select circo based on graph density

Author: IvanGoncharov

src/components/GraphViewport.tsx

@@ -144,6 +144,7 @@ export default class GraphViewport extends Component<
           rawError instanceof Error
             ? rawError
             : new Error('Unknown error: ' + String(rawError));
+        console.error(error);
         this.setState(() => {
           throw error;
         });

src/graph/dot.ts

@@ -128,11 +128,14 @@ export function getDot(typeGraph: TypeGraph): Graph {
     });
   }
 
+  const graphDensity = edges.length / (nodes.length * (nodes.length - 1));
   return {
     directed: true,
     graphAttributes: {
       rankdir: 'LR',
       ranksep: 2.0,
+      layout:
+        typeGraph.rootType == null && graphDensity > 0.4 ? 'circo' : 'dot',
     },
     nodeAttributes: {
       fontsize: '16',

src/graph/svg-renderer.ts

@@ -14,7 +14,8 @@ export async function renderSvg(typeGraph: TypeGraph) {
   const rawSVG = await vizWorker.render({
     input: dot,
     options: {
-      engine: typeGraph.rootType == null ? 'circo' : 'dot',
+      // @ts-expect-error  FIXME should be fixed in dotviz
+      engine: dot.graphAttributes.layout,
       format: 'svg',
     },
   });