// Integrate forces into positions using RK4 step
int LinearBody::RK4Step()
{
// Recalculate all forces
double realTimestep = timestep;
timestep /= 2;
UpdateForces();
// Check if dead
if (DeathCheck())
return 1;
// Apply RK4 Step using new forces
for (ALLNODES_i) {
}
return 0;
}
// Integrate forces into positions using a simple euler step.
// You should really keep the timestep <0.01 for this type of integration.
int LinearBody::EulerStep()
{
// Recalculate all forces
UpdateForces();
// Check if we're dead. Return with error if already dead.
if (DeathCheck())
return 1;
// Apply simple euler step using new forces
for (ALLNODES_i) {
// update velocity a = F / m
nodes[i].v.x += (nodes[i].a.x)*timestep;
nodes[i].v.y += (nodes[i].a.y)*timestep;
// update posiiton
nodes[i].p.x += (nodes[i].v.x)*timestep;
nodes[i].p.y += (nodes[i].v.y)*timestep;
}
return 0;
}
/*
This function handles gaining / losing HP.
It handles various different scenarios, and should be able to handle every possible one.
*/
bool CMobs::ChangeHP(unsigned long ByWhat, bool Decrease, bool ThisIsChecked)
{
// Handle if we have a negative number.
if ( Decrease )
{
// If we have enough HP left to take away.
if (HP >= ByWhat)
{
HP -= ByWhat;
}
// Else if we don't, just set the HP to 0.
else if (HP < ByWhat)
{
// If this is not a check of some sort, kill the player (Like if this is monster damage).
if (!ThisIsChecked)
{
HP = 0;
}
// If this is a check, just return false so we know the player doesn't have enough
// HP to perform the operation they are trying to do (like use a skill).
else if (ThisIsChecked)
{
return false;
}
}
// This would mean the monster has died recently.
if (Dead == false && HP == 0)
{
Player.ChangeEXP(EXPGiven, false);
CItems *NewItem = new CItems(9001, 10, this->GetRect());
Items.push_back( NewItem );
}
// If the player has 0 HP, they are dead. Set this value accordingly.
if (HP == 0)
{
Dead = true;
}
}
// Handle if we have a positive number.
else if ( !Decrease )
{
// If we are trying to gain more hp than the max.
if ( (HP + ByWhat) > MaxHP )
{
// Just heal to full.
HP = MaxHP;
}
// Otherwise, we're just trying a regular heal, so just increase HP normally.
else
{
HP += ByWhat;
}
// If the player has the dead flag set, we just healed HP meaning they can't have 0 anymore. Set this value accordingly.
// This function might be called with a value of 0 for whatever reason, and since in this case we don't want a major exploit where
// you could be alive with 0 HP, we will always check if they are dead AND have greater than 0 hp before setting them to alive.
if (Dead == true && HP > 0)
{
Dead = false;
}
}
DeathCheck();
return true;
}
