eleni.mutantstargoat.com Git - demo/blob - src/camera.cc

   1 #include <math.h>
   2
   3 #include <gmath/gmath.h>
   4
   5 #include "camera.h"
   6 #include "state_manager.h"
   7
   8 Camera::Camera() {}
   9 Camera::~Camera() {}
  10
  11 void Camera::use() const
  12 {
  13         state_manager.set_state("st_view_matrix", get_view_matrix());
  14 }
  15
  16 OrbitCamera::OrbitCamera()
  17 {
  18         phi = theta = distance = 0;
  19 }
  20
  21 OrbitCamera::~OrbitCamera() {}
  22
  23 void OrbitCamera::set_orbit_params(float theta, float phi, float distance)
  24 {
  25         this->phi = phi;
  26         this->theta = theta;
  27         this->distance = distance;
  28 }
  29
  30 Mat4 OrbitCamera::get_view_matrix() const
  31 {
  32         Mat4 view_matrix;
  33         view_matrix.translation(-position);
  34         view_matrix.rotate_y(theta * (float)M_PI / 180);
  35         view_matrix.rotate_x(phi * (float)M_PI / 180);
  36         view_matrix.translate(Vec3(0, 0, -distance));
  37
  38         return view_matrix;
  39 }
  40
  41 Mat4 calc_projection_matrix(float fov_deg, float aspect, float n, float f)
  42 {
  43         float fov = fov_deg / 180 * M_PI;
  44
  45         float tmp;
  46         tmp = 1 / tan(fov / 2.0);
  47
  48         /* near - far clipping planes */
  49         float range = n - f;
  50
  51         Mat4 pmat = Mat4(
  52                         tmp/aspect,     0,              0,                                      0,
  53                         0,                              tmp,    0,                                      0,
  54                         0,                              0,      (f + n) / range,        -1,
  55                         0,                              0,              2 * n * f / range,      0
  56                     );
  57
  58         return pmat;
  59 }
  60
  61 void OrbitCamera::set_position(float x, float y, float z)
  62 {
  63         position.x = x;
  64         position.y = y;
  65         position.z = z;
  66 }