diff --git a/d2layouts/d2cycle/layout.go b/d2layouts/d2cycle/layout.go index e8eeeba11..a2999b1d4 100644 --- a/d2layouts/d2cycle/layout.go +++ b/d2layouts/d2cycle/layout.go @@ -1,238 +1,261 @@ package d2cycle import ( - "context" - "math" + "context" + "math" - "oss.terrastruct.com/d2/d2graph" - "oss.terrastruct.com/d2/lib/geo" - "oss.terrastruct.com/d2/lib/label" - "oss.terrastruct.com/util-go/go2" + "oss.terrastruct.com/d2/d2graph" + "oss.terrastruct.com/d2/lib/geo" + "oss.terrastruct.com/d2/lib/label" + "oss.terrastruct.com/util-go/go2" ) const ( - MIN_RADIUS = 200 - PADDING = 20 - MIN_SEGMENT_LEN = 10 - ARC_STEPS = 30 - EPSILON = 1e-10 // Small value for floating point comparisons + MIN_RADIUS = 200 + PADDING = 20 + MIN_SEGMENT_LEN = 10 + ARC_STEPS = 30 + EPSILON = 1e-10 // Small value for floating point comparisons ) +// Layout computes node positions and generates curved edge routes. func Layout(ctx context.Context, g *d2graph.Graph, layout d2graph.LayoutGraph) error { - objects := g.Root.ChildrenArray - if len(objects) == 0 { - return nil - } + objects := g.Root.ChildrenArray + if len(objects) == 0 { + return nil + } - for _, obj := range g.Objects { - positionLabelsIcons(obj) - } + for _, obj := range g.Objects { + positionLabelsIcons(obj) + } - radius := calculateRadius(objects) - positionObjects(objects, radius) + radius := calculateRadius(objects) + positionObjects(objects, radius) - for _, edge := range g.Edges { - createPreciseCircularArc(edge) - } + for _, edge := range g.Edges { + createPreciseCircularArc(edge) + } - return nil + return nil } func calculateRadius(objects []*d2graph.Object) float64 { - numObjects := float64(len(objects)) - maxSize := 0.0 - for _, obj := range objects { - size := math.Max(obj.Box.Width, obj.Box.Height) - maxSize = math.Max(maxSize, size) - } - minRadius := (maxSize/2.0 + PADDING) / math.Sin(math.Pi/numObjects) - return math.Max(minRadius, MIN_RADIUS) + numObjects := float64(len(objects)) + maxSize := 0.0 + for _, obj := range objects { + size := math.Max(obj.Box.Width, obj.Box.Height) + maxSize = math.Max(maxSize, size) + } + minRadius := (maxSize/2.0 + PADDING) / math.Sin(math.Pi/numObjects) + return math.Max(minRadius, MIN_RADIUS) } func positionObjects(objects []*d2graph.Object, radius float64) { - numObjects := float64(len(objects)) - angleOffset := -math.Pi / 2 + numObjects := float64(len(objects)) + angleOffset := -math.Pi / 2 - for i, obj := range objects { - angle := angleOffset + (2*math.Pi*float64(i)/numObjects) - x := radius * math.Cos(angle) - y := radius * math.Sin(angle) + for i, obj := range objects { + angle := angleOffset + (2*math.Pi*float64(i)/numObjects) + x := radius * math.Cos(angle) + y := radius * math.Sin(angle) - obj.TopLeft = geo.NewPoint( - x-obj.Box.Width/2, - y-obj.Box.Height/2, - ) - } + obj.TopLeft = geo.NewPoint( + x-obj.Box.Width/2, + y-obj.Box.Height/2, + ) + } } +// createPreciseCircularArc computes a curved edge path that touches the node boundaries exactly. func createPreciseCircularArc(edge *d2graph.Edge) { - if edge.Src == nil || edge.Dst == nil { - return - } + if edge.Src == nil || edge.Dst == nil { + return + } - srcCenter := edge.Src.Center() - dstCenter := edge.Dst.Center() + srcCenter := edge.Src.Center() + dstCenter := edge.Dst.Center() - // Calculate angles in the circular layout - srcAngle := math.Atan2(srcCenter.Y, srcCenter.X) - dstAngle := math.Atan2(dstCenter.Y, dstCenter.X) - if dstAngle < srcAngle { - dstAngle += 2 * math.Pi - } + // Compute angles for the circular arc. + srcAngle := math.Atan2(srcCenter.Y, srcCenter.X) + dstAngle := math.Atan2(dstCenter.Y, dstCenter.X) + if dstAngle < srcAngle { + dstAngle += 2 * math.Pi + } - arcRadius := math.Hypot(srcCenter.X, srcCenter.Y) + arcRadius := math.Hypot(srcCenter.X, srcCenter.Y) - // Generate initial path points - path := make([]*geo.Point, 0, ARC_STEPS+1) - for i := 0; i <= ARC_STEPS; i++ { - t := float64(i) / float64(ARC_STEPS) - angle := srcAngle + t*(dstAngle-srcAngle) - x := arcRadius * math.Cos(angle) - y := arcRadius * math.Sin(angle) - path = append(path, geo.NewPoint(x, y)) - } + // Generate the initial arc path. + path := make([]*geo.Point, 0, ARC_STEPS+1) + for i := 0; i <= ARC_STEPS; i++ { + t := float64(i) / float64(ARC_STEPS) + angle := srcAngle + t*(dstAngle-srcAngle) + x := arcRadius * math.Cos(angle) + y := arcRadius * math.Sin(angle) + path = append(path, geo.NewPoint(x, y)) + } - // Find precise intersection points - srcIntersection := findPreciseBoxIntersection(edge.Src.Box, path[0], path[1]) - dstIntersection := findPreciseBoxIntersection(edge.Dst.Box, path[len(path)-1], path[len(path)-2]) + // Compute precise intersection points so the arrow touches the node boundaries. + // For the source, the segment goes from the center (inside) to the next point (outside). + srcIntersection := findPreciseBoxIntersection(edge.Src.Box, path[0], path[1]) + // For the destination, the segment goes from the center to the previous point (outside). + dstIntersection := findPreciseBoxIntersection(edge.Dst.Box, path[len(path)-1], path[len(path)-2]) - // Update path endpoints with precise intersections - path[0] = srcIntersection - path[len(path)-1] = dstIntersection + // Update the endpoints with the snapped intersection points. + path[0] = srcIntersection + path[len(path)-1] = dstIntersection - // Remove any points that might be inside the boxes - startIdx := 0 - endIdx := len(path) - 1 + // Trim intermediate points that still fall inside the boxes. + startIdx := 0 + endIdx := len(path) - 1 + for i := 1; i < len(path); i++ { + if !boxContains(edge.Src.Box, path[i]) { + startIdx = i - 1 + break + } + } + for i := len(path) - 2; i >= 0; i-- { + if !boxContains(edge.Dst.Box, path[i]) { + endIdx = i + 1 + break + } + } - for i := 1; i < len(path)-1; i++ { - if boxContains(edge.Src.Box, path[i]) { - startIdx = i - } - if boxContains(edge.Dst.Box, path[i]) { - endIdx = i - break - } - } - - edge.Route = path[startIdx:endIdx+1] - edge.IsCurve = true + edge.Route = path[startIdx : endIdx+1] + edge.IsCurve = true } +// findPreciseBoxIntersection returns the intersection point of the line (from p1 to p2) with the box boundary, +// snapped exactly to the nearest edge. func findPreciseBoxIntersection(box *geo.Box, p1, p2 *geo.Point) *geo.Point { - // Define box edges as line segments - edges := []geo.Segment{ - // Top edge - *geo.NewSegment( - geo.NewPoint(box.TopLeft.X, box.TopLeft.Y), - geo.NewPoint(box.TopLeft.X+box.Width, box.TopLeft.Y), - ), - // Right edge - *geo.NewSegment( - geo.NewPoint(box.TopLeft.X+box.Width, box.TopLeft.Y), - geo.NewPoint(box.TopLeft.X+box.Width, box.TopLeft.Y+box.Height), - ), - // Bottom edge - *geo.NewSegment( - geo.NewPoint(box.TopLeft.X, box.TopLeft.Y+box.Height), - geo.NewPoint(box.TopLeft.X+box.Width, box.TopLeft.Y+box.Height), - ), - // Left edge - *geo.NewSegment( - geo.NewPoint(box.TopLeft.X, box.TopLeft.Y), - geo.NewPoint(box.TopLeft.X, box.TopLeft.Y+box.Height), - ), - } + // Define the four box edges. + edges := []geo.Segment{ + *geo.NewSegment( + geo.NewPoint(box.TopLeft.X, box.TopLeft.Y), + geo.NewPoint(box.TopLeft.X+box.Width, box.TopLeft.Y), + ), // Top + *geo.NewSegment( + geo.NewPoint(box.TopLeft.X+box.Width, box.TopLeft.Y), + geo.NewPoint(box.TopLeft.X+box.Width, box.TopLeft.Y+box.Height), + ), // Right + *geo.NewSegment( + geo.NewPoint(box.TopLeft.X, box.TopLeft.Y+box.Height), + geo.NewPoint(box.TopLeft.X+box.Width, box.TopLeft.Y+box.Height), + ), // Bottom + *geo.NewSegment( + geo.NewPoint(box.TopLeft.X, box.TopLeft.Y), + geo.NewPoint(box.TopLeft.X, box.TopLeft.Y+box.Height), + ), // Left + } - // Line segment from p1 to p2 - line := *geo.NewSegment(p1, p2) + // Construct the line from p1 (inside) to p2 (outside). + line := *geo.NewSegment(p1, p2) + var closestIntersection *geo.Point + minDist := math.MaxFloat64 - // Find the intersection point closest to p1 - var closestIntersection *geo.Point - minDist := math.MaxFloat64 + // Find the intersection among the four edges that is closest to p1. + for _, seg := range edges { + if intersection := findSegmentIntersection(line, seg); intersection != nil { + dist := math.Hypot(intersection.X-p1.X, intersection.Y-p1.Y) + if dist < minDist { + minDist = dist + closestIntersection = intersection + } + } + } - for _, edge := range edges { - if intersection := findSegmentIntersection(line, edge); intersection != nil { - dist := math.Hypot( - intersection.X-p1.X, - intersection.Y-p1.Y, - ) - if dist < minDist { - minDist = dist - closestIntersection = intersection - } - } - } - - if closestIntersection != nil { - return closestIntersection - } - return p1 + if closestIntersection != nil { + return snapToBoundary(box, closestIntersection) + } + return p1 } +// findSegmentIntersection computes the intersection between two line segments s1 and s2 using their parametric form. func findSegmentIntersection(s1, s2 geo.Segment) *geo.Point { - // Calculate the intersection of two line segments using parametric equations - x1, y1 := s1.Start.X, s1.Start.Y - x2, y2 := s1.End.X, s1.End.Y - x3, y3 := s2.Start.X, s2.Start.Y - x4, y4 := s2.End.X, s2.End.Y + x1, y1 := s1.Start.X, s1.Start.Y + x2, y2 := s1.End.X, s1.End.Y + x3, y3 := s2.Start.X, s2.Start.Y + x4, y4 := s2.End.X, s2.End.Y - denominator := (x1-x2)*(y3-y4) - (y1-y2)*(x3-x4) - if math.Abs(denominator) < EPSILON { - return nil - } + denom := (x1-x2)*(y3-y4) - (y1-y2)*(x3-x4) + if math.Abs(denom) < EPSILON { + return nil + } - t := ((x1-x3)*(y3-y4) - (y1-y3)*(x3-x4)) / denominator - u := -((x1-x2)*(y1-y3) - (y1-y2)*(x1-x3)) / denominator + t := ((x1-x3)*(y3-y4) - (y1-y3)*(x3-x4)) / denom + u := -((x1-x2)*(y1-y3) - (y1-y2)*(x1-x3)) / denom - if t >= 0 && t <= 1 && u >= 0 && u <= 1 { - x := x1 + t*(x2-x1) - y := y1 + t*(y2-y1) - return geo.NewPoint(x, y) - } - - return nil + if t >= 0 && t <= 1 && u >= 0 && u <= 1 { + x := x1 + t*(x2-x1) + y := y1 + t*(y2-y1) + return geo.NewPoint(x, y) + } + return nil } +// snapToBoundary adjusts point p so that it lies exactly on the nearest boundary of box. +func snapToBoundary(box *geo.Box, p *geo.Point) *geo.Point { + left := box.TopLeft.X + right := box.TopLeft.X + box.Width + top := box.TopLeft.Y + bottom := box.TopLeft.Y + box.Height + + dLeft := math.Abs(p.X - left) + dRight := math.Abs(p.X - right) + dTop := math.Abs(p.Y - top) + dBottom := math.Abs(p.Y - bottom) + + if dLeft < dRight && dLeft < dTop && dLeft < dBottom { + return geo.NewPoint(left, p.Y) + } else if dRight < dLeft && dRight < dTop && dRight < dBottom { + return geo.NewPoint(right, p.Y) + } else if dTop < dBottom { + return geo.NewPoint(p.X, top) + } else { + return geo.NewPoint(p.X, bottom) + } +} + +// boxContains returns true if point p is inside the box (using EPSILON for floating point tolerance). func boxContains(b *geo.Box, p *geo.Point) bool { - return p.X >= b.TopLeft.X-EPSILON && - p.X <= b.TopLeft.X+b.Width+EPSILON && - p.Y >= b.TopLeft.Y-EPSILON && - p.Y <= b.TopLeft.Y+b.Height+EPSILON + return p.X >= b.TopLeft.X-EPSILON && + p.X <= b.TopLeft.X+b.Width+EPSILON && + p.Y >= b.TopLeft.Y-EPSILON && + p.Y <= b.TopLeft.Y+b.Height+EPSILON } func positionLabelsIcons(obj *d2graph.Object) { - if obj.Icon != nil && obj.IconPosition == nil { - if len(obj.ChildrenArray) > 0 { - obj.IconPosition = go2.Pointer(label.OutsideTopLeft.String()) - if obj.LabelPosition == nil { - obj.LabelPosition = go2.Pointer(label.OutsideTopRight.String()) - return - } - } else if obj.SQLTable != nil || obj.Class != nil || obj.Language != "" { - obj.IconPosition = go2.Pointer(label.OutsideTopLeft.String()) - } else { - obj.IconPosition = go2.Pointer(label.InsideMiddleCenter.String()) - } - } + if obj.Icon != nil && obj.IconPosition == nil { + if len(obj.ChildrenArray) > 0 { + obj.IconPosition = go2.Pointer(label.OutsideTopLeft.String()) + if obj.LabelPosition == nil { + obj.LabelPosition = go2.Pointer(label.OutsideTopRight.String()) + return + } + } else if obj.SQLTable != nil || obj.Class != nil || obj.Language != "" { + obj.IconPosition = go2.Pointer(label.OutsideTopLeft.String()) + } else { + obj.IconPosition = go2.Pointer(label.InsideMiddleCenter.String()) + } + } - if obj.HasLabel() && obj.LabelPosition == nil { - if len(obj.ChildrenArray) > 0 { - obj.LabelPosition = go2.Pointer(label.OutsideTopCenter.String()) - } else if obj.HasOutsideBottomLabel() { - obj.LabelPosition = go2.Pointer(label.OutsideBottomCenter.String()) - } else if obj.Icon != nil { - obj.LabelPosition = go2.Pointer(label.InsideTopCenter.String()) - } else { - obj.LabelPosition = go2.Pointer(label.InsideMiddleCenter.String()) - } + if obj.HasLabel() && obj.LabelPosition == nil { + if len(obj.ChildrenArray) > 0 { + obj.LabelPosition = go2.Pointer(label.OutsideTopCenter.String()) + } else if obj.HasOutsideBottomLabel() { + obj.LabelPosition = go2.Pointer(label.OutsideBottomCenter.String()) + } else if obj.Icon != nil { + obj.LabelPosition = go2.Pointer(label.InsideTopCenter.String()) + } else { + obj.LabelPosition = go2.Pointer(label.InsideMiddleCenter.String()) + } - if float64(obj.LabelDimensions.Width) > obj.Width || - float64(obj.LabelDimensions.Height) > obj.Height { - if len(obj.ChildrenArray) > 0 { - obj.LabelPosition = go2.Pointer(label.OutsideTopCenter.String()) - } else { - obj.LabelPosition = go2.Pointer(label.OutsideBottomCenter.String()) - } - } - } -} \ No newline at end of file + if float64(obj.LabelDimensions.Width) > obj.Width || + float64(obj.LabelDimensions.Height) > obj.Height { + if len(obj.ChildrenArray) > 0 { + obj.LabelPosition = go2.Pointer(label.OutsideTopCenter.String()) + } else { + obj.LabelPosition = go2.Pointer(label.OutsideBottomCenter.String()) + } + } + } +}