iterate slices of the volume / load iterated slices into volume

[Jonathhhan]

hi,
i iterate slices of the volume with a shader for a game of life app.
i loop the slices of the volume, which works well. the only thing is that it hangs for one frame at the end of the volume / loop.
perhaps because there is a background fbo for the last slice of the volume (actually the first and the last slice of the 3d texture is not shown)?

second question: is it possible to load the shader output back into the volume without passing the data to the cpu (with ofPixels)?
this is the uploading part of my code:

...
a.gameOfLifeFbo:beginFbo();
ofClear(0);
ofDrawRectangle(0, 0, a.volWidth, a.volHeight);
a.gameOfLifeFbo:endFbo();
a.gameOfLifeFbo:readToPixels(a.gameOfLifePixels);
a.gameOfLifeShader:endShader();
a.texture3d:loadVolumeData(a.gameOfLifePixels:getData(), a.volWidth, a.volHeight, 1, 0, 0, a.depthCounter);
a.gameOfLifePixels:clear();
...

kind regards, jonathan