, the way Scilab ascribes the hidden color looks not documented. It follows the "screw" rule to set the external and internal faces. So, the order vertices are provided matters. I did not see it described in any page.



_______________________________________________
users mailing list
[hidden email]
http://lists.scilab.org/mailman/listinfo/users