File-based Content With Abstracts in Rails 3

For www.defiant.dk I was looking for a simple way to post my articles, projects and robots in a Rails 3-based app. I wanted to be able to edit the information using .html.erb using the existing layout and styling of www.defiant.dk. I ended up with a quick and easy design introducing a special content controller where partials play the role of abstracts. In this article I will show you the setup along with some considerations about where to go from here.

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Rasterizing Line Segments (Midpoint Line Algorithm)

The midpoint line algorithm for rasterizing lines on a grid is a well-known and fast algorithm. At the core of the algorithm lies the check for on which side of the midpoint between two pixel candidates the line lies. In this article I will develop the algorithm from the definition of a line as a point and a normal vector.

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CadSoft EAGLE: Creating a New Library Component

When you're using CadSoft EAGLE for designing electronic circuit boards, sometimes you're not able to find a specific component that you're planning to implement in your design in the available component libraries. If you're lucky you'll find that someone else has created the component and shared his work online but if you're out of luck you'll have to do the work yourself.

This article uses an example component and its datasheet and shows you how to create your own schematic components along with PCB footprints and how to connect those in order to get the correct wiring on your PCB. The component in the example is the IRF7309 dual P+N-channel MOSFET which is an SMD component in an SO8 package.

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