Starting to work on frustums

src/camera.rs

@@ -1,6 +1,22 @@
 //! This module contains everything to deal with cameras.
 
 use math::vector::Vector3;
+use math::frustum::Frustum;
+
+/// Multiplies two matrices 4x4
+fn multiply_matrices(a: [[f32; 4]; 4], b: [[f32; 4]; 4]) -> [[f32; 4]; 4] {
+    let mut res = [[0.0; 4]; 4];
+
+    for i in 0..4 {
+        for j in 0..4 {
+            for k in 0..4 {
+                res[i][j] += a[i][k] + b[k][j];
+            }
+        }
+    }
+
+    res
+}
 
 /// The trait that a render camera should implement.
 ///
@@ -11,7 +27,17 @@ pub trait RenderCamera {
     fn get_view_matrix(&self) -> [[f32; 4]; 4];
 
     /// Returns the perspective matrix of the camera.
-    fn get_perspective_matrix(&self) -> [[f32; 4]; 4] ;
+    fn get_perspective_matrix(&self) -> [[f32; 4]; 4];
+
+    /// Returns the product of the perspective matrix and the view matrix.
+    fn get_model_view_matrix(&self) -> [[f32; 4]; 4] {
+        multiply_matrices(self.get_perspective_matrix(), self.get_view_matrix())
+    }
+
+    /// Returns the frustum of the camera.
+    fn frustum(&self) -> Frustum {
+        Frustum::from_matrix(&self.get_model_view_matrix())
+    }
 
 }
 

src/controls.rs

@@ -226,7 +226,7 @@ impl FirstPersonControls {
     }
 
     /// Updates the camera according to the state of the controls.
-    fn update_camera(&self, camera: &mut Camera) {
+    pub fn update_camera(&self, camera: &mut Camera) {
         camera.position = self.position;
         camera.target = self.position + self.forward;
     }

src/math/frustum.rs

@@ -0,0 +1,67 @@
+//! Module containing the frustum struct.
+//!
+//! The frustum is the field of view of a camera. It allows you to make computation to know what is
+//! visible or not in an efficient manner, though it doesn't take occlusions into account.
+
+use math::vector::Vector3;
+use math::plane::Plane;
+use math::bounding_box::BoundingBox3;
+
+/// Struct containing the 6 planes of a 3D camera.
+#[derive(Copy, Clone)]
+pub struct Frustum {
+    /// The planes of the frustum.
+    planes: [Plane; 6],
+}
+
+impl Frustum {
+    /// Creates a frustum from the matrix of a camera.
+    ///
+    /// This is *ahem...* slightly inspired from THREE.js Frustum
+    pub fn from_matrix(m: &[[f32; 4]; 4]) -> Frustum {
+
+        let m0  = m[0][0]; let m1  = m[0][1]; let m2  = m[0][2]; let m3  = m[0][3];
+        let m4  = m[1][0]; let m5  = m[1][1]; let m6  = m[1][2]; let m7  = m[1][3];
+        let m8  = m[2][0]; let m9  = m[2][1]; let m10 = m[2][2]; let m11 = m[2][3];
+        let m12 = m[3][0]; let m13 = m[3][1]; let m14 = m[3][2]; let m15 = m[3][3];
+
+        Frustum {
+            planes: [
+                Plane::from_coordinates(m3 - m0, m7 - m4, m11 - m8,  m15 - m12),
+                Plane::from_coordinates(m3 + m0, m7 + m4, m11 + m8,  m15 + m12),
+                Plane::from_coordinates(m3 + m1, m7 + m5, m11 + m9,  m15 + m13),
+                Plane::from_coordinates(m3 - m1, m7 - m5, m11 - m9,  m15 - m13),
+                Plane::from_coordinates(m3 - m2, m7 - m6, m11 - m10, m15 - m14),
+                Plane::from_coordinates(m3 + m2, m7 + m6, m11 + m10, m15 + m14),
+            ],
+        }
+    }
+
+    /// Returns true if the intersection of the frustum and the bounding box is not empty.
+    pub fn intersects_box(&self, bbox: BoundingBox3<f32>) -> bool {
+
+        use num::Zero;
+
+        let mut p1 = Vector3::<f32>::zero();
+        let mut p2 = Vector3::<f32>::zero();
+
+        for plane in &self.planes {
+
+            p1[0] = if plane.normal().x() > 0.0 { bbox.min().x() } else { bbox.max().x() };
+            p2[0] = if plane.normal().x() > 0.0 { bbox.max().x() } else { bbox.min().x() };
+            p1[1] = if plane.normal().y() > 0.0 { bbox.min().y() } else { bbox.max().y() };
+            p2[1] = if plane.normal().y() > 0.0 { bbox.max().y() } else { bbox.min().y() };
+            p1[2] = if plane.normal().z() > 0.0 { bbox.min().z() } else { bbox.max().z() };
+            p2[2] = if plane.normal().z() > 0.0 { bbox.max().z() } else { bbox.min().z() };
+
+            let d1 = plane.distance_to_point(p1);
+            let d2 = plane.distance_to_point(p2);
+
+            if d1 < 0.0 && d2 < 2.0 {
+                return false;
+            }
+        }
+
+        true
+    }
+}

src/math/mod.rs

@@ -2,6 +2,8 @@
 
 pub mod vector;
 pub mod bounding_box;
+pub mod plane;
+pub mod frustum;
 
 use std::ops::{Add, AddAssign, Sub, SubAssign, Mul, MulAssign, Div, DivAssign};
 use num::{Zero, One};

src/math/plane.rs

@@ -0,0 +1,65 @@
+//! Module containing the plane struct.
+
+use math::vector::Vector3;
+
+/// A 3D plane.
+#[derive(Copy, Clone)]
+pub struct Plane {
+    /// The normal of the plane.
+    normal: Vector3<f32>,
+
+    /// The constant, offset of the plane from the origin.
+    constant: f32,
+}
+
+impl Plane {
+    /// Creates a new plane from its normal and its constant.
+    pub fn from_coordinates(a: f32, b: f32, c: f32, w: f32) -> Plane {
+        let mut p = Plane {
+            normal: Vector3::new(a, b, c),
+            constant: w,
+        };
+        p.normalize();
+        p
+    }
+
+    /// Creates a new plane from its normal and its constant.
+    pub fn from_normal_and_constant(normal: Vector3<f32>, constant: f32) -> Plane {
+        Plane::from_coordinates(normal.x(), normal.y(), normal.z(), constant)
+    }
+
+    /// Creates a new plane from its normal and a point of the plane.
+    pub fn from_normal_and_point(normal: Vector3<f32>, point: Vector3<f32>) -> Plane {
+        Plane::from_normal_and_constant(normal, - point.dot(normal))
+    }
+
+
+    /// Creates a new plane from three points.
+    pub fn from_points(p1: Vector3<f32>, p2: Vector3<f32>, p3: Vector3<f32>) -> Plane {
+        let p1p2 = p2 - p1;
+        let p1p3 = p3 - p1;
+        Plane::from_normal_and_point(p1p2.cross_product(p1p3), p1)
+    }
+
+    /// Normalizes the plane.
+    pub fn normalize(&mut self) {
+        let normal_inverse = 1.0 / self.normal.norm();
+        self.normal *= normal_inverse;
+        self.constant *= normal_inverse;
+    }
+
+    /// Returns the normal of the plane.
+    pub fn normal(&self) -> Vector3<f32> {
+        self.normal
+    }
+
+    /// Returns the constant of the plane.
+    pub fn constant(&self) -> f32 {
+        self.constant
+    }
+
+    /// Returns the distance between the plane and the point.
+    pub fn distance_to_point(&self, point: Vector3<f32>) -> f32 {
+        self.normal.dot(point) + self.constant
+    }
+}

src/renderer.rs

@@ -4,6 +4,8 @@ use std::cell::Ref;
 use std::borrow::Cow;
 
 use image;
+use image::{ImageBuffer, Rgba};
+
 use glium::texture::{RawImage2d, SrgbTexture2d, Texture2dDataSink};
 use glium::{Frame, Display, Surface, Program, DrawParameters, Depth, VertexBuffer};
 use glium::{Rect, BlitTarget};
@@ -88,9 +90,14 @@ impl Renderer {
     /// Creates a SrgbTexture from a path to an image.
     pub fn make_texture(&self, path: &str) -> SrgbTexture2d {
         let image = image::open(path).unwrap().to_rgba();
-        let dimensions = image.dimensions();
-        let image = RawImage2d::from_raw_rgba_reversed(&image.into_raw(), dimensions);
-        SrgbTexture2d::new(&self.display, image).ok().unwrap()
+        self.make_texture_from_buffer(image)
+    }
+
+    /// Creates a SrgbTexture from an image buffer.
+    pub fn make_texture_from_buffer(&self, buffer: ImageBuffer<Rgba<u8>, Vec<u8>>) -> SrgbTexture2d {
+        let dimensions = buffer.dimensions();
+        let buffer = RawImage2d::from_raw_rgba_reversed(&buffer.into_raw(), dimensions);
+        SrgbTexture2d::new(&self.display, buffer).ok().unwrap()
     }
 
     /// Creates a 1x1 SrgbTexture with the color passed as parameter.

src/scene.rs

@@ -2,13 +2,13 @@
 
 use std::slice::{Iter, IterMut};
 use std::vec::IntoIter;
-use std::rc::Rc;
+use std::sync::Arc;
 use std::cell::RefCell;
 use model::Model;
 
 /// Represents a 3D scene with models.
 pub struct Scene {
-    models: Vec<Rc<RefCell<Model>>>,
+    models: Vec<Arc<RefCell<Model>>>,
 }
 
 impl Scene {
@@ -20,29 +20,29 @@ impl Scene {
     }
 
     /// Adds a model to the scene.
-    pub fn push(&mut self, model: Rc<RefCell<Model>>) {
+    pub fn push(&mut self, model: Arc<RefCell<Model>>) {
         self.models.push(model);
     }
 
-    /// Converts the model to a Rc<RefCell<Model>> and adds it to the scene.
+    /// Converts the model to a Arc<RefCell<Model>> and adds it to the scene.
     pub fn emplace(&mut self, model: Model) {
-        self.models.push(Rc::new(RefCell::new(model)));
+        self.models.push(Arc::new(RefCell::new(model)));
     }
 
     /// Returns an iterator to the models of the scene.
-    pub fn iter(&self) -> Iter<Rc<RefCell<Model>>> {
+    pub fn iter(&self) -> Iter<Arc<RefCell<Model>>> {
         self.models.iter()
     }
 
     /// Returns a mutable iterator to the model of the scene.
-    pub fn iter_mut(&mut self) -> IterMut<Rc<RefCell<Model>>> {
+    pub fn iter_mut(&mut self) -> IterMut<Arc<RefCell<Model>>> {
         self.models.iter_mut()
     }
 }
 
 impl IntoIterator for Scene {
-    type IntoIter = IntoIter<Rc<RefCell<Model>>>;
-    type Item = Rc<RefCell<Model>>;
+    type IntoIter = IntoIter<Arc<RefCell<Model>>>;
+    type Item = Arc<RefCell<Model>>;
 
     fn into_iter(self) -> Self::IntoIter {
         self.models.into_iter()
@@ -52,7 +52,7 @@ impl IntoIterator for Scene {
 impl From<Vec<Model>> for Scene {
     fn from(input: Vec<Model>) -> Scene {
         Scene {
-            models: input.into_iter().map(|x| Rc::new(RefCell::new(x))).collect(),
+            models: input.into_iter().map(|x| Arc::new(RefCell::new(x))).collect(),
         }
     }
 }