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@silvesthu
silvesthu / GPUOptimizationForGameDev.md
Last active May 12, 2024 22:42
GPU Optimization for GameDev
@jboner
jboner / latency.txt
Last active May 12, 2024 19:52
Latency Numbers Every Programmer Should Know
Latency Comparison Numbers (~2012)
----------------------------------
L1 cache reference 0.5 ns
Branch mispredict 5 ns
L2 cache reference 7 ns 14x L1 cache
Mutex lock/unlock 25 ns
Main memory reference 100 ns 20x L2 cache, 200x L1 cache
Compress 1K bytes with Zippy 3,000 ns 3 us
Send 1K bytes over 1 Gbps network 10,000 ns 10 us
Read 4K randomly from SSD* 150,000 ns 150 us ~1GB/sec SSD
@mbinna
mbinna / effective_modern_cmake.md
Last active May 11, 2024 09:23
Effective Modern CMake

Effective Modern CMake

Getting Started

For a brief user-level introduction to CMake, watch C++ Weekly, Episode 78, Intro to CMake by Jason Turner. LLVM’s CMake Primer provides a good high-level introduction to the CMake syntax. Go read it now.

After that, watch Mathieu Ropert’s CppCon 2017 talk Using Modern CMake Patterns to Enforce a Good Modular Design (slides). It provides a thorough explanation of what modern CMake is and why it is so much better than “old school” CMake. The modular design ideas in this talk are based on the book [Large-Scale C++ Software Design](https://www.amazon.de/Large-Scale-Soft

@sebbbi
sebbbi / FastUniformLoadWithWaveOps.txt
Last active May 11, 2024 07:37
Fast uniform load with wave ops (up to 64x speedup)
In shader programming, you often run into a problem where you want to iterate an array in memory over all pixels in a compute shader
group (tile). Tiled deferred lighting is the most common case. 8x8 tile loops over a light list culled for that tile.
Simplified HLSL code looks like this:
Buffer<float4> lightDatas;
Texture2D<uint2> lightStartCounts;
RWTexture2D<float4> output;
[numthreads(8, 8, 1)]
@rygorous
rygorous / iggy_focus.cpp
Created October 14, 2013 19:46
Iggy focus handling
enum FocusDir
{
DIR_W,
DIR_E,
DIR_N,
DIR_S
};
static FocusDir get_quadrant(float dx, float dy)
{
@raysan5
raysan5 / custom_game_engines_small_study.md
Last active May 7, 2024 19:39
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

@TheRealMJP
TheRealMJP / Tex2DCatmullRom.hlsl
Last active May 7, 2024 07:11
An HLSL function for sampling a 2D texture with Catmull-Rom filtering, using 9 texture samples instead of 16
// The following code is licensed under the MIT license: https://gist.github.com/TheRealMJP/bc503b0b87b643d3505d41eab8b332ae
// Samples a texture with Catmull-Rom filtering, using 9 texture fetches instead of 16.
// See http://vec3.ca/bicubic-filtering-in-fewer-taps/ for more details
float4 SampleTextureCatmullRom(in Texture2D<float4> tex, in SamplerState linearSampler, in float2 uv, in float2 texSize)
{
// We're going to sample a a 4x4 grid of texels surrounding the target UV coordinate. We'll do this by rounding
// down the sample location to get the exact center of our "starting" texel. The starting texel will be at
// location [1, 1] in the grid, where [0, 0] is the top left corner.
float2 samplePos = uv * texSize;
@Reedbeta
Reedbeta / cool-game-programming-blogs.opml
Last active May 5, 2024 18:07
List of cool blogs on game programming, graphics, theoretical physics, and other random stuff
<?xml version="1.0" encoding="UTF-8"?>
<opml version="1.0">
<head>
<title>Graphics, Games, Programming, and Physics Blogs</title>
</head>
<body>
<outline text="Tech News" title="Tech News">
<outline type="rss" text="Ars Technica" title="Ars Technica" xmlUrl="http://feeds.arstechnica.com/arstechnica/index/" htmlUrl="https://arstechnica.com"/>
<outline type="rss" text="Polygon - Full" title="Polygon - Full" xmlUrl="http://www.polygon.com/rss/index.xml" htmlUrl="https://www.polygon.com/"/>
<outline type="rss" text="Road to VR" title="Road to VR" xmlUrl="http://www.roadtovr.com/feed" htmlUrl="https://www.roadtovr.com"/>
@pervognsen
pervognsen / rh_grow.c
Last active March 12, 2024 20:23
// This can grow a Robin Hood linear probing hash table near word-at-a-time memcpy speeds. If you're confused why I use 'keys'
// to describe the hash values, it's because my favorite perspective on Robin Hood (which I learned from Paul Khuong)
// is that it's just a sorted gap array which is MSB bucketed and insertion sorted per chain:
// https://pvk.ca/Blog/2019/09/29/a-couple-of-probabilistic-worst-case-bounds-for-robin-hood-linear-probing/
// The more widely known "max displacement" picture of Robin Hood hashing also has strengths since the max displacement
// can be stored very compactly. You can see a micro-optimized example of that here for small tables where the max displacement
// can fit in 4 bits: Sub-nanosecond Searches Using Vector Instructions, https://www.youtube.com/watch?v=paxIkKBzqBU
void grow(Table *table) {
u64 exp = 64 - table->shift;
// We grow the table downward in place by a factor of 2 (not counting the overflow area at table->end).
@castano
castano / perfect-quantization-dxt-endpoints.txt
Last active February 18, 2024 03:31
Perfect Quantization of DXT endpoints
-------------------------------------
One of the issues that affect the quality of most DXT compressors is the way floating point colors are rounded.
For example, stb_dxt does:
max16 = (unsigned short)(stb__sclamp((At1_r*yy - At2_r*xy)*frb+0.5f,0,31) << 11);
max16 |= (unsigned short)(stb__sclamp((At1_g*yy - At2_g*xy)*fg +0.5f,0,63) << 5);
max16 |= (unsigned short)(stb__sclamp((At1_b*yy - At2_b*xy)*frb+0.5f,0,31) << 0);