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@Nexuapex
Nexuapex / kahan3.c
Created August 23, 2012 05:12
Kahan summation (3-way)
float sum(float x0, float x1, float x2)
{
float accum = x0 + x1;
float excess = (accum - x0) - x1;
float addend = x2 - excess;
return accum + addend;
}
@Nexuapex
Nexuapex / dump.lua
Created June 17, 2012 02:50
Dumping a description of a Lua value
local dump_table_threshold = 3
local dump_indent = (" "):rep(4)
local dumptable = {
["nil"] = tostring,
["number"] = tostring,
["string"] = function(value) return "\"" .. value .. "\"" end,
["boolean"] = tostring,
["table"] = function(value, depth, markers)
if markers[value] then
@Nexuapex
Nexuapex / reinterpret_f32_i32_sse.cc
Created February 18, 2012 05:10
Reinterpreting int ⇔ float with SSE
#include <xmmintrin.h>
inline int as_int_bitwise(float a)
{
return _mm_cvtsi128_si32(_mm_set_ss(a));
}
inline float as_float_bitwise(int a)
{
return _mm_cvtss_f32(_mm_cvtsi32_si128(a));
@Nexuapex
Nexuapex / icosahedron.cc
Created February 7, 2012 10:33
Icosahedron
static GLfloat const minor = 0.5257311f;
static GLfloat const major = 0.8506508f;
float const icosahedron_position[12][3] = {
{0.f, +minor, +major},
{0.f, +minor, -major},
{0.f, -minor, +major},
{0.f, -minor, -major},
{+major, 0.f, +minor},
{+major, 0.f, -minor},
@Nexuapex
Nexuapex / 7segment.c
Created October 29, 2011 04:39
7-segment display in 50 lines of C99.
#include <stdio.h>
int const schematic[7][7] = {
{0,1,1,1,1,0,0},
{2,0,0,0,0,3,0},
{2,0,0,0,0,3,0},
{0,4,4,4,4,0,0},
{5,0,0,0,0,6,0},
{5,0,0,0,0,6,0},
{0,7,7,7,7,0,0},