# \#tip

**URL:** https://psychtoolbox.discourse.group/tag/tip/3.md

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## [How to test your PTB code automatically using Github](https://psychtoolbox.discourse.group/t/how-to-test-your-ptb-code-automatically-using-github/5822)

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**Author:** [@Ian-Max-Andolina](https://psychtoolbox.discourse.group/u/Ian-Max-Andolina)\
**Replies:** 0\
**Last updated:** [November 9, 2026, 2:09am UTC](https://psychtoolbox.discourse.group/t/how-to-test-your-ptb-code-automatically-using-github/5822 "2026-11-09T02:09:53Z")

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Automated tests are a great way to make sure your MATLAB / PTB code doesn’t break when you make changes. And if you use Github to version your code, it can run MATLAB automatically every time (continuous integration, CI)…

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## [PSA: Free book 'Matlab for the Behavioral Sciences'](https://psychtoolbox.discourse.group/t/psa-free-book-matlab-for-the-behavioral-sciences/5564)

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**Author:** [@mariokleiner](https://psychtoolbox.discourse.group/u/mariokleiner)\
**Replies:** 0\
**Last updated:** [November 20, 2024, 8:45am UTC](https://psychtoolbox.discourse.group/t/psa-free-book-matlab-for-the-behavioral-sciences/5564 "2024-11-20T08:45:37Z")

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This came through cvnet yesterday, maybe useful to some? Ione Fine and Geoff Boynton have put up a free Live Code (.mlx) format version of their book ‘Matlab for the Behavioral Sciences’ on Github for everyone to have a…

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## [Eye tracking in fMRI without eye tracker.](https://psychtoolbox.discourse.group/t/eye-tracking-in-fmri-without-eye-tracker/3536)

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**Author:** [@mariokleiner](https://psychtoolbox.discourse.group/u/mariokleiner)\
**Replies:** 0\
**Last updated:** [November 26, 2020, 1:13am UTC](https://psychtoolbox.discourse.group/t/eye-tracking-in-fmri-without-eye-tracker/3536 "2020-11-26T01:13:28Z")

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I stumbled over this VSS abstract from this year, by a former colleague of mine, which sounds somewhat nifty if it roughly works as advertised. Eye tracking in the scanner without eye tracker by using brain activity from…

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## [Learning to Write Procedural Shaders](https://psychtoolbox.discourse.group/t/learning-to-write-procedural-shaders/3089)

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**Author:** [@Ian-Max-Andolina](https://psychtoolbox.discourse.group/u/Ian-Max-Andolina)\
**Replies:** 1\
**Last updated:** [March 4, 2020, 6:15pm UTC](https://psychtoolbox.discourse.group/t/learning-to-write-procedural-shaders/3089 "2020-03-04T18:15:17Z")

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In OpenGL, there is a system that allows for very fast drawing of 2D and 3D graphics, using a mini language that runs on the GPU called OpenGL Shading Language (GLSL). IN PTB, these are the Procedural stimuli, as seen in…

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## [Playing Transparent Videos via PTB](https://psychtoolbox.discourse.group/t/playing-transparent-videos-via-ptb/3060)

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**Author:** [@Ian-Max-Andolina](https://psychtoolbox.discourse.group/u/Ian-Max-Andolina)\
**Replies:** 0\
**Last updated:** [February 18, 2020, 8:28am UTC](https://psychtoolbox.discourse.group/t/playing-transparent-videos-via-ptb/3060 "2020-02-18T08:28:59Z")

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Note: thanks to @mariokleiner who found this solution. Normal video file formats do not support transparency, however the advantages of transparency in a video would be that you could “composite” the object against a dy…