Automatic projected mapping script request

[narrator]

I have an idea of a great script but am unable to create one myself.
I often achieve great results in sketchup by not creating geometry but using an image projected on a surface - great for urban models with roads and vegetation.

workflow>

1. go to top view (parallel projection) and zoom to see the full extent of your surface
2. prepare a horizontal rectagnle so that your surface fits inside (~ bounding box top side)
3. make a parallel projected top view image of your surface
4. use 2d editor to cut out the 'bounding' rectangle from this image and save it
5. import this 'bounding' rectangle image file (as an image)
6. place this image exactly over the rectangle
7. explode image
8. 'sample paint' tool click on the exploded image
9. 'paint bucket' tool click on the surface

is it possible to create a script which could automate any/all steps?
easier version would be enough - to create a blank (white) image with the dimensions of a surface bounding box and apply this image as a projected material

thanks for your answers! if somebody could provide a rough sketch of the script I would try and make one

[narrator]

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