| <!DOCTYPE html> |
| <link rel="help" href="https://html.spec.whatwg.org/#dom-offscreencanvas"> |
| <canvas id="c1" width="100" height="100"></canvas> |
| <canvas id="c2" width="100" height="100"></canvas> |
| <canvas id="c3" width="100" height="100"></canvas> |
| <canvas id="c4" width="100" height="100"></canvas> |
| <script> |
| const offscreenCanvas = new OffscreenCanvas(100, 100); |
| const gl = offscreenCanvas.getContext("webgl"); |
| |
| gl.clearColor(1, 0, 0, 1); |
| gl.clear(gl.COLOR_BUFFER_BIT); |
| |
| const c1 = document.getElementById("c1"); |
| const bitmapContext1 = c1.getContext("bitmaprenderer"); |
| bitmapContext1.transferFromImageBitmap(offscreenCanvas.transferToImageBitmap()); |
| |
| gl.clearColor(0, 1, 0, 1); |
| gl.clear(gl.COLOR_BUFFER_BIT); |
| |
| const c2 = document.getElementById("c2"); |
| const bitmapContext2 = c2.getContext("bitmaprenderer"); |
| bitmapContext2.transferFromImageBitmap(offscreenCanvas.transferToImageBitmap()); |
| |
| gl.clearColor(0, 0, 1, 1); |
| gl.clear(gl.COLOR_BUFFER_BIT); |
| |
| const c3 = document.getElementById("c3"); |
| const bitmapContext3 = c3.getContext("bitmaprenderer"); |
| bitmapContext3.transferFromImageBitmap(offscreenCanvas.transferToImageBitmap()); |
| |
| const c4 = document.getElementById("c4"); |
| const bitmapContext4 = c4.getContext("bitmaprenderer"); |
| bitmapContext4.transferFromImageBitmap(offscreenCanvas.transferToImageBitmap()); |
| </script> |