Class BeetPxUtils

This function is meant to be used in a last branch of if - else if - … - else chain or in default of switch - case - case - …. Let's imagine there is a union type of which we check all possible cases. Someday we add one more type to the union, but we forget to extend our switch by that one more case. Thanks to assertUnreachable(theValueOfThatUnionType) the TypeScript checker will inform us about such mistake.

Returns the middle number out of given three numbers. Useful for keeping a given property within specified bounds.

Example

clamp(minSpeed, currentSpeed, maxSpeed);
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Similar to BeetPxDraw.text, but with a second color specified, to be used as an outline.

A simple helper which returns what it takes, without any changes.

Example

const doTheFancyTransformation = (x: value) => ...;
const fn = makeItFancy ? doTheFancyTransformation : BeetPxUtils.identity;
const newX = fn(x);
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Picks a number between a and b which is in a "distance" between them as specified by t. Specifically: lerp(a,b,0) === a and lerp(a,b,1) === b.

With opts: { clamp: true }, the resulting value cannot is always within bounds of a and b, even if t is below 0 or above 1.

A modulo operation – in contrary to native JavaScript's %, this one returns results from [0, n) range (positive values only).

Example

if ($.wasButtonJustPressed("up")) {
  selected = BeetPxUtils.mod(selected - 1);
}
const menuItem = menuItems[selected];
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A simple helper which does nothing.

Example

const doTheFancyThing = () => ...;
const fn = makeItFancy ? doTheFancyThing : BeetPxUtils.noop;
fn();
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Generates a list of XY to add to a given coordinate in order to get all offsets by 1 pixel in 4 directions. Useful e.g. for iterating over adjacent tiles on the game map.

Generates a list of XY to add to a given coordinate in order to get all offsets by 1 pixel in 8 directions. Useful e.g. for iterating over adjacent tiles on the game map, including diagonals.

Picks a random element from a given array.

Generates an array from 0 to n-1. Useful when we want to do a thing N times.

Example

BeetPxUtils.range(10).forEach(i => {
  BeetPxDraw.rect($v(1, 1 + i * 8), $v(40, 7), $rgb_red);
});
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Takes an array an returns a new one, in which each element is repeated given amount of times.

Example

BeetPxUtils.repeatEachElement(3, ["a", "b"]);
// The above produces `["a", "a", "a", "b", "b", "b"]`.
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To be used as a value, e.g. in definedValue: maybeUndefined() ?? throwError("…").

Example

function getValue(): number | null {
  // ...
}
const value = getValue() ?? throwError("Failed to get the value");
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