Blowing - Trees - 1280x720px page 6...

[ajcgi]

Wow there have really been some interesting experiments on these forums of late!

[otakar]

Very impressive work, Martin.

[bla bla 2]

Ca ne marche pas chez moi, je vois juste que ca change de vert plus clair au foncer. Je voudrais bien faire du vent.


It does not work at home, I just see that it will change from green light to darken. I would love to wind.

[TheBadger]

lol

Since this tread is up front again... I'm not to proud to beg, yet again.
Martin, Do you think there is a way to make your effect fit into a few nodes that anyone could just plug into their own network and get wind? Something like your grass and sand, where the user can make simple changes, in this case wind direction and speed? With the new partnership between planetside and the render farm I think doing animations with wind may be more practical now. What do you think?

[dandelO]

I don't think I can make it any easier to explain than I have here: http://forums.planetside.co.uk/index.php?topic=12191.msg124055#msg124055

As for making it into a few nodes that anyone can fit into a scene, really it is only 2 nodes that require pretty minimal editing. Simply add a power fractal, add a transform shader. Done.
Make sure the fractal is flat-scaled(2 octave) to suit the leaves of the tree(this is why you can't really make it fit all scenes, not everyone scales their scenes the same and a real scale wind effect wouldn't work on a(say) 10x model scale, that some packages export). I always use real scales and I'd encourage everyone else to as well. With all features of the fractal now being of randomly equal size, you now have a smooth noise to transform over time on any axis.

Really, once the fractal is created and the scales adjusted to all be '1', you never need to touch it again. The transform shader does everything. If you have a 10x scale tree, just enter '10' in the scale of the transform shader to rescale the wind to fit.
Scaling up by 10 means you should also scale up the wind speed, controlled by any of the 'translate' parameters, just multiply the translate value by 10.

MOST IMPORTANTLY: You can't use 'ray trace objects'.

I'll make a small example with a grass clump and upload later, busy just now.

[bla bla 2]

Peut-on voir dans le preview l'effet de vent ? Je pense que oui. 

Can we see in the preview the effect of wind? I think so.

[dandelO]

No, you won't see the wind in the 3D preview window, Bastien, it won't affect your wireframes.
You will see it in the 'shader preview' window for the leaf shader. To see it, set the projection method to 'through camera'. Remember to set it back to 'object UV' before rendering, though. You can see how it looks in the shader preview .gif that I added to the explanation on the previous page.

* I forgot to come back here with a grass clump example file, I'll do it shortly...

[dandelO]

Sorry for not getting back to this thread with an example sooner, I forgot.

I'm attaching the .tgd for this image;



I have left all the shaders in the main node network view for ease of access, if you make a new grass clump, the shader will be inside it and you should set the wind shader to it with a right-click on the 'displacement function and selecting the transform shader from the node list menu. (or, just create the shaders inside the grass clump node but you might want to use the wind nodes for more than one object, leaving it in the main node network makes it easier to find and apply to each model you like).

The power fractal is set to scales='1', you don't need to apply any displacement here, it won't have any effect.
The transform shader moves the fractal colour upwards(Y) by 5m over 50 frames.
The 'default shader' uses the transformed fractal colour as its 'displacement function'(value='1')

* To see the effect of the wind, open the 'shader preview' window for 'default shader 1'. I've set it to around 3m so we are quite close to the shader. Move the camera and then just advance through the frames, you will see the shader preview update in real time.

Download .tgd[attachimg=#]

[dandelO]

* You'll notice that the shadows don't react, there's nothing I can do about that, sorry, it's just the way of the program.

[PabloMack]

Thank you so much for your explanation, dandelO! I tested your method with MGebhart's first pack of Generic Pines (Nr. One)...and it worked very well. This model has alpha mapped images of needles and twigs on quite large billboards which move nicely and natural.

Hannes, I copied your two nodes into a scene where I am using XFrog's Adult Sequoia giganteum. I am not an Apple user so I did not pull down the generic pine. I scaled the X&Y Transforms so that the change per unit time is the same as what you have. The model I am using only has one needle part so I applied the Transform Shader to its displacement input. My trees are doing absolutely nothing detectable over time. I have spent most of the day on it and I am frustrated. But I have the water and clouds moving fine. I don't know why my Sequoia leaf parts are not moving.

One thing I noticed that was not talked about is that the color low (black) and color high (white) seem to define the range for the Power Fractal Output. Also, it would seem that the interpolation method should be set to Linear instead of TCB in the Transform Shader since any point you begin "observing" the clip is an arbitrary point in a continuous process.

[attach=1]

[Oshyan]

Are you either A: disabling Raytrace Objects (RTO), OR using the new (in Terragen 3) Mesh Displacer Input?

- Oshyan

[PabloMack]

Are you either A: disabling Raytrace Objects (RTO), OR using the new (in Terragen 3) Mesh Displacer Input?

I disabled the RTO in the Render Panel and Whaaaaooooooh.....The tree looks burned to a crisp and three buckets are rendered such that they look zoomed in on some foliage. But the foliage now moves.

[attach=1]

Is this Mesh Displacer a new input to an existing node or is it a new node type? I do not see such an input on the Sequoia Needle part node. Where is it supposed to be?

[Oshyan]

So now your displacement is probably too extreme (with RTO off), but at least it's getting results now. Raytrace Objects does *not* allow displacement at present, and since the technique described in this thread relies on displacing objects to work, you have to turn off RTO to get it to work.

The new Mesh Displacer is an input on each *Object* node (not in the internal shader network/parts shader/etc.). Because it is an input to the Object, it operates on the object as a whole, so you can't only move 1 part, for example leaves animated without trunk being oddly distorted. But it *does* work with RTO turned on. Look in an Object node on the Mesh tab...

- Oshyan

[PabloMack]

I have copied the two nodes that were plugged into the Displacement Input on the Needle Part node and these are now input to the Object Population Mesh Displacement Input (which is the only input to that node type). I am now rendering the second frame with Ray Trace enabled. It looks very promising. There is a noticable difference between frame 1 and frame 31. I plan to set up an animation render while I'm off to visit with family. Thanks so much for the help.

I can see the challenge that TG is going to experience in creating a "Wind Input" into Object nodes if they ever decide to do one. Starting at the root, the further from the root the part is the more it can sway and twist. There is a sort of continuous Parent-Child relationship along the connection of a plant from the root to the distal-most parts (leaves). Without an explicit skeleton, each model will have to be analyzed for its skeletal structure. Its not going to be easy.

[PabloMack]

In case anyone is interested, I achieved close to the subtle look I was shooting for. I used the Mesh Displacement input of the population node that Oshyan was suggesting. Since it works with Ray-tracing, I think it is the way to go. I have yet to test it with shadows, though, but it should work.

http://www.youtube.com/watch?v=7Z7V_orPbIA