Posts by Andrew Kallmeyer


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Derivation of the Orthographic Projection Matrix

The orthographic projection matrix takes a rectangular prism with corners at (l, t, -n) and (r, b, -f) (with l being left, t being top, n being near, r being right, b being bottom, and f being far) and maps it to a cube with the coordinates of the same corners being (-1, 1, 1) […]

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Hit Detection Experiments

I decided I wanted to write an environment hit detection system the other day. My intention was to make a collidable image, by which I mean particles/circles could collide with arbitrary shapes based on the pixels of the image. Decided I could check if a line formed by the last position of the particle and […]

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LSP v0.8 Released

I finally made the first build of Livestream Processor! And it has a logo made by my friend Antonio Lassandro. The code snapshot is on Github here and the downloads are hosted on Google Code hopefully that will always show the v0.8 downloads, I had to link to a search result. Anyway, right now it's […]

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Livestream Processor

For the last two months I have been spending a lot of time working on a new program called, for lack of a better name, Livestream Processor. The plan is to be able to process video, mostly from livestreams, in a few specific ways. The inspiration comes from my Ludum Dare livestreams, I want to […]

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Ludum Dare 24

Original Post This time I'll be doing the jam though with a friend and fellow computer science major Brandon. I'll be streaming again and I'll do the live builds as well. Follow my progress: Stream Live build Oh and here's what I'll be using to actually make the game: Eclipse/Java 6 SFXR Gimp Dropbox Git […]

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Today I was reading Twitter and ran out of posts to view so I noticed my background. For more than a year my background has been a screenshot of this code: MatrixMult.java1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 public class MatrixMult { static int[][] mult(int[][] […]

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More Ideas - Math!

I recently discovered a book called Secrets of Mental Math: The Mathemagician’s Guide to Lightning Calculation and Amazing Math Tricks by Arthur Benjamin and Michael Shermer. Obviously I need a way to practice these techniques so I don’t forget them. This led me to an idea for a new android app that I will be […]

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Github, Ep1c G4m3 and ideas

I’ve started to rewrite Ep1c G4m3 because last time I changed the code to comply with a better rendering system I broke everything. I’ve already made a lot of improvements to the current code revision. I’ll do one huge commit once I’ve re-written everything. I wonder if I can import an SVN database into Github. […]

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It’s been a while since I’ve posted anything here. So here’s how life has been going. The first quarter of school is almost over now and my prediction was incorrect. I haven’t done any more programming than I did during the summer. I’ll attribute this to homework. I decided to prove to myself that I’m […]

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