Basic Prop mocap in Motionbuilder

Bringing in Files:

a. File/Open or Merge the .fbx file that was recorded during capture session with Blade 2 or exported from Blade.

Motionbuilder can import motion files of the following formats: *.fbx;*.bvh;*.htr;*.trc;*.asf;*.amc;*.c3d;

b. If during the capture session your takes were saved as separate files you can continue Merging them into one file to only have to create one visualization setup.

BASIC WORKFLOW= Correct motion with Filters-->Edit Motion with Animation Layers-->Export or Save Motion Clips--> Use Story Tool to make longer sequnces or loops

Correcting Motion

Parent a primitive to your prop (try a cube) in order to clearly see rotations. Examine the appearance of movement from the distance you expect to see it in your project. Look for sudden general jitter and rotation flips.

1. Select a bone. In FCurve Editor select Translation and Rotation channels.

2.To eliminate jitter: in Filters (near Asset Browser) pick and run Peak removal filter. Then with the same properties selected try several iterations of Butterworth filter for added smoothing (try values 7Hz and higher). These filters are great for getting rid of fine jitter, but if you like to smooth the motion (ie too much "handheld" camera movement) you can use lower Butterworth filter values (ie 2) or Smooth filter. This will average all values, vs higher frequency Butterworth that will leave the min and max values intact while averaging the small variations. Smooth Filter does overall smoothing so use it carefully to avoid overly smooth floating quality of motion.

Use Gimbal or Unroll Filter to fix gimbal lock compensation that causes abrupt shifts in the rotation curves (ie from -180 to 180 degrees)

3. Visually examine motion for problems, such as shaking or flipping. Try deleting keys in those areas. In some cases Gimbal Lock is not possible to resolve manually. At this point you have three options:

a. Select Rotation parameters in the FCurves window. In Filters run Gimbal Killer.

b. Animate over the problem area using Animation Layer (Override Mode).

c. Cut out the problematic area by cutting action around it into clips and blend them together in the Story Editor.

Editing Motion with Animation Layers

You can choose to add or alter to your captured motion trajectories by keying additional motion (ie camera zoom or offset) using animation layers. Additive Layer animation alters the original motion and Override Layer animation replaces it.

1. Working with an Additive Layer: in Animation Layers Tab create a new layer. By default it's additive. Reposition your object to modify its trajectory and key the position as many times as necessary. Create Zero keys at the beginning and end of the time where you want your object's motion to look different from the original.

2. Working with an Override Layer: create a new animation layer, right-click and pick Layer Mode/Override. Key the frame where you want to animate the beginning of the different movement. At the same time key the Override Layer weight at 100 using the slider below the layer. Step to one frame earlier and key the weight at 0. You can also animate the Override Layer weight over longer periods of time allowing the original motion to blend with the override. If you want the object to return to the original trajectory you must animate the layer weight to change from 100 back to 0.

DO NOT SWITCH THE LAYER FROM ADDITIVE TO OVERRIDE AFTER ANIMATING IN IT.

Adding Simple Scene Elements (good documentation in HELP menu):

In Asset Browser you can find a number of simple elements for visualizing motion. You can also import models with textures and animation from Maya or Max either by exporting and merging them as FBX files or using the "Send to" feature.

Cameras:

Drag and drop a camera into the scene. In Navigator find Center of Interest node and delete if desired. Alternatively parent it to an object or animate it to control orientation of the camera.
Doubleclicking Camera in Navigator gives you access to Camera Properties, such as Background color, Angle of View, Front and Back clipping planes.

Materials:

From Elements/Shading Elements LMB drag a Material onto an object, then in Navigator find and double click it. Adjust properties like Emmissive, Diffuse and Ambient to achieve desired color and sensitivity to light.

To add an image based texture, drag Texture node from Shading Elements and drop it onto the object in the scene or material in the navigator. Connect as "diffuse". In Navigator double click the newly assigned texture, look for drop down menu "Media". Select New Media and find the desired image file. Experiment with Texture Mapping Method to get the right look. If your model has UVs pick UV, otherwise select a method that mimics the shape of your object.

Shaders:

To display transparent areas of the texture file you need to assign a Lighted or Flat shader. Drag either one from the Shader area and drop it onto the object. Pick Replace All or Replace by Type in the drop down menu. In the Shader settings in Navigator pick Accurate Transparency.

Physical Properties

Rigid bodies and Joint property.