Run results for: Offscreen canvas vs cached Path2D vs no cache

Run details:

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.15; rv:138.0) Gecko/20100101 Firefox/138.0

Browser: Firefox 138

Operating system: Mac OS X 10.15

Device Platform: Desktop

Date tested: one year ago

Create instances of Path2D

46K/s

Render directly with ctx.fillRect()

18K/s

Render Path2D

17K/s

Render offscreen canvases

12K/s

Create instances of offscreen canvas

580/s

View exact numbers

Test name	Executions per second
✓ Create instances of Path2D	46,229 Ops/sec
Render directly with ctx.fillRect()	17,776 Ops/sec
Render Path2D	17,494 Ops/sec
Render offscreen canvases	12,318 Ops/sec
Create instances of offscreen canvas	580 Ops/sec

HTML Preparation code:

<canvas id="test-canvas"></canvas>

Script Preparation code:

const COUNT = 100

const offscreens = new Array(COUNT)
for (let i=0; i<COUNT; i++) {
  const canvas = document.createElement('canvas')
  canvas.width = 100
  canvas.height = 50
  const ctx = canvas.getContext('2d')
  ctx.fillStyle = "red"
  ctx.fillRect(0, 0, 100, 50)
  offscreens[i] = canvas
}

const path2ds = new Array(COUNT)
for (let i=0; i<COUNT; i++) {
  const path2d = new Path2D()
  path2d.rect(0, 0, 100, 50)
  path2ds[i] = path2d
}

const canvas = document.getElementById('test-canvas')
const ctx = canvas.getContext('2d')

Tests:

Create instances of offscreen canvas
const results = new Array(COUNT) for (let i=0; i<COUNT; i++) { const canvas = document.createElement('canvas') canvas.width = 100 canvas.height = 50 const ctx = canvas.getContext('2d') ctx.fillStyle = "red" ctx.fillRect(0, 0, 100, 50) results[i] = canvas }
Create instances of Path2D
const results = new Array(COUNT) for (let i=0; i<COUNT; i++) { const path2d = new Path2D() path2d.rect(0, 0, 100, 50) results[i] = path2d }
Render offscreen canvases
for (let i=0; i<COUNT; i++) { ctx.drawImage(offscreens[i], 0, 0, 100, 50) }
Render Path2D
for (let i=0; i<COUNT; i++) { ctx.fillStyle = "red" ctx.fill(path2ds[i]) }
Render directly with ctx.fillRect()
for (let i=0; i<COUNT; i++) { ctx.fillStyle = "red" ctx.fillRect(0, 0, 100, 50) }