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// Handwritten JavaScript reference for examples/charge.pure.
// This fixed app has no source compiler, live apply, or state-name migration.
// Its scene and behavior must be changed by editing this JavaScript file.
export function createChargeModel() {
const held = new Set();
let holding = 0, charge = 0, y = 240, velocity = 0, tick = 0;
const checkInput = name => {
if (name !== 'jump') throw new Error(`Unknown input: ${name}`);
};
const model = {
down(name = 'jump', source = 'external') {
checkInput(name);
const wasDown = held.size > 0;
held.add(source);
if (!wasDown && y >= 240) {
holding = 1;
charge = 0;
}
return 0;
},
up(name = 'jump', source = 'external') {
checkInput(name);
if (!held.delete(source) || held.size) return 0;
if (holding) {
velocity = -(160 + charge * 300);
holding = 0;
charge = 0;
}
return 0;
},
frame(count = 1) {
if (!Number.isInteger(count) || count < 0 || count > 600) {
throw new Error('Frame count must be an integer from 0 through 600.');
}
const dt = 1 / 60;
for (let frame = 0; frame < count; frame++) {
if (holding) charge = Math.min(Math.max(charge + dt, 0), 1);
velocity = velocity + 600 * dt;
y = y + velocity * dt;
if (y >= 240) { y = 240; velocity = 0; }
tick++;
}
return 0;
},
releaseAll() {
for (const source of [...held]) model.up('jump', source);
return 0;
},
reset() {
held.clear();
holding = 0; charge = 0; y = 240; velocity = 0; tick = 0;
},
snapshot() {
return {
states: { holding, charge, y, velocity }, tick,
held: held.size ? ['jump'] : [],
views: [
{ id: 'floor', type: 'box', x: 40, y: 261, width: 560, height: 4, color: '#356548' },
{ id: 'actor', type: 'circle', x: 180, y, radius: 20, color: '#c78638' },
{ id: 'meter', type: 'box', x: 80, y: 80, width: charge * 200, height: 12, color: '#c78638' },
{ id: 'amount', type: 'text', x: 80, y: 60, value: charge, prefix: 'Charge: ' },
],
};
},
};
return Object.freeze(model);
}
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