texture and blending

dear list,

i'm trying to build a patch which basically emualtes a karaoke-like
coloring of a text in given time segments. my approach is to display
the text in several jit.gl.text3d objects (generated out of a xml
file in a javascript object) and doing the coloring via a moving
texture on a plane (jit.gl.gridshape, blend_mode 2 4), lying on top
of the scene. my problem is that this seems only to work when the
jit.gl.gridshape object is instantiated _after_ the text objects,
which is a problem as i generate text objects anew all the time.

any thoughts on this? find the isolated problem in the patch below.

also, i'm not shure if my general approach is a very clever one, i
still have problems with positioning the various text objects in
relation to each other (as they can't output their size). until now i
use a workaround where every new text object gets rendered in an
offscreen matrix once and measured with jit.findbounds... dirty and
works only approximately. more thoughts?

any help/comments/ideas appreciated!
thanks, chris