Applying specific colors to a p5.Geometry

I have made a sphere using new p5.Geometry()

geometry = new p5.Geometry(definition, definition, ellipsoid);
renderer.createBuffers(gId, geometry);
renderer.drawBuffersScaled(gId, radiusX, radiusY, radiusZ);

I would like to be able to apply what ever color I want to each face of the sphere
My goal is to draw a little planet with its elevation map and apply colors according to the elevation

I have already done one version WITHOUT new p5.Geometry using the command vertex() but i imagine new p5.Geometry() could give me more flexibility and power.

Can you help me ?