JS1k: The JavaScript code golfing competition

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t,l=2r=parseInt("axgulq06kf",36).toStrVg(2).split(""s=.4i=n=e=2,y=oM=[],p=>{c=o)*a,a*o+c)Ut+=cX)UWi=t,n=e},f)=>|t|a||5<||t||15*tX]xh=0<t?~~(W1)-e:ceil(e-1)-e,a=h*a/t,0==t?{b:9}:{x:o?nX:Wh,y:o?Wh:nX,b:h*hX*a}k,h5*.y-(o?h)+.x-(n?ta.c=t||5t],aD=Wsqrt.bau=>>M[t.keyCode%37];AA;A++)b.VnerHTML+="<p =display:VlVe-block>"+"JS1K"[A%4]+"</p>"	I=d.querySeEctorAll("p"Fdown=u(1up=u(0setInterval(function(t){.004,M[0-
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-U-XD-F]/.exec(_);)with(_.split(G))_=join(shift());eval('var '+_)

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

// Based on a canvas raycaster build by Laerin
// https://codepen.io/xgundam05/pen/vcBbL

var CIRCLE = Math.PI * 2;
const wall_text = 'JS1K';
let RayMap_walls = parseInt("axgulq06kf", 36).toString(2).split(''),
    RayMap_width = 5,
    RayMap_height = 10,
    RayCamera_fov = Math.PI * 0.4,
    RayCamera_range = 14,
    RayCamera_lightRange = 5,
    p_x, p_y,
    RayCamera_p_x = p_x = 3,
    RayCamera_p_y = p_y = 4,
    dir,
    RayCamera_dir = dir = 0,
    RaycastRenderer_height = 9,
    RaycastRenderer_resolution = 28,
    // 37 - l, 39 - r, 38 - f, 40 - b
    Controls_states = [],
    lastTime = 0,
    str = '',
    rot = (angle) => {
        dir = (dir + angle + CIRCLE) % (CIRCLE);
        RayCamera_dir = dir;
    },
    walk = (distance) => {
        var dx = Math.cos(dir) * distance;
        var dy = Math.sin(dir) * distance;
        if (RayMap_Get(p_x + dx, p_y) <= 0) p_x += dx;
        if (RayMap_Get(p_x, p_y + dy) <= 0) p_y += dy;
        RayCamera_p_x = p_x;
        RayCamera_p_y = p_y;
    },
    update = (seconds) => {
        if (Controls_states[0]) rot(-Math.PI * seconds);
        if (Controls_states[2]) rot(Math.PI * seconds);
        if (Controls_states[1]) walk(3 * seconds);
        if (Controls_states[3]) walk(-3 * seconds);
    };

function RayMap_Get(x, y) {
    x = x | 0;
    y = y | 0;
    if (x < 0 || x >= RayMap_width || y < 0 || y >= RayMap_height) return -1;
    return RayMap_walls[y * RayMap_width + x];
};

function RayMap_Raycast(x, y, angle, range) {
    var cells = [];
    var sin = Math.sin(angle);
    var cos = Math.cos(angle);

    var stepX, stepY, nextStep;
    nextStep = { x, y, cell: 0, distance: 0 };
    do {
        cells.push(nextStep);
        if (nextStep.cell > 0)
            break;
        stepX = RayMap___step(sin, cos, nextStep.x, nextStep.y);
        stepY = RayMap___step(cos, sin, nextStep.y, nextStep.x, true);
        nextStep = stepX.length2 < stepY.length2
            ? RayMap___inspect(stepX, 1, 0, nextStep.distance, cos, sin)
            : RayMap___inspect(stepY, 0, 1, nextStep.distance, cos, sin);
    } while (nextStep.distance <= range);

    return cells;
};

function RayMap___step(rise, run, x, y, inverted) {
    var dx = run > 0 ? ~~(x + 1) - x : Math.ceil(x - 1) - x;
    var dy = dx * rise / run;
    return (run === 0) ? { length2: 9 } : {
        x: inverted ? y + dy : x + dx,
        y: inverted ? x + dx : y + dy,
        length2: dx * dx + dy * dy
    };
};

function RayMap___inspect(step, shiftX, shiftY, distance, cos, sin) {
    var dx = cos < 0 ? shiftX : 0;
    var dy = sin < 0 ? shiftY : 0;
    var index = (((step.y - dy) | 0) * RayMap_width) + ((step.x - dx) | 0);
    step.cell = (index < 0 || index >= 440) ? -1 : RayMap_walls[index];
    step.distance = distance + Math.sqrt(step.length2);
    return step;
};

function RayCamera_Rotate(angle) {
    RayCamera_dir = (RayCamera_dir + angle + CIRCLE) % (CIRCLE);
}

function RaycastRenderer___project(height, angle, distance) {
    var z = distance * Math.cos(angle);
    var wallHeight = RaycastRenderer_height * height / z;
    return wallHeight;
};

function RaycastRenderer___drawColumn(column, ray, angle) {
    var hit = -1;
    while (++hit < ray.length && ray[hit].cell <= 0);

    if (hit < ray.length) {
        var step = ray[hit];
        var wall = RaycastRenderer___project(1, angle, step.distance);
        const alpha = 1 - Math.max((step.distance) / RayCamera_lightRange, 0);
        els[column].style.opacity = alpha;
        els[column].style.transform = 'scaleY(' + wall + ')';
    }
};

function RaycastRenderer___drawColumns() {
    for (var col = 0; col < RaycastRenderer_resolution; col++) {
        var angle = RayCamera_fov * (col / RaycastRenderer_resolution - 0.5);
        var ray = RayMap_Raycast(RayCamera_p_x, RayCamera_p_y, RayCamera_dir + angle, RayCamera_range);
        RaycastRenderer___drawColumn(col, ray, angle);
    }
};


function Controls_onKey(val, e) {
    return (e) => {
        Controls_states[e.keyCode%37] = val;
    }
};

for (let i = 0; i < RaycastRenderer_resolution; i++) {
    str += '<p style="display:inline-block;margin-top:99px">' + wall_text[i % wall_text.length] + '</p>';
}

b.innerHTML = str;
let els = d.querySelectorAll('p');

d.onkeydown = Controls_onKey(1);
d.onkeyup = Controls_onKey(0);

function UpdateRender() {
    var seconds = 0.004;
    update(seconds);
    RaycastRenderer___drawColumns();
}
setInterval(UpdateRender);