1. Introduction

Synthetic resources are a mechanism included in Motif that allows a developer to modify resource values as collected by or assigned to the Xt resource mechanism. That is, if a user should want to find the value of an Xt resource, but M*TIF would rather that the user not see the true value, the synthetic resource mechanism allows the M*TIF developer to ``fake out'' the Intrinsics, and replace the true instance variable values with modified values. Alternatively, the toolkit may prefer to transform a user specified value into something more palatable by the toolkit.

The more common usage of synthetic resources is to support resolution independence (see figure ). However, the toolkit developers also realized that the mechanism provided a way to protect ``delicate'' resources. For example, those that it would be dangerous for the user to change, or those that would upset the toolkit if they were unexpectedly modified.

Figure: Synthetic resources provide for data conversion as well as information hiding.

The import and export direction is seen from M*TIF's point of view. A user specified resource value is imported into some widget's instance variable. Au contraire, M*TIF exports a resource value whenever the user and/or application asks for a resource's value by calling Xt[Va]GetValues().