1. In a computing environment comprising a computer processor, memory, and an output device, a method for facilitating the layout and composition of graphics to be output to the output device, the method comprising: receiving declarative input for composing a layout composition, the declarative input comprising node identifications and layout directives and wherein the layout directives indicate layout relationships associating nodes within a layout composition; and in response to receiving the declarative input, interpreting the declarative input; and producing a layout composition in accordance with the declarative input for output to the output device.