roundedBox.js

// Using p5.js
function roundedBox(length, width, height, radius) {
  // Draw walls (three orthogonal boxes)
  box(length, width - radius, height - radius);
  box(length - radius, width, height - radius);
  box(length - radius, width - radius, height);

  // Draw 8 corner spheres
  for (let xSign = -1; xSign <= 1; xSign += 2) {
    for (let ySign = -1; ySign <= 1; ySign += 2) {
      for (let zSign = -1; zSign <= 1; zSign += 2) {
        push();
        translate(
          xSign * (length - radius)/2,
          ySign * (width - radius)/2,
          zSign * (height - radius)/2
        );
        sphere(radius/2, 10, 10);
        pop();
      }
    }
  }

  // Draw 12 edge cylinders
  // X-axis aligned edges
  [-1, 1].forEach(ySign => {
    [-1, 1].forEach(zSign => {
      push();
      translate(0, ySign * (width - radius)/2, zSign * (height - radius)/2);
      rotateZ(-HALF_PI);
      cylinder(radius/2, length - radius, 10, 1, false, false);
      pop();
    });
  });

  // Y-axis aligned edges
  [-1, 1].forEach(xSign => {
    [-1, 1].forEach(zSign => {
      push();
      translate(xSign * (length - radius)/2, 0, zSign * (height - radius)/2);
      cylinder(radius/2, width - radius, 10, 1, false, false);
      pop();
    });
  });

  // Z-axis aligned edges
  [-1, 1].forEach(xSign => {
    [-1, 1].forEach(ySign => {
      push();
      translate(xSign * (length - radius)/2, ySign * (width - radius)/2, 0);
      rotateX(HALF_PI);
      cylinder(radius/2, height - radius, 10, 1, false, false);
      pop();
    });
  });
}