importer/obj: basic material handling. dont panic when encountering v/vt components

src/importer/mod.rs

@@ -1,14 +1,81 @@
 mod obj;
 
-use std::path::PathBuf;
+use std::{path::PathBuf, collections::HashMap};
 
 use crate::{mesh::Vertex, aabb::AABB};
 
+#[derive(Debug, Clone)]
+pub enum TextureType {
+    Ambient,
+    Diffuse,
+    Specular,
+    SpecularHighlight,
+    Bump,
+    Displacement,
+    Decal,
+    Reflection,
+    Emissive
+}
+
+#[derive(Debug, Clone)]
+pub struct Material {
+    pub name: String,
+    pub ambient_color: glm::Vec3,
+    pub diffuse_color: glm::Vec3,
+    pub specular_color: glm::Vec3,
+    pub specular_exponent: f32,
+    pub opacity: f32,
+    pub textures: HashMap<String, TextureType>,
+}
+
+impl Material {
+    fn new(name: String, ambient: glm::Vec3, diffuse: glm::Vec3, specular: glm::Vec3, shininess: f32, opacity: f32, textures: HashMap<String, TextureType>) -> Self {
+        Self {
+            name,
+            ambient_color: ambient,
+            diffuse_color: diffuse,
+            specular_color: specular,
+            specular_exponent: shininess,
+            opacity,
+            textures
+        }
+    }
+}
+
+impl Default for Material {
+    fn default() -> Self {
+        Self {
+            name: "default_mat".to_string(),
+            ambient_color: glm::vec3(0.4, 0.4, 0.4),
+            diffuse_color: glm::vec3(0.7, 0.7, 0.7),
+            specular_color: glm::vec3(0.1, 0.1, 0.1),
+            specular_exponent: 32.0,
+            opacity: 1.0,
+            textures: HashMap::new()
+        }
+    }
+}
+
+impl std::fmt::Display for Material {
+    fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
+        write!(
+            f,
+            "Ambient: {:?}\nDiffuse: {:?}\nSpecular: {:?}\nShininess: {}\nOpacity: {}",
+            self.ambient_color,
+            self.diffuse_color,
+            self.specular_color,
+            self.specular_exponent,
+            self.opacity
+            )
+    }
+}
+
 #[derive(Debug)]
 pub struct ObjMesh {
     pub name: String,
     pub vertices: Vec<Vertex>,
     pub indices: Vec<u32>,
+    pub material: Option<Material>,
 }
 
 #[derive(Debug)]
@@ -26,6 +93,6 @@ pub fn load_from_file(path: &PathBuf) -> Result<Object, Box<dyn std::error::Erro
     // if no extension, then test for binary STL magic bytes 
     // if no magic bytes, then try to guess based on the first line of text in the file
 
-    let obj = obj::load_obj(file)?;
+    let obj = obj::load_obj(path, file)?;
     Ok(obj)
 }

src/importer/obj.rs

@@ -1,10 +1,10 @@
-use std::io::{BufReader, BufRead};
+use std::{io::{BufReader, BufRead}, collections::HashMap, path::PathBuf};
 
-use crate::{mesh::Vertex, aabb::AABB, importer::ObjMesh, importer::Object};
+use crate::{mesh::Vertex, aabb::AABB, importer::ObjMesh, importer::Object, importer::Material};
 
 const BUF_CAP: usize = 1024 * 128; // 128 Kilobytes
 
-enum Token {
+enum ObjToken {
     Object,
     Group,
     Vertex,
@@ -18,26 +18,141 @@ enum Token {
     MaterialUsage,
 }
 
-impl Token {
-    fn from_str<'a>(s: &'a str) -> Option<Token> {
+impl ObjToken {
+    fn from_str<'a>(s: &'a str) -> Option<ObjToken> {
         match s {
-            "o" => Some(Token::Object),
-            "g" => Some(Token::Group),
-            "v" => Some(Token::Vertex),
-            "vn" => Some(Token::Normal),
-            "vt" => Some(Token::TexCoord),
-            "f" => Some(Token::Face),
-            "p" => Some(Token::Point),
-            "l" => Some(Token::Line),
-            "s" => Some(Token::SmoothShading),
-            "mtllib" => Some(Token::MaterialLib),
-            "usemtl" => Some(Token::MaterialUsage),
+            "o" => Some(ObjToken::Object),
+            "g" => Some(ObjToken::Group),
+            "v" => Some(ObjToken::Vertex),
+            "vn" => Some(ObjToken::Normal),
+            "vt" => Some(ObjToken::TexCoord),
+            "f" => Some(ObjToken::Face),
+            "p" => Some(ObjToken::Point),
+            "l" => Some(ObjToken::Line),
+            "s" => Some(ObjToken::SmoothShading),
+            "mtllib" => Some(ObjToken::MaterialLib),
+            "usemtl" => Some(ObjToken::MaterialUsage),
             _ => None,
         }
     }
 }
 
-pub fn load_obj(file: std::fs::File) -> Result<Object, Box<dyn std::error::Error>> {
+enum MtlToken {
+    NewMaterial,
+    AmbientColor,
+    DiffuseColor,
+    SpecularColor,
+    Emissive,
+    SpecularExponent,
+    Refraction,
+    Opacity,
+    AmbientTexture,
+    DiffuseTexture,
+    SpecularTexture,
+    SpecularHighlightTexture,
+    EmissiveTexture,
+    BumpTexture,
+    DisplacementTexture,
+    DecalTexture,
+    ReflectionTexture,
+}
+
+impl MtlToken {
+    fn from_str(s: &str) -> Option<MtlToken> {
+        match s {
+            "newmtl" => Some(MtlToken::NewMaterial),
+            "Ka" => Some(MtlToken::AmbientColor),
+            "Kd" => Some(MtlToken::DiffuseColor),
+            "Ks" => Some(MtlToken::SpecularColor),
+            "Ke" => Some(MtlToken::Emissive),
+            "Ns" => Some(MtlToken::SpecularExponent),
+            "Ni" => Some(MtlToken::Refraction),
+            "d" => Some(MtlToken::Opacity),
+            "map_Ka" => Some(MtlToken::AmbientTexture),
+            "map_Kd" => Some(MtlToken::DiffuseTexture),
+            "map_Ks" => Some(MtlToken::SpecularTexture),
+            "map_Ns" => Some(MtlToken::SpecularHighlightTexture),
+            "map_Ke" => Some(MtlToken::EmissiveTexture),
+            "map_bump" => Some(MtlToken::BumpTexture),
+            "map_d" => Some(MtlToken::DisplacementTexture),
+            "decal" => Some(MtlToken::DecalTexture),
+            "refl" => Some(MtlToken::ReflectionTexture),
+            _ => None,
+        }
+    }
+}
+
+fn parse_mtl(path: &PathBuf) -> Result<HashMap<String, Material>, Box<dyn std::error::Error>> {
+    let file = std::fs::File::open(path)?;
+    let reader = BufReader::with_capacity(BUF_CAP, file);
+    let mut material_name = String::new();
+    let mut materials: HashMap<String, Material> = HashMap::new();
+    let mut material;
+    let mut ambient = glm::vec3(0.0, 0.0, 0.0);
+    let mut diffuse = glm::vec3(0.0, 0.0, 0.0);
+    let mut specular = glm::vec3(0.0, 0.0, 0.0);
+    let mut shininess = 32.0;
+    let mut opacity = 1.0;
+
+    for line in reader.lines() {
+        let line = line?;
+        // skip empty lines and comments
+        if line.is_empty() || line.chars().nth(0).is_some_and(|c| c == '#') {
+            continue;
+        }
+
+        let mut iter = line.split_ascii_whitespace();
+        let first = iter.next();
+        if let Some(token) = first {
+            match MtlToken::from_str(token) {
+                Some(MtlToken::NewMaterial) => {
+                    if !material_name.is_empty() {
+                        material = Material::new(material_name.clone(), ambient, diffuse, specular, shininess, opacity, HashMap::new());
+                        materials.insert(material_name, material);
+                    }
+
+                    material_name = iter.next().unwrap().to_string();
+                }
+                Some(MtlToken::AmbientColor) => {
+                    let r = iter.next().unwrap().parse::<f32>().unwrap();
+                    let g = iter.next().unwrap().parse::<f32>().unwrap();
+                    let b = iter.next().unwrap().parse::<f32>().unwrap();
+                    ambient = glm::vec3(r, g, b);
+                }
+                Some(MtlToken::DiffuseColor) => {
+                    let r = iter.next().unwrap().parse::<f32>().unwrap();
+                    let g = iter.next().unwrap().parse::<f32>().unwrap();
+                    let b = iter.next().unwrap().parse::<f32>().unwrap();
+                    diffuse = glm::vec3(r, g, b);
+                }
+                Some(MtlToken::SpecularColor) => {
+                    let r = iter.next().unwrap().parse::<f32>().unwrap();
+                    let g = iter.next().unwrap().parse::<f32>().unwrap();
+                    let b = iter.next().unwrap().parse::<f32>().unwrap();
+                    specular = glm::vec3(r, g, b);
+                }
+                Some(MtlToken::SpecularExponent) => {
+                    shininess = iter.next().unwrap().parse::<f32>().unwrap();
+                }
+                Some(MtlToken::Opacity) => {
+                    opacity = iter.next().unwrap().parse::<f32>().unwrap();
+                }
+                Some(MtlToken::DiffuseTexture) => {
+                    // TODO: textures
+                }
+                _ => { println!("Unhandled material token: {}", token) },
+            }
+        }
+    }
+
+    material = Material::new(material_name.clone(), ambient, diffuse, specular, shininess, opacity, HashMap::new());
+
+    materials.insert(material_name, material);
+
+    Ok(materials)
+}
+
+pub fn load_obj(obj_path: &PathBuf, file: std::fs::File) -> Result<Object, Box<dyn std::error::Error>> {
     let now = std::time::Instant::now();
     let reader = BufReader::with_capacity(BUF_CAP, file);
     let mut object_name = String::new();
@@ -49,6 +164,8 @@ pub fn load_obj(file: std::fs::File) -> Result<Object, Box<dyn std::error::Error
     let mut indices = Vec::new();
     let mut tex_coords = Vec::new();
     let mut meshes = Vec::new();
+    let mut materials: HashMap<String, Material> = HashMap::new();
+    let mut current_material: Option<Material> = None;
     let mut min_aabb = glm::vec3(std::f32::MAX, std::f32::MAX, std::f32::MAX);
     let mut max_aabb = glm::vec3(std::f32::MIN, std::f32::MIN, std::f32::MIN);
 
@@ -62,8 +179,8 @@ pub fn load_obj(file: std::fs::File) -> Result<Object, Box<dyn std::error::Error
         let mut iter = line.split_ascii_whitespace();
         let first = iter.next();
         if let Some(token) = first {
-            match Token::from_str(token) {
-                Some(Token::Object) => {
+            match ObjToken::from_str(token) {
+                Some(ObjToken::Object) => {
                     let name = {
                         if current_mesh_name.is_empty() {
                             object_name.clone()
@@ -76,6 +193,7 @@ pub fn load_obj(file: std::fs::File) -> Result<Object, Box<dyn std::error::Error
                             name,
                             vertices: vertices.clone(),
                             indices: indices.clone(),
+                            material: current_material.clone()
                         });
                     }
                     vertices.clear();
@@ -84,7 +202,7 @@ pub fn load_obj(file: std::fs::File) -> Result<Object, Box<dyn std::error::Error
 
                     object_name = iter.next().unwrap_or("").to_string();
                 }
-                Some(Token::Group) => {
+                Some(ObjToken::Group) => {
                     let name = {
                         if current_mesh_name.is_empty() {
                             object_name.clone()
@@ -97,6 +215,7 @@ pub fn load_obj(file: std::fs::File) -> Result<Object, Box<dyn std::error::Error
                             name,
                             vertices: vertices.clone(),
                             indices: indices.clone(),
+                            material: current_material.clone()
                         });
                     }
                     vertices.clear();
@@ -105,7 +224,7 @@ pub fn load_obj(file: std::fs::File) -> Result<Object, Box<dyn std::error::Error
 
                     current_mesh_name = iter.next().unwrap_or("default_mesh").to_string();
                 }
-                Some(Token::Vertex) => {
+                Some(ObjToken::Vertex) => {
                     let mut iter = iter
                         .take(3)
                         .map(|i| i.parse::<f32>().unwrap());
@@ -138,7 +257,7 @@ pub fn load_obj(file: std::fs::File) -> Result<Object, Box<dyn std::error::Error
                     }
 
                 }
-                Some(Token::Normal) => {
+                Some(ObjToken::Normal) => {
                     let mut iter = iter
                         .take(3)
                         .map(|i| i.parse::<f32>().unwrap());
@@ -147,7 +266,7 @@ pub fn load_obj(file: std::fs::File) -> Result<Object, Box<dyn std::error::Error
                     let z = iter.next().unwrap();
                     normals.push(glm::vec3(x, y, z));
                 }
-                Some(Token::TexCoord) => {
+                Some(ObjToken::TexCoord) => {
                     let mut iter = iter
                         .take(2)
                         .map(|i| i.parse::<f32>().unwrap());
@@ -155,16 +274,20 @@ pub fn load_obj(file: std::fs::File) -> Result<Object, Box<dyn std::error::Error
                     let v = iter.next().unwrap();
                     tex_coords.push(glm::vec2(u, v));
                 }
-                Some(Token::Face) => {
+                Some(ObjToken::Face) => {
                     // TODO: vertex indices can be negative
 
                     let face = iter.collect::<Vec<_>>();
                     let mut calculated_normal = glm::vec3(0.0, 0.0, 0.0);
 
                     if normals.is_empty() {
+                        let part0 = face[0].split("/").next().unwrap();
+                        let part1 = face[1].split("/").next().unwrap();
+                        let part2 = face[2].split("/").next().unwrap();
+
                         calculated_normal = glm::normalize(glm::cross(
-                            temp_vertices[face[1].parse::<i32>().unwrap() as usize - 1] - temp_vertices[face[0].parse::<i32>().unwrap() as usize - 1],
-                            temp_vertices[face[2].parse::<i32>().unwrap() as usize - 1] - temp_vertices[face[0].parse::<i32>().unwrap() as usize - 1]
+                            temp_vertices[part1.parse::<i32>().unwrap() as usize - 1] - temp_vertices[part0.parse::<i32>().unwrap() as usize - 1],
+                            temp_vertices[part2.parse::<i32>().unwrap() as usize - 1] - temp_vertices[part0.parse::<i32>().unwrap() as usize - 1]
                         ));
                     }
 
@@ -178,7 +301,7 @@ pub fn load_obj(file: std::fs::File) -> Result<Object, Box<dyn std::error::Error
                                 normal: *normals.get(normal as usize).unwrap(),
                                 tex_coords: glm::vec2(0.0, 0.0)
                             });
-                        } else if vert.contains("/") {
+                        } else if vert.matches("/").count() == 2 {
                             let mut it = vert.split("/");
                             let vertex = it.next().unwrap().parse::<i32>().unwrap() - 1;
                             let t_coords = it.next().unwrap().parse::<i32>().unwrap() - 1;
@@ -188,6 +311,15 @@ pub fn load_obj(file: std::fs::File) -> Result<Object, Box<dyn std::error::Error
                                 normal: *normals.get(normal as usize).unwrap(),
                                 tex_coords: *tex_coords.get(t_coords as usize).unwrap()
                             });
+                        } else if vert.matches("/").count() == 1 {
+                            let mut it = vert.split("/");
+                            let vertex = it.next().unwrap().parse::<i32>().unwrap() - 1;
+                            let t_coords = it.next().unwrap().parse::<i32>().unwrap() - 1;
+                            vertices.push(Vertex{
+                                position: *temp_vertices.get(vertex as usize).unwrap(),
+                                normal: calculated_normal,
+                                tex_coords: *tex_coords.get(t_coords as usize).unwrap()
+                            });
                         } else {
                             let vert = vert.parse::<i32>().unwrap() - 1;
                             vertices.push(Vertex{
@@ -207,15 +339,48 @@ pub fn load_obj(file: std::fs::File) -> Result<Object, Box<dyn std::error::Error
 
                     indices_counter += face.len() as u32;
                 }
-                Some(Token::MaterialLib) => {
-                    // TODO: handle material file
+                Some(ObjToken::MaterialLib) => {
+                    let material_path = obj_path.parent().unwrap().join(iter.next().unwrap_or(""));
+                    let new_materials = parse_mtl(&material_path);
+                    match new_materials {
+                        Ok(m) => {
+                            materials.extend(m);
+                        },
+                        Err(e) => {
+                            eprintln!("Failed to parse mtl file {:?}: {}", material_path, e);
+                        }
+                    }
                 }
-                Some(Token::MaterialUsage) => {
-                    // TODO: handle material usage
-                    // this can be used multiple times before f is mentioned
-                    // to apply the material to those faces after it
+                Some(ObjToken::MaterialUsage) => {
+                    // Split into meshes by material usage
+                    let name = {
+                        if current_mesh_name.is_empty() && !object_name.is_empty() {
+                            object_name.clone()
+                        } else if !current_mesh_name.is_empty() {
+                            current_mesh_name.clone()
+                        } else {
+                            "default_mesh".to_string()
+                        }
+                    };
+                    if !vertices.is_empty() {
+                        meshes.push(ObjMesh{
+                            name,
+                            vertices: vertices.clone(),
+                            indices: indices.clone(),
+                            material: current_material.clone()
+                        });
+                    }
+                    vertices.clear();
+                    indices.clear();
+                    indices_counter = 0;
+
+                    let mat_name = iter.next().unwrap_or("").to_string();
+                    current_material = materials.get(&mat_name).cloned();
                 }
-                _ => {},
+                Some(ObjToken::Line) | Some(ObjToken::Point) => {
+                    // we don't handle lines or points
+                }
+                _ => { println!("Unhandled obj token: {}", token) },
             }
         }
     }
@@ -236,6 +401,7 @@ pub fn load_obj(file: std::fs::File) -> Result<Object, Box<dyn std::error::Error
         name: mesh_name,
         vertices: vertices.clone(),
         indices: indices.clone(),
+        material: current_material
     });
 
     let aabb = AABB::new(min_aabb, max_aabb);
@@ -243,6 +409,6 @@ pub fn load_obj(file: std::fs::File) -> Result<Object, Box<dyn std::error::Error
     Ok(Object{
         name: object_name,
         meshes,
-        aabb
+        aabb,
     })
 }

src/mesh.rs

@@ -1,7 +1,7 @@
 use glad_gl::gl;
 use anyhow::Result;
 
-use crate::{shader::Shader, utils};
+use crate::{shader::Shader, utils, importer::Material};
 
 fn decompose_mat(matrix: &mut glm::Mat4) -> (glm::Vec3, glm::Vec3, glm::Vec3) {
     let pos = glm::vec3(matrix.c0.w, matrix.c1.w, matrix.c2.w);
@@ -89,7 +89,7 @@ pub struct Mesh {
 }
 
 impl Mesh {
-    pub fn new(name: &str, vertices: Vec<Vertex>, indices: Vec<u32>) -> Mesh {
+    pub fn new(name: &str, vertices: Vec<Vertex>, indices: Vec<u32>, material: Option<Material>) -> Mesh {
         let mut vao = 0;
         let mut vbo = 0;
         let mut ebo = 0;
@@ -129,7 +129,7 @@ impl Mesh {
             vertices,
             indices,
             // textures,
-            material: Material::new("default".to_string(), glm::vec3(0.4, 0.4, 0.4), glm::vec3(0.7, 0.7, 0.7), glm::vec3(0.1, 0.1, 0.1), 32.0),
+            material: material.unwrap_or_default(),
             vbo,
             vao,
             ebo,
@@ -151,10 +151,10 @@ impl Mesh {
         let model_mat = glm::ext::translate(&model_mat, glm::vec3(self.position.x, self.position.y, self.position.z));
         shader.set_mat4fv("model", &model_mat);
 
-        shader.set_3fv("material.ambient", self.material.ambient);
-        shader.set_3fv("material.diffuse", self.material.diffuse);
-        shader.set_3fv("material.specular", self.material.specular);
-        shader.set_float("material.shininess", self.material.shininess);
+        shader.set_3fv("material.ambient", self.material.ambient_color);
+        shader.set_3fv("material.diffuse", self.material.diffuse_color);
+        shader.set_3fv("material.specular", self.material.specular_color);
+        shader.set_float("material.shininess", self.material.specular_exponent);
 
         // for i in 0..self.textures.len() {
         //     unsafe {
@@ -248,29 +248,3 @@ impl Texture {
     }
 }
 
-#[derive(Debug)]
-pub struct Material {
-    pub name: String,
-    pub ambient: glm::Vec3,
-    pub diffuse: glm::Vec3,
-    pub specular: glm::Vec3,
-    pub shininess: f32,
-}
-
-impl Material {
-    pub fn new(name: String, ambient: glm::Vec3, diffuse: glm::Vec3, specular: glm::Vec3, shininess: f32) -> Self {
-        Material {
-            name,
-            ambient,
-            diffuse,
-            specular,
-            shininess,
-        }
-    }
-}
-
-impl std::fmt::Display for Material {
-    fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
-        write!(f, "Ambient: {:?}\nDiffuse: {:?}\nSpecular: {:?}\nShininess: {}", self.ambient, self.diffuse, self.specular, self.shininess)
-    }
-}

src/model.rs

@@ -1,10 +1,8 @@
-use std::path::PathBuf;
-
-use crate::{mesh::{Mesh, Vertex, Texture, Material, apply_rotation}, shader::Shader, utils, ui::ui, log, aabb, importer};
-
 use russimp;
 use anyhow::{Result, anyhow};
 
+use crate::{mesh::{Mesh, Vertex, Texture, apply_rotation}, shader::Shader, utils, ui::ui, log, aabb, importer};
+
 const SUPPORTED_TEXTURE_TYPES: [russimp::material::TextureType; 2] = [
     russimp::material::TextureType::Diffuse,
     russimp::material::TextureType::Specular,
@@ -285,7 +283,7 @@ impl Model {
         let mut meshes = Vec::new();
 
         for mesh in obj.meshes.into_iter() {
-            meshes.push(Mesh::new(&mesh.name, mesh.vertices, mesh.indices));
+            meshes.push(Mesh::new(&mesh.name, mesh.vertices, mesh.indices, mesh.material));
         }
 
         Model {