Tomas Laurenzo on #art and Tom Ritchford on #Git
Posted on June 11th, 2015
06/10/2015 @Thoughtworks, 99 Madison Ave, 15th floor, New York
The two speakers talked about the two aspects of this meetup: art and technology.
In the first presentation, #TomasLaurenzo (@SCM CityU Hong Kong) talked about his art: visual, politically motivated and whimsical. Using his education as an engineer, his art makes use of technology to create interactive displays. Installations he described include
- “Poem race” compares classic writers by coding a selection of their writings in Morse code. The dots and dashes control motors that that vibrate a ramp. The first item down the ramp indicates a winning author.
- Viewers interact with a Kinect which controls colors illuminating a cluster of balloons. The color changes based on sounds from music and people in the audience and inputs from smart phones.
- “Nadia” is a remembrance of the disappearances in Latin America. The viewer moves a physical lighter set to control how the image is “burned”
- “two systems” The viewer turns two knobs that control a “fire” which shows pictures of an image being burned.
- Wearable cinema done in conjunction with Alba, a designer (alba.uy), in which materials move and react to heart beats.
- A musical instrument controlled by the movement of your head.
- Actuators to deform the shape of a rectangular canvas on which an image is projected
- The empathy extension which highlights the differences in press coverage between terrorist acts in Kenya and in France. He changes “Kenya” for “France” when you search for “France” on Google.
In the second presentation, #TomRitchford gave a brief summary of Github along with a history of version control/change management software systems.
Source Code Control Systems (SCCS) were the developed in the 1970’s to create a central repository holding the official version of the software source code.
Later a quick way was developed to determine if your code matches that of the central repository: a hash code which is a compact fingerprint identifier (the SHA-1 hash function is 40 bytes long) quickly shows that two version of the code are the same or different (the delta).
When Linux was being created, there are thousands working on the system, so methods were needed to identify which branches were modified. Git was developed to organize the project. Git hash codes the entire project and the subparts within the project. Development proceeds along branches which are a sequence of commits each with its own hash. In this way, program changes by individuals are a sequence of hash codes. Functions include
- Push and pull only works on ancestors to descendents.
- You can cherry pick to get changes which are not from the ancestor.
- Rebasing – pull the series of changes and plant them on top of another series of changes.