## Mutliples in Terragen?

Started by WAS, October 25, 2018, 08:38:26 pm

#### Dune

##### October 30, 2018, 02:50:41 am #30
No, but does that save on rendertime? It works the same way, but there's no compute terrain anyway, just the difference between get altitude and displacement to scalar....

#### mhaze

##### October 30, 2018, 05:47:14 am #31 Last Edit: October 30, 2018, 07:14:09 am by mhaze
Here's an example using get altitude, slightly easier to mask but harder to set up. I've added a redirect to add to the fun.

#### Matt

##### October 30, 2018, 03:23:43 pm #32 Last Edit: October 30, 2018, 03:25:50 pm by Matt
If you had a lot more terrain shaders in there, then yes, the number of times they are calculated substantially affects the render time (for the same reason that Compute Terrain affects render time). Moreover, someone might follow this whole setup by a Compute Terrain, so you want it to be efficient. Your Displacement to Scalar should be replaced with Get Altitude and its input disconnected. I believe it will produce the same output, but more efficiently.
Just because milk is white doesn't mean that clouds are made of milk.

#### Dune

##### October 31, 2018, 02:43:28 am #33
Thanks Matt. I wouldn't have thought the difference between get altitude (a calculation, afaik) and displacement to scalar (a calculation) would be that big, but it's good to know.

#### Oshyan

##### October 31, 2018, 04:53:25 pm #34 Last Edit: October 31, 2018, 11:54:55 pm by Oshyan
Different calculations have different levels of complexity and thus calculation time. This goes down to even the simplest of calculations, for example addition and subtraction are faster in CPUs than multiplication. Both are "calculations", but one takes more resources/time.

- Oshyan

#### Matt

##### October 31, 2018, 08:20:37 pm #35
Displacement to Scalar calculates the tree of nodes input to the Displacement to Scalar (i.e. the fractal in your example, which has hundreds of instructions), while Get Altitude simply reads the displacement that was already in memory and calculates its altitude (which is just one vector subtraction and one dot product).
Just because milk is white doesn't mean that clouds are made of milk.

#### Dune

##### November 01, 2018, 03:15:37 am #36
Thanks, guys. Learned something again!

#### WAS

##### November 01, 2018, 03:10:07 pm #37
Found this digging on the forums by Frank, could be of help with different types of terracing.

https://planetside.co.uk/forums/index.php/topic,13221.0.html
Check out my Terragen Discord: https://discord.gg/Vy5FRTE

#### WAS

##### November 02, 2018, 02:47:54 am #38
Quote from: WASasquatch on October 25, 2018, 08:38:26 pm
Is it possible to do a conditional to check multiples? Ex ( altitude / scalar ) != 0

Additionally have it recursive for height? From like 0 - alt or alt - 0

What I was thinking of doesn't provide me anything
Check out my Terragen Discord: https://discord.gg/Vy5FRTE