void Alien::Update(float deltaTime)
{
if (!DoneMoving)
{
Position = Owner.Transform.Position.ToVec2();
Steering = PathFollowing();
Truncate(Steering, MAX_FORCE);
Steering *= 1 / Mass;
Velocity += Steering;
Truncate(Velocity, MAX_VELOCITY);
Owner.Transform.Position += vec3(Velocity.x, Velocity.y, 0);
}
}
/*
* Move Entity by MoveX, MoveY pixels
* The move is done in tiny increments determined by the speed factor
* rather than in one large move to MoveX, MoveY
*/
void CEntity::Move(float MoveX, float MoveY)
{
if (MoveX == 0 && MoveY == 0) return; // We've stopped
CanJump = false; // We don't yet know if we can jump
float speedfactor = CFramerate::FPSControl.GetSpeedFactor();
MoveX *= speedfactor;
MoveY *= speedfactor;
//Store the step increment in each direction
double NewX = 0;
double NewY = 0;
if (MoveX != 0) NewX = (MoveX >= 0) ? speedfactor : -speedfactor; // for going left or right
if (MoveY != 0) NewY = (MoveY >= 0) ? speedfactor : -speedfactor; // for going up or down
while(true)
{
if(Flags & ENTITY_FLAG_GHOST) // Can pass through everything
{
PositionValid((int)(X + NewX), (int)(Y + NewY)); //We don't care about collisions, but we need to send events to other entities
X += NewX;
Y += NewY;
}
else // Check for Collisions in X & Y direction
{
if (OnSlope())
{
if ( PositionValid((int)(X + NewX), (int)(Y)), true )
X += NewX;
else
SpeedX = 0;
if ( PositionValid( (int)(X), (int)(Y + NewY)), true )
Y += NewY + Slope_Offset_Y;
CanJump = true;
SpeedY = 0;
}else
{
// Can we move in X
if ( PositionValid((int)(X + NewX), (int)(Y)) )
{
X += NewX;
if (Carrying)
Carrying->X += NewX;
}else
SpeedX = 0;
// Can we move in Y
if ( PositionValid( (int)(X), (int)(Y + NewY)) )
{
Y += NewY;
// It's a platform (or similar) with something on it
if (Carrying && (MoveUp || MoveDown))
Carrying->Y = Y - Carrying->Height;
}
else // We are on the floor
{
CanJump = true;
SpeedY = 0;
}
}
}
// Check Path Following
PathFollowing();
// Reduce MoveX, MoveY by the step increment
MoveX += -NewX;
MoveY += -NewY;
// Check for over-run
if(NewX > 0 && MoveX <= 0) NewX = 0;
if(NewX < 0 && MoveX >= 0) NewX = 0;
if(NewY > 0 && MoveY <= 0) NewY = 0;
if(NewY < 0 && MoveY >= 0) NewY = 0;
if(MoveX == 0) NewX = 0;
if(MoveY == 0) NewY = 0;
// Check if we're finished
if(MoveX == 0 && MoveY == 0) break;
if(NewX == 0 && NewY == 0) break;
}
}