Thanks for the various answers .... First I downloaded MeshLab and tried to create a cube and color it ... actually OSG colors it well and I'm happy with that.
However, the problem arises when I attach a texture to a face. In fact, the .mtl file is created and this is managed as a material and then everything returns as before and OSG fails not knowing how to manage it .... My need is to import complex .obj models (boats) containing a lot of textures .... Il giorno mercoledì 28 settembre 2022 alle 07:13:35 UTC+2 [email protected] ha scritto: > Yes, you are right! > > I knew also vertex colors are supported but wasn't sure if that was in the > 'v' or separate parameter. It's been a while since I worked with it, and I > think most of the Editors supports it when dealing with point clouds, not > sure for 3D models > > On Tue, Sep 27, 2022 at 9:43 PM [email protected] < > [email protected]> wrote: > >> Trajce, >> >> The way I read it, they can't use materials to colour their object. >> >> OSG's .OBJ reader supports vertex colours when written like this: >> >> v -7.941349983215332 -11.136899948120117 -3.4483699798583984 1.0 >> 0.0 0.0 >> >> with the last three values here being the red, the green and the blue. >> >> This works at least with the text version of .OBJ files. If the user has >> actually access to the .mtl file, your approach is fine. This vertex colour >> approach here is an alternative, although, as I understand, it's not >> totally supported by 3d graphics editors. >> >> - Vaillancourt >> >> On Tuesday, September 27, 2022 at 2:14:51 p.m. UTC-4 >> [email protected] wrote: >> >>> Hi, >>> >>> obj does support colouring by using mtl (material) associated text file >>> where materials are defined with all the color and texture info in it. if >>> the obj is text (not binary) you can set your material to be used per face >>> for example in text editor - for binary you are left to your modelling >>> software. And the osg obj loader uses the mtl file if present - from real >>> cases with obj from Blender you might need to adjust some color properties >>> in text editor >>> >>> On Tue, Sep 27, 2022 at 8:42 PM [email protected] < >>> [email protected]> wrote: >>> >>>> Hello Marco(?) >>>> >>>> Although wavefront .obj don't support vertex colours out of the box, it >>>> appears the OSG obj plugin code can read vertex colours the way MeshLab >>>> outputs it. I'm not sure how it's done, but I would give it a try. >>>> >>>> >>>> On Tuesday, September 27, 2022 at 10:23:50 a.m. UTC-4 >>>> [email protected] wrote: >>>> >>>>> Hi, >>>>> >>>>> if I can't use material to color the model loaded from obj file, now >>>>> how can I color that model avoiding to use shaders? >>>>> >>>>> >>>>> >>>>> Thanks >>>>> >>>> -- >>>> You received this message because you are subscribed to the Google >>>> Groups "OpenSceneGraph Users" group. >>>> To unsubscribe from this group and stop receiving emails from it, send >>>> an email to [email protected]. >>>> To view this discussion on the web visit >>>> https://groups.google.com/d/msgid/osg-users/c4473ca3-286e-4c9d-8a9f-4870af61f197n%40googlegroups.com >>>> >>>> <https://groups.google.com/d/msgid/osg-users/c4473ca3-286e-4c9d-8a9f-4870af61f197n%40googlegroups.com?utm_medium=email&utm_source=footer> >>>> . >>>> >>> >>> >>> -- >>> trajce nikolov nick >>> >> -- >> You received this message because you are subscribed to the Google Groups >> "OpenSceneGraph Users" group. >> To unsubscribe from this group and stop receiving emails from it, send an >> email to [email protected]. >> > To view this discussion on the web visit >> https://groups.google.com/d/msgid/osg-users/909a77b0-5159-4cc3-93a0-44039fecc91bn%40googlegroups.com >> >> <https://groups.google.com/d/msgid/osg-users/909a77b0-5159-4cc3-93a0-44039fecc91bn%40googlegroups.com?utm_medium=email&utm_source=footer> >> . >> > > > -- > trajce nikolov nick > -- You received this message because you are subscribed to the Google Groups "OpenSceneGraph Users" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To view this discussion on the web visit https://groups.google.com/d/msgid/osg-users/48e34a18-14bf-4db1-a084-16cc6304d4b6n%40googlegroups.com.
