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Modeling the Tiger Tank. Tutorial By Kevin Wafer
	Welcome to Kevin Wafer's Tiger Tank tutorial. This tutorial is compiled from actual savepoints that I created from the start to the finish of this project. This tank is a low polygon game resolution mesh and is highly optimised. Please click on the thumbnails to get a larger version image. You can email me at kevinwafer@kevinwafer.com. Thanks for visiting!
	Planning is vital if you want to build geometry quickly, cleanly and accurately. The first thing to do is to get a blueprint of your tank form a search engine, or scan it from a book. Make sure that all the views are on one bitmap. The next tasks is to set up your image planes. If you`re using Maya you can use the built in Maya camera image planes which are actually quite good! Or you can make your own image plane geometries. For objects and vehicles, I prefer to use my own image plane geometries, as I can move them around, change their transparency, hide and unhide them. Be very careful not to distort your image planes. Map the whole blueprint bitmap to a quad with the same aspect ratio as the bitmap, and then cut the quad up into pieces. This approach is easier than trying to UV lots of seperate planes.
	First I start modeling the turret, you don't have to start with the turret. The reason I start with the turret is because this is the hardest component to get perfect. I don't want to leave it until later or get distracted by modeling other geometry because it`s very obvious there is something wrong with your model if the turret isn't perfect. I laid down splines in a top view, and then I created a cylinder and moved the verticies of the cylinder to the spline curvature. I always make sure that the curvature is perfect before I move on.
	The hull is the key piece. This will be the largest component that all the other components will be built around. This has to be correct first time. The hull is relatively easy to model as it is angular, there aren't any awkward curves to worry about. I start with a cube, with 3,3,3 divisions. I begin blocking out the hull by moving the cube into place and scale it to the approximate correct size. I then face extrude the upper side faces to create an extra 2 divisions in the top half of the cube. This new extruded geometry will become the hull struture which sits above the tracks. Once I have done this, I manually tweak the verticies to algin them with the image plane blueprint.
	Now to the business end of the tank, the piece that you`d rather not have pointing at you...the gun. The gun is basically one big long cylinder with lots of divisions. I create a cylinder with 10 sides (in Maya, 10 'subdivision axis') and 12 height divisions. I then scale and translate the verticies to get the desired shapes, closely following the gun in the image plane.
	I add the wheels that the tracks will sit on. I also add the main commander hatch. These are all made from cylinders which I have edited by pulling, pushing and scaling verticies around to the desired form. I have been very careful to keep these with the bare minimum divisions to convey roundness but not appear too obviously angular.
	I add all the other hatches which are a little bit more complicated. The gunner hatch is basically a beveled cube with the top face extruded downwards/inwards so that the faces around this face become raised. I added more divisons to this hatch and then modified the vertex positions to match the form to the real tank. The lower hatches are a combination of a cube and a cylinder with further vertex level edits.
	Next up is the machine gun, and the machine gun port. The machine gun itself is a prism -- a 3 sided stretched cube basically. The size of this item doesn't require any more geometry than this. The machine gun port is a capsule, or cylinder with the end ronded. I then move the end verticies into a square shape to make the opening, and then extruded this inwards. You can see that I also made a start on the drivers port. Just adding a cube for now which I have stretched to the correct form. The rest of the drivers port is made of cubes.
	It`s time to start on the intricate backend, tanks aren't just steel boxes afterall! I begin work on the exhaust pipes and exhaust covers. These are all modified cylinders just like the gun. The reason the exhaust pipes come out here is so that the tank can drive through small rivers or streams.
	I add the oxygen cylinders and breathing pipes which all allow the tank to wade through rivers (correct me if I`m wrong about their purpose). The pipes are built from a cube which I have extruded one of the faces on multiple times. We can't waste polygons on a lovely round twisty tube considering where this detail is on the tank, and besides, once we have a texture and a normal map on it, it`ll look round.
	Tracks.. Now here's the thing. Modeling a set of tracks accurately is going to take many thousands of polygons. So we have to think clever, we need to employ clever textures. A colour map of course, as always, but we must also use a normal map, and a specular map to add the required illusion of detail. The actual track geometry was created from two splines which were then lofted, the resulting geometry was cleaned up as there were too many divisions. The lofted geometry was then extruded to give the main width of the track.
	Final tweaks and details added. Smoke throwers and a large bolt were added to the turret. Front drive wheels now have a `cog` plane added so that the drive wheel is not just a cyclinder. The back drive wheel's form is now correct. A plane for the tow wires was added to the top of the hull. Completed wheels and tracks copied over to the other side.
	Final optimisations and clean up. Removed excess divisions and fixed any crashing/burried geometry. Final triangle count is 4467 triangles, final polygon count is 2684. The finished tank can be seen here : www.kevinwafer.com/art.html