Recent blog entries for fzort

OMFG I KICKED ASS

"Congratulations! Protozoa has been chosen as the second place Best Game on Intel® Graphics AND fifth place Best Game on the Go winner in the 2008 Intel Game Demo Contest. We had over 329 games registered from 32 countries this year. Your winning entry was selected based on specifics outlined by category in the official rules."

I'm sick of hearing about Chrome. I don't care. Please stop it.

I've been toying a bit with CSG, using BSP trees. Here's a cow and a dodecahedron. Here's the cow minus the dodecahedron.

The idea is to use this in a (possibly multiplayer) 3D space combat game where you can punch new craters on asteroids. With some basic rigid body dynamics, it could look really cool. Unfortunately, the BSP tree approach seems to generate way too many polygons. I also had a look at the approach to CSG used in GtkRadiant. It's based on implicit convex volumes ("brushes") - a subtraction operation generates new brushes on demand. It could be made to work in real time. Next I'll work on a demo where you can interactively carve holes on an object using both approaches in order to compare them.

And this looks incredible.

No news from Intel yet. This probably means I didn't win.

Bummer.

... in NEGATIVE TIME!

Just saw a video of Damian Conway's OSCon presentation (download - ~460 MB!). This guy is my new hero.

"To be a good programmer you have to actually program. This is something that doesn't happen. (...) You start going to meetings, you start doing design, all the rest of it, and you stop coding. And if you get promoted, you're literally promoted out of the opportunity to do any coding. I think that's a problem. If you want to be a really good tennis player, you will go out and practice every day. If you want to be a great martial artist, you will be on the dojo every single day. If you want to be a great programmer you have to code every day, even if you have to find time on your own to do that. If you're up at 11 PM, 3 AM, some of that time at least has to be spent coding, because as soon as you get rusty you start dying as a coder."

                   -- Damian Conway interview

Quit Yahoo! after three months.

MarkAtwood: wrong.

(Well, you may be right about outrunning a cheetah, though.)

OpenGL Optimization Notes - 1

The particles in my game are rendered as texture-mapped, transparent quads [1]. When I had lots (>1000) of particles on the screen at the same time, there was noticeable performance degradation with my GeForce FX. Now, to render the quads, I'm filling a big vertex array with the coordinates/color/texture coordinates for the vertices of all particles in the scene, and calling glDrawArray once. Initially, I assumed that the problem was caused by limited CPU->GPU bandwidth, so I tried different things: changed the data type for glColorArray from GL_FLOAT to GL_UNSIGNED_BYTE, did a similar thing for the texture coordinate array, and tried to use the vertex buffer object extension [2]. None of these improved things. Then I changed the texture size from 128x128 to 16x16 (the particles are quite small, so visually the change wasn't noticeable), and suddenly everything got quite fast!

In fact, since the texture is quite simple (just a linear function of distance from a point the center of the texture), perhaps I don't even need the texture - I can compute the intensity inside a fragment shader (nVidia says that their GPUs can compute square roots essentially for nothing). I'll try that some day.

[1] I can't use the point sprite extension since I want the particles to be rotated. Also, Intel graphics hardware doesn't support that extension (the initial motivation for the game was Intel's Game Demo Contest).

[2] There wasn't noticeable performance improvement on the GeForce, and - worse - despite being advertised as available by the Intel OpenGL drivers, the program exploded on *ndows, and didn't display anything on Linux (it worked fine with both nVidia and Mesa).

I've been getting stuff like this all the time:

ship.c: In function ‘update_ship’:
ship.c:552: internal compiler error: in loc_descriptor, at dwarf2out.c:9025
Please submit a full bug report,
with preprocessed source if appropriate.

Either it's a cosmic ray shower caused by abnormal sunspot activity, or my memories are really busted. Hope they hang on until at least the contest deadline.

Really tired, but hey, YOU GOT A HIGH SCORE!

Depressing

Alan Turing would not be amused if he knew that this would be the outcome of "On computable numbers, with an application to the Entscheidungsproblem".