2017

Table Of Contents
Lasso Fit field Displays the number of points in the segments of the spline that are drawn freehand. Use a
lower number to simplify the curve by removing vertices and tangents, resulting in a smoother curve.
Editable.
X Vertex field Displays the position of the selected vertices on the X axis. Editable.
Y Vertex field Displays the position of the selected vertices on the Y axis. Editable.
Z Vertex field Displays the position of the selected vertices on the Z axis. Editable.
Auto Tangents button Enable to position a tangent for each vertex set, to create a smooth curve between
the vertices. When enabled, it is possible to create a spline with both straight and curved segments.
When Auto Tangents is disabled, the tangents are positioned under the vertex, resulting in straight lines
between vertices. When you draw freehand segments in a spline with Auto Tangents off, vertices are added
with broken tangents, allowing the spline to follow your cursor movement.
Auto Adjust button Enable to automatically adjust the tangent handles of the two adjacent vertices when
moving vertices, to create smooth curves between the vertices.
Changing Spline Display Properties
You can change spline display properties in the Display tab. For example, you can change the colour of
tangents on the splines you draw. This is useful to better contrast the splines tangents from the clip so that
they are easier to work with.
Normals button Enable to display normals along the 3D path.
Normals colour pot Displays the normals colour. Editable.
Spacing field Displays the space between the displayed normals, in pixels. Also used to calculate the position
of the object on the path. A lower value may result in better positioning and smoother movement of the
object, but rendering may be slower. Editable.
Scale field Displays the scale of the displayed normals, in pixels. Editable.
Spline colour pot Displays the colour for the display of splines. Editable.
Tangents colour pot Displays the colour for the display of tangents. Editable.
Positioning Objects on the Path
Use the Position On Path settings in the 3D Path or Banking tabs to offset the position of attached objects
along the path and beyond. For open paths, if you offset past the first or last points on the path, the position
is extrapolated accordingly. For closed paths, if you offset past the first or last points on the path, the attached
object continues on the path with a tangent interpolated from the first and last normals.
614 | Chapter 15 Compositing in 3D Space with Action