OK, I figured as much .... was curious because working in (think) latex is not overly expensive when using (LARP) weaponsgrade latex.
You are right, latex is pretty cheap actually, and I've been working with it already.
But there is several problems with latex:
1. You must include paint within liquid latex, you cannot paint it when dry and have a durable result. It makes painting more difficult, and major failure could mean you have to trash the mat and build a new one
2. Latex is sticky when dry, and stick to itself. You must coat it to avoid troubles; coating it is annoying because the only flexible/transparent coating I know is not flexible enough to build a mat you can roll. So I would need lot of prototyping to find the appropriate coat.
3. Latex will crack because of UV
4. Latex has a yelowish color when dry, this will alter the paint color
5. Some people are allergic to latex
So to build my mat I will have to do a lot of prototyping (could be expensive), probably to come to the conclusion that latex is not the right material, because most company selling flexible terrain/Scenery are NOT using latex.
I need a quicker and cheaper path
If you do a mat of the aforementioned size then I would put the wavy "sand-accumulations further apart. If you also put in other texture ? then I assume that would be more rocky/broken ground in appearance and you would see the wavy pattern gettin more compressed (waves more near to another) closer to the more "solid" pieces of your map.
I'm not sure to understand...
Do you mean that for a 180x120cm mat I should not use the wave pattern at all? What else then? Or do you mean I should mix it with other textures?
What I want to achieve is sun-burned sandy-desert, with dunes and half buried ruins.
Something like Soudan desert and its famous Meroe Pyramids:
