LWJGL跳跃

Question

我目前正在使用LWJGL构建一个小游戏，我得到了一个包含我的游戏循环、实例等的游戏类.以及一个Player类，它包含构造函数(用于x和y弦)、计算的逻辑方法、按键等。以及在屏幕上绘制播放机的渲染方法。由于某种原因，当我按下(Key.UP)时，玩家跳下地板，然后向上跳到地板上(倒转，而不是向上跳，然后下降到地板上)。如果你能告诉我问题出在哪里，我会非常感激的。

Game.java:

import static org.lwjgl.opengl.GL11.*;

import java.io.IOException;

import org.lwjgl.LWJGLException;
import org.lwjgl.input.Keyboard;
import org.lwjgl.opengl.Display;
import org.lwjgl.opengl.DisplayMode;
import org.newdawn.slick.opengl.Texture;
import org.newdawn.slick.opengl.TextureLoader;
import org.newdawn.slick.util.ResourceLoader;


public class Game {

    static Texture bgTexture;

    static Player player;

    public static void main(String[] args) throws LWJGLException, IOException {
        // Initialize
        Display.setDisplayMode(new DisplayMode(640, 480));
        Display.create();

        glEnable(GL_TEXTURE_2D);
        glClearColor(0.0f, 0.0f, 0.0f, 0.0f);
        glEnable(GL_BLEND);
        glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
        glViewport(0, 0, 640, 480);
        glMatrixMode(GL_PROJECTION);
        glLoadIdentity();
        glOrtho(0, 640, 480, 0, 1, -1);
        glMatrixMode(GL_MODELVIEW);

        bgTexture = TextureLoader.getTexture("PNG", ResourceLoader.getResourceAsStream("res/background.png"));

        player = new Player(50, 200 - 64);

        while (!Display.isCloseRequested()) {
            glClear(GL_COLOR_BUFFER_BIT);

            drawBackground();
            player.render();

            Display.update();
            Display.sync(60);

            if (Keyboard.isKeyDown(Keyboard.KEY_ESCAPE)) {
                Display.destroy();
                System.exit(0);
            }
        }
    }

    public static void drawBackground() {
        bgTexture.bind();

        glBegin(GL_QUADS);
        glTexCoord2f(0, 0);
        glVertex2f(0, 0);
        glTexCoord2f(1, 0);
        glVertex2f(bgTexture.getTextureWidth(), 0);
        glTexCoord2f(1, 1);
        glVertex2f(bgTexture.getTextureWidth(), bgTexture.getTextureHeight());
        glTexCoord2f(0, 1);
        glVertex2f(0, bgTexture.getTextureHeight());
        glEnd();
    }

}

Player.java

import static org.lwjgl.opengl.GL11.*;

import java.io.IOException;

import org.lwjgl.input.Keyboard;
import org.newdawn.slick.opengl.Texture;
import org.newdawn.slick.opengl.TextureLoader;
import org.newdawn.slick.util.ResourceLoader;


public class Player {

    public double x, y, xspeed, yspeed;

    private Texture pTexture;

    public Player(double x, double y) throws IOException {
        this.x = x;
        this.y = y;
        pTexture = TextureLoader.getTexture("PNG", ResourceLoader.getResourceAsStream("res/player.png"));
    }

    public void logic() {
        x += xspeed;
        y += yspeed;

        yspeed -= 0.4;

        // Collision detection
        if (y <= 480 - 64) {
            y = 480 - 64;
            yspeed = 0;

            if (!Keyboard.isKeyDown(Keyboard.KEY_RIGHT) && xspeed > 0) xspeed = xspeed * 0.7;
            if (!Keyboard.isKeyDown(Keyboard.KEY_LEFT) && xspeed < 0) xspeed = xspeed * 0.7;
            if (Keyboard.isKeyDown(Keyboard.KEY_UP)) yspeed = 8;
        }

        // Moving
        if (Keyboard.isKeyDown(Keyboard.KEY_RIGHT)) xspeed = 4;
        if (Keyboard.isKeyDown(Keyboard.KEY_LEFT)) xspeed = -4;
    }

    public void render() {
        logic();

        glPushMatrix();
        pTexture.bind();
        glTranslated(x, y, 0);

        glBegin(GL_QUADS);
        glTexCoord2d(0, 0);
        glVertex2d(0, 0);
        glTexCoord2d(1, 0);
        glVertex2d(pTexture.getTextureWidth(), 0);
        glTexCoord2d(1, 1);
        glVertex2d(pTexture.getTextureWidth(), pTexture.getTextureHeight());
        glTexCoord2d(0, 1);
        glVertex2d(0, pTexture.getTextureHeight());
        glEnd();

        glPopMatrix();
    }

}

非常感谢。

Answer 1

您正在调用glOrtho(0, 640, 480, 0, 1, -1);，它将480设置为屏幕底部，0设置为顶部。如果您使用glOrtho(0, 640, 0, 480, 1, -1);，一个较大的y值将意味着屏幕上的一个更高的点，这就是我想要的。