TFBot AI logic for using the BASE Jumper item

tfbot_parachute_logic.cpp

// Based on ServerLinux 20170616a

// 
// SUMMARY: when TFBots have the BASE Jumper equipped, they will press their jump button in the following manner:
// 
// If their parachute is not yet deployed, they will start holding down the jump button to deploy it if:
// - their health is at least 50%
// - AND they are not on fire
// - AND they are moving downward
// - AND they are at least 300 HU above the ground
// 
// If their parachute is currently deployed, they will continue holding down the jump button until:
// - their health falls below 50%
// - OR they catch on fire
// - OR they reach a height of less than 150 HU above the ground
// 

CTFBotUseItem *CTFBot::OpportunisticallyUseWeaponAbilities()
{
	// ...
	
	// CTFPlayerShared+0x0340: bool m_bShieldEquipped
	// CTFPlayerShared+0x0341: bool m_bParachuteEquipped
	
	if (this->IsPlayerClass(TF_CLASS_DEMOMAN) && this->m_Shared.m_bShieldEquipped) {
		
		// ...
		
	} else if (this->m_Shared.m_bParachuteEquipped) {
		bool burning = this->m_Shared.InCond(TF_COND_BURNING);
		float health_ratio = ((float)this->GetHealth() / (float)this->GetMaxHealth());
		
		auto l_is_above_ground = [](CTFBot *actor, float min_height){
			Vector from = actor->GetAbsOrigin();
			Vector to   = actor->GetAbsOrigin() - Vector(0.0f, 0.0f, min_height);
			
			return !actor->GetLocomotionInterface()->IsPotentiallyTraversable(from, to, ILocomotion::TRAVERSE_DEFAULT);
		};
		
		if (this->m_Shared.InCond(TF_COND_PARACHUTE_DEPLOYED)) {
			if (health_ratio >= 0.5f && !burning && !l_is_above_ground(this, 150.0f)) {
				this->PressJumpButton();
			} else {
				// implicit: release jump button
			}
		} else {
			if (health_ratio >= 0.5f && !burning && this->GetAbsVelocity().z < 0.0f && !l_is_above_ground(this, 300.0f)) {
				this->PressJumpButton();
			} else {
				// implicit: release jump button
			}
		}
	}
	
	// ...
}