grafika_komputerowa/grk/project/Bullet.h

#include "glm.hpp"
#include "src/Shader_Loader.h"
#include <vector>
#include "GameEntity.h"

#pragma once
class Bullet
{
private:
	float speed;
	float lifetime;
	glm::vec3 directionNormalized;
	glm::vec3 startPosition;
	float birthTime;
	float scale;
	//GLuint program;
	Core::RenderContext renderContext;

	float getAge(float time) {
		return time - birthTime;
	}

	Bullet(float speed, float lifetime, glm::vec3 directionNormalized, glm::vec3 startPosition, float birthTime, Core::RenderContext renderContext, float scale){
		this->speed = speed;
		this->lifetime = lifetime;
		this->directionNormalized = directionNormalized;
		this->startPosition = startPosition;
		this->birthTime = birthTime;
		this->renderContext = renderContext;
		this->scale = scale;
	}

public:
	static Bullet* createSimpleBullet(glm::vec3 directionNormalized, glm::vec3 startPosition, float birthTime) {
		static bool simpleRenderContextLoaded;
		static Core::RenderContext simpleRenderContext;
		if (!simpleRenderContextLoaded) {
			simpleRenderContextLoaded = true;
			Core::loadModelToContext("./models/sphere.obj", simpleRenderContext);
		}
		return new Bullet(10, 10, directionNormalized, startPosition, birthTime, simpleRenderContext, 0.01f);
	}

	bool shouldBeDestroyed(float time, GLuint program, std::vector<GameEntity*>& gameEntities, float attackerDmg) {
		float age = getAge(time);
		if (age > lifetime) {
			return true;
		}
		glm::mat4 modelMatrix = glm::translate(glm::mat4(1.0f), startPosition) * glm::translate(directionNormalized * speed * age) * glm::scale(glm::vec3(scale));
		Core::drawObjectPBR(renderContext, modelMatrix, glm::vec3(1.f, 0.f, 0.f), 0.3, 0, program);
		//std::cout << "x: " << modelMatrix[3].x << std::endl;
		//std::cout << "y: " << modelMatrix[3].y << std::endl;
		//std::cout << "z: " << modelMatrix[3].z << std::endl;
		if (checkCollisionWithGameEntities(gameEntities, modelMatrix, attackerDmg)) {
			return true;
		}


		return false;
	}
	bool checkCollisionWithGameEntities(std::vector<GameEntity*>& gameEntities, glm::mat4 bulletModelMatrix, float attackerDmg) {
		for (const auto& entity : gameEntities) {
			glm::mat4 entityModelMatrix = entity->getModelMatrix(); 

			if (checkAABBCollision(bulletModelMatrix, entityModelMatrix)) {
				entity->applyDamage(attackerDmg); 
				return true;
			}
		}

		return false;
	}
	bool checkAABBCollision(const glm::mat4& obj1ModelMatrix, const glm::mat4& obj2ModelMatrix) {
	
		glm::vec3 obj1Min = glm::vec3(obj1ModelMatrix * glm::vec4(-0.5f, -0.5f, -0.5f, 1.0f));
		glm::vec3 obj1Max = glm::vec3(obj1ModelMatrix * glm::vec4(0.5f, 0.5f, 0.5f, 1.0f));

		glm::vec3 obj2Min = glm::vec3(obj2ModelMatrix * glm::vec4(-0.5f, -0.5f, -0.5f, 1.0f));
		glm::vec3 obj2Max = glm::vec3(obj2ModelMatrix * glm::vec4(0.5f, 0.5f, 0.5f, 1.0f));

		// Sprawd<77> kolizj<7A> wzd<7A>u<EFBFBD> trzech osi (x, y, z)
		bool collisionX = obj1Max.x >= obj2Min.x && obj1Min.x <= obj2Max.x;
		bool collisionY = obj1Max.y >= obj2Min.y && obj1Min.y <= obj2Max.y;
		bool collisionZ = obj1Max.z >= obj2Min.z && obj1Min.z <= obj2Max.z;

		// Kolizja wyst<73>puje tylko wtedy, gdy zachodzi kolizja na wszystkich trzech osiach
		return collisionX && collisionY && collisionZ;
	}

};