export function now(): number {

return performance.now();

}

export function expectContents(actual: any, exp: any) {

const size = exp.byteLength;

if (actual.byteLength !== size) {

return 'size mismatch';

}

const lines = [];

let failedPixels = 0;

for (let i = 0; i < size; ++i) {

if (actual[i] !== exp[i]) {

if (failedPixels > 4) {

lines.push('... and more');

break;

}

failedPixels++;

lines.push(`at [${i}], expected ${exp[i]}, got ${actual[i]}`);

}

} // TODO: Could make a more convenient message, which could look like e.g.:

//

// Starting at offset 48,

// got 22222222 ABCDABCD 99999999

// but expected 22222222 55555555 99999999

//

// or

//

// Starting at offset 0,

// got 00000000 00000000 00000000 00000000 (... more)

// but expected 00FF00FF 00FF00FF 00FF00FF 00FF00FF (... more)

//

// Or, maybe these diffs aren't actually very useful (given we have the prints

// just above here), and we should remove them. More important will be logging

// of texture data in a visual format.

if (size <= 256 && failedPixels > 0) {

const expHex =

Array.from(exp).map(x => x.toString().padStart(2, '0')).join('');

const actHex =

Array.from(actual).map(x => x.toString().padStart(2, '0')).join('');

lines.push('EXPECT: ' + expHex);

lines.push('ACTUAL: ' + actHex);

}

if (failedPixels) {

return lines.join('\n');

}

return undefined;

}