Function shapeIndexDebugString

s2/textformat_test.go:332–395

shapeIndexDebugString outputs the contents of this ShapeIndex in debug format. The index may contain Shapes of any type. Shapes are reordered if necessary so that all point geometry (shapes of dimension 0) are first, followed by all polyline geometry, followed by all polygon geometry.

(index *ShapeIndex, roundtripPrecision bool)

// if necessary so that all point geometry (shapes of dimension 0) are first,
// followed by all polyline geometry, followed by all polygon geometry.
func shapeIndexDebugString(index *ShapeIndex, roundtripPrecision bool) string {
	var buf bytes.Buffer

	for dim := 0; dim <= 2; dim++ {
		if dim > 0 {
			buf.WriteByte('#')
		}

		var count int

		// Use shapes ordered by id rather than ranging over the
		// index.shapes map to ensure that the ordering of shapes in the
		// generated string matches the C++ generated strings.
		for i := int32(0); i < index.nextID; i++ {
			shape := index.Shape(i)
			// Only use shapes that are still in the index and at the
			// current geometry level we are outputting.
			if shape == nil || shape.Dimension() != dim {
				continue
			}
			if count > 0 {
				buf.WriteString(" | ")
			} else {
				if dim > 0 {
					buf.WriteString(" ")
				} else {
					buf.WriteString("")
				}
			}

			for c := 0; c < shape.NumChains(); c++ {
				if c > 0 {
					if dim == 2 {
						buf.WriteString("; ")
					} else {
						buf.WriteString(" | ")
					}
				}
				chain := shape.Chain(c)
				if chain.Length == 0 {
					buf.WriteString("full")
				} else {
					writePoint(&buf, shape.Edge(chain.Start).V0, roundtripPrecision)
				}
				limit := chain.Start + chain.Length
				if dim != 1 {
					limit--
				}

				for e := chain.Start; e < limit; e++ {
					buf.WriteString(", ")
					writePoint(&buf, shape.Edge(e).V1, roundtripPrecision)
				}
				count++
			}
		}

		if dim == 1 || (dim == 0 && count > 0) {