   render a forest
  what is the best way to render a forest.the character is going to be walking through grasslands and eventually will see a forest.  he/she will walk towards the forest and eventually be walking through the forest.so what is the best way to render the forest ?billboards look like complete crapand how expensive, fps wise, is it to draw a good many trees to simulate a forest ?and does anyone have any really low-poly tree models ?   "A soldier is a part of the 1% of the population that keeps the other 99% free"  - Lt. Colonel Todd, 1/38th Infantry, Ft. Benning, GA 
  Render the trees closest to the player as full 3d models.  Render trees a medium distance away as just a trunk and leaves (no branches).  Render those farthest away as billboards.  Far enough away, the player won''t be able to tell if the billboards are the full 3dmodels or not.  For improved billboard images, render the tree to a texture. ;  Well, the real-time One Million Trees demo from IDV is a rather good indicator of how many trees you can draw per frame. It uses a range of methods. Trees in the distance are simple billboards. As you state, this isn't too good up close, so at a certain threshold, tree models are used. The trees closest to the camera have the most detail, with bumpmaps and high-res textures. Another major area you'll need to investigate is frustum culling, whereby trees which cannot be seen are not drawn. If you stood in the exact centre of a circular forest, with a 90 degree view frustum, you'd only be rendering 25% of the total number of trees in the forest per frame. Only 10% of these might actually be close enough to the camera to warrant a model, leaving the other 15% to be billboards. It's just a question of employing little tricks here and there to give the illusion of a massive forest... EDIT: Hmmm. I should read other posts before posting, shouldn't I?Windows 95 - 32 bit extensions and a graphical shell for a 16 bit patch to an 8 bit operating system originally coded for a 4 bit microprocessor, written by a 2 bit company that can't stand 1 bit of competition.   [edited by - iNsAn1tY on February 14, 2004 8:10:28 PM]