ValueNode

A ValueNode is a value that changes over time.

An example of a ValueNode would be:

"3.4, for ever"

A more complex example: "3.4 at the beginning of the animation,

move smoothly up to 7.6 at time = 10 seconds,
then jump instantly to 2.0
and stay there until the end of time"

These are both descriptions of a value (in this case a real number) and how it changes (or doesn't!) over time.

ValueNodes are the things we see as the value for every parameter of every layer. The waypoints visible in the timetrack dialog are also part of the ValueNode - waypoints are how ValueNodes work out what value to be at each point in time.

Types

Each ValueNode (and hence each Parameter in Synfig has one of 13 types:

• Bool -- a boolean value; true or false. Represented in Studio as a checkbox
• Integer -- an integer value; a whole number. -3 or 0 or 2 are examples.
• Real -- a real number]. -3.0, 0.0, 2.0 and 3.1415 are examples.
• Angle -- a real number that is interpreted as an angle
• Time -- a time, displayed in days, hours, minutes, seconds and frames
• Vector -- a 2d vector. usually represented as two Reals representing X and Y values
• Color -- a color. Usually represented as Red/Green/Blue/Alpha values
• Segment -- a single bezier curve segment. Defined by 4 Vectors, representing 2 Vertices and 2 Tangents
• BLinePoint -- a point in a BLine. Defined by 6 parameters (a Vector defining its location, a Real defining its width, another Real defining its origin, a Bool defining whether its tangents are split or not, and two Vectors defining the direction of its tangents (only the first of which is used if the tangents aren't split)
• List -- A list. For example, an outline's Vertices parameter is simply a list of BLinePoint valuenodes.
• Canvas -- A collection of layers. When you encapsulate layers, you're creating a new inline canvas. The encapsulation layer has a parameter called 'Canvas' with type 'Canvas' and its value is the group of layers you've encapsulated.
• String -- a string of characters, for example "Hello Mum!"
• Gradient -- a range of colors (a mapping from a real parameter to a color). Can be defined in many ways, but is usually editing using the gradient editor.