Samples image colour at a specified pixel location.
Container for user-defined plugs. Nodes should never make their own plugs here, so users are free to do as they wish.
The image to be sampled.
The names of the four channels to be sampled.
The coordinates of the pixel to sample. These can have fractional values and bilinear interpolation will be used to interpolate between adjacent pixels.
Note though that the coordinates at pixel centres are not integers. For example, the centre of the bottom left pixel of an image is at 0.5, 0.5.
The sampled colour.