// This function handles the collision between the ball and a wall
void World::wall_collide_handler(const CollisionEntry& colEntry)
{
// First we calculate some numbers we need to do a reflection
NodePath renderNp = m_windowFrameworkPtr->get_render();
// The normal of the wall
LVector3f norm = colEntry.get_surface_normal(renderNp) * -1;
// The current speed
float curSpeed = m_ballV.length();
// The direction of travel
LVector3f inVec = m_ballV / curSpeed;
// Angle of incidence
float velAngle = norm.dot(inVec);
LPoint3f hitDir = colEntry.get_surface_point(renderNp) - m_ballRootNp.get_pos();
hitDir.normalize();
// The angle between the ball and the normal
float hitAngle = norm.dot(hitDir);
// Ignore the collision if the ball is either moving away from the wall
// already (so that we don't accidentally send it back into the wall)
// and ignore it if the collision isn't dead-on (to avoid getting caught on
// corners)
if(velAngle > 0 && hitAngle > .995)
{
// Standard reflection equation
LVector3f reflectVec = (norm * norm.dot(inVec * -1) * 2) + inVec;
// This makes the velocity half of what it was if the hit was dead-on
// and nearly exactly what it was if this is a glancing blow
m_ballV = reflectVec * (curSpeed * (((1-velAngle)*.5)+.5));
// Since we have a collision, the ball is already a little bit buried in
// the wall. This calculates a vector needed to move it so that it is
// exactly touching the wall
LPoint3f disp = (colEntry.get_surface_point(renderNp) -
colEntry.get_interior_point(renderNp));
LPoint3f newPos = m_ballRootNp.get_pos() + disp;
m_ballRootNp.set_pos(newPos);
}
}
// Accepts arrow keys to move either the player or the menu cursor,
// Also deals with grid checking and collision detection
void World::move()
{
// If the camera-left key is pressed, move camera left.
// If the camera-right key is pressed, move camera right.
NodePath cameraNp = m_windowFrameworkPtr->get_camera_group();
cameraNp.look_at(m_ralph);
if(m_keyMap[K_cam_left] != false)
{
cameraNp.set_x(cameraNp, -20 * ClockObject::get_global_clock()->get_dt());
}
if(m_keyMap[K_cam_right] != false)
{
cameraNp.set_x(cameraNp, +20 * ClockObject::get_global_clock()->get_dt());
}
// save ralph's initial position so that we can restore it,
// in case he falls off the map or runs into something.
LPoint3f startPos = m_ralph.get_pos();
// If a move-key is pressed, move ralph in the specified direction.
if(m_keyMap[K_left])
{
m_ralph.set_h(m_ralph.get_h() + 300 * ClockObject::get_global_clock()->get_dt());
}
if(m_keyMap[K_right])
{
m_ralph.set_h(m_ralph.get_h() - 300 * ClockObject::get_global_clock()->get_dt());
}
if(m_keyMap[K_forward])
{
m_ralph.set_y(m_ralph, -25 * ClockObject::get_global_clock()->get_dt());
}
// If ralph is moving, loop the run animation.
// If he is standing still, stop the animation.
if(m_keyMap[K_forward] || m_keyMap[K_left] || m_keyMap[K_right])
{
if(!m_isMoving)
{
m_ralph.loop("run", true);
m_isMoving = true;
}
}
else
{
if(m_isMoving)
{
m_ralph.stop("run");
m_ralph.pose("walk", 5);
m_isMoving = false;
}
}
// If the camera is too far from ralph, move it closer.
// If the camera is too close to ralph, move it farther.
LPoint3f camVec = m_ralph.get_pos() - cameraNp.get_pos();
camVec.set_z(0);
float camDist = camVec.length();
camVec.normalize();
if(camDist > 10.0)
{
cameraNp.set_pos(cameraNp.get_pos() + camVec*(camDist-10));
camDist = 10.0;
}
if(camDist < 5.0)
{
cameraNp.set_pos(cameraNp.get_pos() - camVec*(5-camDist));
camDist = 5.0;
}
// Now check for collisions.
NodePath renderNp = m_windowFrameworkPtr->get_render();
m_collisionTraverser.traverse(renderNp);
// Adjust ralph's Z coordinate. If ralph's ray hit terrain,
// update his Z. If it hit anything else, or didn't hit anything, put
// him back where he was last frame.
m_ralphGroundHandlerPtr->sort_entries();
if(m_ralphGroundHandlerPtr->get_num_entries() > 0 &&
m_ralphGroundHandlerPtr->get_entry(0)->get_into_node()->get_name() == "terrain")
{
m_ralph.set_z(m_ralphGroundHandlerPtr->get_entry(0)->get_surface_point(renderNp).get_z());
}
else
{
m_ralph.set_pos(startPos);
}
// Keep the camera at one foot above the terrain,
// or two feet above ralph, whichever is greater.
m_camGroundHandlerPtr->sort_entries();
if(m_camGroundHandlerPtr->get_num_entries() > 0 &&
m_camGroundHandlerPtr->get_entry(0)->get_into_node()->get_name() == "terrain")
{
cameraNp.set_z(m_camGroundHandlerPtr->get_entry(0)->get_surface_point(renderNp).get_z()+1.0);
}
if(cameraNp.get_z() < m_ralph.get_z() + 2.0)
{
cameraNp.set_z(m_ralph.get_z() + 2.0);
}
// The camera should look in ralph's direction,
// but it should also try to stay horizontal, so look at
// a floater which hovers above ralph's head.
m_floaterNp.set_pos(m_ralph.get_pos());
m_floaterNp.set_z(m_ralph.get_z() + 2.0);
cameraNp.look_at(m_floaterNp);
}
