Question

我想知道是否有人可以帮我一些代码。下面我有一些可控圆圈的代码（代表一个蛇头）

我可以修改/添加到下面的代码中，以便当蛇与边界/边界碰撞时，它会从相反的一侧重复出现？

我已将游戏分辨率设置为1024 x 768

非常感谢任何帮助：）

snake.cpp

#include "snake.hpp"

#include <cstdlib>

void Snake::move()
{
    switch(direction_){
    case Direction::North:
        position_.y += 10;
        break;
    case Direction::East:
        position_.x += 10;
        break;
    case Direction::South:
        position_.y -= 10;
        break;
    case Direction::West:
        position_.x -= 10;
    }

}


void Snake::render(prg::Canvas& canvas) const
{
    canvas.drawCircle(getPosition().x, getPosition().y,20,prg::Colour::WHITE);
}

void Snake::changeDirection(Direction new_direction)
{
    direction_ = new_direction;
}

play_state.cpp

#include "play_state.hpp"
#include "ai_snake.hpp"
#include "player_snake.hpp"
#include <iostream>

const size_t MaxShapes {5};
const unsigned int MaxScale {5};

bool PlayState::onCreate()
{
    snakes_.push_back(new AISnake);
    snakes_.back()->setPosition(Position(100,100));
    snakes_.push_back(new PlayerSnake);
    snakes_.back()->setPosition(Position(50,50));

    double x, y;
    for(unsigned shape = 0;shape < MaxShapes;shape++)
    {
        x = (double)(rand() % prg::application.getScreenWidth());
        y = (double)(rand() % prg::application.getScreenHeight());

        shapes_.push_back(Square({x, y}));

    }
    return true;
}

bool PlayState::onDestroy()
{
    return true;
}

void PlayState::onEntry()
{
    prg::application.addKeyListener(*this);
    game_timer_.start();
}

void PlayState::onExit()
{
    prg::application.removeKeyListener(*this);
    game_timer_.stop();
}

void PlayState::onUpdate()
{

}

void PlayState::onRender(prg::Canvas& canvas)
{
    const std::string text = "";

    canvas.blitFast(
        background_,
        canvas.getWidth() / 2 - background_.getWidth() / 2,
        canvas.getHeight() / 2 - background_.getHeight() / 2
    );

    prg::uint text_dims[2];
    prg::Font::MASSIVE.computePrintDimensions(text_dims, text);
    prg::Font::MASSIVE.print(
      canvas,
      prg::application.getScreenWidth() / 2 - text_dims[0] / 2,
      prg::application.getScreenHeight() / 2 - text_dims[1] / 2,
      prg::Colour::RED,
      text);

    for(const auto snake : snakes_) {
    snake->render(canvas);
    }

    for(Shape shapes : shapes_) {
    shapes.render(canvas);
    }
}

bool PlayState::onKey(const prg::IKeyEvent::KeyEvent& key_event)
{
    if(key_event.key_state == KeyEvent::KB_DOWN) {
        switch(key_event.key) {
        case KeyEvent::KB_ESC_KEY:
            prg::application.exit();
            break;

        }
    }
    return true;
}

void PlayState::onTimer(prg::Timer& timer)
{
    for(auto snake : snakes_) {
        snake->move();
    }
}

play_state.hpp

#if !defined PLAY_STATE_HPP
#define PLAY_STATE_HPP

#include <prg_interactive.hpp>
#include "snake.hpp"
#include "square.hpp"
#include <list>


//Example of forward declaration of Snake class
class Snake;

class PlayState final : public prg::IAppState,
                        public prg::IKeyEvent,
                        public prg::ITimerEvent {
public:
    PlayState() = default;
    bool onCreate() override;
    bool onDestroy() override;
    void onEntry() override;
    void onExit() override;
    void onUpdate() override;
    void onRender(prg::Canvas& canvas) override;

    bool onKey(const prg::IKeyEvent::KeyEvent& key_event) override;
    void onTimer(prg::Timer& timer) override;

private:
    //Snake* snakes_[2] {nullptr,nullptr};
    std::list<Snake*> snakes_;
    prg::Timer game_timer_ {0, 1000 / 30, *this};
    const prg::Image background_ {prg::ImageFile("resources/images/border.bmp").load()};

        std::vector<Shape> shapes_;
};

#endif // PLAY_STATE_HPP

Answer 1

这适用于 1024x768 的边界：

if (position_.x < 0) position_.x = 1023; else if (position_.x > 1023) position_.x = 0;
if (position_.y < 0) position_.y = 767; else if (position_.y > 767) position_.y = 0;

请注意，宽度 1024 表示 X 介于 0 和 1023 之间！

从您的代码判断，您使用10x10的块。如果是这种情况，您应该根据需要自定义上面的代码。

修改

从评论和我的回答中，我将此合并到您可以遵循的代码中：

#include "snake.hpp" #include <cstdlib> void Snake::move() { switch(direction_){ case Direction::North: position_.y += 1; break; case Direction::East: position_.x += 1; break; case Direction::South: position_.y -= 1; break; case Direction::West: position_.x -= 1; } if (position_.x < 0) position_.x = 63; else if (position_.x > 63) position_.x = 0; if (position_.y < 0) position_.y = 47; else if (position_.y > 47) position_.y = 0; } void Snake::render(prg::Canvas& canvas) const { canvas.drawCircle(getPosition().x * 16, getPosition().y * 16,16,prg::Colour::WHITE); } void Snake::changeDirection(Direction new_direction) { direction_ = new_direction; }

这是一个16x16像素的64x48网格，分辨率为1024x768。

玩得开心！

蛇游戏边境碰撞

1 个答案: