stk-code_catmod/src/spark.cpp
hikerstk bf4ee7a970 1) Bugfix: rescuing kart (at least) in the startrack would
trigger a rescue loop: rescue, drop, rescue, drop, ...
2) Some code cleanup.


git-svn-id: svn+ssh://svn.code.sf.net/p/supertuxkart/code/trunk/supertuxkart@1394 178a84e3-b1eb-0310-8ba1-8eac791a3b58
2008-01-15 11:38:54 +00:00

96 lines
3.7 KiB
C++

// $Id: spark.cpp 1284 2007-11-08 12:31:54Z hikerstk $
//
// SuperTuxKart - a fun racing game with go-kart
// Copyright (C) 2007 Joerg Henrichs
//
// This program is free software; you can redistribute it and/or
// modify it under the terms of the GNU General Public License
// as published by the Free Software Foundation; either version 2
// of the License, or (at your option) any later version.
//
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU General Public License for more details.
//
// You should have received a copy of the GNU General Public License
// along with this program; if not, write to the Free Software
// Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
#include "spark.hpp"
float Spark::m_st_max_distance; // maximum distance for a spark to be attracted
float Spark::m_st_force_to_target;
// -----------------------------------------------------------------------------
Spark::Spark(Kart *kart) : Flyable(kart, COLLECT_SPARK)
{
float y_offset = -0.5f*kart->getKartLength()-2.0f*m_extend.getY();
float speed = -m_speed;
// if the kart is driving backwards, release from the front
if(m_owner->getSpeed()<0)
{
y_offset = -y_offset;
speed = -speed;
}
createPhysics(y_offset, btVector3(0.0f, speed, 0.0f),
new btSphereShape(0.5f*m_extend.getY()));
// unset no_contact_response flags, so that the spark
// will bounce off the track
int flag = getBody()->getCollisionFlags();
flag = flag & (~ btCollisionObject::CF_NO_CONTACT_RESPONSE);
getBody()->setCollisionFlags(flag);
} // Spark
// -----------------------------------------------------------------------------
void Spark::init(const lisp::Lisp* lisp, ssgEntity *spark)
{
Flyable::init(lisp, spark, COLLECT_SPARK);
m_st_max_distance = 20.0f;
m_st_force_to_target = 10.0f;
lisp->get("max-distance", m_st_max_distance );
lisp->get("force-to-target", m_st_force_to_target);
} // init
// -----------------------------------------------------------------------------
void Spark::update(float dt)
{
Flyable::update(dt);
const Kart *kart=0;
btVector3 direction;
float minDistance;
getClosestKart(&kart, &minDistance, &direction);
if(minDistance<m_st_max_distance) // move spark towards kart
{
direction*=1/direction.length()*m_st_force_to_target;
m_body->applyCentralForce(direction);
}
else
{ // Sparks lose energy (e.g. when hitting the track), so increase the
// speed if the spark is too slow, but only if it's not too high (if
// the spark is too high, it is 'pushed down', which can reduce the
// speed, which causes the speed to increase, which in turn causes
// the spark to fly higher and higher.
btVector3 v=m_body->getLinearVelocity();
btTransform trans=getTrans();
float hat = trans.getOrigin().getZ();
if (hat<= m_max_height)
{
float vlen = v.length2();
if(vlen<0.8*m_speed*m_speed)
{ // spark lost energy (less than 80%), i.e. it's too slow - speed it up:
if(vlen==0.0f) {
v = btVector3(.5f, .5f, .5f); // avoid 0 div.
}
else
{
m_body->setLinearVelocity(v*m_speed/sqrt(vlen));
}
} // vlen < 0.8*m_speed*m_speed
} // hat< m_max_height
} // spar lose energy
} // update
// -----------------------------------------------------------------------------