tuket

bool rayVsCircle(float& depth,
    glm::vec2 rayOrig, glm::vec2 rayDir,
    glm::vec2 circlePos, float circleRad)
{
    const float R = circleRad;
    const glm::vec2 op = circlePos - rayOrig;
    if(dot(op, op) < R*R) { // is rayOrigin inside the circle ?
        depth = 0;
        return true;
    }

tuket

#include <glm/glm.hpp>
#include <glm/gtc/constants.hpp>

constexpr float PI = glm::pi<float>();
using glm::vec3;

/*static void generateIcosahedronVerts(vec3 verts[12])
{
	using glm::sqrt;
	using glm::mat2;

tuket

const std = @import("std");
const warn = std.debug.warn;
const fmt = std.fmt;

const c = @cImport({
    @cInclude("SDL2/SDL.h");
});
const assert = @import("std").debug.assert;

const SDL_WINDOWPOS_UNDEFINED = @bitCast(c_int, c.SDL_WINDOWPOS_UNDEFINED_MASK);

tuket

// compile in ubuntu:
// $ zig build-exe paint.zig --library SDL2 --library SDL2main --library c -isystem "/usr/include" --library-path "/usr/lib/x86_64-linux-gnu"

const std = @import("std");
const warn = std.debug.warn;
const fmt = std.fmt;

const c = @cImport({
    @cInclude("SDL2/SDL.h");
});

tuket

/*
When I was looking at the disassembly of my compiler, I noticed that it decided to, instead of
dividing by 3, multiply by 2863311531.
At first I was puzzled by this, but it wasn't as complicated as I thought.
So it turns out that an integer division can be decomposed in two operatations:
1) A bit shift: that's just deviding by a power of 2
2) A multiplication that overflows
The compiler dicides to do this because division is an expensive operation for CPUs
So here I wrote some code that computes the right pair of values for the given divider
*/

tuket

#include <variant>
#include <string>
#include <vector>
#include <exception>
#include <functional>
#include <iostream>

using namespace std;

void numToStringNum(variant<int, string>& x)

tuket

#include <iostream>
#include <vector>
#include <algorithm>
#include <numeric>
#include <chrono>

using namespace std;

template <typename T>
void vecSwap(vector<T>& v, int i1, int  i2, int n) {

tuket

1

2

tuket

#include <iostream>

// there are 3 sticks: 0, 1, 2
void move(int x, int from, int to)
{
    if(x == 1) printf("%d->%d\n", from, to);
    else
    {
        int other = 3-from-to;
        move(x-1, from, other);

tuket

#include <iostream>
#include <CppUTest/CommandLineTestRunner.h>
#include <CppUTest/TestHarness.h>
#include <numeric>

using namespace std;

// (x^p)%n
unsigned powMod(unsigned x, unsigned p, unsigned n)
{