Hotdog, Not a Hotdog

Ned Gulley
/
Hotdog, Not a Hotdog
on 4 Nov 2026
7
39
19
3
9976
game.m
function g = game()
%game Hotdog, Not a Hotdog: tap to reject anything that isn't the order.
%
%   You run quality control on a hotdog conveyor belt. The target order
%   is shown on the left; items ride up the belt on the right. Tap to
%   shove the reject arm across the belt and fling away anything that
%   doesn't match. Matching hotdogs that reach the top ship; anything
%   wrong that ships is a strike. Ship 10 to clear a round (new target,
%   faster belt). Three strikes and you're fired.
%
%   The harness catches clicks with WindowButtonDownFcn, which fires
%   whatever is under the pointer, so objects skip HitTest settings.

g.init   = @initState;
g.update = @updateState;
g.render = @renderFrame;
end

function s = initState(ax)
% Layout (world 800x600, y down): belt x 435-565, y 100-540, center x 500.
% The arm sits at y 280, rests at x 655, and reaches x 410.
s.t = 0;
s.off = 0;                     % belt tread offset
s.tg = [];
s = newGame(s);
s.st = 0;                      % 0 title, 1 playing, 2 round break, 3 fired
s.em = cellstr(reshape('🦆🍌🐟👟🥒👽🧦🍕🐱🧠💩🌮🍩🚀🐌👻🦄👁🍆🌵💀', 2, [])');

ax.YDir = 'reverse';
ax.Color = '#1F3650';
R = @(x, y, w, h, c, varargin) patch(ax, x + [0 w w 0], y + [0 0 h h], 'w', 'FaceColor', c, ...
    'EdgeColor', 'none', 'LineJoin', 'round', varargin{:});
T = @(x, y, str, z, c, varargin) text(ax, x, y, str, 'FontSize', z, 'Color', c, ...
    'FontWeight', 'bold', 'HorizontalAlignment', 'center', varargin{:});
gold = '#FFD700';

% Header and HUD
R(0, 0, 800, 48, '#C0392B');
T(400, 24, 'HOTDOG QUALITY CONTROL DEPARTMENT', 24, gold);
box = {'EdgeColor', gold, 'LineWidth', 2};
R(15, 58, 170, 44, '#0E1824', box{:});
R(605, 58, 180, 44, '#0E1824', box{:});
T(60, 80, 'SCORE', 18, gold);
s.g.sc = T(175, 80, '', 20, 'w', 'HorizontalAlignment', 'right');
T(650, 80, 'STRIKES', 13, 'w');
s.g.sk = T(700, 80, '', 22, '#E74C3C', 'HorizontalAlignment', 'left');

% Target order panel and round progress
R(25, 165, 250, 280, '#FFF8E0', 'EdgeColor', '#8B4513', 'LineWidth', 4);
R(25, 165, 250, 36, '#C0392B');
T(150, 183, 'TARGET ORDER', 18, gold);
h = mkDog(ax, 1.6);
h.t.Matrix = makehgtform('translate', [150 262 0], 'scale', 1.6);
s.g.tp = h.p;
s.g.tl = T(150, 380, '', 14, '#333');
s.g.fb = R(20, 160, 260, 290, 'none', 'EdgeColor', gold, 'LineWidth', 6);
R(25, 455, 250, 26, '#132030', 'EdgeColor', gold);
s.g.pf = R(27, 457, 0, 22, '#4CAF50');
s.g.pt = T(150, 468, '', 12, 'w');

% Conveyor belt
R(423, 88, 154, 464, '#2A2A2A');
R(435, 100, 130, 440, '#4A4A4A');
s.g.tr = R(0, 0, 0, 0, '#2E2E2E');   % treads: one thin rectangle per face
R(415, 60, 170, 18, '#4CAF50');
T(500, 69, '↑ SHIP ↑', 11, 'w');
R(300, 271, 105, 18, '#B8543F');
T(352, 280, '← REJECT CHUTE', 9, 'w');

% Item pool: each slot can show any hotdog or any emoji
for i = 10:-1:1
    h = mkDog(ax, 0.8);
    s.g.T(i) = h.t;
    s.g.B(i) = h.b;
    s.g.P(i, :) = h.p;
    s.g.E(i) = text(h.t, 0, 0, '', 'FontSize', 34, 'HorizontalAlignment', 'center');
end

% Floor (hides items as they emerge), arm, and score popups
R(0, 555, 800, 45, '#3A3530');
R(700, 220, 60, 130, '#555', 'EdgeColor', 'k');
R(712, 230, 36, 110, '#222');
s.g.cg = R(712, 0, 36, 0, '#4CAF50');    % recharge gauge
s.g.sh = R(0, 274, 0, 12, '#B0B0B0');
s.g.pl = R(0, 252, 0, 56, 'r', 'EdgeColor', '#5A1010', 'LineWidth', 2);
for i = 6:-1:1
    s.g.F(i) = T(0, 0, '', 20, 'w');
end

% Overlay for title, round break, and game over
s.g.ov = [R(0, 0, 800, 600, 'k', 'FaceAlpha', 0.78), T(400, 150, '', 36, gold), ...
    T(400, 300, '', 14, 'w'), T(400, 470, '', 18, gold)];
end

function h = mkDog(ax, z)
% Hotdog at the origin (about 86 x 40) inside an hgtransform. Topping
% positions are random but fixed for the life of the slot, so they
% never shimmer. z scales marker sizes and line widths.
h.t = hgtransform(ax);
h.b = hggroup(h.t);
% Outlines are an edgeless rim shape behind an edgeless fill, since
% patch edges leave a notch where the outline starts and ends.
P = @(x, y, c) patch(h.b, x, y, 'w', 'FaceColor', c, 'EdgeColor', 'none');
a = (1:48)'*pi/24;
E = @(x, y, rx, ry, c) P(x + rx*cos(a), y + ry*sin(a), c);
E(2, 22, 44, 5, '#3A3A3A');
E(0, -9, 42.3, 15.3, '#8B6332');      % back half of the bun
E(0, -9, 41, 14, '#D9A45E');
E(0, 11, 44.3, 15.3, '#8B6332');
E(0, 11, 43, 14, '#E8B973');
E(-3, 7, 33, 6, '#F3D199');
% Sausage: a tube with straight sides and round ends, centered at y = -3
b = (-8:8)'*pi/16;
C = @(r, c) P([29 + r*cos(b); -29 - r*cos(b)], -3 + r*[sin(b); -sin(b)], c);
C(10.8, '#5A1F10');
C(9.5, '#B8543F');
% Toppings, indexed alphabetically to match the topping mask:
% chili, ketchup, relish, slaw, tomato. Drawn bottom to top.
c = {'#6B3410', '#D32F2F', '#4CAF50', '#F5F5DC', '#FF4848'};
n = [16 14 30 28 5];
sz = [5 1 2 5 6];
m = 'o.s_s';
ls = {'none', '-'};
for k = [1 4 3 2 5]
    x = -30 + 60*rand(1, n(k));
    y = -10 + 5*rand(1, n(k));
    if k == 2                  % ketchup is a zigzag line
        x = -32 + 5*(0:13);
        y = -4 - 3*(-1).^(0:13);
    end
    h.p(k) = line(h.b, x, y, 'Color', c{k}, 'LineStyle', ls{1 + (k == 2)}, 'Marker', ...
        m(k), 'MarkerSize', sz(k)*z, 'MarkerFaceColor', c{k}, 'LineWidth', z + 1.7*z*(k == 2));
end
end

function s = updateState(s, dt, pressed)
s.t = s.t + dt;
t = s.t;
s.off = s.off + s.v*dt;
s.fl8 = s.fl8 - dt;
if pressed && s.st == 1 && t > s.cool
    % The arm is out briefly, then needs a full second to recharge, so
    % each push has to be timed.
    s.aa = t + 0.2;
    s.cool = t + 1;
elseif pressed && mod(s.st, 3) == 0 && t > s.lock
    s = newGame(s);
end
s.act = t < s.aa;
d = 655 - 245*s.act - s.ax;
s.ax = s.ax + sign(d)*min(abs(d), 2400*dt);

% Items: q = [x y vx vy angle spin]; rejected items fall.
% Popups: pp = [x y vx vy life].
z = 0*s.rj;
s.q = s.q + dt*[s.q(:, 3:4), z, 720*s.rj, s.q(:, 6), z];
s.pp = s.pp + dt*[s.pp(:, 3:4), repmat([0 140 -1], 6, 1)];

if s.st == 2 && t > s.rb
    s = newRound(s);
elseif s.st == 1
    s.sp = s.sp + dt;
    if s.sp >= s.si
        s.sp = s.sp - s.si;
        s = spawn(s);
    end
    y = s.q(:, 2);
    live = s.on & ~s.jd;
    good = ~s.w & all(s.M == s.tg, 2);    % matches the order
    % Arm plate (16x56) vs. item boxes (about 72x28). Rejecting a good
    % hotdog is a strike.
    for i = find(live & s.act & abs(s.ax - 8 - s.q(:, 1)) < 44 & abs(y - 280) < 42)'
        s = fling(s, i, [-580 -140 -6 - 5*rand]);
        if good(i)
            s = strike(s, i);
        else
            s = pop(s, i, 'REJECT!', '#FFA500');
        end
    end
    % Anything that reaches the top of the belt ships.
    for i = find(live & y < 92)'
        s.jd(i) = true;
        if good(i)
            s.score = s.score + 10*s.rd;
            s.n = s.n + 1;
            s = pop(s, i, "+" + 10*s.rd, '#4CD94F');
            s.q(i, 4) = -200;
            if s.n == 5 && s.pk < 3
                s.pe = t + 0.6;
                s.pk = 2;
            end
        else
            s = strike(s, i);
            s.q(i, [3 4 6]) = [80*rand - 40, -80, 8*rand - 4];
        end
    end
    if t > s.pe
        s.st = s.pk;
        s.pe = inf;
        s.rb = t + 2.2;
        s.lock = t + 0.8;
        if s.st == 2
            % Sweep in-flight items so nothing counts against the new target.
            i = find(s.on & ~s.jd);
            o = rand(size(i));
            s = fling(s, i, [-280 - 200*o, -100 - 60*o, 10*o - 5]);
        end
    end
end
s.on = s.on & abs(s.q(:, 1) - 400) < 500 & abs(s.q(:, 2) - 300) < 400;
end

function s = newGame(s)
s.q = zeros(10, 6);
s.w = zeros(10, 1);
[s.on, s.jd, s.rj] = deal(false(10, 1));
s.M = false(10, 5);           % topping mask per item
s.pp = zeros(6, 5);
s.fs = repmat({{'', 'w'}}, 6, 1);   % popup text and color
% k is strikes, rd the round, act whether the arm is out
[s.score, s.k, s.rd, s.act, s.aa, s.cool, s.lock, s.rb] = deal(0);
s.ax = 655;                    % arm plate x
s.pe = inf;                    % time of the pending round break or firing
s = newRound(s);
end

function s = newRound(s)
s.rd = s.rd + 1;
s.n = 0;                       % shipped this round
s.v = min(58 + 22*s.rd, 200);  % belt speed
s.si = max(1.61 - 0.11*s.rd, 1.05);    % spawn interval; floor > recharge
s.sp = -0.3;                   % spawn timer
s.pk = 0;                      % pending state
s.st = 1;
s = newTarget(s);
end

function s = newTarget(s)
m = s.tg;
while isequal(m, s.tg)
    m = rtop;
end
s.tg = m;
s.fl8 = 1.5;                   % gold flash around the panel
nm = "• " + ["CHILI" "KETCHUP" "RELISH" "SLAW" "TOMATO"];
s.tl = ["TOPPINGS:", nm(m)];
if ~any(m)
    s.tl = "PLAIN HOTDOG";
end
end

function m = rtop
% 25% plain, else one topping (60%) or two.
m = false(1, 5);
if rand > 0.25
    m(randperm(5, 1 + (rand > 0.6))) = true;
end
end

function s = spawn(s)
% About 45% the order, 37% the wrong hotdog, 18% not a hotdog at all.
i = find(~s.on, 1);
if isempty(i)
    return
end
r = rand;
m = s.tg;
while r > 0.45 && isequal(m, s.tg)
    m = rtop;
end
s.M(i, :) = m;
s.w(i) = (r > 0.82)*randi(21);
s.q(i, :) = [500 570 0 -s.v 0 0];
s.jd(i) = false;
s.rj(i) = false;
s.on(i) = true;
end

function s = strike(s, i)
s.k = s.k + 1;
s = pop(s, i, 'STRIKE!', '#E74C3C');
if s.k == 3
    s.pe = s.t + 0.7;
    s.pk = 3;
end
end

function s = fling(s, i, v)
s.jd(i) = true;
s.rj(i) = true;
s.q(i, [3 4 6]) = v;
end

function s = pop(s, i, str, c)
[~, j] = min(s.pp(:, 5));
s.pp(j, :) = [s.q(i, 1:2) 40*rand - 20, -110, 1.3];
s.fs{j} = {str, c};
end

function renderFrame(~, s)
g = s.g;
set(g.T, {'Visible'}, num2cell(s.on));
for i = find(s.on)'            % skipping idle slots saves redraw time
    q = s.q(i, :);
    g.T(i).Matrix = makehgtform('translate', [q(1:2) 0], 'zrotate', q(5), 'scale', 0.8);
    w = s.w(i);
    g.B(i).Visible = ~w;
    set(g.P(i, :), {'Visible'}, num2cell(s.M(i, :))');
    set(g.E(i), 'Visible', w > 0, 'String', s.em{max(w, 1)}, 'Rotation', -57.3*q(5));
end
set(g.tp, {'Visible'}, num2cell(s.tg)');
g.tl.String = s.tl;
g.fb.Visible = s.fl8 > 0 && mod(s.fl8, 0.3) > 0.15;   % blink

y = 540 - mod(s.off, 26) - 26*(0:16);
y(y < 102) = nan;
set(g.tr, 'XData', [435; 565; 565; 435] + 0*y, 'YData', [y; y; y + 3; y + 3]);
x = s.ax;
g.sh.XData = [x 700 700 x];
% Plate: grey while recharging, dark red when ready, bright red when out
c = {'#777', '#A93226', '#E74C3C'};
set(g.pl, 'XData', x - [16 0 0 16], 'FaceColor', c{1 + (s.t > s.cool) + 2*s.act});
g.cg.YData = 340 - [0 0 110 110]*min(1, 1 + s.t - s.cool);

g.sc.String = "" + s.score;
k = min(s.k, 3);
c = '●●●○○○';
g.sk.String = c(4 - k:6 - k);
n = min(s.n, 5);
g.pf.XData = 27 + [0 49.2 49.2 0]*n;
g.pt.String = "ROUND " + s.rd + " — " + n + " / 5 shipped";
for i = 1:6
    set(g.F(i), 'Position', s.pp(i, 1:2), 'String', s.fs{i}{1}, ...
        'Color', s.fs{i}{2}, 'Visible', s.pp(i, 5) > 0);
end

st = s.st;
h = {'HOTDOG, NOT A HOTDOG', {...
    'Tap to reject anything not on the order.', ...
    'The arm needs 1 s to recharge.', ...
    'Ship 5 to clear a round.', ...
    'Wrong ship or good reject = strike.', ...
    '3 strikes and you''re fired.'}, 'Tap SPACE or CLICK to start'};
if st == 2
    h = {"ROUND " + (s.rd + 1), 'New target! Belt speeds up!', ''};
elseif st == 3
    h = {'YOU''RE FIRED', "Score " + s.score + "  •  Round " + s.rd, 'Tap to try again'};
end
set(g.ov, 'Visible', st ~= 1);
g.ov(2).String = h{1};
g.ov(3).String = h{2};
set(g.ov(4), 'String', h{3}, 'FontSize', 18 + 1.5*sin(7*s.t), 'Visible', st ~= 1 && (st < 3 || s.t > s.lock));
end
Play Game
Preview

Play Game opens this in MATLAB Drive. Click Run this app there to play.