Programming on Macintosh

1. Introduction

2. C Compiler for Macintosh

3. C Library for Psychophysics

1. Introduction

• Hardware for Visual Psychophysics in Shimojo Lab
• Indigo and O2 (SGI)
• VSG on Gateway2000 (Cambridge Reserach Systems)
• AMIGA (Commodore, AMIGA International)
• Macintosh (Apple)
• Advantage of Macintosh
• Cheap (vs. SGI, VSG)
• Easy extension (vs. SGI)
• Low level video control (vs. SGI)
• High spatial and temporal resolution (vs. AMIGA)
• Disadvantage of Macintosh
• Poor 3D graphics environment
• Unstable system software
• Future of Apple Inc.
• Software Environment for Visual Experiment on Macintosh
• Commercial software: e.g. Director
• Softwares developed by reserchers: e.g. Maclab, MacProbe, MacStim, PsyScope, RSVP, etc.
• Programming languages like C and MATLAB: see below

2. C Compiler for Macintosh

• Symantec C++ (Symantec)
• Think Project Manager: for 68K code
• Symantec Project Manager: for PowerPC code
• Metroworks Codewarrior (Metroworks)
• for both 68K and PowerPC codes
• supports also Java and Pascal
• How to make a project file: demo

3. C Library for Psychophysics

• Vision Shell (Comtois & Cavanagh at Harvard Vision Lab, MICRO M-L Inc.)
• Commercial product (about $500)
• Functions for accurate video control (synchronization of program with monitor)
• Functions for manipulation of stimulus parameters via GUI
• Rich drawing functions
• Source codes are not provided; object library only for Think C (68K code)
• Sample Code by Y. Kamitani

4StrokeAppMotion.c
• VideoToolbox (Pelli at NYU)
• Free
• Functions for accurate video control (synchronization of program with monitor)
• Rich statistical functions
• Source codes are provides; runs with both Metroworks and Symantec (both PPC and 68K)
• Messy collection of codes; hard to read and learn the codes

 

4. Psychophysics on MATLAB

• MATLAB (Mathworks)
• More intuitive and shorter code
• High-level functions
• No need for declaration of variables
• Matrix-based operation reduces the number of for-loops
• However, slower and less flexible than C, especially in graphics
• MEX file
• C functions can be converted into "MEX" files, which can be called from MATLAB
• MEX files are compiled codes, so fast to be executed
• Psychophysics Toolbox (Brainard & Pelli)
• Collection of functions in MEX (M) files converted from VideoToolbox
• Free
• Same graphical capability as VideoToolbox
• Easier code than VideoToolbox
• No GUI provided
• Poor drawing functions
• Sample code using PsychophysicsToolbox, by Y. Kamitani

LineMotion.m