[JesperW]

Before I spend a billion CPU hours I thought I'd ask for some tips. I want to create a reasonable sea surface. It should reflect the sky, and and also refract stuff under the surface.

This is how far I got in PhotoWorks:



Some issues:

The horizon needs a very large plane. I have this modelled as a large plate in SolidWorks now, and use PhotoWorks depth que to hide the edge behind the visible horizon.

Also I have a bottom of the sea, that I'd like to refract through the surface together with the keel of the yacht, but that needs so many level of refraction using PhotoWorks Advanced Dielectric shader that rendering takes a lifetime.

I got Maxwell today, and have achieved nice results already. But as I said, any input on how to model the sea surface as CPU-efficiently as possible would be appreciated!

Also, the waves are a bumpmap jpeg. As I understand from the video tutorials the way to get a bump map into Maxwell is by assigning it as a texture in SW. Only the SW Texture command does not allow me to select an arbitrary bitmap, just the SW standard ones. How do I get this jpeg to be the bumpmap of my surface then?

/jesper

[JesperW]

I had missed the SolidWorks "File Locations" setting where I can set a custom texture library. Sorry about that.
/j

[JesperW]

So this is what it looks like:



A few problems:

The weird banding looks like the renderer is only using the bump map for some polygons of the body, not all. The material is assigned to the entire body!

The SW texture mapping is limited, for example the U,V-size of the map cannot be set numerically. On a very large surface like this I had to make the bitmap VERY large (5000x5000 pixels) to get the correct size of the waves. Is there no way to specify the U,V mapping for the renderer separate from SW's?

Or if I could make the body used for the surface smaller. But I need the horizon to be closer then. I tried the Maxwell Fog setting, to see if I could reduce the visibility distance, but that only produces totally black renders. Do I need a separate emitter for rendering fog? The Plugin still has "Enable Sunlight" selected, but "Sky" disabled, so one would think there would be sun+fog = some light?

/j

[juan]

Hello Jesper,

The weird banding looks like the renderer is only using the bump map for some polygons of the body, not all. The material is assigned to the entire body!

If the material is assigned to the entire body indeed, then it could be a bug of maxwell. Usually the scenes with big bumps take more time than others, may be you get less weird pictures with more render time.

The SW texture mapping is limited,... Is there no way to specify the U,V mapping for the renderer separate from SW's?

In the future Maxwell will provide more tools to improve the texture handling. Also SW will be more powerfull in this area in next releases.

I tried the Maxwell Fog setting, to see if I could reduce the visibility distance, but that only produces totally black renders. Do I need a separate emitter for rendering fog? The Plugin still has "Enable Sunlight" selected, but "Sky" disabled, so one would think there would be sun+fog = some light?

The fog do not work properly in the current version of Maxwell. It will be fixed in the release of October. Also when you disable the physical sky there is no sun even if you enable the "sun light field".

I suggest you to use a emitter map (MXI texture) to get a hiperealistic sky (even a map for the water). You can find a lot of info in this forum about MXI and HDRI textures. Also one of the swmaxwell videotutorials explains how you can apply one MXI texture to an emitter in SolidWorks.

If you have more questions please let me know.

Cheers,

Juan

[JesperW]

OK, the fog will have to wait then

The banding is certainly a bug. I don't know if its the plugin translator or the renderer, though.

I have made the sea surface much smaller, so I can also use a much smaller texture. I also made it rectangular. This is the result:



This is what is happening: Every other tile of the bumpmap texture works, and every other is ignored. The border corresponds exactly to the border between tiles in SW (I know this because my bumpmap doesn't tile perfectly seamlessly

The face is just one square planar face.

Tell me if this is a plugin or renderer bug, I'll post it in the main bug forum if it belongs there.
/j

[juan]

It seems it is a bug in maxwell, not in the plugin, so I suggest you to post it in the bug reports forum. In some cases bump maps do not work properly, in other cases everything runs fine. We have solved a lot of things in this area and you will see amazing improvements soon.
Anyway the bump uses to work in swmaxwell, here I post you an example. Pay attention that in both cases the material applyed to the box is the same in all the parameters except that in the first case the difuse channel is enabled and in the second case the bump channel is enabled.




Specially you have to be care about one thing when you are handling maps: when you create a material with any map enabled, assign it only to bodies with the same SW texture applyed. DO not apply this material to bodies without textures or with other SW textures. For example if the waves and the ship have assigned the same maxwell diffuse material with the bum channel enabled, and the waves have one SW texture applyed but the ship has not, it will give you undesired (and sometimes unpredictable!) results. In this case you need to have one material for each object.


Yours,

Juan

[JesperW]

I thought I'd share som success as well, not just bugs



(OK, I admit, I have converted the model to 3DS and made all the material assignments in 3DS since the SolidWorks plugin is not really production ready, but anyway... I'm pretty impressed myself)

[piroshki]

Jesper,

Sorry, I tried to follow what happened, but didn't quite follow...

You original question was how do you model the sea efficiently. i'm using Rhino, and have the same questions:

- how do you model a sea that goes to the horizon?

- could you suggest a source for a good sea bitmap?

- are render times atrocious?

P.

[parel]

Would you look at that! niice leap from the PWx render

[JesperW]

Well, I guess I asked the original question because of my experience from PhotoWorks and MentalRay, where the sea surface is the main cause of long rendering times. (Using a "real" sea surface, a reflective and refractive surface with a wave bumpmap).

It seems for Maxwell this is not the case at all. In fact my rendering times with or without the sea element are approximatly the same....

It just shows that Maxwell has a totally different architecture, and that there are other things that are more important for the rendering performance.

/j

[JesperW]

Oh, and your other questions, piroshki:

A sea that goes to the horizon: Make it *really really* large
Mine is 5000 meters. Problem is in real life the sea is not flat, which means that a rendered flat surface will look weird (The earth is round, remember In reality visible surface distance is only about 2000 meter for a 2m above sealevel eye position.

I use the Maxwell Z channel output to create an image mask, and then paste the mased image onto a photographed sea background. It is really quick and easy.

I did my bitmap in photoshop, using a combination of the waves and noise filters, and a lot of scaling, warping and hand editing.

Define atrocious I find my resource cost (my time + cpu time) to achieve the same quality results with Maxwell as with 3DS renderer are less. I spend four times the CPU time (during which I can do other work!) and about 10% of the setup time. In 3DS or PhotoWorks I had to adjust light and material parameters every time I changed the camera angle, and do a few test renderings. In Maxwell I click "Physical Sky", "Sunlight", "Render". Takes less than 1 sec, instead of 1 hour setup before I could even *start*...

/j