Graphviz 工具

https://www.gravizo.com

http://graphviz.it/#/gallery/trapeziumlr.gv

http://magjac.com/graphviz-visual-editor/

https://github.com/dreampuf/GraphvizOnline/

https://github.com/mdaines/viz.js/wiki/Usage

https://edotor.net/

免费的 https://quickchart.io/documentation/graphviz-api/

http://dahlström.net/svg/html/get-embedded-svg-document-script.html

http://dreampuf.github.io/GraphvizOnline/ 自带输出，支持较多引擎，且 png 格式的较清晰，和 vscode 插件功能差不多

https://sketchviz.com/ 手绘风格，