in fact my problem is not solved . it seems like the feedback effect happens everywhere but on the surface drawn by the shader .
i use a torus , in perspective wich has a shader applied .
i tried the following workaround(archive is joined ) , but still no luck . the file to open has a OPEN in name .
i would like the dots to have the feedback , or dots + geometry alltogether.
i tried pix_snap2tex ( using gems.feedback from pdmtl abstractions) too but no luck because we can't choose the mixing function . and i would like only white to make trails . and i don't know how to keep the supporting geometry from appearing . the torus should be full black with a white trail only .
btw i'm on windows not my choice. i have to share the screen with other programs wich are windows only
any help welcome once more .
Thanks
Pierre-Yves