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Vivitsu Maharaja vivitsu

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@katef
katef / plot.awk
Last active October 7, 2024 11:20
#!/usr/bin/awk -f
# This program is a copy of guff, a plot device. https://github.com/silentbicycle/guff
# My copy here is written in awk instead of C, has no compelling benefit.
# Public domain. @thingskatedid
# Run as awk -v x=xyz ... or env variables for stuff?
# Assumptions: the data is evenly spaced along the x-axis
# TODO: moving average
@pervognsen
pervognsen / hejlsberg_fp.asm
Created June 21, 2020 03:46
; Math48 Floating Point Package
; Version 1.1 Revision 1
; by Anders Hejlsberg
; 2532 Bytes
;HOPTABEL
JP FPADD
JP FPSUB
JP FPMUL
@pervognsen
pervognsen / tp3.asm
Created June 21, 2020 00:20
; https://web.archive.org/web/20190701203222/https://www.pcengines.ch/tp3.htm
; The disassembler was applied to a copy of TP 3.01A downloaded from WinWorld.
; I postprocessed the disassembly with a script to clean up spacing and column alignment.
; *** TURBO PASCAL version 3.01 A source code
; ***
; *** commented by Pascal Dornier
; *** all rights reserved
; "***
cseg $100 ; "COM file...
@raysan5
raysan5 / custom_game_engines_small_study.md
Last active October 24, 2024 16:16
A small state-of-the-art study on custom engines

CUSTOM GAME ENGINES: A Small Study

a_plague_tale

A couple of weeks ago I played (and finished) A Plague Tale, a game by Asobo Studio. I was really captivated by the game, not only by the beautiful graphics but also by the story and the locations in the game. I decided to investigate a bit about the game tech and I was surprised to see it was developed with a custom engine by a relatively small studio. I know there are some companies using custom engines but it's very difficult to find a detailed market study with that kind of information curated and updated. So this article.

Nowadays lots of companies choose engines like Unreal or Unity for their games (or that's what lot of people think) because d

@silvesthu
silvesthu / GPUOptimizationForGameDev.md
Last active November 12, 2024 05:26
GPU Optimization for GameDev
@rygorous
rygorous / avx_sigh.md
Last active June 1, 2024 02:05

why doesn't radfft support AVX on PC?

So there's two separate issues here: using instructions added in AVX and using 256-bit wide vectors. The former turns out to be much easier than the latter for our use case.

Problem number 1 was that you positively need to put AVX code in a separate file with different compiler settings (/arch:AVX for VC++, -mavx for GCC/Clang) that make all SSE code emitted also use VEX encoding, and at the time radfft was written there was no way in CDep to set compiler flags for just one file, just for the overall build.

[There's the GCC "target" annotations on individual funcs, which in principle fix this, but I ran into nasty problems with this for several compiler versions, and VC++ has no equivalent, so we're not currently using that and just sticking with different compilation units.]

The other issue is to do with CPU power management.

@paniq
paniq / ellipsoid_frustum.md
Last active December 30, 2021 20:13
Ellipsoid Frustum Intersection

Ellipsoid Frustum Intersection

Yesterday I posted a problem to math stack exchange that bothered me for a while now, and right after I've had a few exchanges on Twitter, I got inspired to attempt a solution.

Here it goes. It's 100% untested but I'm fairly certain that it will work.

The problem is about a form of refining raytracing where we render a big list of convex 3D brushes (and I decided to start with Ellipsoids, since they're so useful) to the screen or a shadow map, without any prebuilt accelleration structure. How does it work? Well, if we had a way to figure out for a portion of the frustum whether it contained a brush, we could

  1. Start with a very low resolution
@rygorous
rygorous / mergesort_kit.cpp
Last active August 28, 2023 10:13
int16 mergesort construction kit
#include <emmintrin.h>
#include <tmmintrin.h> // for PSHUFB; this isn't strictly necessary (see comments in reverse_s16)
typedef int16_t S16;
typedef __m128i Vec;
static inline Vec load8_s16(const S16 *x) { return _mm_loadu_si128((const __m128i *) x); }
static inline void store8_s16(S16 *x, Vec v) { _mm_storeu_si128((__m128i *) x, v); }
static inline void sort_two(Vec &a, Vec &b) { Vec t = a; a = _mm_min_epi16(a, b); b = _mm_max_epi16(b, t); }
@djg
djg / reading-list.md
Last active February 19, 2024 18:09
Fabian's Recommened Reading List
@nothings
nothings / kotaku_hzd.md
Last active September 4, 2024 06:33
Why Frustum Culling Matters, and Why It's Not Important

There is a nice GIF illustrating a technique called "frustum culling" in this Kotaku article: http://kotaku.com/horizon-zero-dawn-uses-all-sorts-of-clever-tricks-to-lo-1794385026

The interwebs being what they are, this has also led to some controversy.

Some people have interpreted the opening sentence "Every time you move the camera in Horizon Zero Dawn, the game is doing all sorts of under-the-hood calculations, loading and unloading chunks of world to ensure that it all runs properly," as being about the GIF; that's not what frustum culling does, but that's probably not what the article's author meant anyway.