peabrainiac.github.io/GifScripter Save script Load script Output: Run ▶
Gif Scripter [experimental]

A simple gif scripting tool, to create gif animations programmatically.
const TOTAL_FRAMES = 72; const WIDTH = 480; const HEIGHT = 360; const ZOOM = 75; const ITERATIONS = 30; var frame = 0; var imgData = GifWriter.createImageData(WIDTH,HEIGHT); computeNextFrame(); function computeNextFrame(){ if (frame<TOTAL_FRAMES){ var px,py,cx,cy,x,y,x2,y2,i,c,r,g,b,pi; var rx = Math.cos(2*Math.PI*frame/TOTAL_FRAMES); var ry = Math.sin(2*Math.PI*frame/TOTAL_FRAMES); for (px=0;px<WIDTH;px++){ for (py=0;py<HEIGHT;py++){ cx = (px-WIDTH/2)/ZOOM; cy = (py-HEIGHT/2)/ZOOM; x = 0; y = 0; for (i=0;i<ITERATIONS&&x*x+y*y<4;i++){ x2 = x*x-y*y; y2 = 2*x*y; x = Math.abs(x2*rx-y2*ry+cx); y = Math.abs(y2*rx+x2*ry+cy); } c = (i<ITERATIONS)?Utils.hslToRgb(i/(5*ITERATIONS),0.75,i/ITERATIONS):[0,0,0]; pi = (px+py*WIDTH)*4; imgData.data[pi] = c[0]*255; imgData.data[pi+1] = c[1]*255; imgData.data[pi+2] = c[2]*255; imgData.data[pi+3] = 255; } } frame++; GifWriter.addFrame(imgData).then(computeNextFrame); }else{ GifWriter.finish(); } }