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Ivy?

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DEElekgolo interpolator
What is a good way to get some nice looking ivy grow off of my models? I tried ivy generator but it is always ridiculously high poly.

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  • mikebart
    hey DEElekgolo,
    A good way is to render from HP models onto a plane, but you can do it in photoshop too with some good refs. Just make sure you have a good variety of clusters for different situations.
    this models a bit dated now so you might want to use more polys and smaller clusters.

    projectionkv1.th.jpg plantsivy01dsd1.th.jpg

    Study some photos when you arange them onto the building

    ivyphotods8.th.jpg DSC04623.th.jpg

    I also used a tilable texture with just stems, criss crossing to help bond the leaves visually onto the surface, it just follows the shape of the structure.

    wireframe02fk6.th.jpg wireframe01px0.th.jpg

    overall i think there ended up being about only 400 tris, cant remember exactly, but it worked pretty well ingame.

    wip02fn4.th.jpg
  • DEElekgolo
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    DEElekgolo interpolator
    Wow thanks! I wouldn't have thought of that. May I ask what you used when making your high poly mesh? I would use Ivy generator but its branches and leaves aren't really the kind I would use as bitmaps. And it is very hard to control how the ivy grows...
  • Tumerboy
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    Tumerboy polycounter lvl 16
    you can make it by hand fairly easily.

    Draw out splines in the shapes you want the vines to grow, then loft another shape (circles usually) along that to get the basic branches. Make up a leaf or 3, and clone them along the path, rotate a few to get some variation, etc.
  • mikebart
    the ivy was modeled in 3dsmax, i used the line tool to make the stems and just cut the leaves out of a sheet of photos of ivy leaves i made in PS.
    The HP models also have diffuse, specular and a bumpmap on the material, so that when you render them to texture you just render each map seperatly, I also set up a few lights for baked in shadows.

    As far as controlling how the Ivy grows goes, just study some good refs, if you cant find them online go out and take some photos yourself, note things like; large ivy leaves usually are weighted and hang downwards, while smaller leaves on outstretching stems, can be angled in any direction because they're lighter.
  • Ben Apuna
    That's some nice ivy mikebart, thanks for the sharing your workflow :)
  • NoisyMonk
  • Mark Dygert
    NoisyMonk wrote: »
    There is also the stand alone ivy generator for people not using 3dsmax.

    http://graphics.uni-konstanz.de/~luft/ivy_generator/

    Both are insanely high poly, hard to bake down with the leaves, I don't think RTT takes opacity into account? So if you do this, do only the vines and put the leaves on separately in PhotoShop.
  • EarthQuake
    Vig wrote: »
    Both are insanely high poly, hard to bake down with the leaves, I don't think RTT takes opacity into account? So if you do this, do only the vines and put the leaves on separately in PhotoShop.

    I managed to get this to work at one point in max, i dont have any idea how i did it now, but it can be done.

    Oh here we go, i wrote up a bit of a tutorial here:

    http://boards.polycount.net/showthread.php?t=54178
    EarthQuake wrote: »
    Sure, first off i think it was MikeBart who i first saw do this, i'm pretty sure thats where i got the idea, been meaning to do it for quite some time now.

    Most of the work is done using this awesome free app: http://graphics.uni-konstanz.de/~luft/ivy_generator/ I generated a few variations here and exported them, and then did the following:

    1. Arranged each variation in a single file for easy baking

    2. Modifidied the normal map that comes with the base content a little, otherwise i used the textures you can download on that website.

    3. Set up a scene in max, with the alpha applied and the normal map applied(to get the small details to bake. I added sub-division to the branch geometry because it comes out a little jagged.

    4. Followed the tutorial here: http://www.bencloward.com/tutorials_normal_maps11.shtml for setting up a special scene to render normals, red/green/blue light thing. That turned out to provide a pretty good normals map from just doing a standard scanline render with an ortho camera.
    I used the method because i was having problems getting the alphas to work correctly using render to texture.


    5. Applied the diffuse textures and set the materials to self-illum, and deleted the lights so i could render out just the diffuse textures with no lighting. And then also did a render with the leaves white and the branches black to get a mask, to make for easily editing the different materials later.

    6. Set up a scene using lighttracer in the same way you would if you were doing RTT for ambocc.

    7. Composited all the diffuse/ao etc stuff in ps, tweaking/color correcting and adding color variation.

    Heres a pic showing the final diffuse map, and then the various textures that were baked.

    leaveprocessdh8.jpg

    This was a pretty good experiment, it ended up a bit flatter than i would like, i think it would be cool to maybe do a few layers of this stuff, maybe a branch layer, and then a few variations of a 3-4 leaves that i pile on top to build up some depth, so i may try to do that sometime too. As it is now i added a simple hieght map and threw on some parrallax to give it a little bit more depth, that seems to have worked. Gotta see how it looks from player perspective on monday =D

    Just looking back at it all, you can see mike's handy work doing all of it manually really pays off and produces a great result, but i think what i came up with was ok if you're short on time.
  • mikebart
    Yeah, that's pretty much how I'm loding my trees now, I've been working on a tree foliage tutorial that refers to Ben's technique, I've finished part one which outlines the highpoly side of things, part 2 will cover loding (which is where Bens technique comes in), there are just a few things im not sure about and want to improve before i finish it off but I just haven't gotten around to picking it up again, but i will soon.

    Anyway, this might help if you want to build the ivy by hand:
    http://www.armaholic.com/forums.php?m=posts&q=5197&n=last#bottom
  • Uly
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    Uly polycounter lvl 15
    had a go at some ivy recently, wrote up a lil' tutorial for it. this method wont work everywhere, but it worked for my scene.

    final result can be seen here: http://microwavetower.blogspot.com/2011/03/jstoutbcpage01.html

    and here's the tutorial:
    BC_screens_foliage01.jpg
    BC_screens_foliage02.jpg
    BC_screens_foliage03.jpg
    BC_screens_foliage04.jpg
    BC_screens_foliage05.jpg
    BC_screens_foliage06.jpg
  • PogoP
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    PogoP polycounter lvl 10
    Amazing tutorial Uly, thanks so much.
  • Tumerboy
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    Tumerboy polycounter lvl 16
    Nice Tut Uly! I dig your method. I alway try to cut out the leaves and reposition them. Never thought about just selecting the ones I wanted and leaving them there. . . (duh)
  • Shogun3d
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    Shogun3d polycounter lvl 12
    Interesting, let me get this clear, so essentially you cover the enture diffuse with an ivy texture, and carry your 3 different alpha variations within the RGB and plug them in for 3 materials? Indeed this is a great way to save on memory and also allow for variation instead of a full dif with alpha channel.
  • Uly
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    Uly polycounter lvl 15
    thanks guys

    Kaburan: Not in this case, no. What you see in Step 3 is pretty much the final diffuse texture. (on the far right.) Reason being this ivy needed vines to connect to the leaves, cause it was a relatively sparse configuration. If the whole thing was covered in Ivy, you would see many leaves over where your vines would be in the mask.

    The diffuse is a very dense collection of ivy, however. What I do with my alternative masks is mask out excess leaves and ivy, for a more sparse configuration when I need it. Or having the leaves bunch up on one particular side if it's growing in at a corner.

    What you're suggesting could be used for other situations though, for sure. :] It would be a more versatile texture, for starters, cause you'd always have some more leaves to play with if you wanted. Perhaps if you made a 4 way tiling ivy texture with the vines included, you could cover walls, but have a more sparse one for a different area, or vertex blend it from one of the more dense masks to a sparse mask.
  • Shogun3d
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    Shogun3d polycounter lvl 12
    Uly wrote: »
    thanks guys
    Kaburan: Not in this case, no. What you see in Step 3 is pretty much the final diffuse texture. (on the far right.) Reason being this ivy needed vines to connect the leaves, cause it was a relatively sparse configuration. If the whole thing was covered in Ivy, you would see many leaves over where your vines would be in the mask.

    The diffuse is a very dense collection of ivy, however. What I do with my alternative masks is mask out excess leaves and ivy, for a more sparse configuration when I need it. Or having the leaves bunch up on one particular side if it's growing in at a corner.

    What you're suggesting could be used for other situations though, for sure. :] Perhaps if you made a 4 way tiling ivy texture with the vines included, you could cover walls, but have a more sparse one for a different area, or vertex blend it from one of the more dense masks to a sparse mask.

    Very cool, thanks for the clarification! Great tut!
  • aphexx
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    aphexx polycounter lvl 12
    pretty much everything said in here. you guys made awesome tutorials!
    here's my (not so fancy) approach.
    basically was rendering highpoly ivy chunks to planes, with ivygenerator. then having 4-5 different imageparts and placing them on geometry, all with normalmap and AO, like the others also did in their tutorials. (AO is missing in this shot though, since it was for a lecture and we were in a rush)
    then i also put a single leaf on the texture sheet and placed single leaves, for that you also get some detail volume when watching the ivy from the sides.
    also the single leaves will drop some shadow onto underlying ivy-planes.
    some parts should be double sided, when the ingame camera can look underneath from easy angles.
    btw. our programmers told me, that you should roughly cut away transparent parts of your planes, since any pixel region on the plane have to be tested on alpha information. and when theres no mesh, nothing have to be tested, so its cheaper, even when 1-bit alpha is used.

    ivy_blog.jpg
    ivy_wire_blog.jpg

    ivy_blog.jpg
  • POFFINGTON
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    POFFINGTON polycounter lvl 11
    This was a amazing plethora of tutorials guys, thanks for all of the information!
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