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Mārtiņš Možeiko mmozeiko

  • RAD Game Tools
  • Kirkland, WA
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View perfect-quantization-dxt-endpoints.txt
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);
JarkkoPFC / sphere_screen_extents.h
Last active May 17, 2020
Calculates view space 3D sphere extents on the screen
View sphere_screen_extents.h
struct vec3f {float x, y, z;};
struct vec4f {float x, y, z, w;};
struct mat44f {vec4f x, y, z, w;};
// sphere_screen_extents
// Calculates the exact screen extents xyzw=[left, bottom, right, top] in
// normalized screen coordinates [-1, 1] for a sphere in view space. For
// performance, the projection matrix (v2p) is assumed to be setup so that
vurtun / x11_clipboard.c
Last active Dec 15, 2019
X11 clipboard
View x11_clipboard.c
static char*
sys_clip_get(struct sys *s, Atom selection, Atom target)
struct sys_x11 *x11 = s->platform;
/* blocking wait for clipboard data */
XEvent notify;
XConvertSelection(x11->dpy, selection, target, selection, x11->helper, CurrentTime);
while (!XCheckTypedWindowEvent(x11->dpy, x11->helper, SelectionNotify, &notify)) {
View rpi_gpu_usage_monitor.cpp
#include <stdio.h>
#include <errno.h>
#include <sys/types.h>
#include <unistd.h>
#include <string.h>
#include <assert.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <stdlib.h>
#include <sys/ioctl.h>
twoscomplement / TransientFunction.h
Last active Apr 15, 2018
TransientFunction: A light-weight alternative to std::function [C++11]
View TransientFunction.h
// TransientFuction: A light-weight alternative to std::function [C++11]
// Pass any callback - including capturing lambdas - cheaply and quickly as a
// function argument
// Based on:
// - No instantiation of called function at each call site
// - Simple to use - use TransientFunction<> as the function argument
// - Low cost: cheap setup, one indirect function call to invoke

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](

vurtun / defl.c
Last active Jun 6, 2020
Full deflate/inflate implementation in ~300 LoC
View defl.c
/* ===============================================================
* ===============================================================
* public domain - no warranty implied; use at your own risk
* References:
#include <stdlib.h>
View gui.c
/* ===========================================================================
* =========================================================================== */
/* Proof of Concept GUI:
* - PoC UI implementation in ~2.5kLOC of C89 (ANSI C)
* => Core solutions has no external dependencies (removing standard library dependency is trival)
* => Does not use or require any special language constructs or macro constructs just pointers and enums
* - Combines both "retained" and "immediate mode" UI by providing control over update frequency
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