CAP 201a - Computer Animation I

Lesson 5 - Chapter 8, Character Poly Modeling (Part 2)

Objectives:

 

Chapter 8 continues the lesson on modeling, adding more features to the character. Objectives important to this lesson:

  1. Completing the body
  2. Accessories and uniform details
  3. Boots
  4. Hands
Concepts:

 

Project: the Soldier model (continued) 

The chapter begins with some remarks about the many uses of computer generated characters. Its list is short, actually. Computer models are used for anything you can think of.

Project Exercise 1: Reference planes 

The exercise starts by telling you to open either the file you saved last for this project or version 5 of the supplied Soldier files. You should continue with the model you have made, unless something has gone very wrong and you need to work from the supplied file. I hope that you can continue with your model, and that it has some features to distinguish it from the work of other people.

The text reminds you that you used the Symmetry method to mirror the Red Rocket. You will use a different method in this exercise.

  1. Start in the Front viewport as directed, and click the Select button. Select the model. Open the Hierarchy panel on the command console. Find and click the Affect Pivot Only button.

    Before you select the Move tool, look at the gizmo for the Pivot point. It looks like a structure of hollow arrows. Click the Move tool. The Pivot gizmo still appears on screen, but the Move gizmo is now the operative tool. I remark on this because some students become confused at this point by the overabundance of arrows on the screen in approximately the same place.

    Move
    the Pivot gizmo so that its vertical arrow straddles the inner vertical edge of the model.
  2. Turn off Affect Pivot only. The Pivot gizmo disappears.
    Carefully select all vertices on the open border of the model. You may find this easiest to do in two stages.
    First, do a marquee selection in the Front viewport of all vertices in the center of the screen.
    Next, look at another viewport set to Left view. Pan and zoom to make sure the right vertices are selected. This will also give you practice in manipulating your view of the model without deselecting your current selection. Ctrl-click any vertices that you need to add to the selection set, and Alt-click any you need to remove from the selection set. If you lost some, add them again.
    When the selection is right, go to the Graphite ribbon, Align tab, and click the button marked X. (Sometimes it is the right spot, Dr. Jones.)
    At this point, all selected vertices should have moved to a position where x=0. I would call this the y axis, not the x axis. Oh, well. I was more bothered at this point by the effort I spent getting the angle of the bridge structure right in the last exercise. It's kind of flat now.
  3. Begin the mirror function by clicking the Mirror button on the main toolbar. It looks like a capital M with a vertical line cutting it from top to bottom. Set Mirror Axis to X, and set Clone type to Instance, and click OK.
    You should recall that an instance is a copy that changes when its original changes, and the original changes when the instance changes.
  4. Don't switch to Edge subobject mode yet. If your model is like mine, the instance is currently selected, not the original. Change to object mode first, Then click away from the model. Next, click the side of the model we have been working on all along. (It is the model's left side, viewable from the Right viewport. Did you think I was kidding about knowing right from left? Not hardly.) Finally, go to Edge subobject mode.
    Select the edges that border the neck area of the model.
    Question 1: What is a two click method to select all of these edges?
    Shift-scale the edges only on the x and y axes. Your model should look something like the middle image on page 167. (The authors seem to be modeling in the perspective view. This is a bad habit that will bite you. Model in the Top viewport for this operation.)
    If you have the two v-shaped scallops shown in the center image, correct this by moving vertices. You may need to move the vertex at the bottom of each v as well as the one at the top. Move the one at the bottom if the instance model is overlapping the original model. (Mine was.) If the authors don't think of it in a few minutes, you will want to do this for all vertices, front and back, from the neck down to the leg. It may seem irrelevant soon, but it is not.
  5. If you went into Vertex mode, go back to Edge mode. Your set of neck edges should still be selected. If not, select them again. The text says to Shift-Move them toward the center of the model to make another set of polygons. This does not match the project photo on the next page, but let's do it anyway.
    Afterward, change to Vertex mode and correct the overlapping vertices that were just created.
  6. Return to Edge mode. The text says to shift-drag the edges on the z axis this time, into the model cavity.This should produce a ring of polygons like a collar for the uniform. Do that now.
    The next move is odd. The text says to shift-drag again to close a cap under the collar area. I tried to do this several ways, and the closest I can come is to drag only on the x (horizontal) axis. The image below is what I had, looking down, when I stopped dragging.



    The curved red line indicates where I needed to correct vertex placements. The problem I had doing it was that several of the vertices that had to be moved were hidden inside the instance model.
    So I changed back to object mode for safety, right clicked the original model, and chose Isolate Selection. This caused everything else in the scene to disappear. No more buried vertices. I found each vertex that needed to be moved, moved it, and then clicked the button in the middle of my screen to Exit Isolation Mode.

    Had I not gone into Isolation mode, I might not have realized how badly some vertices were occluded (hidden by another object). In this case, those vertices needed to be moved. In another case, they might need to be reconsidered altogether. Use Isolation mode as needed to see what an object in your scene looks like on its own.

    As part of the same step, the text tells us to go through the model and correct any "wonky geometry". This is the part I was afraid of. They are telling us to clean up anything that is wrong any way we can. If you did not follow my suggestion at the end of step 4, do it now. (Are you worried? You should save first whenever you are worried.)

    The authors really should have gone to another step here. They did not. They have given us a procedure, so I will go to substeps:
    1. First, go to object mode.
    2. Next, select the instance side of the model.
    3. Look on the Modify panel, under the modifier stack window, and find the Make Unique button.
    4. Click the Make Unique button. This removes the instance linkage between the two models. Remember that: they are two unlinked objects at this point. Changes to one will no longer be reflected in the other.
  7. Step 7 introduces a new tool, and a new situation.
    Select the original model, which the authors are calling the "right half". (Heavy sigh.) It is on the right side of the screen (until we move it, or orbit, or change the viewport), but it is the left side of the model itself.
    On the Graphite ribbon, Geometry (All) tab, click the Attach button. Then click the other half of the model.
    The new situation is that the two halves of the model are not actually connected. They are only logically connected. They will be treated like one object, even though they share no geometry.
    You can have several physically separate objects that are joined as parts of the same logical object in 3DS Max. This is your situation right now.
  8. Go to the Front viewport, if you are not there already. Go to vertex mode, and note that all vertices on both model halves light up. (One logical object, right?)
    Confirm that Ignore Backfacing is turned off.
    Question 2: Why is it a good idea to turn off this feature at this time?

    The next part may be easier if you imagine that this soldier is the child King Solomon threatened to cut in half. Enlarge the viewport and zoom so that you can see the edges of the entire gaping wound in the center of the body. You don't need to see the rest of it. Do that, then marquee select the vertices that run down the center of the model. Only select the ones that need to be welded from one side to the other to make one body. (Yes, select them from both halves of the body.)

    Go to the Graphite ribbon, Align tab, and click the X button.

    Again, the text says this aligns the vertices to the x axis.

    No, not really. That makes it sound like we moved the points to the line that runs right and left in the scene. If we had done that, part of the model would be crushed flat. The popup help for this button says that it "aligns the model with its local YZ plane". That's accurate, but it may not help you.

    Try this: we don't dwell on it much, but every vertex in a model has an X, a Y, and a Z coordinate value. It has to: it's in a 3D graph. When you click the Align tab's X button, the selected vertices all have their X values set to zero. The Y and Z values are left alone. So we have a set of points that are located at various places in YZ space, that have all been moved so their X values are 0. This would not be useful for all points in an object, but it is a good tool to move a set of points so they all match on one dimension in the middle of the scene. Obviously, this is also not useful if the YZ plane is not in the desired center of the model. If your model is in the wrong place in the scene, it needs to be moved before using the Align function.

  9. Leave the vertices selected. Go back to the Graphite ribbon, Vertices tab, and open the Weld Settings caddy.
    The last weld threshold value you used is probably too big this time. How can you tell? Follow the advice in the text. Run the value way up, say to 100. Notice that some vertices above and below each other on the centerline will now be welded together. Bad idea!
    Run the value for weld threshold down until there are no unintended welds taking place. Then, finally, click the Check Mark to complete the weld. Now the two model halves do share geometry, and the model can be manipulated as one body.
  10. Save incrementally and show me the work.

Project Exercise 2: Creating the Accessories 

The exercise starts by telling you to open either your last file or a the version 6 file from the download set. As usual, it is better to continue with your last file if possible. Loading the supplied files can teach you some skills, but it does not demonstrate that you are using them. We will hit a point later that may force us to use the provided files

The text tells us that we will use map textures for most of the detail to come on the soldier, but that we should add specific enhancements now, like pads and equipment pouches, to improve the character's silhouette. Do you recall why we care about that?

A standard guideline for animations is to make every character unique enough that we can tell which one is which just by their silhouette, in other words, by their shape. This does not mean that every soldier on Omaha Beach needs to have a unique look. The extras can look like extras. The characters, the ones who drive the story, should each have their own look and shape.

This is related to the discussion of silhouettes and motion on page 84 in Wyatt. The first step in understanding a character's motion is recognizing the character. If we understand who is doing something, it is easier to understand what they are doing. When you block a scene, do it so that the character can be recognized, and so the character's action in the scene adds to the viewer/player's understanding and enjoyment of what is happening.

Back to the exercise in Derakhshani, which is making the character more recognizable:

  1. The first item to make is a belt. It would be nice see some reference art, wouldn't it? Look at the images on pages 249 and 252. Breathe, too. The detail level in the pictures may make you a little nervous, but it is better to see them to get an idea of where we are going.

    This is a more normal situation, by the way. No one is going to tell you to make a model of a character without first having you develop reference art for that character, or giving you that reference art. If we were doing this modeling job for a real production, the lead designer would have either given the art to you first, or asked you to develop it and have it approved before modeling it.

    Would it have helped to have seen that art before you even started modeling? Yes. I suspect you were not given that information because the authors wanted to focus on the software interface first, without burdening you with the choices they made for you.

    It is time to think about such things, to grow as a designer and a modeler.

    "When I was a child, I spoke like a child, I thought like a child, I reasoned like a child. When I became a man, I gave up childish ways."

    Back to that belt. Select a loop of edges that are a sensible starting border for a belt.
  2. Open the Chamfer settings caddy as instructed in the text. Set the Amount to 1.5 and click the Check Mark button. (The belt will be 1.5 inches high.)
  3. Now you have the original loop and the chamfered loop selected. The text is a little unclear. Let's make it easy.
    Hold down a shift key, and switch to Polygon mode. This should select the polygons bordered by your two edge loops. The text is not sure this will work. It did for me. If it does not work for you, ctrl-click the appropriate polygons to select them.
  4. Open the Polygon Extrude Settings caddy as instructed. Now, something new: change the default Group setting to Local Normal. This means to extrude along a set of lines that are perpendicular to the surfaces of the polygons. (Yes, I am speaking English.) In this case, that means "out from the body". Make the change, and watch how the belt changes shape and direction. Set the Height value to 0.5 (thickness of the belt) and click the Check Mark button.

  5. This step begins the construction of a belt pouch. Select and delete two polygons from the belt, as indicated by the lower picture on page 170. Ignore the lines on the picture until the next step.
  6. Select the four large polygons that are in the body surface above and below the belt, shown in the second picture on page 170.
    Open the Polygon Extrude Settings caddy. Since you just used it, it is already set to extrude a half inch. In fact, it has already done it, but it would be happy to change if you changed the settings.
    Click the Plus sign to accept and continue. The caddy applies the last used setting once again, which is just what you want. Click the Check Mark button to accept the change and close the caddy.
  7. Examine the picture in the middle of page 171. Select the eight polygons indicated in the image and in the text. and delete them. They do not have to be deleted together, which is good, since you will probably have to orbit and zoom to be able to see them all.
  8. Go to Edge mode. Select the open edges of the top and bottom section of the pouch.
    Open the Edges Bridge caddy.
    The text says to accept the default values. Sorry, we can't do that. Most of us used the bridge tool already, so it will be displaying the last used settings, not the default settings. I had to use a magnifying glass to read the settings in the text. After applying them to my caddy, I captured them in a screen shot. which is displayed on the right. Use the settings in the image on the right, then click the Check Mark button.

    If the bridge does not form, you probably do not have all the correct edges selected. The number of selected edges on each side of the gap need to match. Examine your selection, confer with other students if necessary, and try again.

    If your pouch does not look like a regular rectangle, select and move appropriate vertices so that it does. As the text says on page 172, once the pouch is the right shape, select the surface polygons and move them away from the body to give the pouch more depth. In other words, make it thicker. A pouch so thin that it could only hold one document would not be of much use to a soldier.
  9. This step begins construction of cutouts in the soldier's kevlar vest. Examine the image on the bottom of page 172. Select six polygons as indicated on both the right and left sides of the body. (The text does not mention both sides explicitly, but it does say "under the arms", so that means both sides.) Do not delete them.
  10. Open the Polygons Bevel Settings caddy. Use a Height of -0.5 and an Outline of -1.0.

    The text suggests moving vertices if you are not satisfied with the outcome. I went back a few steps and inserted a new Swift Loop to be able to bevel more polygons, getting closer to the image in the text. You may want to do so as well. This is another moment where prior knowledge of the design would have helped. If only we had known about this desired bevel when we were sculpting the polygons on the model. Don't worry about the shape being inexact, just make it the best you can from here. A unique feature on your model is a good thing for me at this time.

  11. This step begins the construction of a leg strap and a holster. A little modification is needed here. The text says to add a leg strap for a holster to both legs. Their model has only one loop on it later, so that will be fine here.
    1. Use the Swift Loop tool to add a new edge loop to the model's right leg. Locate the loop below the groin level, but above the knee level.
    2. As the book says, the loop will be crooked when you add it. Do not turn off the Swift Loop tool. Hold down Ctrl and Alt, and drag the loop to fix it. The loop will reform higher up on the body, but you can drag it down to the level where you want it.
  12. On the modified leg, select one edge from the new loop of edges. (Wonder of wonders, they said the right leg, and they actually mean the model's right leg. Be warned: the author's have now used both meanings for right and left!)
    Go to the Graphite ribbon, Modify Selection tab, and click the Loop button. Go to the Edges tab and open the Chamfer settings caddy. Set your amount to 1.5 and click the Check Mark button. Your loop is now two loops.
  13. This one is worded badly. You just did a Chamfer, so both edge loops of the chamfer area should be selected. Do not go to Polygon mode as the step indicates in the first three words. Instead, hold down a shift key and click the Polygon mode button on either the Graphite ribbon or the Modify panel. The polygons between the chamfer loops should be selected. (Note: this will not work if you try to do it by clicking the word "Polygon" in the Modifier list. Why? Selecting in the Modifier list with Ctrl or Shift tends to select multiple items [subobject types] in that list. Not what we want this time.)
  14. Examine the illustration on page 174. The text wants you to delete a strip of polygons from the leg as shown. Do not delete them. I could not get the model to work the way it appears to work in the remaining steps in the text. Modify the rest of this exercise with the following instructions.
    Instead of deleting them, select the polygons between the leg strap and the belt. Extrude them a half inch on their local normals.
  15. Skip this step.
  16. Skip this step.
  17. Forget the isolation mode in this step. Exit subobject mode. Create a plane as indicated, and move it to the relative position shown in the bottom illustration on page 175.
  18. Convert the plane to an editable poly. The dimensions given in the last step may not fit well. Scale it if needed. Move vertices so that the polygon has a holster shape as shown.
  19. Add a shell modifier as instructed, with the properties given in the text. The holster will now be thicker, but the leg strap is wrong. In the Front viewport, move the holster close to the leg, Select the body, and return to Edge mode.
    Now, select an outside edge that runs horizontally on the leg strap. It needs to be an edge that runs from front to back, not left to right. The edge will become the top of a mounting surface for the holster.

    Select an edge on strap. The selected edge is not visible here, but its Move gizmo is. Move the edge to create a vertical surface Move the holster next to the mounting surface.


    Move the selected edge to the left, to establish a mounting surface for the holster that is close to vertical. Leave subobject mode.
    Move the holster next to the mounting surface.
  20. Select the body. Go to the Graphite ribbon. On the Geometry (All) tab click the Attach button, and select the holster. It becomes part of the model. Save incrementally and show me your work.

Project Exercise 3: Boots 

The exercise starts by warning you that the authors will use fewer words in their instructions, presuming that you are familiar with the controls we have seen in this chapter.

  1. Create a cylinder in the Perspective viewport. Try something a bit different. Draw it by hand first, then use the modify panel to adjust to the parameters given. Where it says to adjust the number of Height segments to 1, just right click the spinner for that parameter. It will go to 1 automatically. Right clicking a spinner control will set the associated value to the minimum allowed value.
  2. Convert the cylinder to an Editable Poly. In the next step, the text tells you to delete the round polygons at the top and bottom of the cylinder. Delete them now.
    Move the new poly object to become the top of the left boot. It will be modified to fit the reference art next.
  3. Move vertices as the text says. As with the leg, try moving a marquee selection of vertices instead of one at a time. Moving a single column of vertices tends to make sharp edges, moving areas of vertices makes more rounded figures. The polygons it wants you to delete here are the ones I had you delete in the last step. You could not have selected the top one easily in this step after you moved the object under the leg.
  4. As the text says, select all the bottom edges of the cylinder except the two that would lead to the tongue of the boot. It may be a good idea to select these edges in a rotated Perspective viewport, and to work with them in the Right viewport. Use the Move tool to shift-drag the edges down to the level of the sole of the boot.
  5. Select the two edges you left alone in the last step. Shift-drag the move tool four times to create four new sets of polygons, as indicated in the pictures on page 177. You will want to use the free movement square on the move gizmo, rather than the arrow handles for the first three sets of polygons.
  6. Your reference for this step is the bottom left picture on page 177. Select the edges shown in red in that picture. Use the Bridge tool to make a three segment bridge on the left side of the boot, then repeat the process on the right side of the boot.
  7. There will be vertices that are in the wrong place after the last step. Note the two vertices shown in red in the image below.


    Those vertices are in red because I just selected them with a marquee selection. (I could have ctrl-clicked them instead.) Find your vertices in similar states, select them and weld them with a Threshold of 2.0 as the book says.
  8. Use the Swift Loop tool to add a loop of edges as shown in the picture on page 178.
  9. Follow the instructions in this step to use a chamfer to split the central line of edges from the top of the tongue to the toe cap. A suggestion: the value given in the text for Amount was not enough on my model. I increased it to 1.5.
  10. Chamfer the back vertical edge of the boot that runs from the heel to the topline. (What, haven't you ever worked in a shoe store?)
    The authors set a new standard for telling you to use your own methods in this step. They tell us that the boot is boxy, so we should "scale in the vertices and smooth out the sides" to resemble the picture at the top of page 179. They seem to have forgotten to mention adding the new loop of edges around the throat of the boot (the ankle covering) much less adding any useful instructions for shaping the boot.
    Add another Swift Loop as shown in that picture, and adjust vertices to the best positions you can. I suppose this step will tell us how much modeling skill you have at this time.

    Boots AttachedWhen it is as good as it will get, review the instructions you were given previously to accomplish the following:
    1. Move the pivot point of the boot left until it matches the center of the body.
    2. Mirror the boot as a copy.
    3. Adjust both boots as needed.
    4. Attach the body to the boots.
  11. Save incrementally and show me the work.

Project Exercise 4: Hands 

  1. Create a new box as the text says. I continued to have a problem with the dimensions given. If you do as well, make the box as instructed to get the proportions right, then scale it as needed. I recommend making the box in a different viewport, but you might want to try it in the Perspective view to see what happens. You can make it, but you may not be able to find it or locate it where you want it. If this goes wrong, start over in a different viewport.
    When the box is the right size and at the end of the model's left wrist, convert it to an Editable Poly.
  2. Add Swift Loops as instructed: in the top view, two vertical and two horizontal. (You could have added segments when the box was created, but this gives you practice in free hand modeling.) Refer to the picture on page 180, and move columns of vertices to match it.
  3. Step 3 says to delete the polygons on the hand where it meets the wrist. This will be difficult unless you remember that you can isolate the hand, which makes it much easier.
  4. Go to Edge mode. Select the loops of edges that run around the top and the bottom surfaces of the hand and chamfer them to 0.7. The Loop tool did not want to complete the loops on my model, so I manually selected the missing edges before using the Chamfer tool. Once the chamfer is applied, your model should look like the pictures on page 181.
  5. Add another Swift Loop of edges as shown in the second picture on page 181.
  6. Go to Polygon mode. Use the Front or Perspective viewport to select the three polygons shown in the image below.

    Polygons to form thumb

    Apply the Extrude settings given in the text.
  7. This step is a bit hard to follow. Try this: scale the large polygon down a bit. Bevel it out to form a knuckle, using Height for the length, and Amount for the size at the end of the bevel. Rotate it to approximate a good angle. Repeat for the last section of the thumb.
  8. Skip
  9. This one is funny as well. Try to follow the directions, but experiment with the Scale tool, the Move tool, selections of Edges and Vertices instead of Polygons, and vary the amount of falloff for the Soft Selection mode. You want the top surface of the hand to taper down as it approaches the fingertips. This begs a question. Where are the fingers? This is a low polygon count model. The fingers will be faked by adding a map to the mitten.



  10. As before, move, scale, and otherwise adjust as best you can. When you are ready, move the object's pivot point as you did for the boot, mirror the object, adjust again if needed, and attach the body to the hands.
  11. Save incrementally and show me the body.