This tutorial was orginally a forum post to answer a question here at the DoE. It has been reposted here as a tutorial so that others may benefit from it who may have missed the forum thread that spawned its creation.
This is a fairly basic tutorial however some WorldCraft experience is required for it to make sense to you. You should be familiar with the basic operation of WorldCraft (selection methods, camera movement, etc.), have a grasp on how to use the texture application features, and have at least played with the vertex manipulation tool once or twice to get the feel for how it works.
In this tutorial I'll show you how to create an irregular depression in the ground and fill it with water to create a pond. Its the perfect thing to break up a large open area or fill that odd boring bit of your latest map. So lets fire up WorldCraft and get started...
start with a basic oversized chunky hole where your pond will be.
create a new block then using vertex manipulation merge one of its sides to create a wedge (you can also use the clip tool here but better get used to the vertex manip tool cause it is used heavily later on)
Use the wedge shape to create a rough outline of your pond. Now if all you want is a very basic pond skip ahead to step 6 now. Its easiest to shift-drag to duplicate the original wedge then use vertex manip in the top view window to arange the wedges on the grid. Note when moving the wedge corners with vertex manipulation be sure to get BOTH handles selected or you could end up with invalid solids in your map.
This is where it gets interesting. Create two more wedges as in step 2 then, using vertext manipulation form these two wedge shapes (figure 4). These shapes are probably the most useful ones you'll ever use, learn them well. The firts one, with the vertical rectangular side (on left)has 5 points, think pyrimid layed on its side. The other shape (on the right) has only 4 points such that all 4 sides are triagles. The second shape is very important, you can never create an invalid solid with this shape. Remember that.
Start arranging copies of these brushes such that the narrow ends all match together and the tall ends all match together. Vertex manipulation is heavily used during this step to align all the triangles. Look at figure 5 and note how i've alternated(usually) the 5 point brushes and the 4 point brushes to form the irregular slopes into the ponds bottom. In figure 5 the cyan(light blue) is the original square hole, the dark blue are the 6 point wedges, the green shows the 5 point brushes, the orange shows the 4 point brushes, and lastly the red shows the bottom of the pond which is a standard brush.
Create a standard brush to fit into the original hole from step 1.
Open your texture editor and select a texture that starts with "!", these will all be water in game if the texture is on all sides of the brush. Teture the brush with your selected water texture. (if you want to you can turn this brush into a func_water if you want waves and transparency) now move the new water brush into the pond, place it so the water touches the bottom of the pond. now in the side view in WC select the water and adjust its height to where you want your water level to be in the pond. having the water lower than the surrounding ground will cause the irregular edges to appear. Now you have an irregular pond!
You can use the techniques I showed above for almost ANY irregular shape. I've used this technique hundreds of times in my own maps with great results time after time. Just to give you some examples of how it can be used in your maps:
Best of luck to you in your next mapping project.