Slow Rendering

[edward]

Feathers in general are a very tough problem, and especially if you want them to be animatible. They had a paper about modeling and rendering realistic feathers this past siggraph:

http://online.cs.nps.navy.mil/DistanceEduc...entation03.html

Hope that helps or perhaps gives you some ideas.

[cs00bren]

hello there you could try getting a realistic picture of a feather. Then in photoshop change it in to a black and white image of the out line. then in houdini using the trace SOP to create a perfect out line of the feather. then all you need to do is texture it with the original feather to create a good model.

once you have this you can then play around with it apply a bump map and other stuff.

i looked at your model and i thought it looked v.good i can wait to see the finished version.

bren

[thrasherstudios77]

I want to thank everyone again for the continued ideas and support

edward- I checked out the Siggraph link it was very interesting and helpful. I don't know to much about recursive penetration detection in Houdini, I get the idea and using Maya dynamics and MEL scripting I could probably figure something out, but Hscript in Houdini is a total mysterey don't know where to start. But the link did give me some cool ideas, shoot just the pictures alone helped me out. Thanx

cs00bren- i had thought out doing my feathers some what the way you described but using the trace SOP seems a hell of alot easier.

Here is another idea I had for makin' and helping me to animate the feathers of the wings. I was going to make a horizontal spline curve in the shape of a wing. Feed the spline into a Copy SOP and the second input of the COPY sop I would feed the feather shape. Basically I am hopeing to place a feather at every breakpoint, or vertices along the curve. I figure I can keep the feathers from penetrating each other by tweaking the curve so from one vertices to the next would by behind each other layered. Don't know if that made sense. Here is a picture of what I am thinking about. I have tried this method in Houdini and can't get the COPy sop to copy the feathers to the curve points, Ill keep trying though. Any more ideas on modeling and animating feathers are welcome

Mahalo

Benjamin

[thrasherstudios77]

Here is the image

[edward]

Perhaps something like this? (I mean for the diagram above).

copied_circles.zip

[TheUsualAlex]

But then how do you deal with the feather intersection...?

Wasn't that the huge problem that SPI overcame in Stuart Little 2?

[thrasherstudios77]

edward- thanks for the file I will check it out

Alex- Do you know how they over came the penetration problems on Stuart Little 2, do you know a link that maybe describes how?

[old school]

I would guess that rendering is your problem. Are you rendering with subdivisions set in the object's render folder Geometry option? If you are, turn that off and see the result. If you aren't and you don't know about this, use it as it subdivides the geometry further at the micro-polygon level at render time. As a matter of fact, if you aren't using creases and are relying on a final subdivide SOP to get smoothness (which I suspect you are doing by setting it to 3), then you can just set the display on this one then the render flag one above this to get the same, no make that, 1000% better effecct as there is no cooking overhead and no memory overhead in generating the .ifd scene. Memory bloat happens at render time and since the render micorpolygonizes everything anyway, no overhead. Use this feature, render as "subdivision surfaces" with polys if you can.

Try rendering out just an .ifd and see how long that takes. To do this, go to the mantra output driver and where you see "Generate Script File", turn that on and provide a file name, something like ./testbird$F.ifd . If that takes a long time, then there is a problem with cooking the scene. If it is fast to generate the .ifd, then your problem is in the renderer.

Now, if you are familiar with using a c-shell, you can open up the houdini c-shell, source in the houdini environment then go to that directory and try:

mantra < testbird1.ifd

This will pass the ifd file to mantra to render the image. If this takes a long time, your problem is with mantra. If you don't know how to use shells, well if you want to be an SFX TD with Houdini, you basically have no choice IMHO to get at the guts of stuff quickly.

Now do you fuse the two pieces together as one solid piece of geometry?

[thrasherstudios77]

old school- Thank you for the information, I actually with help from many people on this forum have the eagle rendering out at about 17 seconds which is fine. Basically just use the Mantra output option "Optimized Polygon Rendering", and just use the sub-divide SOP for viewing the eagle in the viewport, the render flag is set to the last edit SOP in the network

I have another question though, I applied a simple Vex Gallery Marble to the eagle through SHOPs and the render took like 20 minutes. Is this pretty standard with Mantra renders. In other programs applying a simple procedual shader only takes the renderer about 5-10% longer if that, but I am finding with Mantra that it is increasing the render time by 5000%,

or eagle with no shader 17 seconds with shader 20 minutes roughly.

I deleted history on my SOPs network down to the last edit SOP and the render took the same amout of time What is going on here. Would I get a faster render if I actually built a Marble shader in VEX, meaning does SHOPs somehow slow down the renderer. But i am thinking that it doesn't because the Gallery Marble shader is a VEX shader. Is there a way to stream line SHOPs shaders to make them faster to render?

Thanx in advance