Motion Settings
From ShadeCamp
Here you will start learning how to use the Motion window.
Let’s study the techniques used to control the Sequence Path using Motion Points and Sequence Key Points.
Using the Motion Window
In Shade animations, you start by creating several joints, and setting the joints so that they control your objects (you have already learned about this in Chapter 17). Next, you specify the movements (motions) for the objects over time. You make these settings by changing the joint values according to a time sequence. The Motion settings are made in the Motion window.
You can manually change the joint values, but the Motion window allows you to change the joint values automatically according to their Sequencing Timing value settings. With the animation Rendering function, you can produce 3DCG animations in which the objects created in Shade come to life!
Now you will start learning how to use the Motion window.
Creating a Shape and Joint
The shape and joint you will create here are very simple, since your job is to get familiar with the usage of the Motion window.
1. Let’s create a Sphere object inside a Rotator Joint as shown in the figure below.
Creating a Rotator Joint (to contain a Sphere object) by dragging upward from the origin in the Side view.
A Rotator Joint is made by dragging upward from the origin.
2. Check the Browser to be sure that the Sphere has been created inside the Rotator Joint.
Changing the Joint Value slider in the Object Info window (by dragging up and down) will make the Sphere rotate around the Rotator Joint, using the Joint as the axis of rotation.
After checking the movement of the sphere, reset the Joint Value slider to 0.00.
Switching to the Motion Setting Window
1. Display the Motion window and turn on the Sequence checkbox in the upper left corner of the window.
While the state in which you create and model objects is called the “Object Modeling mode,” the state used to specify motion is called the “Motion Setting mode,” which you enter by turning on the Sequence checkbox.
You can set the joint values using the Joint Value slider on the left side of the Motion window.
IMPORTANT: In Shade, the Joint Value slider of the “Object Modeling mode” is called the “Current Joint Value” slider, while the Joint Value slider of the “Motion Setting mode” is called the “Sequence Joint Value” slider.
Regardless of whether the Sequence checkbox is on or off, the Joint Value slider on the left side of the Motion window is always active. This slider toggles between the Current Joint Value slider (when the Sequence checkbox is off) and the Sequence Joint Value slider (when the Sequence checkbox is on).
Current Joint Value slider is displayed with the Sequence checkbox is off
Sequence Joint Value slider is displayed with the Sequence checkbox is on.
When the Sequence checkbox is turned on, the Sequence Cursor on the Sequence Ruler changes color and becomes active. In this mode, the Figure window displays the objects at the time sequence position indicated by the Sequence Cursor and the Sequence Cursor Value text box.
Part names with the Sequence checkbox off and on
Check that the Sequence checkbox is on, and continue with the next section.
Setting the Total Number of Frames for the Animation
1. Press the Settings button in the upper left of the Motion windows to open the Animation Settings dialog box.
2. Set the Total Frames to 60 and the Frame Rate to 15. The other settings should not be changed from their default values. Check these settings and press OK.
Animation Settings dialog box
Magnifying and Shrinking the Active Motion Box
Since the number of frames has been reduced from 300 to 60, the Active Motion box becomes smaller. The size of the Active Motion box can be adjusted using the + and - buttons located at the upper left of the Motion window.
Adjusting the size of the Active Motion box
Note: If you click the + button or - button with the Ctrl (Win) / option (Mac) pressed, the box size is doubled or halved. Clicking the + or - button while holding the Shift key returns the box to the normal (X 1) size.
Creating a Point
1. Check that the Rotator is selected in the Joint Selection box at the lower left of the Motion window. Click at the location indicated in the figure below within the Sequence Key box, while holding down the Z key (Win) / option (Mac).
A Sequence Key Point is created In the Sequence Key box, and a Motion Point is created in the Active Motion box.
Sometimes the Sequence Key Points and Motion Points are generically just called “Points.”
Moving a Point
1. Drag the Sequence Key Point to place it on frame 5.
The Sequence Key Point and the Motion Point move together. Dragging the Sequence Key Point or the Motion Point changes the values in the Motion Point Value text box in the middle left of the Motion window accordingly. The Motion Point Value text box will display the sequencing time of the selected Point.
Updating the Sequence Joint Value Using the Slider
1. Check that the created Sequence Key Point is selected, and drag the Sequence Joint Value slider on the left side of the Motion window.
The Motion Point does not follow the slider.
2. Switch on the Auto Key checkbox at the upper left of the Motion window and drag the Sequence Joint Value slider.
The Motion Point follows the slider.
Note: If you want to modify a Sequence Joint value once it has been set for any Motion Point, be sure the Auto Key checkbox is on before you make any changes. When the Auto Key checkbox is on, the modified Sequence Joint value will be updated for the Motion Point when the Point is located at the same position as the Sequence Cursor.
3. Set the Sequence Joint value to “36”.
Set the Sequence Joint value to “36”
Creating a Point Using Auto Key
1. With the Auto Key checkbox on, drag the Sequence Cursor on the Sequence Ruler to place it at frame 54.
Drag the Sequence Cursor to place it on frame 54
Dragging the Sequence Cursor changes the value in the Sequence Cursor Value text box (in the upper left of the Motion window) accordingly. (In this case, the Figure window displays the state of the time sequencing position indicated by the Sequence Cursor and the Sequence Cursor Value text box.) When the Sequence Key Point is selected, the Sequence Cursor also moves to the position where the Point is selected. When the Sequence Key Point is selected, the Sequence Cursor becomes black. When the Sequence Key Point is not selected, the Sequence Cursor becomes hollow.
2. Drag the Sequence Joint Value slider to set the value to “180”.
Set the Sequence Joint Value slider to 180
A new Sequence Key Point and Motion Point are automatically created. With the Auto Key checkbox on, a Motion Point and Sequence Key Point are automatically created for the joint whose Sequence Joint value is modified, when a Point is not located at the same position as the Sequence Cursor.
Previewing the Motion
1. Drag the Sequence Cursor to the left and right.
The value in the Sequence Cursor Value text box varies accordingly. In the Figure window you will see the Sphere revolve around the Rotator joint (using the joint as the axis of rotation) as you drag the Sequence Cursor.
Revolving sphere
The Sequence Joint Value slider and Sequence Joint Value text box display the joint value at the point where a vertical line drawn straight down from the Sequence cursor contacts the Sequence Path.
You can preview the motion using the Sequence Controllers. For more information on the Sequence Controllers, refer to the Shade Reference.
Adding a Point in the Active Motion Box
You will now add another Point.
Moving the mouse cursor within the Active Motion box changes the value in the Sequence Value text box in the upper part of the Motion window. The Sequence Value text box shows the position of the mouse cursor whenever it is within the Sequence Ruler, Sequence Key box, or Active Motion box.
Moving the mouse cursor within the Active Motion box changes the value in the Sequence Value text box
1. Within the Active Motion box, Z key + click (Win) / option + click (Mac) the area where the Sequence Value text box indicates “25”, then drag to add a new Point with a Motion Point value of “25”, Sequence Joint value of “-150”.
Z key + click (Win) / Option key + click (Mac) the Sequence Value to 25 within the Active Motion box
And drag the mouse to set the Sequence Joint value to -150
By adding a new Point, the Sequence Path becomes a smooth curved line. Check the animation by previewing it.
Modifying the Tangent Handles of a Motion Point
When you added the Motion Point in the previous section, you may have noticed that the tangent handles were also created automatically.
By using these tangent handles, you can control the Sequence Path before and after the Motion Point.
1. Move the tangent handles of the middle Motion Point and check to see how the Sequence Path changes.
When modifying a tangent handle, the Auto Smooth checkbox is turned off automatically, which means the automatic smoothing will not be performed.
You cannot delete the tangent handles of a Motion Point. To make a straight Sequence Path, the Cusp checkbox (described later) will be used.
Before proceeding to the next page, switch the Auto Smooth checkbox on again.
Forming an Angle in the Sequence Path Using the Cusp Checkbox
1. Select the newly added Sequence Key Point and click on the Cusp checkbox located at the upper left of the Motion window.
Click on the Cusp checkbox
Points with the Cusp checkbox on are sometimes referred to as “Corner-on Points.” At Corner-on Points, the Sequence Path will form a sharp angle, and the Sequence Path between Corner-on Points will be a straight line.
In the case of Corner-on Points, you can modify the tangent handles independently.
2. Before going on, check that the new Sequence Key Point is still selected, and turn off the Cusp checkbox.
Now let’s take a look at the bottom of the Motion window. This area is called the “Motion List” and is used to check time positions of multiple Joints at one time.
Motion List
3. In the Motion List, drag the selected Sequence Key Point left and right.
In the Motion List, drag the Sequence Key Point left and right
You can see that dragging a Point in the Motion List will move the corresponding Point in the Sequence Path of the Active Motion box in a horizontal direction.
Deleting a Point
1. Select the Point you want to delete and click the Delete button located in the upper right of the Motion window.
Select the Point and click the Delete button
The Sequence Key Point and all associated Motion Points are deleted.
The Point is deleted
Adding a Point on the Sequence Path
1. Drag the Sequence Cursor to frame 40.
When dragging, you can see the value of the left-side Sequence Joint Value slider changing according to the Sequence Path.
2. Within the Sequence Key box, Z key + click (Win) / option + click (Mac) the area near frame 40.
By dragging the Sequence Cursor, the Sequence Joint Value slider and Sequence Joint Value text box are set to the joint value at the point where a vertical line drawn straight down from the Sequence cursor contacts the Sequence Path. If you create a Point at the frame with the Sequence Cursor, the Point appears on the Sequence Path.
Changing Just the Point Value, or Just the Joint Value
When changing the Motion Point value and the Sequence Joint value together, you can drag Points in the Active Motion box. Here we provide a variation on this procedure.
To change the Motion Point value only and leave the Sequence Joint value unchanged:
Drag the Sequence Key Point to the right or left, or drag the Motion Point to the right or left in the Motion List.
2. To change just the Sequence Joint value and leave the Motion Point value unchanged:
Turn the Auto Key checkbox on and drag the Sequence Joint Value slider up or down. Only the the Sequence Joint value changes. The Auto Key checkbox must be on in order to update the Sequence Joint value.
Besides the methods explained above, the Sequence Joint value and Motion Point value can be changed by entering values directly in their value boxes.
Click in the Motion Point Value text box or the Sequence Joint Value text box to highlight the value, and directly enter a new value. (For this method also, updating the Sequence Joint value is only allowed when the Cusp checkbox is turned on.)
Limiting the Range of Sequence Joint Values
1. Open the sample file "UG_18_motion.shd."
2. Select Translate from the Part tool in the Toolbox
Creating a Joint
We will now use another sample object. Open the Make_Joint.shd file from the Chapter 19 folder in the User Guide folder.
1. Select Part tool/Slider and create a Slider joint by dragging from point A to B in the Front view.
The perspective view is displayed with quick-rendering (Shading) and wireframe on.
Point A is the center of the Sphere, Point B is located a distance equal to the radius of the Sphere away from the right wall.
2. In the Browser, change the hierarchical structure so that the Sphere is included in the Slider Joint, select Slider (slider joint), and check to see that moving the Current Joint Value slider in the Object Info window makes the Sphere move along the Slider.
When the Joint value of the Current Joint slider is negative, the Sphere will pass through the left wall. Also, if the Slider Joint is too long or too short, the Sphere may pass through the right wall or stop too far away from it. To increase our productivity we must plan carefully when creating models by keeping in mind the relationships of the desired Motion Settings.
All Joint Value sliders (except for the Ball Joint) have a “Joint value upper limiter” and a “Joint Value lower limiter,” which restrict the movement of the slider. Use the Range checkbox on the right side of the slider to set whether you will use the limiters or not.
In this particular case, we will use the Joint value lower limiter so that the Joint value can not go negative.
3. With the Current Joint value set at 0.00, drag the Joint value lower limiter up.
By moving the Joint value lower limiter up, the Joint Value slider is limited to values between 0.00 and 1.00.
Now we are ready to move on to the Motion setting procedure. Name the object file and save it.
Creating the Sequence Key Points
1. Choose the View menu / Motion to open the Motion window.
2. Space + X key + click (Win) or Space + }{ + click (Mac) in the Active Motion box to enlarge the display a few times.
Note: You can magnify the view with the Space + X key + click (Win) / Space + }{ + click (Mac) in the Active Motion box, and shrink the view with the Space + Ctrl + click (Win) / }{ + option +click (Mac).
3. Click the Sequence checkbox to switch from the Object Modeling mode to the Motion Setting mode.
As described in the previous chapter, the Motion Setting mode allows you to set the joint value using the Sequence Joint Value slider located on the left side of the Motion window. In the Motion Setting mode, all joints in the Figure window will display values at the current Sequence Cursor position. There is no time concept in the Object Modeling mode.
4. Create three Sequence Key Points by clicking in the Sequence Key box. Z key + click (Win) or option + click (Mac) in the Sequence Key box.
The values for the first Point should be Motion Point value 0 / Sequence Joint value 0.0, for the second Motion Point value 10 / Sequence Joint value 1.0, and for the third Motion Point value 20 / Sequence Joint value 0.0. (To set the second Point, click the Auto Key checkbox and drag the Sequence Joint Value slider to 1.0.
Creating the Corner-on Points
This time you will create all Points as Corner-on points.
1. Starting inside the Sequence Key Box, drag around the Sequence Key points to select all three.
Click the Cusp checkbox at the left to make them Corner-on Points.
All the Motion Points of the Slider joint become Corner-on Points.
Check the Motion setting you have just made using the Sequence Controller. You have completed the Motion settings for a Sphere which moves right – left at a constant speed.
Using the Ease in / Ease out Sliders
1. Select the first Motion Point and move the Ease out slider located on the left side of the Motion window to the far right position.
Notice how the Sequence Path now curves.
The Ease out slider controls the Joint value from the selected Point to the next Point, and has a maximum Ease out effect at the far right position. A Ease out effect creates a Sequence Path in which a Joint value will change gradually at the start, and reach a maximum speed right before the next Point. It gives an acceleration to the movement, beginning with slowly moving away from the selected Point.
Preview how this Sequence Path affects the object movement.
2. Select the third Motion Point, and move the Ease in slider located on the left side of the Motion window to the maximum right position.
Notice that the Sequence Path has changed again.
The Ease in slider controls the Joint value from the Point before the selected Point up to the selected Point, and has a maximum Ease in effect at the far right position. The opposite of the Ease out effect, a Ease in effect creates a Sequence Path in which the Joint value changes fastest at the start and slows down to a minimum just before the next Point. The Ease in effect will give the impression of a rapid start, then a deceleration to a slow stop.
Preview how this Sequence Path affects the object movement.
Making a Motion Setting for a Multiple Joint Object
Here, you will make a Motion setting for an organic object.
1. Open the Arm.shd file from the Chapter20 folder within the User Guide folder.
The "Arm.shd" scene.
The object is shaped like the arm created in Chapter 17. Ball joints and a Uni-Scale joint are already incorporated in this object and the Skin setting is also completed.
In this chapter, we will start with the Motion setting for the object. As for the Skin setting for the joint, review Chapter 17.
Preparing the Motion Setting
Before starting the Motion setting, let’s think about how the object moves.
Here, you will make a setting so that the object moves as shown in the diagram below, using the same procedure for moving the object with the Skin setting.
1. Initial state
2. Bending
3. Stretching out
4. Bending again
5. Initial state
In this chapter, we will use two different procedures to complete the same Motion setting. The created movies are almost the same, but the approaches to completing the Motion setting are different. After going through both procedures, you can use whichever suits you.
Making the Motion Setting with the Auto Key Checkbox Off
The flow is as follows:
1. Set each Pose (each joint value)
2. Move the Sequence Cursor
3. Create Sequence Key Points by clicking
Repeat the above procedure.
Now, let’s start setting the Motion.
1. Choose the View menu / Motion to open the Motion window.
The movie you will be making will be approximately 40 frames long, so click the + button to enlarge the Active Motion box to achieve an efficient work space.
Note: You can magnify the view with the Space key + X key + click (Win) / Space key + }{ key + click (Mac) in the Active Motion box, and shrink the view with the Space key + Ctrl key + click (Win) / Space key + option key + click (Mac).
2. Select the Sequence checkbox to enter the Motion Setting mode. Confirm that the Auto Key checkbox is off.
Recording the First Pose
1. Initial state.
After opening the file, you will find that every joint value is set to 0.00 for the object in the Figure window.
If any joint value is not set to 0.00, turn off the Sequence checkbox to enter into the Object Modeling mode, display the contextual menu, and select Reset All Joints to reset all joint values to 0.00. After that, reselect the Sequence checkbox to enter the Motion Setting mode.
IMPORTANT: Only the Object Modeling mode allows you to use the contextual menu within the Browser to Reset All Joints.
To record this state at Sequence frame 0, create a Sequence Key Point.
1. Select Ball Joint A from the lower-left Joint Selection box and create a Sequence Key Point by Z key + clicking (Win) / option key + clicking (Mac) frame 0 within the Sequence Key box, while checking the position using the Sequence Value text box.
You have now finished recording the first Pose.
Recording the Second Pose
2. Bending
In this Pose, the arm has been bent, with the upper arm muscle bulging.
1. Select Ball Joint D in the Joint Selection box at the lower left of the Motion window and choose Toolbox / Move tool / Ball Joint A.
Note: When you hold down the Ctrl key (Win) / option key (Mac) and chose the Toolbox / Move tool / Ball Joint, you can operate inverse kinematics continuously without choosing Ball Joint again. If you want to move to another operation, click the finish button in the Toolbox, or press the Enter key.
2. In the Front view of the Figure window, drag the selected Ball Joint D and pose the object as shown in the figure below.
3. To record this state, Z key + click (Win) / option key + click (Mac) frame 10 on the Sequence Ruler (Note: Do not click within the Sequence Key box).
Even if Ball Joint A is not selected in the lower-left Joint Selection box, a Motion Point is created for every joint except Uni-Scale E, and the Sequence Key Point is set for Ball Joint A in the top most hierarchy.
IMPORTANT: If you create a Sequence Key Point by Z key + clicking (Win) / option key + clicking (Mac) within the Sequence Key box, a Motion Point is created for every joint within the selected joint. If you create the Sequence Key Point by Z key + clicking (Win) / option key + clicking (Mac) on the Sequence Ruler, only the Motion Point whose joint value changes from that of Motion Point contained in the previous Sequence Key Point is created. For the above reason, a Motion Point is not created for Uni-Scale E whose joint value does not change.
When recording the first Pose, you have created a Sequence Key Point by clicking within the Sequence Key box, not on the Sequence Ruler. The reason for this is that the Points are not created if you click on the Sequence Ruler, because the previous Sequence Key Point does not exist and thus no change is made to the joint values (hereafter “Point” is a generic name for both “Sequence Key Point” and “Motion Point”).
In the Active Motion box, the Sequence Path remains level, although the joint value has changed.
IMPORTANT: You can move the Motion Point of a ball joint along the Sequence horizontally, but not vertically. You can check the Sequence value from the Motion Point of the Ball joint, but cannot verify the specific joint value. However, the Motion Point of the ball joint properly records its joint value at that time for the ball joint. Therefore, you cannot actually change the Sequence Path for ball joints, but can update the joint value using the inverse kinematics function. You can also use the Cusp checkbox and the Ease in / Ease out functions.
To set the Pose shown in the diagram below, you have to move Uni-Scale E as well.
IMPORTANT: To make changes to the Point you have set, be sure to turn on the Auto Key checkbox and place the Sequence Cursor at the same position as the Sequence Key Point that is to be changed.
If the Sequence Cursor is not at the second Sequence Key Point, click the Sequence Key Point to place the Sequence Cursor there.
4. Turn on the Auto Key checkbox in the upper left of the Motion window.
5. Select Uni-Scale E in the lower-left Joint Selection box and drag the Sequence Joint Value slider up to 1.20.
Because the joint value was changed, a Motion Point for Uni-Scale E is automatically created. The Motion Point is created so that it follows the second Sequence Key Point, since the Sequence Cursor is set at the same position as the Sequence Key Point.
You have finished recording the second Pose.
Since the Auto Key checkbox is currently on, let’s make the Motion setting for the third and later Poses with this checkbox on.
Making a Motion Setting with the Auto Key Checkbox On
Now, let’s continue to make the setting and start from the third Pose.
The flow is as follows:
1. Move the Sequence Cursor 2. Set each Pose (each joint value) 3. Sequence Key Points are created automatically
Recording the Third Pose
3. Stretching out
In the third Pose, the arm has just stretched out.
1. To record this state at Sequence frame 20, drag the Sequence Cursor to frame 20.
2. Select Ball Joint D from the lower-left Joint Selection box, choose the Toolbox / Move tool / Ball Joint A, and drag Ball Joint D in the Front view of Figure window to pose the object as shown in the below figure.
3. Next, select Uni-Scale E and drag the Sequence Joint Value slider to 1.00.
Since all joint values have changed from the previous Sequence Key Point, a Motion Point is generated for every joint automatically.
The third Pose has been recorded.
Recording the Fourth Pose
4. Bending again
In this Pose, the arm has just swung upward and bent again.
1. To record this state at Sequence frame 30, move the Sequence Cursor to frame 30.
2. Select Ball Joint D in the lower-left Joint Selection box, choose the Toolbox / Move tool / Ball Joint A while pressing the Ctrl key (Win) / option key (Mac), and drag Ball Joint D in the Top view of the Figure window to pose the object as shown in the figure below.
A Motion Point is generated only for those joints whose values have been changed.
3. Next, drag it upward in the Front view.
4. A Motion Point is automatically saved for each updated joint value.
The fourth Pose has been recorded.
Recording the Last Pose
5. Initial state
The procedure of the last Pose is omitted here since it is exactly the same as that of the first Pose. Try to make the setting by remembering what you have learned so far
Checking the Result and Creating the Animation
After previewing the motion using the Sequence Controller to check that everything is OK, let’s create a movie file by rendering the animation based on the settings that have been made so far.
1. Choose the Rendering menu / Create Animation … to open the Animation Settings dialog box.
In the Animation Settings dialog box, enter 0 in the “From” text box, and 40 in the “To” text box. Leave all other values at the defaults.
The folder and the file name in the Save dialog box, and the Compression Settings, can be specified as you like.
3. Select the second Motion Point, and move both the Ease in and Ease out sliders to the maximum right positions. You can probably imagine the result here. When there is a Ease out effect assigned to a certain Point, and a Ease in effect assigned to the next Point, the Sequence Path between the two Points forms an S-shaped curve.
Preview how this Sequence Path affects the object movement.
Creating a Path Using a Ball Joint
When you set a path for a Ball joint, you can do it with either of the two procedures (with the Auto Key checkbox on or off) described in the previous chapter. Since we will provide both procedures in this chapter, make the Motion setting with whichever procedure you like.
1 .Open “ UG_18_path.shd ” from the "Documentation - Sample" tab in ShadeExplorer.
The "Path.shd" file
The object is a sphere on a floor.
Let’s set a Path to make the sphere bounce.
2. Choose the Toolbox / Part tool / Ball Joint. Click on the Ruler to fix the Y-coordinate of the 3D cursor, and drag from Point A in the Top view to create a Ball joint at the center of the sphere.
3. In the Browser, move the sphere into the Ball joint you have created, as shown in the figure below. You have now finished setting the joint. Next, let’s set a Path in the Motion window.
Before starting to set a Path, let’s think about how the sphere will bounce.
4. Here you will create a motion in which the bounce becomes weaker, and finally stops, as shown in the figure below.
5. Choose the View menu / Motion to open the Motion window.
Enlarge the view to achieve an efficient work space.
6. Select the Sequence checkbox to enter into the Motion Setting mode.
With the Auto Key Checkbox Turned Off
Now, record the first position.
1. Select Ball Joint in the Joint Selection box and choose the Toolbox / Move tool / Offset.
In the Side view, drag the joint as shown in the figure above.
2. Z key + click (Win) / option key + click (Mac) within the Sequence Key box to record the first position.
Similarly, record the other positions by repeating the previous procedure, following the sequence (2, 2’, 3, 3’ ...) as shown on the next page.
3. Choose the Toolbox / Move tool / Offset, drag the joint in the Figure window to each numbered position, and then Z key + click (Win) / option key + click (Mac) within the Sequence Key box or on the Sequence Ruler to record each position. Repeat this procedure following the numbers (2, 2’, 3, 3’ …) shown in the figures below.
Note: If you hold down the Ctrl key (Win) / option key (Mac) and choose the Toolbox / Move tool/ Offset, you can perform the Offset function continuously without choosing Offset again. When you are finished, click the finish button in the Toolbox, or press the Enter key.
With the Auto Key Checkbox Turned On
You will record the first position.
1. Move the Sequence Cursor to the frame at which you will record the first position.
2. Select the Ball Joint in the Joint Selection box and choose the Toolbox / Move tool / Offset.
In the Side view, drag the joint as shown in the figure above.
On completion of dragging, a Motion Point is automatically generated.
Similarly, record the other positions by repeating the previous procedure, following the sequence (2, 2’, 3, 3’ ...) as shown on the next page.
3. Move the Sequence Cursor to the frame at which the position will be recorded. When you choose the Toolbox / Move tool / Offset and drag the joint in the Figure window, a Point is automatically generated in the Motion window. Repeat this procedure following the sequence (2, 2’, 3, 3’ …) shown in the figures below.
Note: If you hold down the Ctrl key (Win) / option key (Mac) and chose the Toolbox / Move tool / Offset, you can perform the Offset function continuously without choosing Offset again. When you are finished, click the finish button in the Toolbox, or press the Enter key.
The Procedure Common to Both Methods
The Path in the Figure window is a curved line without corners.
1. To select the multiple Sequence Key Points shown in the below figure, use the Ctrl key + click (Win) / }{ key + click (Mac) and then turn on the Cusp checkbox.
You can also select the Sequence Key Points by selecting the Control Points of the Path in the Figure window.
A corner is formed at each Corner-on Point on the Path, making the landing points for the sphere. Use the Sequence Controller and start the preview. When previewed, the object bounces monotonously.
Now let’s adjust the Path directly to set a more realistic bouncing motion.
2. Check that the Sequence checkbox and the Auto key checkbox are turned on, and drag the Sequence Cursor to frame 5.
3. Choose the Toolbox / Modify tool / Enter Modify Mode to enter the MODIFY mode.
4. In the Side view, drag each of the specified control points to adjust the Path as shown in the figure below.
Note: When the control points and the Ball joint overlap, you may select the center point of the Ball joint, instead of the control point of the Path. If you mistakenly drag the center point, the Ball joint as well as the whole Path will be moved. To prevent this, move the Sequence Cursor to a frame at which no Motion Point exists so as not to overlay the Ball joint on the control points of the Path.
When you finish adjusting the Path control points, observe the preview. You will notice that the object is bouncing at the same speed, and the speed for the straight portion of the Path is too fast. Let’s adjust the speed.
5. Move the Sequence Key Points to adjust the speed.
Sequence value for each Sequence Key Point)
For the smaller bounces, set a shorter Sequence Key Point interval to move the object faster. For the short straight line, set a longer interval to move the object slower. When previewed, the bouncing speed gets faster and slower before it stops.
After checking the motion in the preview, let’s create a movie file by rendering an animation based on the setting so far.
6. Choose the Rendering menu / Create Animation… to open the Animation Settings dialog box.
In the Animation Settings dialog box, enter 0 in the “From” text box, 70 in the “To” text box. Leave all other values at the defaults.
Directory and file name, and Compression Settings (that appear after pressing the OK button) can be specified as you like.
You have now completed a Path setting using a Ball joint.
Note: You can set a Path for a Ball joint by moving it with Offset and recording the position. Since a Ball joint with a Path setting can also be used as a normal Ball joint, you can create a movie in which the sphere bounces while rotating, if you rotate it using inverse kinematics.
Creating a Camera Path
Using the existing object from the previous page, you will learn how to set a Camera Path.
You will create a Camera and move it in a zigzag to follow the sphere that moves along its own Path while directing the camera to the center of the sphere changing angles.
When you set a Camera path, you can also choose from the two procedures (with the Auto Key checkbox on or off), although the setting for a Camera Path is a little different as follows:
With the Auto Key Checkbox Turned Off:
If an object is moving, drag the Sequence Cursor first to move the object and direct the Camera to the object, even if the Auto Key checkbox is turned off.
With the Auto Key Checkbox Turned On:
The setting is the same as previously specified.
Keep the above points in mind when making the setting.
1. Choose the Toolbox / Part tool / Camera. Click on the ruler, then drag from Point A in the Top view to create a Camera that faces the center of the sphere.
2. Choose the View menu / Camera to open the Camera window. From the upper-right Camera pulldown menu, choose Camera to change the display in the perspective view to that seen from the Camera.
Check that the Sequence checkbox is turned on.
With the Auto Key Checkbox Turned Off
Record the position of the created Camera as the first position.
1. Select the Camera in the Joint Selection box and Z key + click (Win) / option key + click (Mac) in the Sequence Key box to record the first position.
The first position of the Camera has been recorded.
Record the next position.
2. To make the Camera follow the sphere moving along the Path in a zigzag fashion, drag the Sequence Cursor to move the sphere along the Ball joint Path.
IMPORTANT: For the Camera Path setting, if an object is moving, drag the Sequence Cursor first to move the object and direct the Camera to the object, even if the Auto Key checkbox is turned off.
3. Select the Camera in the Joint Selection box and choose the Toolbox / Move tool / Offset.
Drag the Camera in the Top view, as shown in the figure below.
4. In the Camera window, adjust the Camera so that it faces the object while toggling the Eye and Target radio buttons.
Adjust the Camera so that it faces the center of the sphere
5. Z key + click (Win) / option key + click (Mac) in the Sequence Key box or on the Sequence Ruler to record the position.
The second position has been recorded.
Similarly, record the other positions by repeating the previous procedure, following the sequence (3, 3’, 3”, 4, 4’, 4”…) shown in the figures below.
6. To make the Camera follow the sphere moving along the Path in a zigzag fashion, drag the Sequence Cursor to move the sphere along the Ball joint Path.
7. Using the Offset function, move the Camera up to the position shown in the figure below.
Note: If you hold down the Ctrl key (Win) / option key (Mac) and chose the Toolbox / Move tool / Offset, you can perform the Offset function continuously without choosing Offset again. When you are finished, click the finish button in the Toolbox, or press the Enter key.
8. In the Camera window, adjust the Camera so that it faces the object while toggling the Eye and Target radio buttons.
9. Z key + click (Win) / option key + click (Mac) in the Sequence Key box or on the Sequence Ruler to record the position.
Repeat the above procedure for each position.
With the Auto Key Checkbox Turned On:
Record the position of the created Camera as the first position.
1. Since there is no change in the Camera joint value, a Sequence Key Point is not created at this stage. As in the case of the Auto Key checkbox turned off, select the Camera in the Joint Selection box and Z key + click (Win) / option key + click (Mac) in the Sequence Key box to record the first position.
The first position of the Camera has been recorded.
Record the next position.
2. Drag the Sequence Cursor to the frame at which the position will be recorded.
3. Select the Camera from the Joint Selection box and choose the Toolbox / Move tool / Offset.
Drag the Camera in the Top view, as shown in the figure above.
4. In the Camera window, adjust the Camera so that it faces the object while toggling the Eye and Target radio buttons.
Adjust the Camera so that it faces the center of the sphere
5. New Motion Points are automatically generated when moving the Camera using the Offset function, and updated when adjusting the direction the Camera faces.
Points are automatically generated because Auto Key is selected
The second position has been recorded.
Similarly, record the other positions by repeating the previous procedure, following the sequence (3, 3’, 3”, 4, 4’, 4”…) shown in the figures below.
6. Move the Sequence Cursor to the frame at which the position will be recorded.
7. Using the Offset function, move the Camera up to the position shown in the Figure window below.
Note: If you hold down the Ctrl key (Win) / option key (Mac) and chose the Toolbox / Move tool/ Offset, you can perform the Offset function continuously without choosing Offset again. When you are finished, click the finish button in the Toolbox, or press the Enter key.
8. In the Camera window, adjust the Camera so that it faces the object while toggling the Eye and Target radio buttons.
9. Each time you repeat the above procedure, Points are created at the frame to which you dragged the Sequence Cursor.
The Procedure is Common to Both Methods From Here On
You can make the Corner-on setting for the Camera Path points, as you did for the Ball joint.
1. Select the multiple Sequence Key Points shown in the figure below using the Ctrl key + click (Win) / }{ key + click (Mac) to set Corner-on for the Motion Points.
A corner is formed at each Corner-on Point on the Path, making a straight line.
Move the Sequence Cursor to frame 0 and start the preview.
You can modify the Path line directly.
2. Check that the Sequence checkbox and the Auto key checkbox are turned on, choose the Toolbox / Modify tool / Enter Modify Mode to enter the MODIFY mode.
3. In the Figure window, drag the control points to modify the Path line.
This is an extreme example in which the straight line is changed to a zigzag line
Note: If you drag the selected control point of the Camera, the Camera and its Path will be moved together. To prevent this, when you want to adjust the Path in the Figure window, move the Sequence Cursor to a frame at which no Motion Point exists, so as not to overlay the Camera on a control point of the Path, as you did for the Ball joint Path.
Check the motion in the preview.
4. Move the Sequence Key Points to adjust the speed.
Shortening an interval between Sequence Key Points makes the speed faster, while extending the interval makes the speed slower.
Check the motion in the preview.
Let’s create a movie file by rendering an animation based on the settings.
5. Choose the Rendering menu / Create Animation to open the Animation Settings dialog box.
In the Animation Settings dialog box, enter 0 in the “From” text box, 70 in the “To” text box. Leave all other values at the defaults.
The folder and file name, and the Compression Settings (that appear after pressing the OK button) can be specified as you like.
You have now completed setting a Camera Path.
6. You can also use the Eye or Target point of a Camera for a specified object.
Here we use the Target point for the Ball to make the Camera face the sphere.
To make this setting, select the target object (Ball) and click the Link button to the right of the Target radio button in the Camera window.
Now the Target point of the Camera will keep it always facing the Ball.
By clicking the Link button, it will change to the Unlink button. When you want to cancel the motion of the Camera, click the Unlink button.
Check the motion in the preview.
SmartKinematics
SmartKinematics is a feature designed to work together with Inverse Kinematics (IK) to provide precise control over the posing and animation of complex joints. Objects such as human figures, animals, or complex machinery often exhibit complex movement that is difficult to quickly and accurately represent by hand--and this is where SmartKinematics shows its strength.
Attribute Settings
Open the file “UG_18_smartkinematics01_ setup. shd” from ShadeExplorer. (For details on opening tutorial files like this one from ShadeExplorer, see “Opening Files from ShadeExplorer” on page 1).
If the Browser is not already visible, display it by selecting “Browser” from the “View” menu.
Open the SmartKinematics window by selecting “SmartKinematics” from the “View” menu.
Select the “Body” joint in the Browser, and then click the Root group’s Apply button in the SmartKinematics window. The Root attribute is assigned to the “Body” joint, and “Root(SmartKinematics)” is added to the “Body” name in the Browser. A joint with the Root attribute is called a Root Joint.
Use the Control (Mac) or Ctrl (Win) key to select both the “Left Ankle” and “Right Ankle” parts in the Browser. Then click the Goal group’s Apply button in the SmartKinematics window.
The Goal attribute is assigned to the left and right ankles, and “Goal(SmartKinematics)” is appended to both names in the Browser. A joint with the Goal attribute is called a Goal Joint.
Note: To assign the same attribute to multiple parts, simply select those parts in the Browser and click the appropriate Apply button in the SmartKinematics window.
With the “Body : Root(SmartKinematics)” joint selected in the Browser, choose “Offset” from the Move tool in the Toolbox, and click and drag the mouse around a bit in the Front or Side view of the Display window to see the results of the SmartKinematics attributes.
The movement of the left and right ankle parts is now constrained so that they continuously point toward their original positions (the positions at which you applied the Goal attribute).
From the “Edit” menu choose “Undo” to undo the Offset operation.
Now create a ball joint at the heel and toe positions for both the left and right feet of the robot. To create a ball joint, choose “Ball Joint” from the Part tool in the Toolbox, and click on the figure at the point where you want to create the ball joint. Repeat this for the other three positions.
In the Browser, move each of the ball joints to the appropriate position as shown in the figure below.
Using the Control (Mac) or Ctrl (Win) key, select all four ball joints underneath the “Left Ankle” and “Right Ankle” in the Browser, and in the SmartKinematics window click the Apply button in the End group. The End attribute is assigned to each of the ball joints, and “End(SmartKinematics)” is appended to the names of each of the ball joints in the Browser. A joint with the End attribute is called an End Joint.
With the “Body : Root(SmartKinematics)” part selected in the Browser, choose “Offset” from the Move tool and click and drag the mouse in the Display window.
The movement of the left and right ankles is now constrained such that the toe and heel points of each foot retain their positions relative to each other.
Undo the Offset operation by selecting “Undo” from the “Edit” menu.
In the Browser, select the “Ball Joint : End(SmartKinematics)” part for the toe that is child to the left ankle (i.e. within the “Left Ankle” part). Now choose “Offset” from the Move tool. When you click and drag in the Display window, the movement of the whole robot follows the movement of the left toe.
Deleting Joint Attributes
To remove SmartKinematics attributes from a joint to which attributes have been applied, simply select the joint in the Browser and click the “Delete attribute” button in the SmartKinematics window.
If you want to assign a new attribute to a joint, first delete the unwanted attribute from the joint as outlined above and then apply the new attribute.
Inverse Kinematics (IK) Advanced Settings
SmartKinematics allows you to adjust the IK movement in accordance with the desired effect.
Controlling Joint Constraints
SmartKinematics allows you to select the level of constraint placed on Goal joints. This constraint does not affect movement such as using the Offset tool to move the entire IK chain. The three levels of constraint are explained below.
Open the file “UG_18_smartkinematics02_ snap. shd” from ShadeExplorer. (For details on opening tutorial files like this one from ShadeExplorer, see “Opening Files from ShadeExplorer” on page 1).
Open the SmartKinematics window by choosing “SmartKinematics” from the “View” window. Also, open the Browser if it is not already displayed, and select “Rotator Left Knee.”
In the Inverse Kinematics group in the SmartKinematics window, check the box labeled “Enable.”
Select “Standard” in the Constraint of Selected Joints pull-down menu.
With the “Rotator Left Knee” joint selected in the Browser, choose “Left Leg 2” from the Move tool in the Toolbox to set the IK. Then try clicking and dragging the mouse a bit in the Display window.
A constraint is put on the ankle, restricting the toe and heel to minimal movement.
Undo the Transform operation by choosing “Undo” from the “Edit” menu.
Now select “Half” from the Constraint of Selected Joints pull-down menu.
With the “Rotator Left Knee” joint selected in the Browser, choose “Left Leg 2” from the Transform button to set the IK.
The knee and thigh move freely, but the foot is kept parallel to the ground. The heel and toe of the foot retain their original relative positions as they follow the leg.
Undo the Transform operation by choosing “Undo” from the “Edit” menu.
Finally, select “Free” from the Constraint of Selected Joints pull-down menu.
With the “Rotator Left Knee” joint selected in the Browser, choose “Left Leg 2” from the Transform button to set the IK.
The knee and thigh move freely, but the ankle and foot are fixed in position as they follow the leg.
Preserving the End Angle
When human or animal figures are walking, the end joint must move relative to its original position. In cases like these, you will need to specify how joints below the goal joint will move. Below we will compare the differences in movement between preserving and not preserving the end angle.
Open the file “UG_18_smartkinematics02_ snap.shd” from ShadeExplorer. (For details on opening tutorial files like this one from ShadeExplorer, see “Opening Files from ShadeExplorer” on page 1).
Open the SmartKinematics window and the Browser if they are not already open. In the Browser, select “Body : Root(SmartKinematics).”
Check the box for “Preserve End Angle” in the Inverse Kinematics group of the SmartKinematics window.
With the body part selected, choose “Offset” from the Move tool. When you click and drag the mouse in the Display window, the ankle joint and everything below the ankle maintain their original orientation, regardless of how the body is moved or rotated.
Important: The end angle can only be preserved if there are two or more end joints.
Select “Undo” from the “Edit” menu to undo the Offset operation.
In the Inverse Kinematics group within the SmartKinematics window, uncheck the “Preserve End Angle” checkbox.
With the “Body : Root(SmartKinematics)” part selected in the Browser, choose “Offset” or “Body” from the Move tool, and click and drag in the Display window. When the feet leave the ground, the ankle joint rotates so that the toe and heel point toward their original positions.
IK Snap
IK Snap allows you to set the end joint so that it snaps to the ground level when it is within a close range (you can specify the exact tolerance).
IK Snap is especially useful when creating walking animations in which you want to set the feet on the ground precisely and easily.
IK Snap can be used if the Inverse Kinematics “Enable” checkbox is off, or if the Inverse Kinematics “Enable” checkbox is on but the Constraint of Selected Joints pull-down menu is set to “Free.”
Open the file “UG_18_smartkinematics02_ snap. shd” from ShadeExplorer. (For details on opening tutorial files like this one from ShadeExplorer, see “Opening Files from ShadeExplorer” on page 1).
In the Browser, select either “Body : Root(SmartKinematics)” or a child part (a part lower in the hierarchy than “Body”).
In the SmartKinematics window, enable Inverse Kinematics by checking the “Enable” checkbox in the Inverse Kinematics group.
Enable IK Snap by checking the “Enable” checkbox in the IK Snap group in the SmartKinematics window.
With “Rotator Left Knee” selected in the Browser, choose “Left Leg 2” from the Move tool, and click and drag the mouse in the Display window. The end joints at the toe and heel of the foot are snapped to the level of the ground when they move within a half grid of the ground level.
Select “Undo” from the “Edit” menu to undo the Transform operation.
With “Left Ankle : Goal(SmartKinematics)” selected in the Browser, choose “Left Ankle” from the Move tool, and click and drag the mouse in the Display window.
Of the end joints at the toe and heel of the foot, the lower of the two end joints stays along the level of the ground. The knee and thigh move accordingly.
Cleanup
Animation between motion points can sometimes result in awkward movements, such as a foot seeming to slip across the ground. Unnatural movement occurring between motion points can be corrected with the Cleanup tool.
Open the file “UG_18_smartkinematics03_ cleanup. shd” from ShadeExplorer. (For details on opening tutorial files like this one from ShadeExplorer, see “ “).
Open the Browser and the SmartKinematics window if they are not currently displayed.
With the “Body : Root(SmartKinematics)” joint selected in the Browser, verify that the Cleanup “Enable” checkbox is checked in the SmartKinematics window.
Open the Motion window by choosing it from the “View” menu.
Preview the animation by clicking the Play button in the Motion window. You can see that there are some points at which the robot’s legs move faster or drop below the ground level.
Check the Cleanup “Enable” checkbox in the SmartKinematics window.
In the Motion window, select all the motion points.
In the SmartKinematics window, click the Cleanup “Calculate” button.
Click the Play button in the Motion window. The position of the feet is constrained, and the movement is now smooth.
However, you can also see that the robot is now not jumping correctly.
In the Motion window, select the tenth, eleventh, and twelfth motion points (frames 85 - 95), which correspond to the robot’s jump.
In the SmartKinematics window, click the Cleanup “Disable” button. This disables the Cleanup constraints on the feet for the duration of the jump.
Now when you click the Play button in the Motion window, the robot moves naturally.
AimConstraints
AimConstraints allow you to restrict, or constrain, the orientation of an object so that it always faces toward a target object. Using AimConstraints allows you to precisely control animation and posing of complexly jointed objects. Or, by assigning the AimConstraint target to the camera, you can create an animation in which an object is constantly facing the camera, for example. AimConstraints is available in Shade 9 standard and professional versions.
Targeting an Object
First you will need to assign the AimConstraint target to an object. Afterwards you can confirm that the object moves correctly relative to the target.
Creating the Target
Open “UG_18_aimconstraints.shd” from ShadeExplorer.
Display the Browser by choosing “Browser” from the “View” menu if it is not already visible.
Select “Turret” in the Browser.
From the Part tool in the Toolbox, choose “Aim Target.” The Create AimConstraints Target dialog box appears.
Verify that the box labeled “Create object out of IK end joint,” is NOT checked, and then click OK.
In the Display window, position the 3D cursor at the Note of the turret and click.
The AimConstraints target is assigned to the “Turret” object, and “AimConstraints” is appended to the object’s name in the Browser. Furthermore, a ball joint has been created below the turret part in the Browser. The name “Target : AimConstraints” is shown.
Select “Target : AimConstraints” in the Browser.
Select the Offset option from the Move tool in the Toolbox, and click and drag in the Display window to move the object. Because the “Turret : AimConstraints” joint is a Y axis rotator joint, it is best moved by dragging the mouse in the Top view. The turret moves in the direction you drag the mouse.
In the Browser, move the “Target : AimConstraints” part to outside the “Body : Root(SmartKinematics)” joint. The hierarchy should look like this:
Select the “Body : Root(SmartKinematics) joint.”
Choose “Offset” from the Move tool in the Toolbox, and click and drag the mouse in the Display window to move the “Body” joint. You can see that as the body moves, the turret stays pointing toward the target.
Open the Motion window by choosing “Motion” from the “View” menu.
Click the Play button in the Motion window to preview the animation. As the robot moves, the turret rotates to face the target.
Deleting the Target
The AimConstraints target is removed by deleting the target ball joint.
In the Browser, delete “Target : AimConstraints.”
AimConstraints is deleted from the robot, and the turret name in the Browser returns to “Turret.”
Assigning an AimConstraints Target in the Browser Hierarchy
Open “UG_18_aimconstraints.shd” from ShadeExplorer.
Display the Browser if it is not already visible.
Select the “Turret” joint in the Browser.
From the Part tool in the Toolbox, select “Aim Target.” The Create AimConstraints Target dialog box appears.
Check the “Create object out of IK end joint” checkbox and then click OK.
In the Display window, position the cursor over the Note of the turret and click.
The AimConstraints target is assigned to the “Turret” object, and “Aim Object : AimConstraints” is appended to the object’s name in the Browser. Furthermore, a ball joint has been created inside (i.e. child to) the turret part in the Browser. The name “End : AimConstraints” is listed. Finally, another ball joint has been created below (i.e. brother to) the turret part, called “Target : AimConstraints.”
In the Browser, move the “End : AimConstraints” part to within the “Cannon” joint, and move the “Target : AimConstraints” part to outside the “Body : Root(SmartKinematics) joint.
With “Target : AimConstraints” selected in the Browser, choose “Offset” from the Move tool and click and drag the mouse in the Display window. Try moving the mouse in both the Top view (to easily see the turret rotate) and the Front or Side views (to easily see the cannon move up and down).
Note: Clicking “Cont. Mode” in the Toolbox enters Continuous Mode, allowing you to perform an operation such as Offset multiple times without having to reselect the tool.
The turret and cannon follow the movement of the target.
Open the Motion window by selecting “Motion” from the “View” menu.
Click the Play button to preview the animation. Verify that the turret and cannon move to face the direction of the target.
Targeting a Camera
First you will need to set the AimConstraint target to a camera. Then you can confirm that the movement is executed correctly.
Whichever camera is currently selected in the Camera window will be set as the AimConstraint target.
Setting the Target
From the “File” menu select “New” to open a new scene.
Display the Browser if it is not already visible.
Choose “Rotator” from the Part tool in the Toolbox, and click in the Front view to create a Y-axis rotator joint.
With “Rotator” selected in the Browser, choose “Rectangle” from the Create tool in the Toolbox. Create the rectangle around the rotator in the Front view of the Display window, as shown below.
Verify that the rectangle (listed as “Closed line” in the Browser) is inside (child to) the rotator joint.
Now select the “Rotator” joint in the Browser.
From the Custom tool in the Toolbox, choose “AimConstraints Camera Attributes.” The AimConstraints Camera Attributes dialog box appears.
Check the “Apply” checkbox and click OK. In the Display window, a wireframe appears showing the direction of the camera. In the Browser, “Aim Camera : AimConstraints” has been appended to the “Rotator” joint.
In either the Display window or the Camera window, move the camera around, and then release the mouse button. The rectangle moves to face toward the camera.
Note: For details on moving the camera, refer to “Using the Camera” Chapter 1 of the User Guide.
Deleting the Camera Target
First select the “Rotator (Aim Camera) : AimConstraints” part in the Browser.
From the Custom tool, choose “AimConstraints Camera Attributes.” The AimConstraints Camera Attributes dialog box appears.
Uncheck the “Apply” checkbox and click OK. The Camera Target should be deleted, and the name of the rotator joint in the Browser returns to simply “Rotator.”
PathConstraints
PathConstraints provides additional power to Shade’s animation features and is used to animate objects smoothly along a path or set still objects to a specifically shaped path.
Animating Objects Along a Path
Animating a Train Along a Track
Creating the Train
To model a simple train, extrude a closed line object and then create a hierarchy structure with a ball joint. To illustrate how PathConstraints works a sample file is included ready to use.
1. Open ShadeExplorer by choosing ShadeExplorer from the View menu.
2. In ShadeExplorer select the Documentation- Sample tab and open “PM_PathConst01_rail.shd.” If you drag and drop the file into the Figure window from ShadeExplorer the objects in the scene will be placed inside a part. In this file an open line represents the path that the train will follow, a closed line represents the cross section of the track, and an extruded closed line represents the train car. The open line will be the path used for PathConstraints.
3. Choose Ball Joint from the Part tool in the Toolbox and click at the front end of the train to create a ball joint there. In this sample file, the ball joint should be located precisely at the origin of the scene, world coordinates 0, 0, 0.
4. In the Browser, move the extruded closed line inside the ball joint. This train car will be the first car.
5. With the Ball Joint part selected in the Browser, choose Copy > Translation from the Toolbox and create a copy of the train car behind the original. Do the copy operation four times so that the result is five train cars lined up in a row.
6. Now arrange the objects in the Browser so that the ball joints (and train cars) are nested within each other, as shown below. The last train car should be nested inside the fourth ball joint, which in turn should be nested within the third ball joint, and so on creating a hierarchy of ball joints.The train is now finished.
Creating the Track
To create the train track we will extrude the closed line object along the path of the open line. Since this is the same open line that will be used for PathConstraints, it will be easiest to set the starting point at exactly the same point as the ball joint of the first car. The starting point of the open line in this sample file is at the origin.
1. Select the open line and click the Memorize button in the Toolbox to memorize the object. If the Memorize button is hidden, click the black triangle next to Memory in the Toolbox to make it visible.
2. Select the closed line and choose Sweep (under Memory) in the Toolbox.
The track is extruded along the open line.
Using PathConstraints
PathConstaints allows you to control the path of a still or animated object.
1. In the Toolbox, choose Part > Path. A path joint is created.
2. Move the newly created path joint directly below the open line in the Browser.
3. Now move the entire train inside the path joint.
4. With the path joint selected in the Browser choose Object Info from the View menu. By moving the Path slider in the Object Info window the first train car moves along the path, with the rear cars following rigidly behind it.
5. With the path joint still selected in the Browser, choose Part > PathConstraints End in the Toolbox. The PathConstraints dialog appears.
6. The default settings are suitable for the purpose of illustrating PathConstraints here, so click OK to accept the settings. (For details about the PathConstraints dialog box, please see “PathConstraints - Reference” later in this chapter.) The PathConstraints attribute is now applied to the path joint. In the Browser this is displayed as “Path:PathConstraints”.
7. Select the joint of the last car of the train in the Browser.
8. In the Figure Window, click or drag the cursor at the rearmost edge of the last car. An End object (End: PathConstraints) is created below the joint selected in the Browser. End objects must be created behind the last ball joint. Note: When creating End objects, dragging the cursor in the Figure Window will change the size of the object but this size has no effect on its function.Note: The End object can be moved in the Figure window or moved in the Browser hierarchy after it is created.
9. In the Browser, select Path: PathConstraints and adjust the joint slider of the path joint in the Object Info window to move the train along the path.The movement of the train is constricted so that the centers of all the ball joints and the End object stay on top of the path. If the position of a joint or End object is off-center one or more of the train cars may face the wrong direction. In that case, enter Modify Mode and adjust the center of the joint or End object.
10. To record an animation of the train, open the Motion window and add keypoints along the timeline by moving the Path: PathConstraints slider. When finished setting up the timeline, render out the animation by selecting Create Animation from the Rendering menu.
Moving a Train Along a Banked Track
1. Open “PM_PathConst02_bank.shd” from the ShadeExplorer Documentation-Sample tab. If you drag and drop the file into the Figure window from ShadeExplorer the objects in the scene will be placed inside a Part.This file contains a train with PathConstraints and a banked track.
2. Moving the Path slider of the Path:PathConstraints part in the Object Info window will move the train along the track but the train keeps its vertical orientation, ignoring the bank.The “upper direction” in the PathConstraints dialog box must be adjusted in order to move the train along the bank. Create a copy of the original path and then create the “upper direction”.
3. With either the Path: PathConstraints joint or the End: PathConstraints object selected in the Browser, choose PathConstraints Attributes from the Custom tool in the Toolbox. The PathConstraints Attributes dialog box appears.
4. Verify that the “Use the upper direction path if it exists” checkbox is checked. If it is not checked, check it now.
5. Make a copy of the Open line that is directly above the path joint in the Browser, and move this copy above the original Open line.
6. Now edit the copied Open line in the Figure window. The angle between the position of this line and the position of the original line will be the bank of the track.
7. Moving the slider in the Object Info window of the Path joint causes the train to move along the track following the bank. If the angle of the train does not match the angle of the track, adjust the path while checking the angle.
Setting Objects to a Specific Path
Creating a Bicycle Chain
1. Open “PM_PathConst03_chain.shd” from the ShadeExplorer Documentation-Sample tab.
In this file there are link objects with two components that form the chain and a closed line which forms the path for the chain. Rotator joints are set for each piece of the chain. These rotator joints are all flat joints.
NoteS: Objects with many links, such as a bicycle chain, are easier to work with in the Browser if they are set to be flat joints. Select “Flat” from the drop down menu in the lower left corner of the Object Info window to make an object a flat joint. Flat joints share the same hierarchy level in the Browser with each other but are treated as if they were nested.
2. Select Path from the Part tool in the Toolbox. A Path joint is created in the Browser.
3. Move the Path joint to just below the Closed line in the Browser.
4. Now move the entire bicycle chain object (Rotator_A01 to Rotator_B32) inside the Path joint in the Browser.
5. With the Path joint selected in the Browser, choose PathConstraints End from the Part tool in the Toolbox. The PathConstraints dialog box appears.
6. The default settings are appropriate this time so click OK without modifying the settings. The PathConstraints attribute is applied to the Path joint and the PathConstraints named is appended to the part name in the Browser. (For details about the PathConstraints dialog box, please see “PathConstraints - Reference” later in this chapter.)
7. Select the last object in the bicycle chain (Rotator_B32).
8. In the Figure window click or drag at the point of the last link in the bicycle chain. An End object is created below the Rotator_B32 part selected in the Browser.
9. By moving the slider of the Path joint in the Object Info window the chain moves along the path.Note: If the path is a closed line object it will form a loop even if the joint value is 0. However, zooming in to the start of the chain in the Figure window will reveal that the chain is not quite long enough. Several links must be added to complete the chain.
10. Select all the rotator joints inside the Path joint in the Browser and then select Reset All Joints from the Move tool in the Toolbox. The chain returns to its original position.
11. Select Rotator_A32 and Rotator_B32 and choose Translate from the Copy tool.
12. Double-click the newly created parts to change their names to Rotator_A33 and Rotator_B33.
13. Now move the new links appropriately in both the Figure window and the Browser.
In the Figure window, move the new links to the end of the chain. In the Browser, move them below the Rotator_A32 and Rotator_B32 parts.
14. By opening the Rotator_B33 part in the Browser you will see an End part. This object is not needed, so it can be deleted.Important: If an object containing an End object is copied, a new End object will be created along with the new object; however this new End object has no effect on the PathConstraints. The correct End object is named “End: PathConstraints”.
15. Move the PathConstraints End object to the Rotator_B33 link in the Figure window, and inside the Rotator_B33 object in the Browser.
16. Open the Object Info window for the Path joint again and watch the chain move along the path as you move the slider back and forth. This time, zooming in to the start of the chain shows that the chain is the perfect length.If you add links to the chain and the length is not quite right, adjust the length of either the path or the links themselves.
Note: When animating bicycles or similar situations when the chain must rotate continually, modifying the range of joint values used by the slider makes it easy to adjust the acceleration or deceleration. Click the joint slider while holding the Ctrl (Win) or Control (Mac) key to open the Joint Advanced Settings. Set the maximum value to be the number of loops you wish the chain to make and the slider will then show multiple revolutions.
PathConstraints Reference
PathConstraints Attribute Settings
When applying PathConstraints to a path joint, choose PathConstraints_end_creator from the Part tool in the Toolbox with the path joint selected in the Browser. Adjust the settings in the PathConstraints dialog box, click OK, and then select the last joint (ball joint or rotator joint) in the hierarchy of the path joint to create a PathConstraints End object.
Adjusting PathConstraints Attributes
To modify the PathConstraints attributes of a path joint choose PathConstraints Attributes from the Custom tool in the Toolbox with the PathConstraints part or End part selected in the Browser, and adjust the settings in the PathConstraints Attributes dialog box.
Deleting PathConstraints Attributes
To remove PathConstraints from a path joint, delete the corresponding PathConstraints End object.
The PathConstraints Dialog
The PathConstraints dialog is where the PathConstraints attributes can be modified.
Upper direction Pull-Down Menu
Specify the X, Y or Z axis for the upper direction of the PathConstraints object. If the axis specified here and the direction of the path line object overlap, the object may face the incorrect direction. This setting is only valid for ball joints and rotator joints that are parallel to the path line object.
Auto Roll: The PathConstraints object will not control the upper direction. Even if the path overlaps with the X, Y or Z axis direction the object will face correctly, but the Roll rotator can be added to fit the path or motion.
Use the Upper Direction Path If it Exists Checkbox
If there are two line objects immediately above the path joint in the Browser hierarchy the first line will be used to specify the angle of the path. If Auto Roll is selected in the Upper Direction drop down menu this line will not be used to specify the angle.
Ignore Limiter of the Joints Checkbox
When checked, the range limiter of the PathConstraints rotator joint will be ignored. To turn the limiter on or off for individual rotator joints, leave this checkbox off and in the Object Info window check the Range checkbox for individual rotator joints. |
