OpenGL simulate Prince of persia camera - opengl

Question

I have an object "character" which can turn around itself left and right and move forward in its face direction, and a camera always looks at the object and can rotate around it.
The problem is : I want to move the camera with the object movement in its direction regardless the camera direction as in Prince of Persia, if the character face against the camera direction and the character move forward this means if the camera is not moving the character become more near to the camera so if the camera is moveable the camera should move back to make the distance between them the same, if the character looks to the right then the camera should moves to its right and so on for any direction, the camera have position, front, right and up vectors and yaw and pitch angles, the character has position and yaw and pitch angles.
the code which makes the character move is:
void Mesh::Move(Move_Directions direction, GLfloat deltaTime) {
GLfloat velocity = 50 * this->movementSpeed * deltaTime;
if (direction == FORWARD) {
glm::vec3 t = glm::vec3(sin(glm::radians(yaw)), 0.0, cos(glm::radians(yaw))) * velocity;
matrix = glm::translate(matrix, t);
for (GLuint i = 0; i < this->m_Entries.size(); i++) {
this->m_Entries[i].setModelMatrix(matrix);
}
//scene->getDefCamera()->Translate(t);
}
if (direction == BACKWARD) {
glm::vec3 t = glm::vec3(sin(glm::radians(yaw)), 0.0, cos(glm::radians(yaw))) * velocity;
matrix = glm::translate(matrix, -t);
for (GLuint i = 0; i < this->m_Entries.size(); i++) {
this->m_Entries[i].setModelMatrix(matrix);
}
//scene->getDefCamera()->Translate(t);
}
if (direction == RIGHT) {
matrix = glm::rotate(matrix, (GLfloat) -M_PI*deltaTime, glm::vec3(0.0, 1.0, 0.0));
for (GLuint i = 0; i < this->m_Entries.size(); i++) {
this->m_Entries[i].setModelMatrix(matrix);
}
}
if (direction == LEFT) {
matrix = glm::rotate(matrix, (GLfloat) M_PI*deltaTime, glm::vec3(0.0, 1.0, 0.0));
for (GLuint i = 0; i < this->m_Entries.size(); i++) {
this->m_Entries[i].setModelMatrix(matrix);
}
}
}
and the code of camera is:
void Camera::updateVectors() {
GLfloat radius = glm::length(center - position);
position.x = radius * cos(glm::radians(this->yaw)) * cos(glm::radians(this->pitch));
position.y = radius * sin(glm::radians(this->pitch));
position.z = radius * sin(glm::radians(this->yaw)) * cos(glm::radians(this->pitch));
this->front = glm::normalize(center - position);
this->right = glm::normalize(glm::cross(this->front, this->worldUp));
this->up = glm::normalize(glm::cross(this->right, this->front));
}

Answer 1

You want to add a behaviour to your camera base maybe on the distance to the object. Maybe add a treshold, if camera.pos - object.pos < d, move the camera else the camera should stay at its position.
For your image you can compute the vector your object is facing.
When you take your "z,q,s,d" input you should move the character and the camera with the same amount