through the surface

[gasbutan]

Has anyone ever tried to produce an image like this in Terragen ?
I tried different techniques using just the lake, a plane or a card, or even a cube with a glass shader for the water.

Thx

[Dune]

Lake, plane, card sphere would all work, I'd expect (as they could have no shadow), with a glass shader (maybe doublesided?), but you didn't succeed?

[WAS]

Well you actually reminded me I have a test I wanted to whenever I got ability to animate which is a displaced plane with glass shader for a underwater effect like you got going on here. I never did do anything with it. Did it a long time ago when doing a underwater scene with some fish cards.

[gasbutan]

Thank you, Dune for your recommendations.

Here are some test renders:

1. Lake


2. Plane


3. Cube (camera inside the cube)



All objects have a glass shader with double sided ON.

[WAS]

Thank you, Dune for your recommendations.

Here are some test renders:

1. Lake


2. Plane


3. Cube (camera inside the cube)



All objects have a glass shader with double sided ON.

This is quite interesting. Plane seems to provide the best effect though is it me or is the object parts being individually displaced?

[Dune]

I did a little test yesterday, and found that lake doesn't work properly, but an inverted plane (or sphere) does. I also set glass shader to single-sided and an inverted decay distance. Some reeds in water, some palms on shore, which can both be seen.
I must say, I find the reflection of the trout (courtesy of Doug Campbell) rather vague (though that vagueness was better visible without all the reeds).
Path tracer nicely blurs everything above water, this is a standard render.

[gasbutan]

@WAS:  yes, the plane shows the strongest effect. Nevertheless it is not what I expected.

@Dune:  Wow, this really looks good. Thank you, I will try this setup.

[Hannes]

I did a little test yesterday, and found that lake doesn't work properly, but an inverted plane (or sphere) does. I also set glass shader to single-sided and an inverted decay distance

Wow, that's smart! Cool, Ulco.

[WAS]

I did a little test yesterday, and found that lake doesn't work properly, but an inverted plane (or sphere) does. I also set glass shader to single-sided and an inverted decay distance. Some reeds in water, some palms on shore, which can both be seen.
I must say, I find the reflection of the trout (courtesy of Doug Campbell) rather vague (though that vagueness was better visible without all the reeds).
Path tracer nicely blurs everything above water, this is a standard render.

Perhaps a secondary reflection surface without heightlights would help bring out the under-side reflections. I seem to recall you suggestion this method before with just the water surface plane to give it a better "watery look". Cool to see it in action. Pretty sure that's where I tried a plane for the camera and warping the whole scene (like underwater stuff in games).

[gasbutan]

It works, great!
Thanks for the assistance !

Underside reflections are an interesting challenge. It would be interesting how to manage total internal reflection effects.
The surface close to the camera should be transparent, whereas parts of the surface at a greater distance should be reflective.
I think I have to start some research....

[Dune]

You could use a distance mask to set further away to just reflection and close-by to transparent. That is what I often do in topdown water scenes to decrease rendertime. I don't know if the glass shader would take care of that itself. Water shader might, but I'm not sure actually.

[gasbutan]

Distance mask is a good idea. I will try that.
On the othe hand it doesn't only depend on the distance but on the angle between lightray and the surface, and this might change with the waves. So you will have a transition between transparency and reflection...

[Matt]

Proper refraction and internal reflection should work if the surface normal is facing upwards and the camera is below it. Displaceable surfaces like Plane and Lake aren't visible like this because of back-face culling (at the time of writing, v4.4), but the non-displaceable Card should work with a rotation of -90 on X. Then you don't need to fake the reflectivity, it'll be physically correct internal reflection.

[WAS]

Proper refraction and internal reflection should work if the surface normal is facing upwards and the camera is below it. Displaceable surfaces like Plane and Lake aren't visible like this because of back-face culling (at the time of writing, v4.4), but the non-displaceable Card should work with a rotation of -90 on X. Then you don't need to fake the reflectivity, it'll be physically correct internal reflection.

Ohh, that means a few of my old underwater scenes should work fine. I was using just a card with water, though would need to disable the secondary card for shadows.

[gasbutan]

Thank you, Matt for the valuable note. I will experiment with this settings.