Ant Tutorial – Part 2
This tutorial continues on building the ant character, including UV mapping and texturing, rigging, and animation. These are most very repetitive processes, so I don’t go into as much depth as for the modeling part. Most of these I’ll show you how to do one component and you can repeat the process for the rest of the model.
Here’s the final animation:
UV Mapping & Texturing
You can start with your completed model from the first part, or open antFinalModel.ma to use my finished version.
UV mapping maps UxV coordinates on a 2D image to 3D points. You don’t need to do this for solid colored objects. UV seams are best in places that are less visible, since they can sometimes cause black spots and show misalignment in mapped images
You can do automatic mapping (Create UVs -> Automatic Mapping), but this creates a lot of fragments and is pretty much useless
- In the Perspective viewport, go to Panels -> Saved Layouts -> persp/UV editor
- Go to Display -> Polygons -> Texture Border Edges to see the bolded UV shell borders.
- Select the faces on the tail
- Create UVs -> Spherical mapping
- Drag the manipulators on the sphere to create as regular mapping as possible. Click on the T on the projection to switch to the manipulator tool, click it again to go back
- Drag the the UV shell off the grid to make it easier to see
- Go to Image -> Shade UVs. You want to get all the UVs blue, as these are normalized and have no overlapping UVs. The red and purple show backwards and overlapping UVs, which will cause problems while texturing
- You can stitch together UVs to fix overlapping and backwards UVs. Right click -> UVs, then you can drag UVs around in the UV editor. The easiest way to stitch UVs together is to select the Shortest Edge Path tool, then click on UV points along the edge you want to stitch. Then go to Polygons -> Sew UV Edges
- Repeat selecting parts of the ant, then creating the UVs by create projections with the closest shape to the part. For example, use cylindrical projections for legs, spherical for the body, etc.
- An easy way to do the legs it to create a cylindrical projection, then move and rotate the project to so that the UV image looks like a flattened version of the leg (it might be purple, that’s alright).
- Then use the Select Shortest Edge Path tool to find a seam along the bottom of the leg, then go to Polygons -> Cut UV Edges.
- Go to Polygon -> Unfold to flatten the UVs, and it should be blue (indicating that it is non-overlapping and facing the right direction)
- You can also delete the faces on one half of the ant like for the modeling process, and UV map the remaining half. Mirror the geometry like for modeling the ant, and the UV mappings will also be mirrored. Then stitch the two halves together by selecting shared edge border paths and sewing them together.
- Select UV shells and use Polygon -> Unfold and Polygon -> Relax to make the UVs look more regular. You can also adjust them by UV Smoothing or Smudging.
Unless for some reason you really love the tedious process UV mapping, just learn how to do the mappings and there’s a finished, mapped ant (antFinalUV.ma).
Assigning materials controls how light interacts with your model. There are tons of variables you can control, we’ll just go over some of the basics.
- With the model selected, right click -> Add New Material.
- The dialog contains a long list of materials. You only really need three: Lambert, Phong, and Blinn. Lambert is the default, and best for non-reflective surfaces. Blinn is best for shiny surfaces, and Phong is pretty much like Lambert but with more specular highlights.
- In the Material attribute editor, you can control the material’s color, transparency, luminescence, and various other aspects.
- Play with various values and attributes to see what they do. If you don’t like it, you can always undo or assign a new material. I used Phong with settings so that it would be shiny, but not reflective.
- The most basic mapping we need is color mapping. You can assign a solid color by just clicking the big box next to Color.
- To paint the colors directly onto the ant, click on the checkered box next to Color in the material’s attribute editor. Click File in the dialog that pops up.
- Then go to Texturing -> 3D Paint Tool -> Options in the Rendering menu set. Now just paint directly on the model! Warning: this is fairly calculation intensive and can crash Maya on slower computers.
I just painted this ant really quickly, you can get as detailed as you like. You can also touch up the image in Photoshop by clicking on the box/arrow next to Color to see the file node, and find where the source file is (Image Name). This is tricky because you also need to get the UV mappings to tell where on the model you’re painting, as well as avoid mismatching seams.
Character setup is the process of creating the joints and skeleton for a character and binding it to the skin (the model), and controlling how the model deforms when it moves.
- Switch to the Animation menu set.
- To start creating the joints, go to Skeleton -> Joint Tool. Click where the joints should be, starting at the root of the chain.
- It’s best to create the joints in an orthogonal view (NOT perspective view), then move the joints into place. – You can move all following joints in a chain, or move a single joint by hitting the insert key when in the move tool.
- To connect the joints into a skeleton, go to Window -> Hypergraph: Hierarchy. Select a joint chain for a leg, and middle mouse button drag it onto the parenting joint.
- You can just do the legs/antennae on one side, then mirror them by going Skeleton -> Mirror Joint
- Once the skeleton is set up, select both the skeleton and the ant model. Go to Skin -> Bind Skin -> Smooth Bind -> Options
- Set Influences to 1, since ants are rigid enough to rely on one joint and don’t need the skin to deform/stretch much.
- The ant model is now bound to the skeleton, try moving some joints around and seeing how it moves.
- To set up inverse kinematics for the legs, go to Skeleton -> IK Handle Tool -> Options. Set Current solver to ikRPsolver
- Now click on the root joint, then on the tip joint. Now if you move the tip joint, the rest of the leg will bend accordingly.
You can create various other objects in the scene if you like, like a ground for it to walk on, grass, a sky, etc.
- Create lights by going to Create -> Lights > (light). Then move them around in the scene, rotate, and change attributes to manipulate how the light looks and where it points
- To see basically what the lighting will look like, click the yellow ball in the viewport. This can slow Maya down sometimes.
Basic light types:
- spotlight (desk lamps, 3 pt lighting)
- directional (parallel, sunlight)
- point light (light bulb)
Use the timeline on the bottom to set keyframes. You will need to keyframe each object you want to move, for example keyframing the IK handle to bend a leg.
Set the current frame to 1
Press the s key to set a keyframe
Move ahead a few frames
Move the object and press s again
Now you can scrub through the timeline and see it move!
There’s a short clip of a walk I animated at the top of this page (ants move their front and back legs on one side, and the middle leg on the other side, for each step).
Rendering the image means that the 3D space is projected into a 2D image. Usually this is done with ray tracing, which emits rays from a point (the camera) and calculates the color values for a pixel as it bounces around the scene until it reaches a light source.
- Click on the little clapboard icon with two wheels to open the Render Settings Dialog
- In Render Using, select mental ray
- In the Common tab, change the settings in File Out to set the name, file format, and naming format for the render. If you are rendering a still, you can ignore the next step and go on.
- If you are rendering an animation, choose multiframe or an option with ‘#’ in the Frame/Animation ext: field. In Frame Range, set the start and end frames.
- Make sure the image size and camera settings are correct.
- In the Quality tab, set Quality Presets to Draft if you are just testing a render, set it to Production for the final product. Production will take much longer to render, so only do this toward the end.
- Now you are ready to render! For a single frame or still, click the clapboard icon.
- For an animation, go to Render -> Batch Render. This will render in the background, and the status line at the bottom will tell you when it is done.