An in-depth look at UV mapping an object in 3ds Max

[3dpoder]

.

[3dpoder]

Borrar.

[3dpoder]

In this tutorial ill be working with a space ship i modeled in max 5. It a Fairly complicated object mapping-Wise - It has Lots of curved surfaces mixed in with a lot of chamfered Edges and beveled segments, and theyre all going todo require a diferent method for mapping. For purposes of this tutorial im going todo be very precise when mapping this object, though in real life id probably settle for sloppier UVW coordinates in order todo save time.

If you would like todo follow along while working th rouge this tutorial, you can download the object here. This is the final mapped versión of the object, though you can use it starting at the beginning of the tutorial without any problems. I have todo warn you though, it a complicated Mesh, and you may be better of working with simple primitives or one of your own objects if you find yourself getting lost.


Before we begin, im going todo go over a few basic, and mention a few shortcuts. First, thre hotkeys youll find immensely useful are f2, f3, and f4. F2, when pressed, toggles Shade selected Faces mode - Essentially, when this mode is on, selected Faces Will appear in bright red. F3 toggles wireframe/shaded mode, and f4 toggles edged Faces mode. All are very useful throughout the modeling process, but especially when doing uvw-mapping.


Most of our UVW mapping Will be done in the Unwrap UVW modifier. If you havent done so already, select your object, and then add an Unwrap UVW modifier as shown on the right.


Last on our list of basic. Clicking on the Unwrap UVW modifier in the modifier stack Will go todo the select face sub-object level. This means you can click on your object in the viewport todo select the Faces you want todo work on, and theyll be highlighted in the edit UVW window. And. I hope you know this already, but you can Control-click todo add more Faces todo the selection set, and alt-click todo remove Faces.

[3dpoder]

With that out of the way, let begin. Click on the edit button todo bring up the edit UVWS window. What you se Will probably be a garbled mess, that fine, that just the default mapping coordinates for the Mesh.


Let simplify things a Little. If you didnt do so earlier, in the modifier stack, click on Unwrap UVW todo go todo select Face Mode. Drag a selection box around your entire object todo select all the Faces. Now, click on the planar map button in the Unwrap UVW ut. This should make your UVW mapping coordinates look a lot simpler (but still not ideal for texturing).


Now, if youll switch back todo the edit UVWS window, well briefly go over the major features of the interfaz. In the top-left corner of the dialog you have the basic modifier tools (move, rotate, scale, freeform, and mirror.) once again a handy Little tip, with the move and scale tools, holding [shift] before clicking Will allow you todo constraint the transformation along only one axis - Try it, im sure youll se where that can come in useful.


In the bottom-right corner of the interfaz youll find all the panning and zoming options, and below those are two buttons - Rotate +90 and rotate -90. Very straightforward, but very useful.


To the left of those is the selection modes box. This contains some of the most significant improvements over previous versións of the Unwrap UVW tool. By default, vertex sub-object mode is selected - But todo the right are buttons todo change todo Edge and face sub-object mode, respectively. In vertex mode, you modify mapping coordinates by moving around the corners of Polygons in UVW space. In Edge mode, you move the Edges between two vértices. In Face Mode, you got it, you move Faces around (which efectively moves the surrounding vértices).


Also note the + and - Buttons, which allow you todo expand and contract the current selection. Select element is quite nice to, but were not in a god position todo demonstrate its uses yet. Dont worry, well get todo it son enough.

Another great característica of the Unwrap UVW tool is that the selection in the edit UVW window is the same as the selection in the 3d viewports, so youll never have problems finding the right polygon. (this is one situation where turning on Shade selected Faces mode, f2, is very useful).

[3dpoder]

Now that you have a passing familiarity with the Unwrap UVW interfaz, let do some mapping. Before we begin, y always like todo apply a checkerboard texture todo my objects, so that it obvious when Polygons are mapped well. Go into the material editor, select an unused material, expand the maps ut, and click on the button todo the right of Diffuse color, labeled none. In the window that pops up, double-click bitmap, and go find a suitable checkerboard texture (dont have one? Here, use mine.) dont forget todo click the show map in viewport button, and apply the material todo the object. Your object should look something like the image todo the right.


Close the material editor and go back todo your edit UVWS window (you may have todo click edit again.) note that the object material now shows up as the background in the edit UVWS box - Isnt that handy? If you dont like it, you can always disable it by clicking the show map button at the top of the edit UVWS window. Also note the dark blue box in the grid. That designates the boundaries of your texture map. If you mapping coordinates go outside of it, theyll Wrap around todo the other side - So be careful. (you really dont ned todo worry about that until the end).


Let take a look at the first automatic UVW mapping method. Click on the mapping menú, then Flatten mapping. Make sure the thre checkboxes are checked, and hit ok. Youll se your object broken up into chunks, almost like pieces of a puzzle. If you printed this out and Cut out all the pieces, you could actually assemble them into a rouge versión of your object - Theyre not perfecto, but theyre pretty close.


This is a god place todo estop and demonstrate the select element característica. Check the box as sho, then click on any of the chunks in the edit UVWS window. Notice it selects the entire element, not just the face (or Edge or vertex) you clicked on. This is a great característica if you ned todo move whole chunks around.


But now that youve sen the default settings for Flatten mapping, let experiment a bit more. Go back todo mapping->Flatten mapping, and play with the parameters a bit - Specifically the face angle threshold spinner. A bigger number Will generally result in larger chunks, while a smaller number Will produce smaller, but more numerous chunks (there Will also be less stretching.) i used values of 75 and 25 for these examples. Depending on how youre going todo texture the object, both results have their merits. As for me, im not quite happy yet, so let play with some other mapping methods.


Go back todo the mapping menú, and click on normal mapping. In the dropdown menú at the top, select box mapping. All of the options are useful, but i use box mapping more often than the others. Hit ok todo se the results. The object has ben broken into six chunks, each mapped from a diferent direction. This has a major advantage over the box mapping option in the normal UVW map modifier - The six views of the object arent all placed on top of each other. But play with the options, try some of the other mapping methods (left/right mapping, perhaps?) and se if you find something you like. If not, well, were going todo have todo do something a Little more complicated.

[3dpoder]

To begin, im going todo re-apply Flatten mapping with the settings as shown at the right. This is as god a starting point as any, since i only have todo clean up the mapping coordinates i dont like. (most of the larger chunks should be usable).


One of the first problem áreas on my object is the Cockpit - It curvature is todo great for Flatten mapping todo place all of its Polygons in the same UVW mapping Clump. So what im going todo do is select all the Faces of the Cockpit in the perspective viewport, then in the Unwrap UVW modifier ut, click on planar map.


The result isnt quite ideal - The new mapping coordinates take up almost as much space as all the old ones combined, but it can be easily scaled back down todo match the other Polygons. I put the scaled coordinates of todo the side for now - Well rearrange everything later.


I found a couple situations where some Faces could be joined easily without overlapping, Even though planar mapping wouldnt work quite right. When you apply Flatten mapping, these usually end up as chunks of one or two Polygons just sitting on their own.


You can join these Polygons together pretty easily by going into Edge mode (make sure select element isnt checked), then select the common Edge on one of the two elements you want todo join. Note that the common Edge on the other element turns Purple.


Clicking on tools->Stitch selected Will connect the elements together (click ok on the Stitch tool dialog - The default settings are fine).


I stitched together a few more elements, but there are a few overlapping Polygons. A simple solution here is todo just weld the vértices together todo make one continuous piece. Itll cause a Little stretching, but if it on a small polygon, youll never notice. To do a target weld, click on tools->target weld, then click and drag a source vertex onto its destination. Much better.


You can se i was able todo connect together a nice run of Polygons using the Stitch tool and target welding.

[3dpoder]

Most of the tools weve loked at so far work well for very Low-polygon meshes, or meshes with relatively flat surfaces. In this section well look at using some of max traditional tools for mapping more complicated shapes. If youre going todo be mapping a character, for instance, youll find yourself using this technique more than any other, ive reached a point where ive got a lot of Polygons surrounding the main body of the ship that planar mapping just isnt ideal for. A cylindrical map would be best.

At this point i applied a Mesh Select modifier, and selected all of the Faces that fell roughly in a cylindrical shape around the body of the ship. (selecting the Faces in the Unwrap UVW modifier, unfortunately, doesnt work).

Note that at this point instead of adding a Mesh Select modifier, you could also collapse the modifier stack and select Faces at the polygon sub-object level.

When i finished selecting Faces i added a UVW mapping modifier. (diferent from the Unwrap UVW modifier.) i changed the mapping todo cilíndrica and hit fit. This fit the shape of the cylindrical mapping gizmo snugly around the Faces i had selected. In practice, you Will ned todo change the alignment of the gizmo if your Polygons arent lined up along the z axis.


At this point we have two choices. If there are other sections of the Mesh that ned special mapping (cylindrical, Spherical, etc), we could add another Mesh Select modifier, pick the Faces we want, and add another UVW mapping modifier on top of that. However, for our space ship Mesh there are only a couple simple bits todo clean up, so let get back todo our Unwrap UVW mode, before we can add the Unwrap UVW modifier, we ned todo make sure we have the correct Polygons selected. (right now only the Polygons we cylindrically mapped are selected.) so add another Mesh Select modifier and select all the Faces, then add the Unwrap UVW modifier on top of that, once again, the mapping coordinates arent quite ideal, so i scaled and moved them so that they dont overlap. It would also be nice todo break this large chunk up a bit. To do this, y selected the Faces that i wanted todo become a sepárate element, then clicked on tools->break (Control-b). Now i can move those Faces of todo the side without also stretching the adjacent Faces.

[3dpoder]

Using the above methods, ive managed todo Clump most of my Polygons together into nice UVW groupings, and get rid of most of the clusters of only one or two Polygons. In real life youd probably try todo group the Polygons together Even more, but weve gone far enough for this tutorial. Now all that left todo do is fit all the mapping clusters back into normal texture space (denoted by the blue square.) fortunately, max provides a tool todo do this todo.


Click on tools->pack UVS, and fill in the options as shown. Hit ok. You should get a nice, Even distribution of Polygons. Of course, you can do it manually by rotating and scaling chunks. This Will usually give you better results, but it much more time consuming. You can also put matched segments on top of each other todo conserve texture space.


And that it for the mapping. I recommend using a utility like texporter todo export the mapping coordinates todo an image, which you can use as a basis for your texture map.

Now, as i mentioned at the start, if i was mapping this object for real, y probably would have ben a bit sloppier with my mapping. I would have planar mapped larger groups of Polygons todo avoid having todo spend so much time stitching elements together, with the drawback that the object would have had more stretching. But at this point youve sen most of the new mapping tools, youve sen how todo do a quick job of mapping your object, and youve sen how todo do it all manually if you ned todo.