support/camera.rs

   1 extern crate glutin;
   2
   3 use std::f32;
   4 use std::ops::Add;
   5 use std::ops::AddAssign;
   6 use std::ops::Sub;
   7 use std::ops::Mul;
   8
   9 //use glutin::Event;
  10 //use glutin::VirtualKeyCode;
  11
  12 #[derive(Default, PartialEq, Debug, Clone, Copy)]
  13 pub struct Vec3 (f32, f32, f32);
  14
  15 impl Add for Vec3 {
  16     type Output = Vec3;
  17     fn add(self, other: Vec3) -> Vec3 {
  18         Vec3(self.0 + other.0, self.1 + other.1, self.2 + other.2)
  19     }
  20 }
  21
  22 impl AddAssign for Vec3 {
  23     fn add_assign(&mut self, other: Vec3) {
  24         *self = Vec3(self.0 + other.0, self.1 + other.1, self.2 + other.2)
  25     }
  26 }
  27
  28 impl Sub for Vec3 {
  29     type Output = Vec3;
  30     fn sub(self, other: Vec3) -> Vec3 {
  31         Vec3(self.0 - other.0, self.1 - other.1, self.2 - other.2)
  32     }
  33 }
  34
  35 impl Mul<f32> for Vec3 {
  36     type Output = Vec3;
  37     fn mul(self, f: f32) -> Vec3 {
  38         Vec3(self.0 * f, self.1 * f, self.2 * f)
  39     }
  40 }
  41
  42 #[derive(Default)]
  43 pub struct CameraState {
  44     aspect_ratio: f32,
  45     pos: Vec3,
  46     dir: Vec3,
  47
  48     moving_up: bool,
  49     moving_left: bool,
  50     moving_down: bool,
  51     moving_right: bool,
  52     moving_forward: bool,
  53     moving_backward: bool,
  54     turning_up: bool,
  55     turning_left: bool,
  56     turning_down: bool,
  57     turning_right: bool,
  58 }
  59
  60 fn norm(v: &Vec3) -> Vec3 {
  61     let len = (v.0 * v.0 + v.1 * v.1 + v.2 * v.2).sqrt();
  62     Vec3(v.0 / len, v.1 / len, v.2 / len)
  63 }
  64
  65 impl CameraState {
  66     pub fn new() -> CameraState {
  67         CameraState {
  68             aspect_ratio: 1024.0 / 768.0,
  69             pos: Vec3(0.0, 0.0, 0.0),
  70             dir: Vec3(0.0, 0.0, 1.0),
  71             .. Default::default()
  72         }
  73     }
  74
  75     pub fn set_pos(&mut self, pos: Vec3) {
  76         self.pos = pos;
  77     }
  78
  79     pub fn set_dir(&mut self, dir: Vec3) {
  80         self.dir = dir;
  81     }
  82
  83     pub fn get_perspective(&self) -> [[f32; 4]; 4] {
  84         let fov: f32 = 3.141592 / 2.0;
  85         let zfar = 1024.0;
  86         let znear = 0.1;
  87
  88         let f = 1.0 / (fov / 2.0).tan();
  89
  90         // note: remember that this is column-major, so the lines of code are actually columns
  91         [
  92             [f / self.aspect_ratio,    0.0,              0.0              ,   0.0],
  93             [         0.0         ,     f ,              0.0              ,   0.0],
  94             [         0.0         ,    0.0,  (zfar+znear)/(zfar-znear)    ,   1.0],
  95             [         0.0         ,    0.0, -(2.0*zfar*znear)/(zfar-znear),   0.0],
  96         ]
  97     }
  98
  99
 100     pub fn get_view(&self) -> [[f32; 4]; 4] {
 101         let f = norm(&self.dir);
 102
 103         let up = Vec3(0.0, 1.0, 0.0);
 104
 105         let s = Vec3(f.1 * up.2 - f.2 * up.1,
 106                      f.2 * up.0 - f.0 * up.2,
 107                      f.0 * up.1 - f.1 * up.0);
 108         let sn = norm(&s);
 109
 110         let u = (sn.1 * f.2 - sn.2 * f.1,
 111                  sn.2 * f.0 - sn.0 * f.2,
 112                  sn.0 * f.1 - sn.1 * f.0);
 113
 114         let p = (-self.pos.0 * s.0 - self.pos.1 * s.1 - self.pos.2 * s.2,
 115                  -self.pos.0 * u.0 - self.pos.1 * u.1 - self.pos.2 * u.2,
 116                  -self.pos.0 * f.0 - self.pos.1 * f.1 - self.pos.2 * f.2);
 117
 118         // note: remember that this is column-major, so the lines of code are actually columns
 119         [
 120             [sn.0, u.0, f.0, 0.0],
 121             [sn.1, u.1, f.1, 0.0],
 122             [sn.2, u.2, f.2, 0.0],
 123             [p.0,  p.1, p.2, 1.0],
 124         ]
 125     }
 126
 127     pub fn update(&mut self) {
 128         let f = norm(&self.dir);
 129
 130         let up = Vec3(0.0, 1.0, 0.0);
 131
 132         let s = Vec3(f.1 * up.2 - f.2 * up.1,
 133                      f.2 * up.0 - f.0 * up.2,
 134                      f.0 * up.1 - f.1 * up.0);
 135
 136         let s = norm(&s);
 137
 138         let u = Vec3(s.1 * f.2 - s.2 * f.1,
 139                      s.2 * f.0 - s.0 * f.2,
 140                      s.0 * f.1 - s.1 * f.0);
 141
 142         if self.moving_up {
 143             self.pos += u * 0.01;
 144         }
 145         if self.moving_left {
 146             self.pos.0 -= s.0 * 0.01;
 147             self.pos.1 -= s.1 * 0.01;
 148             self.pos.2 -= s.2 * 0.01;
 149         }
 150         if self.moving_down {
 151             self.pos.0 -= u.0 * 0.01;
 152             self.pos.1 -= u.1 * 0.01;
 153             self.pos.2 -= u.2 * 0.01;
 154         }
 155         if self.moving_right {
 156             self.pos += s * 0.01;
 157         }
 158         if self.moving_forward {
 159             self.pos += f * 0.01;
 160         }
 161         if self.moving_backward {
 162             self.pos.0 -= f.0 * 0.01;
 163             self.pos.1 -= f.1 * 0.01;
 164             self.pos.2 -= f.2 * 0.01;
 165         }
 166         if self.turning_left {
 167             let a: f32 = -0.05;
 168             self.dir = Vec3(f.0 * a.cos() + f.2 * a.sin(), f.1, - f.0 * a.sin() + f.2 * a.cos());
 169         }
 170         if self.turning_right {
 171             let a: f32 = 0.05;
 172             self.dir = Vec3(f.0 * a.cos() + f.2 * a.sin(), f.1, - f.0 * a.sin() + f.2 * a.cos());
 173         }
 174         if self.turning_up {
 175             let a: f32 = -0.05;
 176             self.dir = Vec3(f.0, f.1 * a.cos() - f.2 * a.sin(), f.1 * a.sin() + f.2 * a.cos());
 177         }
 178         if self.turning_down {
 179             let a: f32 = 0.05;
 180             self.dir = Vec3(f.0, f.1 * a.cos() - f.2 * a.sin(), f.1 * a.sin() + f.2 * a.cos());
 181         }
 182         //println!("camera_pos = {:?}", self.pos);
 183         //println!("camera_dir = {:?}", self.dir);
 184     }
 185
 186     pub fn process_input(&mut self, event: &glutin::Event) {
 187         match event {
 188             &glutin::Event::KeyboardInput(glutin::ElementState::Pressed, _, Some(glutin::VirtualKeyCode::Up)) => {
 189                 self.moving_up = true;
 190             },
 191             &glutin::Event::KeyboardInput(glutin::ElementState::Released, _, Some(glutin::VirtualKeyCode::Up)) => {
 192                 self.moving_up = false;
 193             },
 194             &glutin::Event::KeyboardInput(glutin::ElementState::Pressed, _, Some(glutin::VirtualKeyCode::Down)) => {
 195                 self.moving_down = true;
 196             },
 197             &glutin::Event::KeyboardInput(glutin::ElementState::Released, _, Some(glutin::VirtualKeyCode::Down)) => {
 198                 self.moving_down = false;
 199             },
 200             &glutin::Event::KeyboardInput(glutin::ElementState::Pressed, _, Some(glutin::VirtualKeyCode::Left)) => {
 201                 self.moving_left = true;
 202             },
 203             &glutin::Event::KeyboardInput(glutin::ElementState::Released, _, Some(glutin::VirtualKeyCode::Left)) => {
 204                 self.moving_left = false;
 205             },
 206             &glutin::Event::KeyboardInput(glutin::ElementState::Pressed, _, Some(glutin::VirtualKeyCode::Right)) => {
 207                 self.moving_right = true;
 208             },
 209             &glutin::Event::KeyboardInput(glutin::ElementState::Released, _, Some(glutin::VirtualKeyCode::Right)) => {
 210                 self.moving_right = false;
 211             },
 212             &glutin::Event::KeyboardInput(glutin::ElementState::Pressed, _, Some(glutin::VirtualKeyCode::A)) => {
 213                 self.turning_left = true;
 214             },
 215             &glutin::Event::KeyboardInput(glutin::ElementState::Released, _, Some(glutin::VirtualKeyCode::A)) => {
 216                 self.turning_left = false;
 217             },
 218             &glutin::Event::KeyboardInput(glutin::ElementState::Pressed, _, Some(glutin::VirtualKeyCode::D)) => {
 219                 self.turning_right = true;
 220             },
 221             &glutin::Event::KeyboardInput(glutin::ElementState::Released, _, Some(glutin::VirtualKeyCode::D)) => {
 222                 self.turning_right = false;
 223             },
 224             &glutin::Event::KeyboardInput(glutin::ElementState::Pressed, _, Some(glutin::VirtualKeyCode::W)) => {
 225                 self.moving_forward = true;
 226             },
 227             &glutin::Event::KeyboardInput(glutin::ElementState::Released, _, Some(glutin::VirtualKeyCode::W)) => {
 228                 self.moving_forward = false;
 229             },
 230             &glutin::Event::KeyboardInput(glutin::ElementState::Pressed, _, Some(glutin::VirtualKeyCode::S)) => {
 231                 self.moving_backward = true;
 232             },
 233             &glutin::Event::KeyboardInput(glutin::ElementState::Released, _, Some(glutin::VirtualKeyCode::S)) => {
 234                 self.moving_backward = false;
 235             },
 236             &glutin::Event::KeyboardInput(glutin::ElementState::Pressed, _, Some(glutin::VirtualKeyCode::R)) => {
 237                 self.turning_up = true;
 238             },
 239             &glutin::Event::KeyboardInput(glutin::ElementState::Released, _, Some(glutin::VirtualKeyCode::R)) => {
 240                 self.turning_up = false;
 241             },
 242             &glutin::Event::KeyboardInput(glutin::ElementState::Pressed, _, Some(glutin::VirtualKeyCode::F)) => {
 243                 self.turning_down = true;
 244             },
 245             &glutin::Event::KeyboardInput(glutin::ElementState::Released, _, Some(glutin::VirtualKeyCode::F)) => {
 246                 self.turning_down = false;
 247             },
 248             _ => {}
 249         }
 250     }
 251 }