Yay!

There's some texture 'banding' at the extreme angle in the corner, but decreasing the shading rate a bit more (I used 0.4 for this) should sort that out. I never use texture filtering anyway - it's never done anything good for me, so I have a single-click button that turns it off everywhere.

And so to bed... thanks again to all!

PS: Ooh, I nearly missed something back there... Geomatic hey? When? When?

"If I were a shadow, I know I wouldn't like to be half of what I should be."
Mr Otsuka, the old black tomcat in Kafka on the Shore (Haruki Murakami)