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C-/C++-Quelltext

void Camera::calculateViewMatrix(){
    bb::vec3 rot = (m_lookAt-m_position).cross(m_up);
    rot.normalize();

    m_viewMatrix.setIdentity();
    m_viewMatrix.lookAt(m_position, m_lookAt, m_up);
    m_viewMatrix.rotate(m_rotation.y, rot); // Rotation über die "Rechtsachse"
    m_viewMatrix.rotate(m_rotation.x, 0, 0, 1);
}

C-/C++-Quelltext

Camera::ray Camera::getRay(float x, float y){ // Berechnung des rays
    float w = float(m_viewport[2]-m_viewport[0]);
    float h = float(m_viewport[3]-m_viewport[1]);

    vec3 view = (m_lookAt-m_position).normalize();
    vec3 u = vec3Cross(view, m_up).normalize();
    vec3 v = vec3Cross(u, view).normalize();

    float vLength = tan(m_fov*PI/180.0f/2.0f)*m_zNear;

    v *= vLength;
    u *= vLength*(w/h);

    x -= w/2.0f;
    x /= w/2.0f;
    y -= h/2.0f;
    y /= h/2.0f;

    ray r;
    r.position = m_position+view*m_zNear+u*x+v*y;
    r.direction = (r.position-m_position).normalize();

    return r;
}

a = r.direction.dot(r.direction); // picking in einer system klasse, hier nur der relevante Ausschnitt
b = 2*r.direction.dot(r.position);
c = r.position.dot(r.position)-object3d->m_radius*object3d->m_radius;
disc = b*b-4*a*c; // discriminant

if(disc > 0.0f){
    dist = sqrt(disc);

    if(b < 0.0f){
        q = (-b-dist)/2.0f;
    }
    else{
        q = (-b+dist)/2.0f;
    }

    t0 = q/a;
    t1 = c/q;

    if(t0 > t1){
        tmp = t0;
        t0 = t1;
        t1 = tmp;
    }

    if(t1 > 0.0f){ // erfolgreich
        std::cout<<r.position.x<<"|"<<r.position.y<<"|"<<r.position.z<<"|"<<r.direction.x<<"|"<<r.direction.y<<"|"<<r.direction.z<<std::endl;
    }

C-/C++-Quelltext

Camera::ray Camera::getRay(float x, float y){
    ray r;

    calculateViewMatrix();
    calculateProjectionMatrix();

    mat4 pv = (m_projectionMatrix*m_viewMatrix).inverse();
    float w = x/(float(m_viewport[2]-m_viewport[0])/2.0f)-1.0f;
    float h = -(y/(float(m_viewport[3]-m_viewport[1])/2.0f)-1.0f);

    vec4 n = pv*vec4(w, h, -1.0f, 1.0f);
    n /= n.w;
    vec4 f = pv*vec4(w, h, 1.0f, 1.0f);
    f /= f.w;

    r.position = vec3(n);
    r.direction = vec3(f).normalize();

    return r;
}

Quellcode

-10.8186|-10.5365|0.289706|-0.71762|-0.696084|0.0221132

C-/C++-Quelltext

vec4 mat4::operator*(const vec4 &v){
    vec4 r = vec3();

    r.x = values[0]*v.x+values[4]*v.y+values[8]*v.z+v.w*values[12];
    r.y = values[1]*v.x+values[5]*v.y+values[9]*v.z+v.w*values[13];
    r.z = values[2]*v.x+values[6]*v.y+values[10]*v.z+v.w*values[14];
    r.w = values[3]*v.x+values[7]*v.y+values[11]*v.z+v.w*values[15];

    return r;
}