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Tutorials LightWave 3D Big Eyes, Small Specs Qua Jan 26, 2011 4:11 am
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| Making Anime Eye Specularity Hits in Lightwave 8 by Nick Floyd |
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| Download source files here. |
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 As the DAVE School class of April 2005 began the anime short, Spoonman, we discussed several elements we would like to see in the finished film. One of those elements was to have two hard edged anime style specularity hits on the eyes of our characters and have them flicker in classic anime fashion. We also needed them to be able to move independently from the eyeball and each other so that they could be positioned for each individual camera during shooting. The early plan for this set up was simply a pair of image maps on the eyeball of the character controlled by reference nulls. In testing, this idea fell through as the further the rig was taken from the origin the harder it was to find the image maps. We tried to simply repeat the image map so one instance was always visible, but with this set up, scaling the images to get them to flicker caused the repeats to shrink in toward the original image and move across the eye. This problem would have been impossible to fix without a great deal of math. Save the math for the programmers. We’re animators.  I spent a day of production time working on this issue and eventually scrapped the image map/reference null idea for an easier rig based on the common eye bone set up. Below is the step by step method I used to create this rig. Step One. Create one eye down the same axis your character is facing as a perfect globe using the Ball tool. Making sure that there is an even number of both sides and segments and there is enough geometry to give the globe the illusion of being perfectly round with smoothing or SubD. This is the eyeball that must line up with your eye sockets and eye lids as the other geometry we are going to add will be mostly transparent. Normally, I wouldn’t recommend leaving a character’s iris round (its usually concave), but because it is cell shaded anime and because we will be copying it in the next step, we will leave them round. For now give the eyeball a white, 100% Luminosity surface called Eye_Whites.  Step Two. Select the eyeball geometry and change the Action Center Mode to Selection (Shift+F8). Copy and paste the geometry and Size it up slightly so that the second ball is slightly larger and directly over the first. Copy and paste this new ball and Size it the same amount. Now you have three balls whose centers are all exactly the same and each is slightly larger than the one directly below it. These two new balls will be the spec layers (one for the large and one for the small hits). Change the Action Center back to Mouse or whatever you prefer to work in.  Step Three. Texture the interior ball as an eyeball (I used a UV for the iris), and then Mirror all three balls to create the other eye. Surface each spec layer separately with right and left and large and small distinctions (white, 100% Luminosity). The balls that lie in the center are the large specs and outer one is the small spec. Now, create the two image maps in whatever image manipulation program you prefer. They should be a simple black dot for the small spec and a larger oval for the large spec. Both should be black and centered on a square white background.  Step Four. Now put the new images on the appropriate surfaces as Planner maps down the same axis the character faces. They should be in the Color Channel and set their Width and Height Tiles to Edge. Automatic Size them. This will make it possible to see the size of the specs in Modeler and Layout’s Open GL. Adjust the size until it looks right but be sure the X, Y, and Z are all exactly the same. You will need to hide the small spec geometry to be able to see the large specs.  Step Five. Once the specs appear to be the appropriate size, copy those texture layers into the Transparency channel and uncheck them in the Color channel. Now the character’s eyes will appear as white globes again in Modeler and Open GL, but a render will show a white oval over the iris of the eye.  Step Six. Weight map (200%) each layer of each eye with Right and Left designations as well as large and small spec and eye. Left_Eye, Left_Large_Spec, Left_Small_Spec, Right_Eye, Right_Large_Spec, and Right_Small_Spec.  Step Seven. Create two Skelegons in the left eye (an eye bone and a base bone) and make sure the joint of the two Skelegons are perfectly centered within the three spheres. Use the coordinates of the points on the spheres directly above and to the sides to center and straighten the Skelegons. It is very important that this is done right. The bone joint must be perfectly centered within the eye.  Step Eight. Send the object to Layout and Convert Skelegons to bones. Rename the base bone as Left_BASE and the other as Left_Eye. Now select the Left_Eye bone and make two clones of it. Rename one of the clones Left_Large_Spec and the other Left_Small_Spec.  Step Nine. Next, open up the Bone Properties panel and set the weight maps for each bone to the correct map created in Step Six. Set the Strength of Left_BASE to 0%.  Step Ten. Now, select Left_BASE and Mirror Hierarchy remembering to Replace String from Left to Right. The weight maps will convert automatically.  Step Eleven. Create a null object and center it directly between the character’s eyes. Clone it and move the clone so that the left eye bones are pointing directly at it. Be as precise as possible.  Step Twelve. Now Mirror the new null so that there is also one in front of the right eye. Parent both nulls to the central null. Be sure Parent in Place is on in the General Options panel before doing this.  Step Thirteen. Select the parent null and Clone Hierarchy twice, moving the new parent nulls closer to the character and offsetting them from each other. The furthest set of nulls are the eye targets while the closer sets are the Large and Small Spec targets respectively. They can be renamed as such.  Step Fourteen. The two eye targets can be hidden of course, but I recommend giving all the others an identifiable color, shape and label with Item Shape.  Step Fifteen. Now go into the Motion Options for each bone and assign the targets to the corresponding null object. The three master nulls in the center are not to be targeted and are only used to control their child nulls. The two BASE bones should not be assigned targets.  Step Sixteen. Next, add Follower to the large spec bones and set them to follow their target null Bank to Bank at a -1 Multiplier. The other channels should be set to “none.” The Large specs are usually at 45 degrees on the eye but this set up allows you to change the side of the character the spec lies on and rotate the spec to the best angle. Rotate the Large Spec nulls (not the Large_Spec_Master) 45 degrees on the Bank once Follower has been set.  Step Seventeen. Now move the master nulls of both specs up and toward the side of the character you are shooting from to get the position desired. Test renders will need to be done as the biggest problem with this rig is that they cannot be seen in Open GL. The individual spec nulls can be moved independently so that they can be seen on both eyes in a given shot as long as they are not in a noticeably different position. Remember that they are suppose to be reflections of light and should appear to be identical on each eye.  Step Eighteen. Now that you have the specs in place, go back to the surface settings and put an envelope on all three size channels (X, Y, and Z) of the spec layers. Each shot may require a different setting, but a change of about 5 or 6 mm over the course of three frames seems to do well. Don’t forget to set the post and pre behavior to Oscillate. Make sure that all spec layers have the same amount of change over the same time period so they are fluctuating the same amount at the same speed. These envelopes will save to the object and the specs will flicker in any scene it is placed.  That is it. Be sure to save your scene and the object. On Spoonman, we only used this rig on close up shots as distance seemed to make the extra bones and nulls more work than they would be worth. In all other shots we used a version of the character that had stationary spec hits.  You may want to parent the master nulls of this rig to the character’s head bone, the character’s master or mover null, or the character itself. Note, depending on the amount of movement the character makes in the shot, and where the master nulls are parented, the master spec nulls may also need to be animated somewhat to keep the illusion of them being reflections of light from a stationary source. Good luck Be Sure to Download the source files for this tutorial here. |
