particle trees, mapped particles, particle flow and vray

[joconnell]

okay there's a few things here,

First of all if you use particle flow, it'll possibly kill your copy of max because of memory overhead. I'd make maybe four trees in total using whatever method you want, and then change them into vray proxy objects - what this does is makes external mesh files that vray loads at render time - they're more efficient than meshes in scene so they'll render with less memory and better speed.

I'd personally make a few different types of trees, make proxy objects and then place them by hand in the areas you want. There is a blurscript available on www.scriptspot.com called ranom transform that will randomly scale, rotate and move the currently selected objects so you can use this to make the trees look a little more randomly sized and placed so your scene will look more natural.

Stay away from leaves that are a single polygon with an opacity map on them. My company is currently working on a scene using trees and vray and for pal resolution with global illumination and camera motion blur, the scenes with 4.5 million polygons, no vray proxy objects and trees that have opacity mapped leaves, its going as high as 7 hours a frame.

Vray is very very efficient with polygons and geometry so I'd definitely try and use a tree that uses geometry for its leaves instead of a single poly with opacity maps.

Also check out the official vray forum, there's a tonne of people doing arch vis projects so they have done this type of thing a good few times before and can probably give you a lot of advice on what mistakes to avoid. http://www.chaosgroup.com/forum/phpBB2/

Hope this helps :)

[humfrez]

thanks for tips, thats the rather time costly way but i know it works at least, thats pretty mych what i did in the attached image above.

btw. those palms there have no texture "just" 30000 polys each - and they are vraymeshes so they render veeeeery fast, but i had to place them manualy.

my problem is that id like some kind of a method to do the placing automaticaly across a surface, vertices. etc so id like more procedural control over the number of trees, density and so on. but vraymeshes cant be used as particles unfortunately :( thats why im looking for a workaround.

is there a way how to replace each particle with an object but keeping the transforms ?

[charleyc]

While I am not certain that it is possible to emmit VRayProxies with PFlow, this script will allow you to replace all particles with a Picked object. I would use the method you described to 'paint' the geometry with your desired plant locations using a grayscale value (like all white were you want a plant type to be, and the rest black). In the Position Object operator, there is an option to use Material. Get your particles where you want them and run the script to place the VRayProxies. Adjust the 'paint' for your new location and re-run the script with a different object.

It is worth noting that while this script is based on having the PFSource selected and picking your distribution object, it could very easily be modified to have a selection of distribution objects selected, and Pick the PFSource and have the multiple distribution objects randomly placed throughout the flow.

Also, the script uses all the transform information from the particle, which includes rotation and scale, this makes it easy to add subtle variation to your plants.

www.charleycarlat.com/MaxScripts/RplceParts-w-Objs.ms (http://www.charleycarlat.com/MaxScripts/RplceParts-w-Objs.ms)

[humfrez]

this sounds like the perfect thing ! thanks a lot, im going to try the script right away :)

[humfrez]

thanks againg charleyc, works perfect as described.

i read the script lines, but i lack the script knowledge to add multiple distribution objects to be used randomly.

If anybody skilled enough in scripting reads this, and would spare some time to modify charleyc's script to do a random replace of several distrib object, id bemost thankful

i think it would be a very nice and usefull script for others to use as well.

thanks

[charleyc]

I updated the script, it has the same name, so just re-download it from the link above. Let me know if it works.

This time you will have a selection of objects and then run the script and Pick your PFSource.

[humfrez]

YES, works perfectly. thanks again. i guess i will look have a look at max scripting, to do at least the very basic stuff myself.

[charleyc]

I would recommend it. It doesn't take long to get a pretty basic understanding and while you may never create too many awe-inspriring scripts, it can save a ton of time at work.

[dprgb]

Stay away from leaves that are a single polygon with an opacity map on them. My company is currently working on a scene using trees and vray and for pal resolution with global illumination and camera motion blur, the scenes with 4.5 million polygons, no vray proxy objects and trees that have opacity mapped leaves, its going as high as 7 hours a frame.


Did you disable bitmap filtering on the leaf alpha channels? Having filtering enabled on the alphas can increase the rendering time, if it's disabled (no filtering) it should render faster.

[CGTalk Moderation]

This thread has been automatically closed as it remained inactive for 12 months. If you wish to continue the discussion, please create a new thread in the appropriate forum.