pbrt/src/shapes/mesh.rs
2026-01-22 14:18:57 +00:00

526 lines
16 KiB
Rust

// use crate::Arena;
use crate::utils::sampling::PiecewiseConstant2D;
use anyhow::{Context, Result as AnyResult, bail};
use ply_rs::parser::Parser;
use ply_rs::ply::{DefaultElement, Property};
use shared::core::geometry::{Normal3f, Point2f, Point3f, Vector3f, VectorLike};
use shared::utils::mesh::{DeviceBilinearPatchMesh, DeviceTriangleMesh};
use shared::utils::{Ptr, Transform};
use std::fs::File;
use std::ops::Deref;
use std::path::Path;
/// Intermediate mesh from PLY
#[derive(Debug, Clone, Default)]
pub struct TriQuadMesh {
pub p: Vec<Point3f>,
pub n: Vec<Normal3f>,
pub uv: Vec<Point2f>,
pub face_indices: Vec<i32>,
pub tri_indices: Vec<i32>,
pub quad_indices: Vec<i32>,
}
#[derive(Debug)]
struct TriangleMeshStorage {
pub p: Vec<Point3f>,
pub n: Vec<Normal3f>,
pub s: Vec<Vector3f>,
pub uv: Vec<Point2f>,
pub vertex_indices: Vec<i32>,
pub face_indices: Vec<i32>,
}
#[derive(Debug)]
struct BilinearMeshStorage {
pub vertex_indices: Vec<i32>,
pub p: Vec<Point3f>,
pub n: Vec<Normal3f>,
pub uv: Vec<Point2f>,
pub image_distribution: Option<PiecewiseConstant2D>,
}
#[derive(Debug)]
pub struct TriangleMesh {
pub storage: Box<TriangleMeshStorage>,
pub device: DeviceTriangleMesh,
}
#[derive(Debug)]
pub struct BilinearPatchMesh {
pub storage: Box<BilinearMeshStorage>,
pub device: DeviceBilinearPatchMesh,
}
impl Deref for TriangleMesh {
type Target = DeviceTriangleMesh;
#[inline]
fn deref(&self) -> &Self::Target {
&self.device
}
}
impl Deref for BilinearPatchMesh {
type Target = DeviceBilinearPatchMesh;
#[inline]
fn deref(&self) -> &Self::Target {
&self.device
}
}
impl TriangleMesh {
pub fn new(
render_from_object: &Transform,
reverse_orientation: bool,
vertex_indices: Vec<i32>,
mut p: Vec<Point3f>,
mut n: Vec<Normal3f>,
mut s: Vec<Vector3f>,
uv: Vec<Point2f>,
face_indices: Vec<i32>,
) -> Self {
let n_triangles = vertex_indices.len() / 3;
let n_vertices = p.len();
// Transform positions to render space
for pt in p.iter_mut() {
*pt = render_from_object.apply_to_point(*pt);
}
// Transform and optionally flip normals
if !n.is_empty() {
assert_eq!(n_vertices, n.len(), "Normal count mismatch");
for nn in n.iter_mut() {
*nn = render_from_object.apply_to_normal(*nn);
if reverse_orientation {
*nn = -*nn;
}
}
}
// Transform tangents
if !s.is_empty() {
assert_eq!(n_vertices, s.len(), "Tangent count mismatch");
for ss in s.iter_mut() {
*ss = render_from_object.apply_to_vector(*ss);
}
}
// Validate UVs
if !uv.is_empty() {
assert_eq!(n_vertices, uv.len(), "UV count mismatch");
}
// Validate face indices
if !face_indices.is_empty() {
assert_eq!(n_triangles, face_indices.len(), "Face index count mismatch");
}
let transform_swaps_handedness = render_from_object.swaps_handedness();
let storage = Box::new(TriangleMeshStorage {
vertex_indices,
p,
n,
s,
uv,
face_indices,
});
// Build device struct with pointers into storage
let device = DeviceTriangleMesh {
n_triangles: n_triangles as u32,
n_vertices: n_vertices as u32,
vertex_indices: storage.vertex_indices.as_ptr().into(),
p: storage.p.as_ptr().into(),
n: if storage.n.is_empty() {
Ptr::null()
} else {
storage.n.as_ptr().into()
},
s: if storage.s.is_empty() {
Ptr::null()
} else {
storage.s.as_ptr().into()
},
uv: if storage.uv.is_empty() {
Ptr::null()
} else {
storage.uv.as_ptr().into()
},
face_indices: if storage.face_indices.is_empty() {
Ptr::null()
} else {
storage.face_indices.as_ptr().into()
},
reverse_orientation,
transform_swaps_handedness,
};
Self { storage, device }
}
pub fn positions(&self) -> &[Point3f] {
&self.storage.p
}
pub fn indices(&self) -> &[i32] {
&self.storage.vertex_indices
}
pub fn normals(&self) -> &[Normal3f] {
&self.storage.n
}
pub fn uvs(&self) -> &[Point2f] {
&self.storage.uv
}
}
impl BilinearPatchMesh {
pub fn new(
render_from_object: &Transform,
reverse_orientation: bool,
vertex_indices: Vec<ui2>,
mut p: Vec<Point3f>,
mut n: Vec<Normal3f>,
uv: Vec<Point2f>,
image_distribution: Option<PiecewiseConstant2D>,
) -> Self {
let n_patches = vertex_indices.len() / 4;
let n_vertices = p.len();
for pt in p.iter_mut() {
*pt = render_from_object.apply_to_point(*pt);
}
if !n.is_empty() {
assert_eq!(n_vertices, n.len(), "Normal count mismatch");
for nn in n.iter_mut() {
*nn = render_from_object.apply_to_normal(*nn);
if reverse_orientation {
*nn = -*nn;
}
}
}
if !uv.is_empty() {
assert_eq!(n_vertices, uv.len(), "UV count mismatch");
}
let transform_swaps_handedness = render_from_object.swaps_handedness();
let storage = Box::new(BilinearMeshStorage {
vertex_indices,
p,
n,
uv,
image_distribution,
});
let device = DeviceBilinearPatchMesh {
n_patches: n_patches as u32,
n_vertices: n_vertices as u32,
vertex_indices: storage.vertex_indices.as_ptr().into(),
p: storage.p.as_ptr().into(),
n: if storage.n.is_empty() {
Ptr::null()
} else {
storage.n.as_ptr().into()
},
uv: if storage.uv.is_empty() {
Ptr::null()
} else {
storage.uv.as_ptr().into()
},
reverse_orientation,
transform_swaps_handedness,
image_distribution: storage
.image_distribution
.as_ref()
.map(|d| Ptr::from(&d.device))
.unwrap_or(Ptr::null()),
};
Self { storage, device }
}
}
// ============================================================================
// PLY Helper Functions
// ============================================================================
fn get_float(elem: &DefaultElement, key: &str) -> AnyResult<f32> {
match elem.get(key) {
Some(Property::Float(v)) => Ok(*v),
Some(Property::Double(v)) => Ok(*v as f32),
Some(_) => bail!("Property {} is not a float", key),
None => bail!("Property {} not found", key),
}
}
fn get_int(elem: &DefaultElement, key: &str) -> AnyResult<i32> {
match elem.get(key) {
Some(Property::Int(v)) => Ok(*v),
Some(Property::UInt(v)) => Ok(*v as i32),
Some(Property::Short(v)) => Ok(*v as i32),
Some(Property::UShort(v)) => Ok(*v as i32),
Some(Property::Char(v)) => Ok(*v as i32),
Some(Property::UChar(v)) => Ok(*v as i32),
_ => bail!("Property {} not found or not integer", key),
}
}
fn get_float_any(elem: &DefaultElement, keys: &[&str]) -> Option<f32> {
for k in keys {
if let Ok(val) = get_float(elem, k) {
return Some(val);
}
}
None
}
fn get_list_uint(elem: &DefaultElement, key: &str) -> AnyResult<Vec<u32>> {
match elem.get(key) {
Some(Property::ListInt(vec)) => Ok(vec.iter().map(|&x| x as u32).collect()),
Some(Property::ListUInt(vec)) => Ok(vec.clone()),
Some(Property::ListUChar(vec)) => Ok(vec.iter().map(|&x| x as u32).collect()),
Some(Property::ListChar(vec)) => Ok(vec.iter().map(|&x| x as u32).collect()),
_ => bail!("Property {} is not a list", key),
}
}
// ============================================================================
// TriQuadMesh Implementation
// ============================================================================
impl TriQuadMesh {
pub fn read_ply<P: AsRef<Path>>(filename: P) -> AnyResult<Self> {
let path = filename.as_ref();
let filename_display = path.display().to_string();
let mut f = File::open(path)
.with_context(|| format!("Couldn't open PLY file \"{}\"", filename_display))?;
let p = Parser::<DefaultElement>::new();
let ply = p
.read_ply(&mut f)
.with_context(|| format!("Unable to read/parse PLY file \"{}\"", filename_display))?;
let mut mesh = TriQuadMesh::default();
// Parse vertices
if let Some(vertices) = ply.payload.get("vertex") {
if vertices.is_empty() {
bail!("{}: PLY file has no vertices", filename_display);
}
let first = &vertices[0];
let has_uv = (first.contains_key("u") && first.contains_key("v"))
|| (first.contains_key("s") && first.contains_key("t"))
|| (first.contains_key("texture_u") && first.contains_key("texture_v"))
|| (first.contains_key("texture_s") && first.contains_key("texture_t"));
let has_normal =
first.contains_key("nx") && first.contains_key("ny") && first.contains_key("nz");
mesh.p.reserve(vertices.len());
if has_normal {
mesh.n.reserve(vertices.len());
}
if has_uv {
mesh.uv.reserve(vertices.len());
}
for v_elem in vertices {
let x = get_float(v_elem, "x")?;
let y = get_float(v_elem, "y")?;
let z = get_float(v_elem, "z")?;
mesh.p.push(Point3f::new(x, y, z));
if has_normal {
let nx = get_float(v_elem, "nx").unwrap_or(0.0);
let ny = get_float(v_elem, "ny").unwrap_or(0.0);
let nz = get_float(v_elem, "nz").unwrap_or(0.0);
mesh.n.push(Normal3f::new(nx, ny, nz));
}
if has_uv {
let u =
get_float_any(v_elem, &["u", "s", "texture_u", "texture_s"]).unwrap_or(0.0);
let v =
get_float_any(v_elem, &["v", "t", "texture_v", "texture_t"]).unwrap_or(0.0);
mesh.uv.push(Point2f::new(u, v));
}
}
} else {
bail!("{}: PLY file has no vertex elements", filename_display);
}
// Parse faces
if let Some(faces) = ply.payload.get("face") {
mesh.tri_indices.reserve(faces.len() * 3);
mesh.quad_indices.reserve(faces.len() * 4);
for f_elem in faces {
if let Ok(fi) = get_int(f_elem, "face_indices") {
mesh.face_indices.push(fi);
}
if let Ok(indices) = get_list_uint(f_elem, "vertex_indices") {
match indices.len() {
3 => mesh.tri_indices.extend(indices.iter().map(|&i| i as i32)),
4 => mesh.quad_indices.extend(indices.iter().map(|&i| i as i32)),
n => {
log::warn!(
"{}: Skipping face with {} vertices (only 3 or 4 supported)",
filename_display,
n
);
}
}
} else {
bail!("{}: vertex_indices not found in face", filename_display);
}
}
} else {
bail!("{}: PLY file has no face elements", filename_display);
}
// Validate indices
let vertex_count = mesh.p.len() as i32;
for &idx in &mesh.tri_indices {
if idx >= vertex_count {
bail!(
"{}: Vertex index {} out of bounds [0..{})",
filename_display,
idx,
vertex_count
);
}
}
for &idx in &mesh.quad_indices {
if idx >= vertex_count {
bail!(
"{}: Vertex index {} out of bounds [0..{})",
filename_display,
idx,
vertex_count
);
}
}
Ok(mesh)
}
pub fn convert_to_only_triangles(&mut self) {
if self.quad_indices.is_empty() {
return;
}
// Each quad becomes 2 triangles
self.tri_indices.reserve(self.quad_indices.len() / 4 * 6);
for quad in self.quad_indices.chunks_exact(4) {
let (v0, v1, v2, v3) = (quad[0], quad[1], quad[2], quad[3]);
// Triangle 1: v0, v1, v2
self.tri_indices.push(v0);
self.tri_indices.push(v1);
self.tri_indices.push(v2);
// Triangle 2: v0, v2, v3
self.tri_indices.push(v0);
self.tri_indices.push(v2);
self.tri_indices.push(v3);
}
self.quad_indices.clear();
}
pub fn compute_normals(&mut self) {
// Initialize normals to zero
self.n = vec![Normal3f::new(0.0, 0.0, 0.0); self.p.len()];
// Accumulate face normals for triangles
for tri in self.tri_indices.chunks_exact(3) {
let (i0, i1, i2) = (tri[0] as usize, tri[1] as usize, tri[2] as usize);
let p0 = self.p[i0];
let p1 = self.p[i1];
let p2 = self.p[i2];
let v10 = p1 - p0;
let v20 = p2 - p0;
let face_normal = v10.cross(v20);
// Accumulate (will normalize later)
self.n[i0] = self.n[i0] + Normal3f::from(face_normal);
self.n[i1] = self.n[i1] + Normal3f::from(face_normal);
self.n[i2] = self.n[i2] + Normal3f::from(face_normal);
}
// Accumulate face normals for quads
for quad in self.quad_indices.chunks_exact(4) {
let indices: Vec<usize> = quad.iter().map(|&i| i as usize).collect();
let p0 = self.p[indices[0]];
let p1 = self.p[indices[1]];
let p2 = self.p[indices[2]];
let v10 = p1 - p0;
let v20 = p2 - p0;
let face_normal = v10.cross(v20);
for &idx in &indices {
self.n[idx] = self.n[idx] + Normal3f::from(face_normal);
}
}
// Normalize all normals
for normal in &mut self.n {
let len_sq = normal.norm_squared();
if len_sq > 0.0 {
*normal = *normal / len_sq.sqrt();
}
}
}
/// Convert to a TriangleMesh, consuming self
pub fn into_triangle_mesh(
mut self,
render_from_object: &Transform,
reverse_orientation: bool,
) -> TriangleMesh {
self.convert_to_only_triangles();
if self.n.is_empty() {
self.compute_normals();
}
TriangleMesh::new(
render_from_object,
reverse_orientation,
self.tri_indices,
self.p,
self.n,
Vec::new(), // s (tangents)
self.uv,
self.face_indices,
)
}
}
// ============================================================================
// Convenience: Create from PLY directly
// ============================================================================
impl TriangleMesh {
pub fn from_ply<P: AsRef<Path>>(
filename: P,
render_from_object: &Transform,
reverse_orientation: bool,
) -> AnyResult<Self> {
let mesh = TriQuadMesh::read_ply(filename)?;
Ok(mesh.into_triangle_mesh(render_from_object, reverse_orientation))
}
}