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'Cheap' Trees

Ever want to create a forest in Bryce and inserted about 40 trees from the Create menu? Start your render and then go on a three day vacation.

Why do the preset trees take so long to render? Are they an extremly complex dxf or 3ds? Did the bryce gods write in a special tree building code that would take forever but create a trunk and branch lovers nirvana? NOPE!

As with most things in Bryce, the preset trees are built up with primitives. Basically spheres and 2d planes. What makes them look so complex is the picture material that is applied to them. I got tired of waiting for trees to render and decided to look into this mythical creatures origins and this is what I found.

Can't see the trees for the forest!

Take a look at a forest some time. Do you see every trunk on every tree? I don't. I see dark undergrowth, the occasional trunk, and a canopy made of motlled shapes and colors. If you want to model a forest, model what you see. If you don't see these elements then why increase your render times by modelling them. You don't need a third party tree modeller (although they have a definate purpose), Meta gave you everything you need with Bryce. You just have to tear things apart a-little to get to them.

Start a new scene. Go to Create and select TREES. Find Tree4 which is circled below.

Import the tree and ungroup it. If you start pulling it apart you will find out why they take so long to render. I counted around 22 spheres and 5 2d planes! Starting to see why they take so long?

If you select one of the spheres and select 'M' for the materials editor, you will see 'IMAGE 44' has been used. I'm assuming this is a bryce internal image although I really haven't looked around for it to see if it can be loaded independantly. Since you have it in the material editor you can save it as a user preset and use it on other objects. Assuming you have some knowledge of the materials editor, you can assign a B channel to the ambience channel and use a bump map like 'greenstratus' to complicate the material and I like to darken the greens a-little. Our pupose here is not to explain the Mat. Editor so I'll just leave it at that.

Just make sure you have the tiling set to object top and blend transparacy. It's also a good idea to change the 2 specular colors to greens so you don't get white spots on your trees.

You can now apply this material to a 2d vertical plane (to the right of Leo on the create tab) Since it's on a plane, you can rotate the plane to vary the shape of the 'branch' and this also changes the appearance by the way the light strikes it. You can resize it really big and run it way back in the distance for a forest horizon or 'rubber stamp' yourself a forest by duplicating on after the other, rotating as you go. You can also apply this material to pyramids (evergreen like trees) spheres (much like the original) or any other shape. Just keep in mind the more complex shapes you have, the longer the render time. Build a background with these shapes and then put one or two full trees in the foreground for detail. The same process applies to the trunks in the originals. They are IMAGE 48.

Image 44 applied to a 2d plane and darkened a bit.

With a little discretion you should find that your whole forest takes less or at least no longer than it took to render one tree before. You can also try applying the image to the object front, parametric or any of the other options in the ME.

Here's a quick image I made with this technique. Render time was about 7 minutes and it has a nice oil painting touch to it I think.

'Up a Lazy River' c.98 Ed Baumgarten

Good luck and I hope this inspires you to rip apart the other elements in bryce. There's more there than meets the eye.

Keep Tweakin' and uh, don't hit your head on that branch!

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