There are a number of Data Types in Shader Graph. Each Port on a Node has an associated Data Type that defines what edges can be connected to it. The Data Types have colors for usability, these colors are applied to ports and edges of that Data Type.
|Vector 1||Light Blue||A Vector 1 or scalar value|
|Vector 2||Green||A Vector 2 value|
|Vector 3||Yellow||A Vector 3 value|
|Vector 4||Pink||A Vector 4 value|
|Dynamic Vector||Light Blue||See Dynamic Data Types below|
|Matrix 2||Blue||A Matrix 2x2 value|
|Matrix 3||Blue||A Matrix 3x3 value|
|Matrix 4||Blue||A Matrix 4x4 value|
|Dynamic Matrix||Blue||See Dynamic Data Types below|
|Dynamic||Blue||See Dynamic Data Types below|
|Boolean||Purple||A Boolean value. Defined as a float in the generated shader|
|Texture 2D||Red||A Texture 2D asset|
|Texture 2D Array||Red||A Texture 2D Array asset|
|Texture 3D||Red||A Texture 3D asset|
|Cubemap||Red||A Cubemap asset|
|Gradient||Grey||A Gradient value. Defined as a struct in the generated shader|
|SamplerState||Grey||A state used for sampling a texture|
All Vector types can be promoted or truncated to match any Vector type Port. This behaviour occurs only when the Port in question is not of type Dynamic Vector. When truncating, excess channels are simply removed. When promoting, the extra required channels are filled by default values. These values values are (0, 0, 0, 1).
Dynamic Data Types
Some Data Types are dynamic. This means a port using these Data Types can change their underlying Concrete Data Type based on what Data Type is connected to it. By default, Nodes using dynamic Data Types can only have one Concrete Data Type, meaning that once a connected edge has applied its Data Type to that port, all other Dynamic Data Type slots of that Node will apply the same Data Type.
One notable exception to this is the Multiply Node which allows both Dynamic Matrix and Vector types.
The Dynamic Vector type allows connected edges of any Vector type. All connected edges are automatically truncated to the type with the lowest dimension, unless the lowest dimension is 1, in which case the Vector 1 is promoted.
The Dynamic Matrix type allows connected edges of any Matrix type. All connected edges are automatically truncated to the type with the lowest dimension.
The Dynamic type is a special case. Nodes that support it must define how it is validated. In the case of the Multiply Node, it allows connections of any Vector or Matrix type, ensuring the correct multiplication is applied depending on the mix of Data Types.