Applying Shaders to Polygons

I’m trying to apply a stripe effect to some polygons. The default stripe generator works fine, but the stripes move with the camera, or rather are not fixed to the polygon as it moves across the screen.

Applying my own simple shader https://goo.gl/o3atmf or using a bitmap fill comes out as distorted, with the stripes being compressed and wonky.

Does anyone know of anyway round this? I basically want to fix the stripes to the polygon’s local space rather than the screen coordinates. For bonus points I want adjacent polygons to have their stripes correctly line up!

Are these made by display.newPolygon (), or display.newRect () / display.newImageRect () followed by changing the path corners?

They are made by display.newPolygon

Hmm, weird. Is the bitmap fill a regular image or a frame from an image sheet?

Just a regular image 

Are these made by display.newPolygon (), or display.newRect () / display.newImageRect () followed by changing the path corners?

They are made by display.newPolygon

Hmm, weird. Is the bitmap fill a regular image or a frame from an image sheet?

Just a regular image