diff --git a/fixed.js b/fixed.js index b1d671d..ec39bee 100644 --- a/fixed.js +++ b/fixed.js @@ -8,7 +8,8 @@ let inputRange = 4; let shift = 4; let base = 2 ** (bits - shift); -let reduction = 4; +//let reduction = 4; +let reduction = 0; let roundOffset = (2 ** (reduction - 1)) + 1; let entries = 2 ** (bits - reduction); let bytes = Math.ceil(bits / 8) * entries; diff --git a/sim.html b/sim.html index 61689cb..a260a0d 100644 --- a/sim.html +++ b/sim.html @@ -8,14 +8,28 @@

Mandelbrot fixed-point test

-

Float

- - -

Fixed-point imul

- - -

Fixed-point log

- + + + + + + + + + + + + + + +
FloatFixed-point imulFixed-point log
+ + + + + + +
diff --git a/sim.js b/sim.js index 4f819f0..1050860 100644 --- a/sim.js +++ b/sim.js @@ -1,9 +1,50 @@ import {toFixed, toFloat, mul} from './fixed.js'; + +function imul(a, b) { + return Math.imul(a, b) >> 12; +} + +function logmul(a, b) { + if ((a | b) == 0) { + return 0; + } + let neg = 0; + if (a < 0) { + a = -a; + neg++; + } + if (b < 0) { + b = -b; + neg++; + } + let product = mul(a, b); + if (neg == 1) { + product = -product; + } + return product; +} + +let four = toFixed(4); + let max = 256; let width = 256; let height = 256; -let zoom = 1; + +let zoom = 0; +let offsetX = 0; +let offsetY = 0; + +function scale() { + return 1 / (2 ** zoom); +} + +let cancelled = false; + +async function cancel() { + cancelled = true; + return await nap(100); +} let black = 0xff000000; let tricolor = [ @@ -17,49 +58,138 @@ palette[0] = black; for (let i = 0; i < 255; i++) { palette[i + 1] = tricolor[i % 3]; } -function nap() { - return new Promise((resolve) => setTimeout(() => resolve())); +function nap(ms=0) { + return new Promise((resolve) => setTimeout(() => resolve(), ms)); } +function attach(id, func) { + document.getElementById(id).addEventListener('click', (_event) => { + cancel().then(() => { + func(); + run(); + }); + }); +} + +attach('zoom-in', () => { + zoom++; +}); + +attach('zoom-out', () => { + if (zoom >= 1) { + zoom--; + } +}); + +attach('left', () => { + offsetX -= scale(); +}); + +attach('right', () => { + offsetX += scale(); +}); + +attach('up', () => { + offsetY -= scale(); +}); + +attach('down', () => { + offsetY += scale(); +}); + async function setup(id, iterfunc) { let canvas = document.getElementById(id); let ctx = canvas.getContext('2d'); let imageData = ctx.createImageData(width, height); let rgba = new Uint32Array(imageData.data.buffer); + + cancelled = false; for (let y = 0; y < height; y++) { - let cy = (y * 2 - height) / (height / 2); + let cy = scale() * (y * 2 - height) / (height / 2) + offsetY; for (let x = 0; x < width; x++) { - let cx = (x * 2 - width) / (width / 2); + let cx = scale() * (x * 2 - width) / (width / 2) + offsetX; let i = iterfunc(cx, cy); let color = palette[i]; rgba[y * width + x] = color; - rgba[(256 - y) * width + x] = color; - if (x % 16 == 15) { + if (x % 256 == 255) { ctx.putImageData(imageData, 0, 0); await nap(); + if (cancelled) { + return; + } } } } } -setup('float', (cx, cy) => { - let zx = 0; - let zy = 0; - let zx_2 = 0; - let zy_2 = 0; - let zx_zy = 0; - for (let i = 1; i < max; i++) { - zx = zx_2 - zy_2 + cx; - zy = zx_zy + zx_zy + cy; - zx_2 = zx * zx; - zy_2 = zy * zy; - zx_zy = zx * zy; - if (zx_2 >= 4 || zy_2 >= 4 || zx_2 + zy_2 >= 4) { - return i; +function run() { + setup('float', (cx, cy) => { + let zx = 0; + let zy = 0; + let zx_2 = 0; + let zy_2 = 0; + let zx_zy = 0; + for (let i = 1; i < max; i++) { + zx = zx_2 - zy_2 + cx; + zy = zx_zy + zx_zy + cy; + zx_2 = zx * zx; + zy_2 = zy * zy; + zx_zy = zx * zy; + if (zx_2 + zy_2 >= 4) { + return i; + } } - } - return 0; -}).then(() => { - console.log('done'); -}) \ No newline at end of file + return 0; + }).then(() => { + console.log('float done'); + }); + + setup('imul', (cx, cy) => { + cx = toFixed(cx); + cy = toFixed(cy); + let zx = 0; + let zy = 0; + let zx_2 = 0; + let zy_2 = 0; + let zx_zy = 0; + for (let i = 1; i < max; i++) { + zx = zx_2 - zy_2 + cx; + zy = zx_zy + zx_zy + cy; + zx_2 = imul(zx, zx); + zy_2 = imul(zy, zy); + zx_zy = imul(zx, zy); + if (zx_2 + zy_2 >= four) { + return i; + } + } + return 0; + }).then(() => { + console.log('imul done'); + }); + + setup('log', (cx, cy) => { + cx = toFixed(cx); + cy = toFixed(cy); + let zx = 0; + let zy = 0; + let zx_2 = 0; + let zy_2 = 0; + let zx_zy = 0; + for (let i = 1; i < max; i++) { + zx = zx_2 - zy_2 + cx; + zy = zx_zy + zx_zy + cy; + zx_2 = logmul(zx, zx); + zy_2 = logmul(zy, zy); + zx_zy = logmul(zx, zy); + if (zx_2 + zy_2 >= four) { + return i; + } + } + return 0; + }).then(() => { + console.log('log done'); + }); +} + +run(); \ No newline at end of file