kicad-developers team mailing list archive

[Mário Luzeiro <mrluzeiro@xxxxx>]

> I suspect one day I might create a Write() for the model parsers so that I can
> improve the VRML export. In such a case I would also eliminate the Transforms;
> for me there is no point in maintaining transforms unless we support the reuse
> of coordinate lists and vertex indices. At the moment the presence of transforms
> only increases processing time of the VRML file.

> - Cirilo

Hi Cirilo,

In my point of view, transforms in models are good and bad. I disagree (for rendering proposes) that transforms increase processing. Well, it will make the things easier to code while dealing now with openGL (scale, rotation, translation). So it make the things at this point easier.
But.. it will make things harder if we need to know the real value (absolute) for (as I refer before) calculate bounding box or other aspects from the model, because it will need to apply all the transformations with C math (as opposite to use openGL math functions) to get that vertices transformed and processed in CPU.

I don't know much about the VRML exporter. I notice that it in some part is just adding an URL/Link to an external file (for the VRML format) (so how it is apply transformation in that case?)
but I see that it is transforming all vertex in x3d (by the way.. I that feature must be checked to see if I didn't broke anything related with this latest additions)
I do believe for exporter it will be also easier to use transformation commands (scale, rotation, translation) .. expecting that the external 3d software will support it.

In the best world, transforms are good it will add flexibility as you suggest to support reuse ("USE" tag in VRML) of models but for full support it will need some coding work.

As a KiCad user, if I don't want use exporter for CAD proposes but just for rendering proposes, then, I may prefer other file format model than VRML (maybe x3d or something more wide support .. as OBJ.. ) and just hard raw mesh (just vertex, materials, colors ... ) ... one single file.. but at same time, it will be usefull if we can keep the objects model separated in order if you want to add different materials.. textures while rendering in a external software.

Regards,
Mario Luzeiro