Use libmspmath to provide vector and matrix operations

[libs/gl.git] / source / camera.cpp

diff --git a/source/camera.cpp b/source/camera.cpp
index 98b7598ca16ffa011d1849881ac0d67117bff45f..406135796f3e10c1cc0135cb23a097ee51e32259 100644 (file)
--- a/source/camera.cpp
+++ b/source/camera.cpp
@@ -39,29 +39,21 @@ void Camera::set_position(const Vector3 &p)
 
 void Camera::set_up_direction(const Vector3 &u)
 {
-       float len = sqrt(u.x*u.x+u.y*u.y+u.z*u.z);
-
-       up_dir.x = u.x/len;
-       up_dir.y = u.y/len;
-       up_dir.z = u.z/len;
+       up_dir = normalize(u);
 
        compute_matrix();
 }
 
 void Camera::set_look_direction(const Vector3 &l)
 {
-       float len = sqrt(l.x*l.x+l.y*l.y+l.z*l.z);
-
-       look_dir.x = l.x/len;
-       look_dir.y = l.y/len;
-       look_dir.z = l.z/len;
+       look_dir = normalize(l);
 
        compute_matrix();
 }
 
 void Camera::look_at(const Vector3 &p)
 {
-       set_look_direction(Vector3(p.x-position.x, p.y-position.y, p.z-position.z));
+       set_look_direction(p-position);
 }
 
 Vector3 Camera::project(const Vector4 &p) const
@@ -70,12 +62,15 @@ Vector3 Camera::project(const Vector4 &p) const
        float frustum_w = frustum_h*aspect;
        float z_range = clip_far-clip_near;
 
-       float eye_x = matrix[0]*p.x+matrix[4]*p.y+matrix[8]*p.z+matrix[12]*p.w;
-       float eye_y = matrix[1]*p.x+matrix[5]*p.y+matrix[9]*p.z+matrix[13]*p.w;
-       float eye_z = matrix[2]*p.x+matrix[6]*p.y+matrix[10]*p.z+matrix[14]*p.w;
+       Vector4 eye = matrix*p;
 
-       return Vector3(eye_x/frustum_w/-eye_z, eye_y/frustum_h/-eye_z,
-               (clip_far+clip_near)/z_range+2*clip_far*clip_near/(eye_z*z_range));
+       return Vector3(eye.x/frustum_w/-eye.z, eye.y/frustum_h/-eye.z,
+               (clip_far+clip_near)/z_range+2*clip_far*clip_near/(eye.z*z_range));
+}
+
+Vector3 Camera::project(const Vector3 &p) const
+{
+       return project(Vector4(p.x, p.y, p.z, 1.0));
 }
 
 Vector4 Camera::unproject(const Vector4 &p) const
@@ -102,19 +97,16 @@ void Camera::apply() const
 
 void Camera::compute_matrix()
 {
-       float x = look_dir.y*up_dir.z-look_dir.z*up_dir.y;
-       float y = look_dir.z*up_dir.x-look_dir.x*up_dir.z;
-       float z = look_dir.x*up_dir.y-look_dir.y*up_dir.x;
-       float len = sqrt(x*x+y*y+z*z);
+       Vector3 right_dir = normalize(cross(look_dir, up_dir));
        double mdata[16];
 
-       mdata[0] = x/len;
-       mdata[4] = y/len;
-       mdata[8] = z/len;
+       mdata[0] = right_dir.x;
+       mdata[4] = right_dir.y;
+       mdata[8] = right_dir.z;
 
-       mdata[1] = mdata[4]*look_dir.z-mdata[8]*look_dir.y;
-       mdata[5] = mdata[8]*look_dir.x-mdata[0]*look_dir.z;
-       mdata[9] = mdata[0]*look_dir.y-mdata[4]*look_dir.x;
+       mdata[1] = right_dir.y*look_dir.z-right_dir.z*look_dir.y;
+       mdata[5] = right_dir.z*look_dir.x-right_dir.x*look_dir.z;
+       mdata[9] = right_dir.x*look_dir.y-right_dir.y*look_dir.x;
 
        mdata[2] = -look_dir.x;
        mdata[6] = -look_dir.y;