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Added Videogame Design Seminar material (Italian).

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Flickering 2D transform elements in Chrome: a simple fix

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This quick post is to point out a fix to an issue I had to deal with a few weeks ago and was caused by a Chrome update. Components with absolute positioning and a 2D CSS transform started flickering when placed inside a scrollable component. A brief search online revealed several people with similar problems, but the suggested fixes were all very different. I tested several of them (including obvious changes to the z order) before finding the one that actually did the trick. What eventually worked for me was adding an empty 3D transform to the same elements with 2D transforms: transform:translate3d(0,0,0); I guess the reason why this works is that it forces elements to be drawn via a different rendering / compositing path than standard 2D elements.
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glVertexAttribPointer and double precision buffers

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This post will hopefully help people avoid a mistake that cost me several hours of debugging. In one of my projects I have been working with OpenGL 4 double precision vertex buffers. As the buffer data was passed to the shader as a generic attribute, I have been using  glVertexAttribPointer  to specify the attribute location in the data stream. This worked fine with floating point data. When I needed to switch to double precision, I checked the glVertexAttribPointer specification: this function accepts GL_DOUBLE as an input type: therefore, I assumed that change was all I needed to pass double precision data to my shader. I noticed two other version of the attrib pointer function existed ( glVertexAttribIPointer and  glVertexAttribLPointer ) but I thought they were just legacy functions or alternatives to using glVertexAttribPointer with GL_DOUBLE or GL_INT type specifiers. Things did not work as I expected. trying to pass double precision data to the shader cau...
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