Published
Edited
Mar 20, 2021
6 stars
function create3DFrame (frame, index) {
const { width: w, height: h } = stageCanvas
let canvas = stageCanvas
let ctx = stageCtx
// this isn't performant at all but frames are cool
if (viewDebugFrames) {
canvas = document.createElement('canvas')
canvas.width = w
canvas.height = h
frameDebugContainer.appendChild(canvas)
ctx = canvas.getContext('2d')
}
ctx.clearRect(0, 0, w, h)
// center the image in the texture
ctx.putImageData(frame.data, (w - imgDims.width) / 2, (h - imgDims.height) / 2)
const texture = new THREE.CanvasTexture(canvas)
const material = new THREE.ShaderMaterial({
vertexShader,
fragmentShader,
uniforms: {
tex: { type: "t", value: texture }
},
side: THREE.DoubleSide,
transparent: true
// blending: THREE.AdditiveBlending
})
const geometry = new THREE.PlaneGeometry(w, h, 2)
const mesh = new THREE.Mesh(geometry, material)
mesh.position.z = index - 30
return mesh
}
function processGif (img, arrayBuffer) {
let gif = SuperGIF({ gif: img, auto_play: 1 })
gif.load_raw(arrayBuffer, () => {
for (let i = 0, frames = gif.get_length(); i < frames; i++) {
const frame = gif.get_frame(i)
const makeFrame = () => {
frameNum.innerText = i
container3D.add(create3DFrame(frame, i))
}
// FIXME need to clear timeouts on Observable re-render
setTimeout(makeFrame, 250 * i)
}
})
}
async function loadGifArrayBuffer (url) {
try {
const res = await fetch(url)
const buf = await res.arrayBuffer()
return new Uint8Array(buf)
} catch (e) {
console.error(e)
return new Uint8Array()
}
}
go = {
loadGifArrayBuffer(gifURL)
.then(arr => processGif($img, arr))
.catch(e => console.error(e))
}
// dimensions for the original data image
imgDims = ({ width: 61, height: 73 })
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