source/render/camera.cpp

   1 #include <cmath>
   2 #include "camera.h"
   3 #include "matrix.h"
   4
   5 using namespace std;
   6
   7 namespace Msp {
   8 namespace GL {
   9
  10 Camera::Camera():
  11         fov(Geometry::Angle<float>::from_turns(0.125)),
  12         height(0),
  13         aspect(4.0/3.0),
  14         clip_near(0.1),
  15         clip_far(10),
  16         frustum_x(0),
  17         frustum_y(0),
  18         position(0, 0, 0),
  19         look_dir(0, 0, -1),
  20         up_dir(0, 1, 0)
  21 {
  22         update_projection_matrix();
  23         update_object_matrix();
  24 }
  25
  26 void Camera::set_field_of_view(const Geometry::Angle<float> &f)
  27 {
  28         fov = f;
  29         update_projection_matrix();
  30 }
  31
  32 void Camera::set_orthographic(float w, float h)
  33 {
  34         fov = Geometry::Angle<float>::zero();
  35         height = h;
  36         if(w)
  37                 aspect = w/h;
  38         update_projection_matrix();
  39 }
  40
  41 void Camera::set_aspect_ratio(float a)
  42 {
  43         aspect = a;
  44         update_projection_matrix();
  45 }
  46
  47 void Camera::set_depth_clip(float n, float f)
  48 {
  49         clip_near = n;
  50         clip_far = f;
  51         update_projection_matrix();
  52 }
  53
  54 void Camera::set_frustum_axis(float x, float y)
  55 {
  56         frustum_x = x;
  57         frustum_y = y;
  58         update_projection_matrix();
  59 }
  60
  61 void Camera::set_frustum_rotation(const Geometry::Angle<float> &r)
  62 {
  63         rotate = r;
  64         update_projection_matrix();
  65 }
  66
  67 void Camera::set_position(const Vector3 &p)
  68 {
  69         position = p;
  70         update_object_matrix();
  71 }
  72
  73 void Camera::set_look_direction(const Vector3 &l)
  74 {
  75         look_dir = normalize(l);
  76         update_object_matrix();
  77 }
  78
  79 void Camera::look_at(const Vector3 &p)
  80 {
  81         set_look_direction(p-position);
  82 }
  83
  84 void Camera::set_up_direction(const Vector3 &u)
  85 {
  86         up_dir = normalize(u);
  87         update_object_matrix();
  88 }
  89
  90 void Camera::set_object_matrix(const Matrix &m)
  91 {
  92         position = m.column(3).slice<3>(0);
  93         look_dir = normalize(-m.column(2).slice<3>(0));
  94         up_dir = normalize(m.column(1).slice<3>(0));
  95         update_object_matrix();
  96 }
  97
  98 Vector3 Camera::project(const Vector4 &p) const
  99 {
 100         Vector4 r = proj_matrix*(view_matrix*p);
 101         return r.slice<3>(0)/r.w;
 102 }
 103
 104 Vector3 Camera::project(const Vector3 &p) const
 105 {
 106         return project(Vector4(p.x, p.y, p.z, 1.0));
 107 }
 108
 109 Vector4 Camera::unproject(const Vector4 &p) const
 110 {
 111         Vector4 r = invert(proj_matrix)*Vector4(p.x, p.y, p.z, 1.0f);
 112         r = matrix*Vector4(r.x/r.w, r.y/r.w, r.z/r.w, p.w);
 113         return r;
 114 }
 115
 116 Vector3 Camera::unproject(const Vector3 &p) const
 117 {
 118         return unproject(Vector4(p.x, p.y, p.z, 1.0f)).slice<3>(0);
 119 }
 120
 121 void Camera::update_projection_matrix()
 122 {
 123         float frustum_h = (fov!=Geometry::Angle<float>::zero() ? tan(fov/2.0f)*clip_near : height/2);
 124         float frustum_w = frustum_h*aspect;
 125         float left = frustum_w*(frustum_x-1.0f);
 126         float right = frustum_w*(frustum_x+1.0f);
 127         float bottom = frustum_h*(frustum_y-1.0f);
 128         float top = frustum_h*(frustum_y+1.0f);
 129         if(fov>Geometry::Angle<float>::zero())
 130                 proj_matrix = Matrix::frustum(left, right, bottom, top, clip_near, clip_far);
 131         else
 132                 proj_matrix = Matrix::ortho(left, right, bottom, top, clip_near, clip_far);
 133         proj_matrix = Matrix::rotation(rotate, Vector3(0, 0, 1))*proj_matrix;
 134
 135         shdata.uniform("clip_eye_matrix", proj_matrix);
 136         shdata.uniform("eye_clip_matrix", invert(proj_matrix));
 137 }
 138
 139 void Camera::update_object_matrix()
 140 {
 141         Vector3 right_dir = normalize(cross(look_dir, up_dir));
 142         Vector4 columns[4];
 143         columns[0] = compose(right_dir, 0.0f);
 144         columns[1] = compose(cross(right_dir, look_dir), 0.0f);
 145         columns[2] = compose(-look_dir, 0.0f);
 146         columns[3] = compose(position, 1.0f);
 147         matrix = Matrix::from_columns(columns);
 148         view_matrix = invert(matrix);
 149
 150         shdata.uniform("world_eye_matrix", matrix);
 151         shdata.uniform("eye_world_matrix", view_matrix);
 152 }
 153
 154 void Camera::set_debug_name(const string &name)
 155 {
 156 #ifdef DEBUG
 157         shdata.set_debug_name(name+" [UBO]");
 158 #else
 159         (void)name;
 160 #endif
 161 }
 162
 163
 164 Camera::Loader::Loader(Camera &c):
 165         DataFile::ObjectLoader<Camera>(c)
 166 {
 167         add("aspect_ratio", &Loader::aspect_ratio);
 168         add("depth_clip", &Loader::depth_clip);
 169         add("field_of_view", &Loader::field_of_view);
 170         add("look_at", &Loader::look_at);
 171         add("look_direction", &Loader::look_direction);
 172         add("orthographic", &Loader::orthographic);
 173         add("position", &Loader::position);
 174         add("up_direction", &Loader::up_direction);
 175 }
 176
 177 void Camera::Loader::aspect_ratio(float a)
 178 {
 179         obj.set_aspect_ratio(a);
 180 }
 181
 182 void Camera::Loader::depth_clip(float n, float f)
 183 {
 184         obj.set_depth_clip(n, f);
 185 }
 186
 187 void Camera::Loader::field_of_view(float a)
 188 {
 189         obj.set_field_of_view(Geometry::Angle<float>::from_degrees(a));
 190 }
 191
 192 void Camera::Loader::look_at(float x, float y, float z)
 193 {
 194         obj.look_at(Vector3(x, y, z));
 195 }
 196
 197 void Camera::Loader::look_direction(float x, float y, float z)
 198 {
 199         obj.set_look_direction(Vector3(x, y, z));
 200 }
 201
 202 void Camera::Loader::orthographic(float w, float h)
 203 {
 204         obj.set_orthographic(w, h);
 205 }
 206
 207 void Camera::Loader::position(float x, float y, float z)
 208 {
 209         obj.set_position(Vector3(x, y, z));
 210 }
 211
 212 void Camera::Loader::up_direction(float x, float y, float z)
 213 {
 214         obj.set_up_direction(Vector3(x, y, z));
 215 }
 216
 217 } // namespace GL
 218 } // namespace Msp