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/**
* This file is a factory for DOM UI elements.
*/
/**
* Returns a settings container that includes a section and a heading.
*/
export function settingsContainer({id, label, level=2}) {
const container = document.createElement('section');
container.id = id;
container.innerHTML = `<h${level}>${label}</h${level}>`;
return container;
};
/**
* Returns a slider that includes a label, and can optionally be set to
* "shift" to a different step. (eg. we use this for π mode, where frequency
* and amplitude are mapped to π/8 increments.
*/
export function slider({
id,
min,
max,
step,
shiftStep,
get,
set,
label = '',
className
}) {
const sliderContainer = document.createElement('section');
sliderContainer.classList.add('slider');
sliderContainer.classList.add(className);
const labelElement = document.createElement('label');
labelElement.setAttribute('for', id);
labelElement.innerHTML = label;
const slider = document.createElement('input');
slider.id = id;
slider.type = 'range';
slider.min = min;
slider.max = max;
slider.step = step;
slider.value = get().toString();
if (shiftStep) {
document.addEventListener('keydown', function(event) {
if (event.shiftKey) {
slider.classList.add('shifted');
slider.step = shiftStep;
}
});
document.addEventListener('keyup', function(event) {
if (event.key === 'Shift') {
slider.classList.remove('shifted');
slider.step = step;
}
});
document.addEventListener('touchstart', function(event) {
if (event.touches.length == 3) {
if (slider.classList.contains('shifted')) {
slider.classList.remove('shifted');
slider.step = step;
} else {
slider.classList.add('shifted');
slider.step = shiftStep;
}
}
});
}
slider.addEventListener('input', () => set(slider.value));
sliderContainer.appendChild(labelElement);
sliderContainer.appendChild(slider);
return sliderContainer;
}
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