Clamp 0 Colour
The Clamp 0 family of nodes allow you to clamp, or restrict, the values of the colour or scalar coming into the Input so they are always at least 0. If the value is less than 0 it will become 0. All other values remain unchanged. This is useful for ensuring there are no negative numbers passing through a node network.
The clamping is done component-wise for colours. Here is an example using a colour with the following values:
Input.red is -1
Input.green is 0.5
Input.blue is 2
After clamping the colour will have these values:
Input.red becomes 0 (-1 was less than 0, so it becomes 0)
Input.green remains 0.5 (0.5 is greater than 0, so it's unchanged)
Input.blue remains 2 (2 is greater than 0, so it's unchanged)
In the example below, an EXR image containing vector data is assigned to the Main Input of the Clamp 0 Colour node. Visually, the green pixels represent data above a value of 0 in the Y axis, whereas the magenta pixels indicate a blend of positive and negative values lying on the X and Z axis. When enabled, the Clamp 0 Colour node outputs all negative values as 0.
- Name: This setting allows you to apply a descriptive name to the node, which can be helpful when using multiple Clamp 0 Colour nodes in a project.
- Enable: When checked, the node is active and the negative Main Input values below 0 become 0. When unchecked, the Main Input value is passed through the node.
A scalar is a single number. 1, 200.45, -45, -0.2 are all examples of scalar values.
A vector is a set of three scalars, normally representing X, Y and Z coordinates. It also commonly represents rotation, where the values are pitch, heading and bank.
A single object or device in the node network which generates or modifies data and may accept input data or create output data or both, depending on its function. Nodes usually have their own settings which control the data they create or how they modify data passing through them. Nodes are connected together in a network to perform work in a network-based user interface. In Terragen 2 nodes are connected together to describe a scene.