Building block shaders

This paper describes an implementation of Cook's "shade trees" in which shaders are described as networks of modules, building blocks, whose connections can be defined interactively.The high level interface to the shaders is a graphical editor which permits users to construct complex shaders by connecting shading elements in a network, in effect a graphical shading language. A low level interface to the shaders is also provided. In the low level interface, shading elements are programmed in a standard programming language and compiled into modules which can linked either at run time or compile time.Each link in the shading network represents a subroutine call. In essence, execution of the network is analogous to the execution of an interpreted language.