//!!!WARNING: Code in this method should not depend on how many times this method is run
void Player::updateState() {
//states
if (mHpLossTimer.exceededReset()) {
hurt(mInCloud);
}
//Apply impulse
cpVect totalVel = cpvadd(mVel,mVectp);
if (cpvlength(totalVel) != 0) {
cpBodyApplyImpulseAtWorldPoint(mEntity->body(), totalVel, cpv(0, 0));
mVel = cpvzero;
mVectp = cpvzero;
}
mVectp = cpvzero;
cpBody * body = mEntity->body();
for(int i=0; i<mMaxAmmo; i++)
if( mAmmo[i].checkExist() )
mAmmo[i].move();
//Move around screen
if( body->p.x > SCREEN_WIDTH + mEntity->width()/2 )
body->p.x = -mEntity->width();
if( body->p.x < -mEntity->width() )
body->p.x = SCREEN_WIDTH + mEntity->width()/2;
if( body->p.y > SCREEN_HEIGHT + mEntity->height()/2)
body->p.y = -mEntity->height();
if( body->p.y < -mEntity->height() )
body->p.y = SCREEN_HEIGHT + mEntity->height()/2;
}
ETERM *body_apply_impulse(ETERM *fromp, ETERM *argp) {
// get the args
ETERM *space_refp = erl_element(1, argp);
ETERM *idp = erl_element(2, argp);
ETERM *impulsep = erl_element(3, argp);
erlmunk_space *s;
int space_id = ERL_REF_NUMBER(space_refp);
HASH_FIND_INT(erlmunk_spaces, &space_id, s);
int body_id = ERL_INT_VALUE(idp);
erlmunk_body *b;
HASH_FIND_INT(s->bodies, &body_id, b);
if (b == NULL)
return NULL;
// apply the impulse at the center of the body and along it's current angle
float angle = deg_to_rad(cpBodyGetAngle(b->body));
cpVect angleV = cpvforangle(angle);
cpVect impulse = cpvmult(angleV, ERL_FLOAT_VALUE(impulsep));
cpBodyApplyImpulseAtWorldPoint(b->body, impulse, angleV);
return NULL;
}
void RCPBody::applyImpulse(RVector const & impulse)
{
if (mBody) {
cpBodyApplyImpulseAtWorldPoint(mBody, cpv(impulse.x(), impulse.y()), cpBodyLocalToWorld(mBody, cpBodyGetCenterOfGravity(mBody)));
}
}
void RigidBody2D::AddImpulse(const Vector2f& impulse, const Vector2f& point, CoordSys coordSys)
{
switch (coordSys)
{
case CoordSys_Global:
cpBodyApplyImpulseAtWorldPoint(m_handle, cpv(impulse.x, impulse.y), cpv(point.x, point.y));
break;
case CoordSys_Local:
cpBodyApplyImpulseAtLocalPoint(m_handle, cpv(impulse.x, impulse.y), cpv(point.x, point.y));
break;
}
}
cpBool Buoyancy::WaterPreSolve(cpArbiter *arb, cpSpace *space, void *ptr)
{
CP_ARBITER_GET_SHAPES(arb, water, poly);
cpBody *body = cpShapeGetBody(poly);
// Get the top of the water sensor bounding box to use as the water level.
cpFloat level = cpShapeGetBB(water).t;
// Clip the polygon against the water level
int count = cpPolyShapeGetCount(poly);
int clippedCount = 0;
#ifdef _MSC_VER
// MSVC is pretty much the only compiler in existence that doesn't support variable sized arrays.
cpVect clipped[10];
#else
cpVect clipped[count + 1];
#endif
for(int i=0, j=count-1; i<count; j=i, i++){
cpVect a = cpBodyLocalToWorld(body, cpPolyShapeGetVert(poly, j));
cpVect b = cpBodyLocalToWorld(body, cpPolyShapeGetVert(poly, i));
if(a.y < level){
clipped[clippedCount] = a;
clippedCount++;
}
cpFloat a_level = a.y - level;
cpFloat b_level = b.y - level;
if(a_level*b_level < 0.0f){
cpFloat t = cpfabs(a_level)/(cpfabs(a_level) + cpfabs(b_level));
clipped[clippedCount] = cpvlerp(a, b, t);
clippedCount++;
}
}
// Calculate buoyancy from the clipped polygon area
cpFloat clippedArea = cpAreaForPoly(clippedCount, clipped, 0.0f);
cpFloat displacedMass = clippedArea*FLUID_DENSITY;
cpVect centroid = cpCentroidForPoly(clippedCount, clipped);
cpDataPointer data = ptr;
DrawPolygon(clippedCount, clipped, 0.0f, RGBAColor(0, 0, 1, 1), RGBAColor(0, 0, 1, 0.1f), data);
DrawDot(5, centroid, RGBAColor(0, 0, 1, 1), data);
cpFloat dt = cpSpaceGetCurrentTimeStep(space);
cpVect g = cpSpaceGetGravity(space);
// Apply the buoyancy force as an impulse.
cpBodyApplyImpulseAtWorldPoint(body, cpvmult(g, -displacedMass*dt), centroid);
// Apply linear damping for the fluid drag.
cpVect v_centroid = cpBodyGetVelocityAtWorldPoint(body, centroid);
cpFloat k = k_scalar_body(body, centroid, cpvnormalize(v_centroid));
cpFloat damping = clippedArea*FLUID_DRAG*FLUID_DENSITY;
cpFloat v_coef = cpfexp(-damping*dt*k); // linear drag
// cpFloat v_coef = 1.0/(1.0 + damping*dt*cpvlength(v_centroid)*k); // quadratic drag
cpBodyApplyImpulseAtWorldPoint(body, cpvmult(cpvsub(cpvmult(v_centroid, v_coef), v_centroid), 1.0/k), centroid);
// Apply angular damping for the fluid drag.
cpVect cog = cpBodyLocalToWorld(body, cpBodyGetCenterOfGravity(body));
cpFloat w_damping = cpMomentForPoly(FLUID_DRAG*FLUID_DENSITY*clippedArea, clippedCount, clipped, cpvneg(cog), 0.0f);
cpBodySetAngularVelocity(body, cpBodyGetAngularVelocity(body)*cpfexp(-w_damping*dt/cpBodyGetMoment(body)));
return cpTrue;
}
