Support tileOrigin for all Grid layers.

[tschaub]

In r11002, support was added for a tileExtent property. This was a quick fix to make gridded layers work with cached tile sets with a lattice that doesn't align with the layer's maxExtent property. However, the "bottom left" assumption is still baked in (the lattice is aligned with the bottom left of the tileExtent or maxExtent). This still doesn't work for all tile caches.

The proper way to support tile caches with our gridded layers is to support a tileOrigin property. It also makes sense to pull out the "bottom left" assumption into a property that other layers can override.

To avoid overlapping property proliferation, and because the behavior with tileExtent is not really adequate (we also still request tiles outside the tileExtent), I'd like to remove that property and only add tileOrigin to the API.

[tschaub]

support tileOrigin for Grid layers

[ahocevar]

I am in favor of this change. In case you meant to set this ticket's state to "Review", I'd set it "Commit" now.

[tschaub]

Great, thanks. I did mean to set it to Review status. I wanted to get feedback about how it worked in a few environments first. Got that feedback, and I think it is working as expected. Thanks for the review.

[tschaub]

Closed with r11033.