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@d7samurai
d7samurai / .readme.md
Last active October 4, 2024 19:02
Minimal D3D11 sprite renderer NEO

sponsored by SuperNeo copy 4

Minimal D3D11 sprite renderer NEO

Ultra-compact sprite rendering code with example frame animation logic. This release contains tech bits from the upcoming SuperNeo™ 2D game engine and includes rotation, anchor/pivot point, color filtering, alpha blending and built-in antialiased point sampling. As usual: complete, runnable single-function app. ~150 LOC. No modern C++, OOP or (other) obscuring cruft.

Minimal D3D11 sprite renderer NEO 1337

Sprites are rendered back-to-front (AKA "painter's algorithm") in the order they are submitted, as one draw call. The provided setup employs a single texture atlas containing all the sprite graphics.

The renderer is "im

@JiayinCao
JiayinCao / tiny_fiber.h
Last active September 9, 2024 00:15
Tiny Fiber ( A razor thin cross platform fiber library )
/*
MIT License
Copyright (c) 2023 Jiayin Cao
Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
in the Software without restriction, including without limitation the rights
to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the Software is
@mmozeiko
mmozeiko / upng.h
Last active February 25, 2024 08:08
uncompressed png writer & reader
#pragma once
// uncompressed png writer & reader
// supports only 8-bit and 16-bit formats
// Performance comparison for 8192x8192 BGRA8 image (256MB)
// Compiled with "clang -O2", AVX2 requires extra "-mavx2" or "/arch:AVX2" argument
//
// For libpng (compressed) uses default libpng/zlib compression settings
// For libpng (uncompressed) case following two functions are used:
@d7samurai
d7samurai / .readme.md
Last active October 3, 2024 15:29
Minimal D3D11 bonus material: pixel art antialiasing

Minimal D3D11 bonus material: pixel art antialiasing

A minimal Direct3D 11 implementation of "antialiased point sampling", useful for smooth fractional movement and non-integer scaling of pixel art AKA "fat pixel" aesthetics.

Also view below side-by-side point sampling comparison on YouTube (video is zoomed in to counter implicit downsampling & compression artifacts and make aa effect more apparent) or check out the Shadertoy.

skull

The actual sampler is set to bilinear filtering (the default D3D11 sampler state) in order to utilize single texture-read hardware interpolation, then emulating point sampling in the shader and applying AA at the fat pixel boundaries. Use with premultiplied alpha textures* and keep a one pixel transparent border around each sprite/tile.

@vassvik
vassvik / Simulation_Projection.md
Last active September 22, 2024 03:02
Realtime Fluid Simulation: Projection

Realtime Fluid Simulation: Projection

The core of most real-time fluid simulators, like the one in EmberGen, are based on the "Stable Fluids" algorithm by Jos Stam, which to my knowledge was first presented at SIGGRAPH '99. This is a post about one part of this algorithm that's often underestimated: Projection

MG4_F32.mp4

Stable Fluids

The Stable Fluids algorithm solves a subset of the famous "Navier Stokes equations", which describe how fluids interact and move. In particular, it typically solves what's called the "incompressible Euler equations", where viscous forces are often ignored.

@d7samurai
d7samurai / .readme.md
Last active October 3, 2024 15:28
Minimal D3D11 pt2

Minimal D3D11 pt2

Follow-up to Minimal D3D11, adding instanced rendering. As before: An uncluttered Direct3D 11 setup & basic rendering primer / API familiarizer. Complete, runnable Windows application contained in a single function and laid out in a linear, step-by-step fashion. No modern C++ / OOP / obscuring cruft.

The main difference here is that the hollow cube is rendered using DrawIndexedInstanced (which saves a lot of vertices compared to the original, so model data is now small enough to be included in the source without being too much in the way), but also all trigonometry and matrix math is moved to the vertex shader, further simplifying the main code.

Each instance is merely this piece of geometry, consisting of 4 triangles:

instanced1

..which is th

@ibireme
ibireme / kpc_demo.c
Last active October 2, 2024 17:13
A demo shows how to read Intel or Apple M1 CPU performance counter in macOS.
// =============================================================================
// XNU kperf/kpc demo
// Available for 64-bit Intel/Apple Silicon, macOS/iOS, with root privileges
//
//
// Demo 1 (profile a function in current thread):
// 1. Open directory '/usr/share/kpep/', find your CPU PMC database.
// M1 (Pro/Max/Ultra): /usr/share/kpep/a14.plist
// M2 (Pro/Max): /usr/share/kpep/a15.plist
// M3: /usr/share/kpep/as1.plist
// Estimating CPU frequency...
// CPU frequency: 4.52 GHz
// sum1: value = 15182118497126522709, 0.31 secs, 5.14 cycles/elem
// sum2: value = 15182118497126522709, 0.17 secs, 2.93 cycles/elem
#define RW(x) asm("" : "+r"(x))
typedef struct Node {
u64 value;
struct Node *next;
@pervognsen
pervognsen / shift_dfa.md
Last active August 21, 2024 09:43
Shift-based DFAs

A traditional table-based DFA implementation looks like this:

uint8_t table[NUM_STATES][256]

uint8_t run(const uint8_t *start, const uint8_t *end, uint8_t state) {
    for (const uint8_t *s = start; s != end; s++)
        state = table[state][*s];
    return state;
}
@mmozeiko
mmozeiko / build.cmd
Last active October 3, 2024 15:07
download & build llvm+clang on Windows
@echo off
setlocal enabledelayedexpansion
rem !!! build requirements !!!
rem Visual Studio 2022 - https://visualstudio.microsoft.com/vs/
rem 7-Zip - https://www.7-zip.org/download.html
rem Python - https://www.python.org/downloads/
rem CMake - http://www.cmake.org/download/
rem ninja.exe - https://github.com/ninja-build/ninja/releases/latest