### Author Topic: Plane simple  (Read 366 times)

#### N-drju

• Member
• Posts: 1231
• A ship in port is safe... well, fine by me.
##### Plane simple
« on: November 07, 2017, 12:21:36 PM »
I have to admit I was very reluctant to use the native plane object in TG. Until yesterday.

I used warped SSS to create a river bed and then thought this way... If I want to have some water flowing through an approximately 10km piece of river, putting a lake "water circle" over the entire area would be a major waste of time. As you may probably know, TG is processing water shader regardless of whether it's above or below the ground... So instead of putting lake object and seeing most of its surface going to waste, increasing my render time, I decided to try out the plane object. It turned out a very clever decision it was.

You can really cut down on water shader coverage and the final render time (in case of rivers especially) by putting a plane object in a desired position and simply outfitting it with a water shader as a texture. This way you can save up on the water surface coverage that goes to waste and is not even visible (but rendered nonetheless) under the terrain. Anyway, consider the images and values below. Numbers speak for themselves:

Keep in mind that the plane object only renders the surface which is within the parallelogram denoted by "orange" and "magenta" edges. It does not render the entire "bounding box" area contrary to the lake object. In general, you can really economize on the water coverage when plane object is in use. The gains and difference are even higher if your water bodies are very thin, like streams or rivers.

There are only two evident limitations to this method that i can think of. First of all, plane objects does not take into account the planet rounding. When you spread a plane object over 100km, you will notice that the edges of the plane shader will be higher above the ground than the center of it. Therefore, plane objects outfitted with water shader are no good over huge areas.

Another tricky thing is the rotation and tilting of plane objects. The plane object uses so called "vectors" which is something completely different from degrees which we know and love. But this is also the reason why you can create a parallelogram out of the plane object instead of a simple square or circle... It might be tricky at first. But when you get the gist of it, it should cause you no trouble at all.

Just my two cents on the plane objects. May well work as an alternative and cheaper lake object.

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Updated the second image. An even better shape is possible.
« Last Edit: November 07, 2017, 12:47:32 PM by N-drju »