Part Two: Good Modeling Techniques for Low-polygon CountsOf course, as I alluded to above with the boolean explanation, the best way to reduce polygons is to initially work with as few as possible. Prevention from the start is always easier than doing a cleanup job afterwards. The main techniques for mesh manipulation include extruding polygons, knifing polygons, deleting polygons, and bridging points to create new polygons. I'll be using the Ocean Patrol Fighter as an example for each of these methods in this part.Section 2-A: Getting Started, ExtrudingThere are really only two ways to get a base mesh to work with. You can either use a primitive like a cube or you can use NURBS to build an object from splines. NURBS is an excellent tool for creating organic meshes that have lots of curves, but the simple cube primitive is sufficient for the work I'll be explaining here.Create a new scene and add a cube object. We're going to build the majority of the Ocean Patrol's hull from that simple cube. Skeptical? Good. I was too when I followed a lesson for sculpting my first human head out of a simple cube. This should be a little easier, though.
Before moving into the specific instructions, let's look at how we could make this from a cube. This is how I picture the process in my head. Usually before I start working on a mesh, I sketch some ideas on a pad of paper of *how* I'll try to make it. For this mesh, the initial cube would be the center piece of the fuselage. From that, we could add on to the sides and squash them down for the intakes. Then we could add on a piece to the front and squash it into the nose. Here's a sketch of how the process will go:Fuselage:Add intakes:Squash intakes:Add nose section:final state for main shape:Get it? Good. Now, let's get to work! Double click the Cube in the Object Manager and change the height to 100 m and width to 100 m. With the Cube still selected, click the Make Object Editable button or choose Make Editable from the Structure menu or press the 'C' key on your keyboard.Now that the cube is an actual mesh, we can select and manipulate its polygons and points. Choose the Use Polygon Tool and then the Live Selection tool. In the perspective view, select one of the narrow side faces. Rotate the view to the other side and then hold shift and select this side's polygon. As with word processors and other apps, the shift key adds to the current selection; so, both sides are currently selected.aside: You'll notice when you select polygons that a small yellow dot and line will point out from the center of each. This is pointing out so show the positive "normal" of polygon. Each polygon has two sides. When working with materials, you can set a texture tag to apply specifically to the front, back, or both sides of a polygon. The normals also determine which direction is positive or negative when doing things like extrude operations. The outward-pointing line indicates that you are seeing the front side of it here. In most cases, you want to have the front side of the polygons facing out. Whenever you make a primitive editable, all of the polygons' front sides will be facing out like this by default. When manually creating polygons, though, the normals may get twisted around. You can fix this by aligning or reversing it. I'll cover the details on this later.To add a new section from the selected polygons here, we use the extrude tool. Press the 'D' key or select extrude from the structure menu. By dragging left and right in the 3d view, you can quickly pull out the new polygons. Though, you will usually want a bit more precision. So, instead go directly to the Active Tool Manager. Change the offset setting to 110 and click apply. The preserve groups box and maximum angle don't really affect what we're doing now. Those are used for when you have a selection of several adjacent polygons. When the group is not preserved, it extrudes each polygon individually. When it is preserved, they pull out in a solid group together.Go to the Coordinates Manager now with the same two polygons selected. Also, switch your view (if you are using a single view) to the front view. With the Coordinates Manager, you can scale and move polygons just as you would whole objects. Change the Y scale (and others) to your likings. I used 40 m for the Y scale. After switching to the top view, I also reduced the Z scale to 150 m. To better match the angled shape of your original model, I also switched to the side view and moved the polygons 10 m in the Y direction and 10 m in the Z direction. We can fine tune any other details later. For now, you just want the basic shape.aside: I would recommend deleting the smoothing tag from the Cube object or reducing its angle limit to a small number like 5. Since we want these ship panels to appear flat, the shadowy gradient would just be a nuisance.Switch back to the Live Selection Tool and select the front center polygon that will be extruded for the nose. Extrude it by 130 m. Then use the Coordinates Manager to scale and move it into a better position as you did with the sides. Here are my settings:Of course, you'll note that the top part of the nose is tapered in your actual image here:We'll work on that bit of detail later with some individual point manipulation. This completes the first basic phase of this mesh's construction. Rejoice!(Edited by Bradster at 8:20 am on Dec. 3, 2002)