Millisecond timing on PCs and Macs

A real-time, object-oriented solution for displaying stimuli on Windows 95/ 98, MacOS and Linux platforms is presented. The program, written in C++, ut ilizes a special-purpose window class (GLWindow), OpenGL, and 32-bit graphi cs acceleration; it avoids display timing uncertainty by substituting the n ew window class for the default window code for each system. We report the outcome of tests for real-time capability across PC and Mac platforms runni ng a variety of operating systems. The test program, which can be used as a shell for programming real-time experiments and testing specific processor s, is available at http://www.cs.dal.ca/similar to macinnwj. We propose to provide researchers with a sense of the usefulness of our program, highligh t the ability of many multitasking environments to achieve real time, as we ll as caution users about systems that may not achieve real time. even unde r optimal conditions.