spieleprogrammierer.de - Forum und Wiki zur Spieleprogrammierung und Spieleentwicklung

C-/C++-Quelltext

// file: Player.cpp
// project: Pong
// created by: Typ
// 
//
#include "Texture.h"
#include "Game.hpp"
#include "Ball.hpp"

#include <iostream>
#include <SDL2\SDL.h>
#include <string>
#include <math.h>

#define pi 3.14

// Init
void CBall::Init(SDL_Renderer* renderer, std::string file)
{
    // save filename
    this->file = file;

    // startposition 
    xPos = 1024 / 2;    
    yPos = 512 / 2;

    // initialize ball
    ball = new Texture(renderer, file);
    ball->Draw(xPos, yPos);

    // startdirection to the right
    direction = 20.0f;

    // set the speed
    speed = 0.15f;
}

// Update
void CBall::Update(SDL_Renderer* renderer, int player1X, int player1Y, int player2X, int player2Y)
{
    // check, if ball hits a paddle
    if (checkPaddleCollision(player1X, player1Y, player2X, player2Y))
    {
        if (direction < 90.0f && direction > 0.0f)              // direction in the 1. quadrant
            direction = direction + (180.0f - 2.0f * direction);
        else if (direction < 180.0f && direction > 90.0f)       // direction in the 2. quadrant
            direction = direction - (2.0f * (direction - 90.0f));
        else if (direction < 270.0f && direction > 180.0f)      // direction in the 3. quadrant
            direction = direction + (180.0f - 2.0f * direction);
        else                                                    // direction in the 4. quadrant
            direction = direction - (2.0f * (direction - 90.0f));
    }

    // check, if ball hits the wall
    if (checkWallCollision())
    {
        if (direction < 90.0f && direction > 0.0f)              // direction in the 1. quadrant
            direction = 360.0f - (2.0f * direction);
        else if (direction < 180.0f && direction > 90.0f)       // direction in the 2. quadrant
            direction = 180.0f + 2.0f * (180.0f - direction);
        else if (direction < 270.0f && direction > 180.0f)      // direction in the 3. quadrant
            direction = 180.0f - 2.0f * (direction - 180.0f);
        else                                                    // direction in the 4. quadrant
            direction = 360.0f + 2.0f * (360.0f - direction);
    }

    // calculate new position
    xPos += (getXPos() * speed);
    yPos += (getYPos() * speed);

    // draw new position
    ball->Draw(xPos, yPos);
}

float CBall::getXPos()
{
    float radians = direction / 180 * pi;           // calculate radians
    return cos(radians);
}

float CBall::getYPos()
{
    float radians = direction / 180 * pi;           // calculate radians
    return -sin(radians);
}

bool CBall::checkPaddleCollision(int player1X, int player1Y, int player2X, int player2Y)
{
    // collision with paddle
    if (yPos > player1Y && yPos < player1Y + 30 && xPos < player1X)                 // left paddle
        return true;
    else if (yPos > player2Y && yPos < player2Y + 30 && xPos > player2X)            // right paddle
        return true;

    
    return false;
}

bool CBall::checkWallCollision()
{
    // collision with wall
    if (yPos + 10 > 512 || yPos < 0)
        return true;

    return false;
}