## gl2 vs gl3: single plane matrix to gl.slab

Oct 29 2020 | 4:13 am

Hi,
I've sometimes fed a float32 one-plane matrix to a jit.gl.slab. My reasoning was that it would save some data duplication to avoid a conversion to a 4-plane matrix.
It turns out that this doesn't work anymore with gl3: the one-plane matrix is then treated as a red plane.
I could just convert my matrices to 4-plane (jit.pack or jit.matrix)
But would someone point me in the right direction to massage the gl3 version of the shader in order to let the GPU use a single plane input on the internal RGB or RGBA?
Here is a simple example working in gl2, but not in gl3.

Thanks!