lass="label"><input type="range" class="slider" min="0" max="20" value="10" step="1" id="range_gravity"
        onchange="SetGravity(this.value);">
        <span>gravity</span></label>
    </div>
    <div class="emscripten" style="padding: 5px;">
      <label class="label"><input type="range" class="slider" min="0" max="1" value="0.2" step="0.01" id="range_sigma"
        onchange="SetSigma(this.value);">
        <span>surface tension</span></label>
    </div>
    <div class="emscripten" style="padding: 5px;