Read surface mesh from PLY file (#31)

data/.gitattributes

@@ -1,2 +1,3 @@
 *.vtk filter=lfs diff=lfs merge=lfs -text
 *.xyz filter=lfs diff=lfs merge=lfs -text
+*.ply filter=lfs diff=lfs merge=lfs -text

data/cube.ply

@@ -0,0 +1,51 @@
+ply
+format ascii 1.0
+comment Created by Blender 2.82 (sub 7) - www.blender.org, source file: ''
+element vertex 24
+property float x
+property float y
+property float z
+property float nx
+property float ny
+property float nz
+property float s
+property float t
+element face 12
+property list uchar uint vertex_indices
+end_header
+-1.000000 1.000000 1.000000 0.000000 0.000000 1.000000 0.875000 0.500000
+1.000000 -1.000000 1.000000 0.000000 0.000000 1.000000 0.625000 0.750000
+1.000000 1.000000 1.000000 0.000000 0.000000 1.000000 0.625000 0.500000
+1.000000 -1.000000 1.000000 0.000000 -1.000000 0.000000 0.625000 0.750000
+-1.000000 -1.000000 -1.000000 0.000000 -1.000000 0.000000 0.375000 1.000000
+1.000000 -1.000000 -1.000000 0.000000 -1.000000 0.000000 0.375000 0.750000
+-1.000000 -1.000000 1.000000 -1.000000 0.000000 0.000000 0.625000 0.000000
+-1.000000 1.000000 -1.000000 -1.000000 0.000000 0.000000 0.375000 0.250000
+-1.000000 -1.000000 -1.000000 -1.000000 0.000000 0.000000 0.375000 0.000000
+1.000000 1.000000 -1.000000 0.000000 0.000000 -1.000000 0.375000 0.500000
+-1.000000 -1.000000 -1.000000 0.000000 0.000000 -1.000000 0.125000 0.750000
+-1.000000 1.000000 -1.000000 0.000000 0.000000 -1.000000 0.125000 0.500000
+1.000000 1.000000 1.000000 1.000000 0.000000 -0.000000 0.625000 0.500000
+1.000000 -1.000000 -1.000000 1.000000 0.000000 -0.000000 0.375000 0.750000
+1.000000 1.000000 -1.000000 1.000000 0.000000 -0.000000 0.375000 0.500000
+-1.000000 1.000000 1.000000 0.000000 1.000000 -0.000000 0.625000 0.250000
+1.000000 1.000000 -1.000000 0.000000 1.000000 -0.000000 0.375000 0.500000
+-1.000000 1.000000 -1.000000 0.000000 1.000000 -0.000000 0.375000 0.250000
+-1.000000 -1.000000 1.000000 0.000000 -0.000000 1.000000 0.875000 0.750000
+-1.000000 -1.000000 1.000000 0.000000 -1.000000 0.000000 0.625000 1.000000
+-1.000000 1.000000 1.000000 -1.000000 0.000000 0.000000 0.625000 0.250000
+1.000000 -1.000000 -1.000000 0.000000 0.000000 -1.000000 0.375000 0.750000
+1.000000 -1.000000 1.000000 1.000000 0.000000 0.000000 0.625000 0.750000
+1.000000 1.000000 1.000000 0.000000 1.000000 -0.000000 0.625000 0.500000
+3 0 1 2
+3 3 4 5
+3 6 7 8
+3 9 10 11
+3 12 13 14
+3 15 16 17
+3 0 18 1
+3 3 19 4
+3 6 20 7
+3 9 21 10
+3 12 22 13
+3 15 23 16

splashsurf/src/io.rs

@@ -143,6 +143,7 @@ pub fn read_surface_mesh<R: Real, P: AsRef<Path>>(
 
  match extension.to_lowercase().as_str() {
  "vtk" => vtk_format::surface_mesh_from_vtk(&input_file)?,
+ "ply" => ply_format::surface_mesh_from_ply(&input_file)?,
  _ => {
  return Err(anyhow!(
  "Unsupported file format extension \"{}\" for reading surface meshes",

splashsurf/src/io/ply_format.rs

@@ -4,6 +4,10 @@ use anyhow::{anyhow, Context};
 use ply_rs as ply;
 use ply_rs::ply::Property;
 
+use splashsurf_lib::mesh::AttributeData;
+use splashsurf_lib::mesh::MeshAttribute;
+use splashsurf_lib::mesh::MeshWithData;
+use splashsurf_lib::mesh::TriMesh3d;
 use splashsurf_lib::nalgebra::Vector3;
 use splashsurf_lib::Real;
 
@@ -49,3 +53,139 @@ pub fn particles_from_ply<R: Real, P: AsRef<Path>>(
 
  Ok(particles)
 }
+
+/// Tries to read a surface mesh from the VTK file at the given path
+pub fn surface_mesh_from_ply<R: Real, P: AsRef<Path>>(
+ ply_file: P,
+) -> Result<MeshWithData<R, TriMesh3d<R>>, anyhow::Error> {
+ let mut ply_file = std::fs::File::open(ply_file).unwrap();
+ let parser = ply::parser::Parser::<ply::ply::DefaultElement>::new();
+
+ let ply = parser
+ .read_ply(&mut ply_file)
+ .context("Failed to read PLY file")?;
+ let vertices_normals = ply
+ .payload
+ .get("vertex")
+ .ok_or(anyhow!("PLY file is missing a 'vertex' element"))?;
+
+ let vertices_normals: Vec<(Vector3<_>, Vector3<_>)> = vertices_normals
+ .into_iter()
+ .map(|e| {
+ let vertex = (
+ e.get("x").unwrap(),
+ e.get("y").unwrap(),
+ e.get("z").unwrap(),
+ e.get("nx").unwrap(),
+ e.get("ny").unwrap(),
+ e.get("nz").unwrap(),
+ );
+
+ let v = match vertex {
+ (
+ Property::Float(x),
+ Property::Float(y),
+ Property::Float(z),
+ Property::Float(nx),
+ Property::Float(ny),
+ Property::Float(nz),
+ ) => (
+ Vector3::new(
+ R::from_f32(*x).unwrap(),
+ R::from_f32(*y).unwrap(),
+ R::from_f32(*z).unwrap(),
+ ),
+ Vector3::new(
+ R::from_f32(*nx).unwrap(),
+ R::from_f32(*ny).unwrap(),
+ R::from_f32(*nz).unwrap(),
+ ),
+ ),
+ _ => {
+ return Err(anyhow!(
+ "Vertex properties have wrong PLY data type (expected float)"
+ ))
+ }
+ };
+
+ Ok(v)
+ })
+ .map(|vn| vn.unwrap())
+ .collect();
+
+ let vertices: Vec<Vector3<_>> = vertices_normals.iter().map(|vn| vn.0.clone()).collect();
+ let normals: Vec<Vector3<_>> = vertices_normals.iter().map(|vn| vn.1.clone()).collect();
+
+ let faces = ply
+ .payload
+ .get("face")
+ .ok_or(anyhow!("PLY file is missing a 'face' element"))?;
+
+ let triangles = faces
+ .into_iter()
+ .map(|e| {
+ // This is as per what blender creates for a
+ let indices = e.get("vertex_indices");
+ if let Some(indices) = indices {
+ if let Property::ListUInt(indices) = indices {
+ if indices.len() == 3 {
+ return Ok([
+ indices[0] as usize,
+ indices[1] as usize,
+ indices[2] as usize,
+ ]);
+ } else {
+ return Err(anyhow!(
+ "Invalid number of vertex indices per cell: {}",
+ indices.len()
+ ));
+ }
+ } else {
+ return Err(anyhow!(
+ "Index properties have wrong PLY data type (expected uint)"
+ ));
+ }
+ } else {
+ return Err(anyhow!(
+ "Vertex properties have wrong PLY data type (expected uint)"
+ ));
+ }
+ })
+ .map(|e| e.unwrap())
+ .collect();
+
+ let normals = MeshAttribute::new("normals", AttributeData::Vector3Real(normals));
+ Ok(MeshWithData::new(TriMesh3d {
+ vertices,
+ triangles,
+ })
+ .with_point_data(normals))
+}
+
+#[cfg(test)]
+pub mod test {
+ use super::*;
+
+ #[test]
+ fn test_convert_cube() -> Result<(), anyhow::Error> {
+ let input_file = Path::new("../data/cube.ply");
+
+ let mesh: MeshWithData<f32, _> = surface_mesh_from_ply(input_file).with_context(|| {
+ format!(
+ "Failed to load surface mesh from file \"{}\"",
+ input_file.display()
+ )
+ })?;
+
+ assert_eq!(mesh.mesh.vertices.len(), 24);
+ assert_eq!(mesh.mesh.triangles.len(), 12);
+ let normals = mesh.point_attributes.iter().find(|a| a.name == "normals");
+ if let Some(MeshAttribute { data, .. }) = normals {
+ if let AttributeData::Vector3Real(normals) = data {
+ assert_eq!(normals.len(), 24)
+ }
+ }
+
+ Ok(())
+ }
+}