func ReadNormals(fileName string) []Vector {
file, err := os.Open(fileName)
common.Check(err)
defer file.Close()
scanner := bufio.NewScanner(file)
scanner.Split(bufio.ScanWords)
var normals []Vector
for scanner.Scan() {
x, err := strconv.ParseFloat(scanner.Text(), 64)
common.Check(err)
scanner.Scan()
y, err := strconv.ParseFloat(scanner.Text(), 64)
common.Check(err)
scanner.Scan()
z, err := strconv.ParseFloat(scanner.Text(), 64)
common.Check(err)
normals = append(normals, Vector{x, y, z})
}
common.Check(scanner.Err())
return normals
}
func NewKdTree(fileName string, mesh *TriangleMesh) *KdTree {
file, err := os.Open(fileName)
common.Check(err)
defer file.Close()
reader := bufio.NewReader(file)
var nodesCount int32
err = binary.Read(reader, binary.LittleEndian, &nodesCount)
common.Check(err)
nodes := make([]node, nodesCount)
err = binary.Read(reader, binary.LittleEndian, &nodes)
common.Check(err)
var triangleIndicesCount int32
err = binary.Read(reader, binary.LittleEndian, &triangleIndicesCount)
common.Check(err)
triangleIndices := make([]int32, triangleIndicesCount)
err = binary.Read(reader, binary.LittleEndian, &triangleIndices)
common.Check(err)
return &KdTree{
nodes: nodes,
triangleIndices: triangleIndices,
mesh: mesh,
meshBounds: NewBBox64FromBBox32(mesh.GetBounds()),
}
}
func ReadNumbersFromFile(fileName string) []int32 {
file, err := os.Open(fileName)
common.Check(err)
defer file.Close()
reader := bufio.NewReader(file)
var numbersCount int32
err = binary.Read(reader, binary.LittleEndian, &numbersCount)
common.Check(err)
numbers := make([]int32, numbersCount)
err = binary.Read(reader, binary.LittleEndian, &numbers)
common.Check(err)
return numbers
}
func (kdTree *KdTree) SaveToFile(fileName string) {
file, err := os.Create(fileName)
common.Check(err)
defer file.Close()
writer := bufio.NewWriter(file)
nodesCount := int32(len(kdTree.nodes))
err = binary.Write(writer, binary.LittleEndian, nodesCount)
common.Check(err)
err = binary.Write(writer, binary.LittleEndian, kdTree.nodes)
common.Check(err)
triangleIndicesCount := int32(len(kdTree.triangleIndices))
err = binary.Write(writer, binary.LittleEndian, triangleIndicesCount)
common.Check(err)
err = binary.Write(writer, binary.LittleEndian, kdTree.triangleIndices)
common.Check(err)
err = writer.Flush()
common.Check(err)
}
func LoadTriangleMesh(fileName string) *TriangleMesh {
const (
headerSize = 80
facetSize = 50
maxVerticesCount = math.MaxInt32
maxTrianglesCount = math.MaxInt32
)
file, err := os.Open(fileName)
common.Check(err)
defer file.Close()
// get file size
stat, err := file.Stat()
common.Check(err)
fileSize := stat.Size()
// read file content
fileContent := make([]byte, fileSize)
bytesRead, err := file.Read(fileContent)
common.Check(err)
if int64(bytesRead) != fileSize {
common.RuntimeError(fmt.Sprintf("failed to read %d bytes from file %s",
fileSize, fileName))
}
// validate file content
asciiStlHeader := []byte{0x73, 0x6f, 0x6c, 0x69, 0x64}
if bytes.Equal(fileContent[0:5], asciiStlHeader) {
common.RuntimeError("ascii stl files are not supported: " + fileName)
}
if fileSize < headerSize+4 {
common.RuntimeError("invalid binary stl file: " + fileName)
}
buffer := bytes.NewBuffer(fileContent[headerSize:])
var trianglesCount int32
err = binary.Read(buffer, binary.LittleEndian, &trianglesCount)
common.Check(err)
if trianglesCount > maxTrianglesCount {
common.RuntimeError("triangles limit exceeded: " + fileName)
}
expectedSize := int64(headerSize + 4 + trianglesCount*facetSize)
if fileSize != expectedSize {
common.RuntimeError("invalid size of binary stl file: " + fileName)
}
// read mesh data
mesh := new(TriangleMesh)
mesh.normals = make([]Vector32, trianglesCount)
mesh.triangles = make([][3]int32, trianglesCount)
uniqueVertices := make(map[Vector32]int32)
for i := 0; i < int(trianglesCount); i++ {
binary.Read(buffer, binary.LittleEndian, &mesh.normals[i])
for k := 0; k < 3; k++ {
var v Vector32
binary.Read(buffer, binary.LittleEndian, &v)
vertexIndex, found := uniqueVertices[v]
if !found {
if len(mesh.vertices) > maxVerticesCount {
common.RuntimeError("vertices limit exceeded: " + fileName)
}
vertexIndex = int32(len(mesh.vertices))
uniqueVertices[v] = vertexIndex
mesh.vertices = append(mesh.vertices, v)
}
mesh.triangles[i][k] = vertexIndex
}
var attribsCount uint16
binary.Read(buffer, binary.LittleEndian, &attribsCount)
}
return mesh
}