Christian Gudrian<p><a href="https://social.tchncs.de/tags/Sketchpad" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>Sketchpad</span></a> – An interactive vector-based drawing program with pen input and constraint solver.</p><p>From the early 1960s. 🤯</p><p><a href="https://www.youtube.com/watch?v=6orsmFndx_o" rel="nofollow noopener" translate="no" target="_blank"><span class="invisible">https://www.</span><span class="">youtube.com/watch?v=6orsmFndx_o</span><span class="invisible"></span></a></p>