function *draw() {
let gl = regl._gl;
setupDefault(() => {
gl.enable(gl.SCISSOR_TEST);
gl.scissor(10, 10, 100, 100);
regl.clear({color: [0., 1., 0, 1.0], depth: 1});
gl.scissor(100, 100, 100, 100);
gl.viewport(100, 100, 100, 100);
drawGradient();
gl.scissor(200, 200, 100, 100);
gl.viewport(200, 200, 100, 100);
drawGradient();
});
yield regl.container
}