caster.cpp

#include "caster.h"
#include "constants.h"
#include <cmath>

void handleEvents(sf::RenderWindow& window) {
    sf::Event event;
    while (window.pollEvent(event)) {
        if (event.type == sf::Event::Closed)
            window.close();
    }
}

double calcFrameTime(sf::Clock& clock, double& oldTime) {
    sf::Time elapsed = clock.getElapsedTime();
    double now = elapsed.asMilliseconds();
    double frameTime = (now - oldTime) / 1000.0;
    oldTime = now;
    
    return frameTime;
}
void handleMouseMovement(sf::RenderWindow& window,
    sf::Vector2<double>& playerDir,
    sf::Vector2<double>& playerPlane,
    double mouseSensitivity,sf::Vector2<int> delta){

        double msens = mouseSensitivity; 
        double rotationAmount = -delta.x * msens;
        
        double oldDirX = playerDir.x;
        playerDir.x = playerDir.x * cos(rotationAmount) - playerDir.y * sin(rotationAmount);
        playerDir.y = oldDirX * sin(rotationAmount) + playerDir.y * cos(rotationAmount);
        
        double oldPlaneX = playerPlane.x;
        playerPlane.x = playerPlane.x * cos(rotationAmount) - playerPlane.y * sin(rotationAmount);
        playerPlane.y = oldPlaneX * sin(rotationAmount) + playerPlane.y * cos(rotationAmount);

    }

void movement(const int worldMap[24][24],
    sf::Vector2<double>& playerPos,
    sf::Vector2<double>& playerDir,
    sf::Vector2<double>& playerPlane,
    double moveSpeed,
    double rotSpeed) {

if (sf::Keyboard::isKeyPressed(sf::Keyboard::W)) {
    if (worldMap[int(playerPos.x + playerDir.x * moveSpeed)][int(playerPos.y)] == 0)
  playerPos.x += playerDir.x * moveSpeed;
    if (worldMap[int(playerPos.x)][int(playerPos.y + playerDir.y * moveSpeed)] == 0)
  playerPos.y += playerDir.y * moveSpeed;
}

if (sf::Keyboard::isKeyPressed(sf::Keyboard::S)) {

if (worldMap[int(playerPos.x - playerDir.x * moveSpeed)][int(playerPos.y)] == 0)
  playerPos.x -= playerDir.x * moveSpeed;
    if (worldMap[int(playerPos.x)][int(playerPos.y - playerDir.y * moveSpeed)] == 0)
  playerPos.y -= playerDir.y * moveSpeed;
}

//if (sf::Keyboard::isKeyPressed(sf::Keyboard::D)) {
//    double oldDirX = playerDir.x;
//    playerDir.x = playerDir.x * cos(-rotSpeed) - playerDir.y * sin(-rotSpeed);
//    playerDir.y = oldDirX * sin(-rotSpeed) + playerDir.y * cos(-rotSpeed);
//
//    double oldPlaneX = playerPlane.x;
//    playerPlane.x = playerPlane.x * cos(-rotSpeed) - playerPlane.y * sin(-rotSpeed);
//    playerPlane.y = oldPlaneX * sin(-rotSpeed) + playerPlane.y * cos(-rotSpeed);
//}
//
//if (sf::Keyboard::isKeyPressed(sf::Keyboard::A)) {
//    double oldDirX = playerDir.x;
//    playerDir.x = playerDir.x * cos(rotSpeed) - playerDir.y * sin(rotSpeed);
//    playerDir.y = oldDirX * sin(rotSpeed) + playerDir.y * cos(rotSpeed);
//
//    double oldPlaneX = playerPlane.x;
//    playerPlane.x = playerPlane.x * cos(rotSpeed) - playerPlane.y * sin(rotSpeed);
//    playerPlane.y = oldPlaneX * sin(rotSpeed) + playerPlane.y * cos(rotSpeed);
//}
}
////void castFloornCeiling(sf::RenderWindow& window,
//        const int worldMap[24][24],
//        sf::Vector2<double>& playerPos,
//        sf::Vector2<double>& playerDir,
//        sf::Vector2<double>& playerPlane) {
//        
//        
//    sf::VertexArray floorCeiling(sf::Points);
//
//    for(int y = 0; y<screenHeight; y++){
//
//        sf::Vector2<float> rayDir0(playerDir.x - playerPlane.x , playerDir.y - playerPlane.y);
//        sf::Vector2<float> rayDir1(playerDir.x + playerPlane.x , playerDir.y + playerPlane.y);
//
//        int p = y-screenHeight /2;
//        if (p == 0) continue;
//
//        float zPos = 0.5 * screenHeight;
//        float rowDistance = zPos / p;
//
//        sf::Vector2<double> floorStep(rowDistance * (rayDir1.x - rayDir0.x) / screenWidth,rowDistance * (rayDir1.y - rayDir0.y) / screenWidth);
//        sf::Vector2<double> floorCords(playerPos.x+ rowDistance * rayDir0.x ,playerPos.y+rowDistance*rayDir0.y);
//        
//        for(int x = 0; x<screenWidth; x++){
//            //sf::Vector2<int> cellCord((int)(floorCords.x),(int)(floorCords.y))        
//            
//            
//            floorCeiling.append(sf::Vertex(sf::Vector2f(x, y), sf::Color::Red));
//
//            // Draw ceiling pixel (symmetrical)
//            floorCeiling.append(sf::Vertex(sf::Vector2f(x, screenHeight - y - 1),sf::Color::Red));
//
//            // Advance floor world position
//            floorCords.x += floorStep.x;
//            floorCords.y += floorStep.y;
//            
//        }
//    
//    }
//    window.draw(floorCeiling);
//
//    }

void castRays(sf::RenderWindow& window,
        const int worldMap[24][24],
        sf::Vector2<double>& playerPos,
        sf::Vector2<double>& playerDir,
        sf::Vector2<double>& playerPlane) {

    for (int x = 0; x < screenWidth; ++x) {
            double cameraX = 2.0 * x / double(screenWidth) - 1.0;
            sf::Vector2<double> rayDir(
                playerDir.x + playerPlane.x * cameraX,
                playerDir.y + playerPlane.y * cameraX
            );

            sf::Vector2<int> mapPos(int(playerPos.x), int(playerPos.y));

            sf::Vector2<double> sideDist;


            double bignum = 1e30;

            sf::Vector2<double> deltaDist(
                    (rayDir.x == 0.0) ? bignum : std::abs(1.0 / rayDir.x),
                    (rayDir.y == 0.0) ? bignum : std::abs(1.0 / rayDir.y)
                    );
            double perpWallDist = 0.0;


            sf::Vector2<int> step(0, 0);

            if(rayDir.x < 0) {
                step.x = -1;
                sideDist.x =(playerPos.x - mapPos.x) * deltaDist.x;
            } else {
                step.x = 1;
                sideDist.x =(mapPos.x + 1.0 - playerPos.x) * deltaDist.x;
            }

            if(rayDir.y < 0) {
                step.y = -1;
                sideDist.y =(playerPos.y - mapPos.y) * deltaDist.y;
            } else {
                step.y = 1;
                sideDist.y =(mapPos.y + 1.0 - playerPos.y) * deltaDist.y;
            }

            int hit = 0;
            int side = 0;
            while (hit == 0) {
                if (sideDist.x < sideDist.y) {
                    sideDist.x += deltaDist.x;
                    mapPos.x += step.x;
                    side = 0;
                } else {
                    sideDist.y += deltaDist.y;
                    mapPos.y += step.y;
                    side = 1;
                }

                if (mapPos.x < 0 || mapPos.x >= mapWidth || mapPos.y < 0 || mapPos.y >= mapHeight) {
                    hit =1;
                    break;
                }

                if (worldMap[mapPos.x][mapPos.y] > 0) hit = 1;
            }

            if (side == 0) perpWallDist = sideDist.x - deltaDist.x;
            else    perpWallDist = sideDist.y - deltaDist.y;

            int lineHeight = (perpWallDist > 0.0) ? int(screenHeight / perpWallDist) : screenHeight;

            int drawStart = -lineHeight / 2 + screenHeight / 2;
            if (drawStart < 0) drawStart = 0;
            int drawEnd = lineHeight / 2 + screenHeight / 2;
            if(drawEnd >= screenHeight) drawEnd = screenHeight - 1;

            sf::Color col = sf::Color::Yellow;
            switch (worldMap[mapPos.x][mapPos.y]) {
                case 1: col = sf::Color::Red; break;
                case 2: col = sf::Color::Green; break;
                case 3: col = sf::Color::Blue; break;
                case 4: col = sf::Color::White; break;
                case 5: col = sf::Color::Black; break;
                default: break;
            }

            if (side == 1) col = sf::Color(col.r / 2, col.g / 2, col.b/2);

            sf::RectangleShape column(sf::Vector2(1.f, float(drawEnd - drawStart +1)));
            column.setPosition(float(x), float(drawStart));
            column.setFillColor(col);
            window.draw(column);        
    }
}