LADDER, a sketching language for user interface developers

Paper

Hammond, Tracy, and Randall Davis. "LADDER, a sketching language for user interface developers." Computers & Graphics 29.4 (2005): 518-532.

Publication Link: http://www.sciencedirect.com/science/article/pii/S0097849305000865

Summary

The paper gives an overview of the implementation of a sketch recognition designer development tool. LADDER is described as a simple language that can allow non-developer designers to easily create a sketch recognition interface for a given domain. The major points in the LADDER implementation are generally how to define a shape (using a combination of constraints) and shape recognition, which applies a bottom-up approach. The recognition approach in LADDER allows domain specific shape recognition by defining a per domain collection of Jess-rules. 

Discussion

Pros

The tool appears to be a very useful attempt to simplify the sketch recognition interface design.

Cons.

Although the work sounds quite novel and very useful if implemented correctly, i'm concerned about its effectiveness because of its generic nature. The authors do provide some base level domain descriptors that may help with this and other challenges, but it still feels like a complicated solution.