package main import ( "sort" "github.com/mediocregopher/ginger/gg" "github.com/mediocregopher/ginger/gim/constraint" "github.com/mediocregopher/ginger/gim/geo" "github.com/mediocregopher/ginger/gim/terminal" ) // "Solves" vertex position by detemining relative positions of vertices in // primary and secondary directions (independently), with relative positions // being described by "levels", where multiple vertices can occupy one level. // // Primary determines relative position in the primary direction by trying // to place vertices before their outs and after their ins. // // Secondary determines relative position in the secondary direction by // trying to place vertices relative to vertices they share an edge with in // the order that the edges appear on the shared node. func posSolve(g *gg.Graph) [][]*gg.Vertex { primEng := constraint.NewEngine() secEng := constraint.NewEngine() strM := g.ByID() for _, v := range strM { var prevIn *gg.Vertex for _, e := range v.In { primEng.AddConstraint(constraint.Constraint{ Elem: e.From.ID, LT: v.ID, }) if prevIn != nil { secEng.AddConstraint(constraint.Constraint{ Elem: prevIn.ID, LT: e.From.ID, }) } prevIn = e.From } var prevOut *gg.Vertex for _, e := range v.Out { if prevOut == nil { continue } secEng.AddConstraint(constraint.Constraint{ Elem: prevOut.ID, LT: e.To.ID, }) prevOut = e.To } } prim := primEng.Solve() sec := secEng.Solve() // determine maximum primary level var maxPrim int for _, lvl := range prim { if lvl > maxPrim { maxPrim = lvl } } outStr := make([][]string, maxPrim+1) for v, lvl := range prim { outStr[lvl] = append(outStr[lvl], v) } // sort each primary level for _, vv := range outStr { sort.Slice(vv, func(i, j int) bool { return sec[vv[i]] < sec[vv[j]] }) } // convert to vertices out := make([][]*gg.Vertex, len(outStr)) for i, vv := range outStr { out[i] = make([]*gg.Vertex, len(outStr[i])) for j, v := range vv { out[i][j] = strM[v] } } return out } // mutates the boxes to be centered around the given point, keeping their // relative position to each other func centerBoxes(boxes []*box, around geo.XY) { var graphRect geo.Rect for _, b := range boxes { graphRect = graphRect.Union(b.rect()) } graphMid := graphRect.Center(rounder) delta := around.Sub(graphMid) for _, b := range boxes { b.topLeft = b.topLeft.Add(delta) } } type view struct { g *gg.Graph primFlowDir, secFlowDir geo.XY start gg.Value center geo.XY } func (view *view) draw(term *terminal.Terminal) { relPos := posSolve(view.g) // create boxes var boxes []*box boxesM := map[*box]*gg.Vertex{} boxesMr := map[*gg.Vertex]*box{} const ( primPadding = 5 secPadding = 3 ) var primPos int for _, vv := range relPos { var primBoxes []*box // boxes on just this level var maxPrim int var secPos int for _, v := range vv { primVec := view.primFlowDir.Scale(primPos) secVec := view.secFlowDir.Scale(secPos) b := boxFromVertex(v, view.primFlowDir) b.topLeft = primVec.Add(secVec) boxes = append(boxes, &b) primBoxes = append(primBoxes, &b) boxesM[&b] = v boxesMr[v] = &b bSize := b.rect().Size primBoxLen := bSize.Mul(view.primFlowDir).Len(rounder) secBoxLen := bSize.Mul(view.secFlowDir).Len(rounder) if primBoxLen > maxPrim { maxPrim = primBoxLen } secPos += secBoxLen + secPadding } centerBoxes(primBoxes, view.primFlowDir.Scale(primPos)) primPos += maxPrim + primPadding } // create lines var lines []line for _, b := range boxes { v := boxesM[b] for _, e := range v.In { bFrom := boxesMr[e.From] lines = append(lines, line{bFrom, b}) } } // translate all boxes so the graph is centered around v.center centerBoxes(boxes, view.center) // actually draw the boxes and lines for _, b := range boxes { b.draw(term) } for _, line := range lines { line.draw(term, view.primFlowDir) } }