This is a tutorial explaining how to unwrap handguns that were modelled with a game-poly range eg. 1000ish. The skills taught can be applied to other areas of unwrapping but obviously they are most relevant to this specific purpose. Please note that I am a n00b web-designer as is obvious by my website so judge the usefull-ness of this tutorial on what it teaches not how flashy it is.
Also ... the tutorial is very image heavy so please bear with it while it loads.
If you wish to comment on it do so at my Deviant Art Site
And if you are on a crap connection I sympathise with you so please ... download the tutorial in this zip file (models not included)
Enough talk ... on with the tutorial:
Checkered faces are important while making an unwrap of a weapon because they allow you to see how evenly distributed the resolution is for your skinner. Obviously each Checker represents a certain number of pixels but what is more important is each checker is a different size compared to one on another part of the mesh.
This is a cockpit model with a checker map applied. Each checker represents roughly 25x25 pixels if the Cockpit is given a 1024x1024 map.
The Checkers do not need to be perfectly evenly distributed. However it is best if they are as close as possible for game models; unless there is a dire need for a lot of detail in 1 particular area. One example of a need like that is if you were doing Iron sights.
You do not have to use this technique. It is more of a guide tool and eventually you will stop using it once you've learnt to unwrap well enough.
To get a Checkered map set up go to your material editor. Go to the maps rollout and expand it, find the Diffuse color spot and where it says NONE next to this click so that you can apply your map type. A Material Map Browser dialog box will now appear, scroll down the list to find 'checker'. Then once you have chosen a checker map you need to increase the tiling so that you can see more copies of the checkers. Change the 1.0 values to something like 40 (divide your texture resolution by 40 to figure out what each checker represents).
Now to get this new material applied click on the drop down box where it says "Map #" and choose the top option on that list (should have the word default in the name).
Check the 2-sided box if your mesh needs this. Click on the checkered box to make the map show when applied. Then click on the button that has a blue sphere, white square and a curved arrow pictured. This button applies the material to your mesh.
Now we are ready to begin
This is simple. Attach all separated mesh parts. Basically convert to editable mesh then click the attach list button under the modifier panel and select all.
In edit mesh you can select the parts you would like to unwrap. So if you want to isolate sections of your unwrap select them using the face or object types of edit mesh.
To begin with for the SOCOM we are going to unwrap 1 side and only 1 side. This is so we can give the skinners an accurately and evenly unwrapped shape. Select all faces on the left side of the gun as so:
Now add a UVW unwrap modifier from the modify panel. Once this is done click the edit button on the panel. A new window will open ... this is where most of the work is done for unwrapping. Within this box you will have the faces you selected in edit mesh, however they may be in an odd shape.
To correct this you need to use the normal mapping tool. This tool allows you to make captures of what your selected faces look like from certain angles. We obviously want to normal map the side view however 3D studios MAX doesn't always make sense as you all should know by now. So click mapping ... then normal mapping ... then top/bottom mapping. However before you click ok uncheck the 'rotate clusters' check box as this can be quite irritating sometimes.
Now, as you will want to correct the positioning and rotation of your model you can click the rotate +90 or -90 buttons at the bottom of the unwrapping window. This should make your unwrap look something like this so far:
Right click on the modifier stack (where UVW unwrap is on the modify panel) and select collapse all. This will return your mesh to a partially unwrapped editable mesh.
Now select the top faces including the tops of the sights and repeat the previous process with one exception. Instead of normal mapping 'top/bottom' use 'front/back'.
This shows what it should look like in the UVW unwrap edit window if you add the UVW unwrap modifier with no faces selected.
Now comes the complicated task of attaching these two objects. However first I must tell you about one of the weaknesses of normal mapping. As it takes a snapshot from a particular side of the model angled faces get shrunk a little. To compensate for this you have to rescale them.
Selecting and moving objects within this window is just like a 2D version of editing vertices so treat it as such. Grab the vertices I have selected and press the scale button (within the window) until a small drop down menu comes down and select the vertical scale only button. Then scale and move these vertices until they appear something like what I've done in this picture:
As you've probably noticed the top faces don't quite match the scale of the side faces. Correct this using uniform scale so we don't get stretched textures. The vertices and edges that get highlighted in blue when you select the top faces are the ones that the top lines up with. Try to match them as closely as possible but don't put the top directly next to your side face just yet.
(snap button is the button highlighted in yellow in the picture below)
Now ... we get to use grid snap. If you have the mouse over the vertice you want your selection to snap to it will snap that vertice to the lines on the grid. Snap the side faces to a corner on this grid. Then move the top faces to that corner as well.
You will probably notice that your scale wasn't perfect. To correct this you can snap the vertices that don't line up with their counter-parts and snap their counter-parts into place.
This one is easy to explain repeat the above process for the other side of the gun. The picture will explain this if you don't get what I'm saying.
With nothing selected go to your UVW unwrap edit window. Then click the plus symbol next to UVW unwrap on the modifier stack and click on the 'select face' option which appears. Use this tool to select the faces along the front and back of the handle as such:
These faces will now be selected in the unwrapping window. Normal map them using the left/right type of mapping and scale \ rotate them to correspond with the front and back edges of your handle. If rotating them is annoying then use 'flip vertical' and 'flip horizontal' under the tools menu.
Now use the technique you learnt earlier to attach or move vertices to snap locations. This will help you line up the front and back of the handle with the corresponding edges. The first picture picture shows me as I began to do this. The second picture shows what it should look like once completed.
You may also wish to attach the following side faces to your unwrap in the following fashion. Use the techniques you have already learnt and try and experiment a little with the move, scale and flipping tools as you complete this task.
Now you must unwrap the cylinders that make up the silencer. This process does not use normal mapping as cylinders do not appear evenly stretched if mapped from the sides. To start, select all the round edges of the silencer (but not cap-faces such as right at the end). Then detach these faces (to a separate mesh of their own). Select this new mesh and we can continue.
Now we add the UVW Mapping modifier. This is found just below the UVW unwrapping modifier we have been using of late. Once you've selected this modifier choose the Cylindrical option to make the modifier use a cylinder shaped gizmo. Then choose to align the gizmo on the Y axis and ... finally 'fit' it to your object.
Once this is done 3D studios will refer to the gizmo to understand how to unwrap the faces in question. Instead of being pretty much random, it will make a near perfect unwrap of the faces according to how they face the gizmo. Use the UVW uwnrapping modifier to view this.
When unwrapping a cylinder it is important to realise that most cylinders can be mirrored in half. Selecting the faces that make up the silencer as I do below, press the D button to detach the faces then press tools and mirror horizontal so that the faces you 'snap' together are faces that connect on the outside of the mesh.
The second picture shows what this will look like after this is complete (and the silencer has been re-attached to the main mesh).
Now we get all the other parts of the mesh into a visible normal mapped state. To make things neat and easily workable right click on the UVW unwrapping modifier on the modify panel and click collapse all. Then, while in edit mesh make sure you have no faces selected and are currently not in any selection sub modes (such as element, vertice or face selection).
Now add a new UVVW unwrapping modifier and select the small dot (where the 2 bold blue lines meet). This blue dot is where the rest of the mesh has been hiding all along. When working with other meshes the unwrap may not be as neatly hidden. In fact it could be all over the place; making work quite difficult. However this is fairly easy to deal with so I won't bother teaching you how to get around this.
Once you have this dot selected click mapping, normal mapping, box mapping. This will take a picture from each side (left, right, top, bottom, front, back) in order to organise what is left. At first what it shows may look confusing. However you can clearly see the magazine, trigger and trigger guard showing through the mess.
This stage is where you begin to teach yourself. Use the skilled I have taught you previously to sort through the mess that is left. A few tips for how to help yourself out here:
Now is where you start thinking about packing your unwrap. By now you should have all those parts you normal mapped earlier neatly organised. On my model I had the following components to unwrap:
In the following picture you can see how I've scaled the main attached parts to fit nicely within the bold blue lines, which of course represent your non-tiled skin that is no doubt coming soon. As you can see the main parts of the gun often have problems fitting in with maximum resolution. However you can solve this problem by being creative. Try and pack things in as much as you physically can (without having too smaller gaps between faces)
Once you've completed packing your job as an unwrapper is complete. Consult coders and the original modeller to figure out how certain parts will be animated (and therefore need to be detached). Apart from that, as long as your unwrap looks similar to this, then I guess my use to you is up until you want to learn how to unwrap planes and I want to write another tutorial.