tolelom
a9f5b11f69
- Mini JSON parser (no external deps) for glTF support - GLB binary format: header, JSON chunk, BIN chunk - Embedded base64 buffer URI support - Accessor/BufferView extraction (position, normal, uv, tangent, indices) - PBR material extraction (baseColor, metallic, roughness) - Auto compute_tangents when not provided Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
581 lines
22 KiB
Rust
581 lines
22 KiB
Rust
use crate::json_parser::{self, JsonValue};
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use crate::vertex::MeshVertex;
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use crate::obj::compute_tangents;
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pub struct GltfData {
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pub meshes: Vec<GltfMesh>,
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}
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pub struct GltfMesh {
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pub vertices: Vec<MeshVertex>,
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pub indices: Vec<u32>,
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pub name: Option<String>,
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pub material: Option<GltfMaterial>,
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}
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pub struct GltfMaterial {
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pub base_color: [f32; 4],
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pub metallic: f32,
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pub roughness: f32,
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}
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const GLB_MAGIC: u32 = 0x46546C67;
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const GLB_VERSION: u32 = 2;
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const CHUNK_JSON: u32 = 0x4E4F534A;
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const CHUNK_BIN: u32 = 0x004E4942;
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pub fn parse_gltf(data: &[u8]) -> Result<GltfData, String> {
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if data.len() < 4 {
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return Err("Data too short".into());
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}
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// Detect format: GLB (binary) or JSON
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let magic = u32::from_le_bytes([data[0], data[1], data[2], data[3]]);
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if magic == GLB_MAGIC {
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parse_glb(data)
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} else if data[0] == b'{' {
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parse_gltf_json(data)
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} else {
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Err("Unknown glTF format: not GLB or JSON".into())
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}
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}
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fn parse_glb(data: &[u8]) -> Result<GltfData, String> {
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if data.len() < 12 {
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return Err("GLB header too short".into());
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}
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let version = u32::from_le_bytes([data[4], data[5], data[6], data[7]]);
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if version != GLB_VERSION {
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return Err(format!("Unsupported GLB version: {} (expected 2)", version));
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}
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let _total_len = u32::from_le_bytes([data[8], data[9], data[10], data[11]]) as usize;
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// Parse chunks
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let mut pos = 12;
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let mut json_str = String::new();
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let mut bin_data: Vec<u8> = Vec::new();
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while pos + 8 <= data.len() {
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let chunk_len = u32::from_le_bytes([data[pos], data[pos+1], data[pos+2], data[pos+3]]) as usize;
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let chunk_type = u32::from_le_bytes([data[pos+4], data[pos+5], data[pos+6], data[pos+7]]);
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pos += 8;
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if pos + chunk_len > data.len() {
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return Err("Chunk extends past data".into());
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}
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match chunk_type {
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CHUNK_JSON => {
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json_str = std::str::from_utf8(&data[pos..pos + chunk_len])
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.map_err(|_| "Invalid UTF-8 in JSON chunk".to_string())?
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.to_string();
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}
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CHUNK_BIN => {
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bin_data = data[pos..pos + chunk_len].to_vec();
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}
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_ => {} // skip unknown chunks
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}
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pos += chunk_len;
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// Chunks are 4-byte aligned
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pos = (pos + 3) & !3;
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}
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if json_str.is_empty() {
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return Err("No JSON chunk found in GLB".into());
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}
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let json = json_parser::parse_json(&json_str)?;
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let buffers = vec![bin_data]; // GLB has one implicit binary buffer
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extract_meshes(&json, &buffers)
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}
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fn parse_gltf_json(data: &[u8]) -> Result<GltfData, String> {
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let json_str = std::str::from_utf8(data).map_err(|_| "Invalid UTF-8".to_string())?;
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let json = json_parser::parse_json(json_str)?;
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// Resolve buffers (embedded base64 URIs)
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let mut buffers = Vec::new();
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if let Some(bufs) = json.get("buffers").and_then(|v| v.as_array()) {
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for buf in bufs {
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if let Some(uri) = buf.get("uri").and_then(|v| v.as_str()) {
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if let Some(b64) = uri.strip_prefix("data:application/octet-stream;base64,") {
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buffers.push(decode_base64(b64)?);
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} else if let Some(b64) = uri.strip_prefix("data:application/gltf-buffer;base64,") {
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buffers.push(decode_base64(b64)?);
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} else {
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return Err(format!("External buffer URIs not supported: {}", uri));
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}
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} else {
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buffers.push(Vec::new());
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}
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}
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}
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extract_meshes(&json, &buffers)
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}
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fn decode_base64(input: &str) -> Result<Vec<u8>, String> {
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let table = |c: u8| -> Result<u8, String> {
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match c {
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b'A'..=b'Z' => Ok(c - b'A'),
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b'a'..=b'z' => Ok(c - b'a' + 26),
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b'0'..=b'9' => Ok(c - b'0' + 52),
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b'+' => Ok(62),
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b'/' => Ok(63),
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b'=' => Ok(0), // padding
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_ => Err(format!("Invalid base64 character: {}", c as char)),
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}
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};
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let bytes: Vec<u8> = input.bytes().filter(|&b| b != b'\n' && b != b'\r' && b != b' ').collect();
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let mut out = Vec::with_capacity(bytes.len() * 3 / 4);
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for chunk in bytes.chunks(4) {
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let b0 = table(chunk[0])?;
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let b1 = if chunk.len() > 1 { table(chunk[1])? } else { 0 };
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let b2 = if chunk.len() > 2 { table(chunk[2])? } else { 0 };
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let b3 = if chunk.len() > 3 { table(chunk[3])? } else { 0 };
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out.push((b0 << 2) | (b1 >> 4));
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if chunk.len() > 2 && chunk[2] != b'=' {
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out.push((b1 << 4) | (b2 >> 2));
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}
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if chunk.len() > 3 && chunk[3] != b'=' {
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out.push((b2 << 6) | b3);
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}
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}
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Ok(out)
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}
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fn extract_meshes(json: &JsonValue, buffers: &[Vec<u8>]) -> Result<GltfData, String> {
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let empty_arr: Vec<JsonValue> = Vec::new();
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let accessors = json.get("accessors").and_then(|v| v.as_array()).unwrap_or(&empty_arr);
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let buffer_views = json.get("bufferViews").and_then(|v| v.as_array()).unwrap_or(&empty_arr);
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let materials_json = json.get("materials").and_then(|v| v.as_array());
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let mut meshes = Vec::new();
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let mesh_list = json.get("meshes").and_then(|v| v.as_array())
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.ok_or("No meshes in glTF")?;
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for mesh_val in mesh_list {
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let name = mesh_val.get("name").and_then(|v| v.as_str()).map(|s| s.to_string());
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let primitives = mesh_val.get("primitives").and_then(|v| v.as_array())
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.ok_or("Mesh has no primitives")?;
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for prim in primitives {
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let attrs = prim.get("attributes").and_then(|v| v.as_object())
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.ok_or("Primitive has no attributes")?;
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// Read position data (required)
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let pos_idx = attrs.iter().find(|(k, _)| k == "POSITION")
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.and_then(|(_, v)| v.as_u32())
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.ok_or("Missing POSITION attribute")? as usize;
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let positions = read_accessor_vec3(accessors, buffer_views, buffers, pos_idx)?;
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// Read normals (optional)
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let normals = if let Some(idx) = attrs.iter().find(|(k, _)| k == "NORMAL").and_then(|(_, v)| v.as_u32()) {
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read_accessor_vec3(accessors, buffer_views, buffers, idx as usize)?
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} else {
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vec![[0.0, 1.0, 0.0]; positions.len()]
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};
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// Read UVs (optional)
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let uvs = if let Some(idx) = attrs.iter().find(|(k, _)| k == "TEXCOORD_0").and_then(|(_, v)| v.as_u32()) {
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read_accessor_vec2(accessors, buffer_views, buffers, idx as usize)?
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} else {
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vec![[0.0, 0.0]; positions.len()]
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};
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// Read tangents (optional)
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let tangents = if let Some(idx) = attrs.iter().find(|(k, _)| k == "TANGENT").and_then(|(_, v)| v.as_u32()) {
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Some(read_accessor_vec4(accessors, buffer_views, buffers, idx as usize)?)
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} else {
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None
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};
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// Read indices
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let indices = if let Some(idx) = prim.get("indices").and_then(|v| v.as_u32()) {
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read_accessor_indices(accessors, buffer_views, buffers, idx as usize)?
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} else {
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// No indices — generate sequential
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(0..positions.len() as u32).collect()
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};
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// Assemble vertices
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let mut vertices: Vec<MeshVertex> = Vec::with_capacity(positions.len());
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for i in 0..positions.len() {
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vertices.push(MeshVertex {
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position: positions[i],
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normal: normals[i],
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uv: uvs[i],
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tangent: tangents.as_ref().map_or([0.0; 4], |t| t[i]),
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});
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}
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// Compute tangents if not provided
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if tangents.is_none() {
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compute_tangents(&mut vertices, &indices);
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}
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// Read material
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let material = prim.get("material")
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.and_then(|v| v.as_u32())
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.and_then(|idx| materials_json?.get(idx as usize))
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.and_then(|mat| extract_material(mat));
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meshes.push(GltfMesh { vertices, indices, name: name.clone(), material });
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}
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}
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Ok(GltfData { meshes })
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}
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fn get_buffer_data<'a>(
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accessor: &JsonValue,
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buffer_views: &[JsonValue],
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buffers: &'a [Vec<u8>],
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) -> Result<(&'a [u8], usize), String> {
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let bv_idx = accessor.get("bufferView").and_then(|v| v.as_u32())
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.ok_or("Accessor missing bufferView")? as usize;
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let bv = buffer_views.get(bv_idx).ok_or("BufferView index out of range")?;
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let buf_idx = bv.get("buffer").and_then(|v| v.as_u32()).unwrap_or(0) as usize;
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let bv_offset = bv.get("byteOffset").and_then(|v| v.as_u32()).unwrap_or(0) as usize;
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let acc_offset = accessor.get("byteOffset").and_then(|v| v.as_u32()).unwrap_or(0) as usize;
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let buffer = buffers.get(buf_idx).ok_or("Buffer index out of range")?;
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let offset = bv_offset + acc_offset;
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Ok((buffer, offset))
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}
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fn read_accessor_vec3(
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accessors: &[JsonValue], buffer_views: &[JsonValue], buffers: &[Vec<u8>], idx: usize,
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) -> Result<Vec<[f32; 3]>, String> {
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let acc = accessors.get(idx).ok_or("Accessor index out of range")?;
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let count = acc.get("count").and_then(|v| v.as_u32()).ok_or("Missing count")? as usize;
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let (buffer, offset) = get_buffer_data(acc, buffer_views, buffers)?;
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let mut result = Vec::with_capacity(count);
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for i in 0..count {
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let o = offset + i * 12;
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if o + 12 > buffer.len() { return Err("Buffer overflow reading vec3".into()); }
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let x = f32::from_le_bytes([buffer[o], buffer[o+1], buffer[o+2], buffer[o+3]]);
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let y = f32::from_le_bytes([buffer[o+4], buffer[o+5], buffer[o+6], buffer[o+7]]);
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let z = f32::from_le_bytes([buffer[o+8], buffer[o+9], buffer[o+10], buffer[o+11]]);
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result.push([x, y, z]);
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}
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Ok(result)
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}
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fn read_accessor_vec2(
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accessors: &[JsonValue], buffer_views: &[JsonValue], buffers: &[Vec<u8>], idx: usize,
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) -> Result<Vec<[f32; 2]>, String> {
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let acc = accessors.get(idx).ok_or("Accessor index out of range")?;
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let count = acc.get("count").and_then(|v| v.as_u32()).ok_or("Missing count")? as usize;
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let (buffer, offset) = get_buffer_data(acc, buffer_views, buffers)?;
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let mut result = Vec::with_capacity(count);
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for i in 0..count {
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let o = offset + i * 8;
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if o + 8 > buffer.len() { return Err("Buffer overflow reading vec2".into()); }
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let x = f32::from_le_bytes([buffer[o], buffer[o+1], buffer[o+2], buffer[o+3]]);
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let y = f32::from_le_bytes([buffer[o+4], buffer[o+5], buffer[o+6], buffer[o+7]]);
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result.push([x, y]);
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}
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Ok(result)
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}
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fn read_accessor_vec4(
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accessors: &[JsonValue], buffer_views: &[JsonValue], buffers: &[Vec<u8>], idx: usize,
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) -> Result<Vec<[f32; 4]>, String> {
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let acc = accessors.get(idx).ok_or("Accessor index out of range")?;
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let count = acc.get("count").and_then(|v| v.as_u32()).ok_or("Missing count")? as usize;
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let (buffer, offset) = get_buffer_data(acc, buffer_views, buffers)?;
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let mut result = Vec::with_capacity(count);
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for i in 0..count {
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let o = offset + i * 16;
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if o + 16 > buffer.len() { return Err("Buffer overflow reading vec4".into()); }
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let x = f32::from_le_bytes([buffer[o], buffer[o+1], buffer[o+2], buffer[o+3]]);
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let y = f32::from_le_bytes([buffer[o+4], buffer[o+5], buffer[o+6], buffer[o+7]]);
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let z = f32::from_le_bytes([buffer[o+8], buffer[o+9], buffer[o+10], buffer[o+11]]);
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let w = f32::from_le_bytes([buffer[o+12], buffer[o+13], buffer[o+14], buffer[o+15]]);
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result.push([x, y, z, w]);
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}
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Ok(result)
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}
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fn read_accessor_indices(
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accessors: &[JsonValue], buffer_views: &[JsonValue], buffers: &[Vec<u8>], idx: usize,
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) -> Result<Vec<u32>, String> {
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let acc = accessors.get(idx).ok_or("Accessor index out of range")?;
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let count = acc.get("count").and_then(|v| v.as_u32()).ok_or("Missing count")? as usize;
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let comp_type = acc.get("componentType").and_then(|v| v.as_u32()).ok_or("Missing componentType")?;
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let (buffer, offset) = get_buffer_data(acc, buffer_views, buffers)?;
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let mut result = Vec::with_capacity(count);
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match comp_type {
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5121 => { // UNSIGNED_BYTE
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for i in 0..count {
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if offset + i >= buffer.len() { return Err("Buffer overflow reading u8 indices".into()); }
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result.push(buffer[offset + i] as u32);
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}
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}
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5123 => { // UNSIGNED_SHORT
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for i in 0..count {
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let o = offset + i * 2;
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if o + 2 > buffer.len() { return Err("Buffer overflow reading u16 indices".into()); }
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result.push(u16::from_le_bytes([buffer[o], buffer[o+1]]) as u32);
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}
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}
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5125 => { // UNSIGNED_INT
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for i in 0..count {
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let o = offset + i * 4;
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if o + 4 > buffer.len() { return Err("Buffer overflow reading u32 indices".into()); }
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result.push(u32::from_le_bytes([buffer[o], buffer[o+1], buffer[o+2], buffer[o+3]]));
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}
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}
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_ => return Err(format!("Unsupported index component type: {}", comp_type)),
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}
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Ok(result)
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}
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fn extract_material(mat: &JsonValue) -> Option<GltfMaterial> {
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let pbr = mat.get("pbrMetallicRoughness")?;
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let base_color = if let Some(arr) = pbr.get("baseColorFactor").and_then(|v| v.as_array()) {
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[
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arr.get(0).and_then(|v| v.as_f64()).unwrap_or(1.0) as f32,
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arr.get(1).and_then(|v| v.as_f64()).unwrap_or(1.0) as f32,
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arr.get(2).and_then(|v| v.as_f64()).unwrap_or(1.0) as f32,
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arr.get(3).and_then(|v| v.as_f64()).unwrap_or(1.0) as f32,
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]
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} else {
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[1.0, 1.0, 1.0, 1.0]
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};
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let metallic = pbr.get("metallicFactor").and_then(|v| v.as_f64()).unwrap_or(1.0) as f32;
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let roughness = pbr.get("roughnessFactor").and_then(|v| v.as_f64()).unwrap_or(1.0) as f32;
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Some(GltfMaterial { base_color, metallic, roughness })
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}
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// Helper functions for tests
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#[allow(dead_code)]
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fn read_floats(buffer: &[u8], offset: usize, count: usize) -> Vec<f32> {
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(0..count).map(|i| {
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let o = offset + i * 4;
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f32::from_le_bytes([buffer[o], buffer[o+1], buffer[o+2], buffer[o+3]])
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}).collect()
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}
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#[allow(dead_code)]
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fn read_indices_u16(buffer: &[u8], offset: usize, count: usize) -> Vec<u32> {
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(0..count).map(|i| {
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let o = offset + i * 2;
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u16::from_le_bytes([buffer[o], buffer[o+1]]) as u32
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}).collect()
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}
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#[cfg(test)]
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mod tests {
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use super::*;
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#[test]
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fn test_glb_header_magic() {
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// Invalid magic
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let data = [0u8; 12];
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assert!(parse_gltf(&data).is_err());
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}
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#[test]
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fn test_glb_header_version() {
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// Valid magic but wrong version
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let mut data = Vec::new();
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data.extend_from_slice(&0x46546C67u32.to_le_bytes()); // magic "glTF"
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data.extend_from_slice(&1u32.to_le_bytes()); // version 1 (we need 2)
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data.extend_from_slice(&12u32.to_le_bytes()); // length
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assert!(parse_gltf(&data).is_err());
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}
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#[test]
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fn test_base64_decode() {
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let encoded = "SGVsbG8="; // "Hello"
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let decoded = decode_base64(encoded).unwrap();
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assert_eq!(decoded, b"Hello");
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}
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#[test]
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fn test_base64_decode_no_padding() {
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let encoded = "SGVsbG8"; // "Hello" without padding
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let decoded = decode_base64(encoded).unwrap();
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assert_eq!(decoded, b"Hello");
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}
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#[test]
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fn test_read_f32_accessor() {
|
|
// Simulate a buffer with 3 float32 values
|
|
let buffer: Vec<u8> = [1.0f32, 2.0, 3.0].iter()
|
|
.flat_map(|f| f.to_le_bytes())
|
|
.collect();
|
|
let data = read_floats(&buffer, 0, 3);
|
|
assert_eq!(data, vec![1.0, 2.0, 3.0]);
|
|
}
|
|
|
|
#[test]
|
|
fn test_read_u16_indices() {
|
|
let buffer: Vec<u8> = [0u16, 1, 2].iter()
|
|
.flat_map(|i| i.to_le_bytes())
|
|
.collect();
|
|
let indices = read_indices_u16(&buffer, 0, 3);
|
|
assert_eq!(indices, vec![0u32, 1, 2]);
|
|
}
|
|
|
|
#[test]
|
|
fn test_parse_minimal_glb() {
|
|
let glb = build_minimal_glb_triangle();
|
|
let data = parse_gltf(&glb).unwrap();
|
|
assert_eq!(data.meshes.len(), 1);
|
|
let mesh = &data.meshes[0];
|
|
assert_eq!(mesh.vertices.len(), 3);
|
|
assert_eq!(mesh.indices.len(), 3);
|
|
// Verify positions
|
|
assert_eq!(mesh.vertices[0].position, [0.0, 0.0, 0.0]);
|
|
assert_eq!(mesh.vertices[1].position, [1.0, 0.0, 0.0]);
|
|
assert_eq!(mesh.vertices[2].position, [0.0, 1.0, 0.0]);
|
|
}
|
|
|
|
#[test]
|
|
fn test_parse_glb_with_material() {
|
|
let glb = build_glb_with_material();
|
|
let data = parse_gltf(&glb).unwrap();
|
|
let mesh = &data.meshes[0];
|
|
let mat = mesh.material.as_ref().unwrap();
|
|
assert!((mat.base_color[0] - 1.0).abs() < 0.01);
|
|
assert!((mat.metallic - 0.5).abs() < 0.01);
|
|
assert!((mat.roughness - 0.8).abs() < 0.01);
|
|
}
|
|
|
|
/// Build a minimal GLB with one triangle.
|
|
fn build_minimal_glb_triangle() -> Vec<u8> {
|
|
// Binary buffer: 3 positions (vec3) + 3 indices (u16)
|
|
let mut bin = Vec::new();
|
|
// Positions: 3 * vec3 = 36 bytes
|
|
for &v in &[0.0f32, 0.0, 0.0, 1.0, 0.0, 0.0, 0.0, 1.0, 0.0] {
|
|
bin.extend_from_slice(&v.to_le_bytes());
|
|
}
|
|
// Indices: 3 * u16 = 6 bytes + 2 padding = 8 bytes
|
|
for &i in &[0u16, 1, 2] {
|
|
bin.extend_from_slice(&i.to_le_bytes());
|
|
}
|
|
bin.extend_from_slice(&[0, 0]); // padding to 4-byte alignment
|
|
|
|
let json_str = format!(r#"{{
|
|
"asset": {{"version": "2.0"}},
|
|
"buffers": [{{"byteLength": {}}}],
|
|
"bufferViews": [
|
|
{{"buffer": 0, "byteOffset": 0, "byteLength": 36}},
|
|
{{"buffer": 0, "byteOffset": 36, "byteLength": 6}}
|
|
],
|
|
"accessors": [
|
|
{{"bufferView": 0, "componentType": 5126, "count": 3, "type": "VEC3",
|
|
"max": [1.0, 1.0, 0.0], "min": [0.0, 0.0, 0.0]}},
|
|
{{"bufferView": 1, "componentType": 5123, "count": 3, "type": "SCALAR"}}
|
|
],
|
|
"meshes": [{{
|
|
"name": "Triangle",
|
|
"primitives": [{{
|
|
"attributes": {{"POSITION": 0}},
|
|
"indices": 1
|
|
}}]
|
|
}}]
|
|
}}"#, bin.len());
|
|
|
|
let json_bytes = json_str.as_bytes();
|
|
// Pad JSON to 4-byte alignment
|
|
let json_padded_len = (json_bytes.len() + 3) & !3;
|
|
let mut json_padded = json_bytes.to_vec();
|
|
while json_padded.len() < json_padded_len {
|
|
json_padded.push(b' ');
|
|
}
|
|
|
|
let total_len = 12 + 8 + json_padded.len() + 8 + bin.len();
|
|
let mut glb = Vec::with_capacity(total_len);
|
|
|
|
// Header
|
|
glb.extend_from_slice(&0x46546C67u32.to_le_bytes()); // magic
|
|
glb.extend_from_slice(&2u32.to_le_bytes()); // version
|
|
glb.extend_from_slice(&(total_len as u32).to_le_bytes());
|
|
|
|
// JSON chunk
|
|
glb.extend_from_slice(&(json_padded.len() as u32).to_le_bytes());
|
|
glb.extend_from_slice(&0x4E4F534Au32.to_le_bytes()); // "JSON"
|
|
glb.extend_from_slice(&json_padded);
|
|
|
|
// BIN chunk
|
|
glb.extend_from_slice(&(bin.len() as u32).to_le_bytes());
|
|
glb.extend_from_slice(&0x004E4942u32.to_le_bytes()); // "BIN\0"
|
|
glb.extend_from_slice(&bin);
|
|
|
|
glb
|
|
}
|
|
|
|
/// Build a GLB with one triangle and a material.
|
|
fn build_glb_with_material() -> Vec<u8> {
|
|
let mut bin = Vec::new();
|
|
for &v in &[0.0f32, 0.0, 0.0, 1.0, 0.0, 0.0, 0.0, 1.0, 0.0] {
|
|
bin.extend_from_slice(&v.to_le_bytes());
|
|
}
|
|
for &i in &[0u16, 1, 2] {
|
|
bin.extend_from_slice(&i.to_le_bytes());
|
|
}
|
|
bin.extend_from_slice(&[0, 0]); // padding
|
|
|
|
let json_str = format!(r#"{{
|
|
"asset": {{"version": "2.0"}},
|
|
"buffers": [{{"byteLength": {}}}],
|
|
"bufferViews": [
|
|
{{"buffer": 0, "byteOffset": 0, "byteLength": 36}},
|
|
{{"buffer": 0, "byteOffset": 36, "byteLength": 6}}
|
|
],
|
|
"accessors": [
|
|
{{"bufferView": 0, "componentType": 5126, "count": 3, "type": "VEC3",
|
|
"max": [1.0, 1.0, 0.0], "min": [0.0, 0.0, 0.0]}},
|
|
{{"bufferView": 1, "componentType": 5123, "count": 3, "type": "SCALAR"}}
|
|
],
|
|
"materials": [{{
|
|
"pbrMetallicRoughness": {{
|
|
"baseColorFactor": [1.0, 0.0, 0.0, 1.0],
|
|
"metallicFactor": 0.5,
|
|
"roughnessFactor": 0.8
|
|
}}
|
|
}}],
|
|
"meshes": [{{
|
|
"name": "Triangle",
|
|
"primitives": [{{
|
|
"attributes": {{"POSITION": 0}},
|
|
"indices": 1,
|
|
"material": 0
|
|
}}]
|
|
}}]
|
|
}}"#, bin.len());
|
|
|
|
let json_bytes = json_str.as_bytes();
|
|
let json_padded_len = (json_bytes.len() + 3) & !3;
|
|
let mut json_padded = json_bytes.to_vec();
|
|
while json_padded.len() < json_padded_len {
|
|
json_padded.push(b' ');
|
|
}
|
|
|
|
let total_len = 12 + 8 + json_padded.len() + 8 + bin.len();
|
|
let mut glb = Vec::with_capacity(total_len);
|
|
|
|
glb.extend_from_slice(&0x46546C67u32.to_le_bytes());
|
|
glb.extend_from_slice(&2u32.to_le_bytes());
|
|
glb.extend_from_slice(&(total_len as u32).to_le_bytes());
|
|
|
|
glb.extend_from_slice(&(json_padded.len() as u32).to_le_bytes());
|
|
glb.extend_from_slice(&0x4E4F534Au32.to_le_bytes());
|
|
glb.extend_from_slice(&json_padded);
|
|
|
|
glb.extend_from_slice(&(bin.len() as u32).to_le_bytes());
|
|
glb.extend_from_slice(&0x004E4942u32.to_le_bytes());
|
|
glb.extend_from_slice(&bin);
|
|
|
|
glb
|
|
}
|
|
}
|