PHP & More

A technical blog about programming in PHP and about technology in general: programming, workarounds and troubleshooting

The Bézier curve is a popular way to draw curves in graphic editors such as GIMP and Inkscape. A curve of degree n is defined using n+1 points, where the first and last are the start and end points of the curve, respectively, and the rest are control points. For example: The curve in the …

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How do you declare a static variable in a JavaScript function? Not with the word “static“. In JavaScript “function” is a variable type similar to “object“. The difference is that the reference to a function inside itself is not this but arguments.callee. An example of using arguments.callee is the following function that returns itself: function …

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Browsers supporting HTML5 allow you to draw on the browser’s screen without preparing an image file before. Drawing on a canvas is done using the wonderful Javascript language. If you want to draw a 2-dimensional image on canvas element ‘cnv’, get the drawing context using: var ctx = cnv.getContext(“2d”) And use that context to draw …

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WebSocket is an internet protocol that allow full-duplex communication between a client and a TCP/HTTP server. This means that data can be passed in both directions simultaneously. Unlike HTTP, in WebSocket protocol, the client doesn’t have to send a request in order to get responses. Incoming messages are handled by event handlers. HTML5 supports the …

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cURL is a tool used for browsing the web from the shell or command-line. It supports many internet protocols, such as HTTP, FTM, POP3, IMAP, SMTP and more. See the full list here. With libcurl installed in your system and the C API, you can browse using a C program. You can also install the …

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CSS3 is the newest CSS standard, and is supported by all modern browsers. Among the new style properties supported in CSS3, there are animation properties. Those properties allows you to animate HTML elements without the need of Javascript. CSS3 allows more animation options than those done by the non-standard yet supported marquee tags. It also …

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When you start Processing, you get an editor with a sketch name. You will probably want another name for your program, a name that means something. So, to change the name generated by the tool, you choose file->save as. Choose a name, and the tool will create a folder with that name, and a file …

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