Hey Everyone,

I was trying out viewsheds for the first time to create shadows for terrain rendering. I managed to get everything working; however, I noticed that the observer point has to be on the surface. This was creating issues for me as the shadows would be cast in different directions. I imagine that grossly expanding the surface would be an adequate workaround; however, it seems rather clunky and unnecessary.

Is there any way to modify the code to allow for observer points to be outside the bounds of the raster?

Thanks!

Attachments:
No Shadows.JPG
Shadows.JPG

That's a really great effect! For observer points outside the raster, I'd just make the raster bigger, with the additional regions being nodata/null values in pixels.

Adding to what Dimitri is saying: you can make an image bigger simply by editing its Rect property.

Thanks Guys, These suggestions worked; however, I will attest that it does feel unnecessary to do so. For anyone else reading this, edit the Rect property as Adam suggested, then run the following code.

TABLE CALL TileFillBaseLevel([SURFACE]);

UPDATE [SURFACE] SET [Tile] = CASTV(TileMake(128, 128, NULL) AS FLOAT32) WHERE [TILE] IS NULL

Oooh nice. Two different meanings of "NULL" in one query!

Making NULL orthogonal to itself? Not really.

What the UPDATE query means, in plain English, is: "Replace each tile (within the scope of Rect) which is currently NULL, with a non-NULL tile made up of NULL pixels."

(OK, somewhat plain English.)