沿顯示邊界移動2d框

目前，我可以通過顯示邊界左右移動框，但我無法弄清楚如何上下移動框。我希望盒子在顯示器周圍環繞導航，例如向右，然後向下，然後向左，然後向上，然後不斷地在整個顯示器上移動。這是我對我的實體類代碼：沿顯示邊界移動2d框

import java.awt.Rectangle; 
import org.lwjgl.opengl.GL11; 

class Entity 
{ 
private static enum State { START, LEFT, RIGHT, UP, DOWN}; 

private Rectangle box; 
private State state; 
private float speed;  // pixels/ms 

public Entity(float speed) 
{ 
    box = new Rectangle(10, 10, 10, 10); 
    state = State.START; 
    this.speed = speed; 
} 

public void draw() 
{ 
    float x = (float)box.getX(); 
    float y = (float)box.getY(); 
    float w = (float)box.getWidth(); 
    float h = (float)box.getWidth(); 


    // draw the square 

    GL11.glColor3f(0,1,0); 
    GL11.glBegin(GL11.GL_QUADS); 

    GL11.glVertex2f(x, y); 
    GL11.glVertex2f(x+w, y); 
    GL11.glVertex2f(x+w, y+w); 
    GL11.glVertex2f(x, y+w); 

    GL11.glEnd(); 

} 

public void update(int delta) 
{ 
    switch (state) 
    { 
    case START: 
     state = State.RIGHT; 


    case RIGHT: 

     box.translate((int)(speed*delta), 0); 

     if (box.getX() >= 800) 
     { 
      state = State.LEFT; 
     } 

     break; 


    case LEFT: 

     box.translate((int)(-speed*delta), 0); 

     if (box.getX() <= 0) 
     { 
      state = State.RIGHT; 
     } 

     break;    
    } 

} 
}

這裏是我的代碼GameLoop：

import org.lwjgl.Sys; 
import org.lwjgl.opengl.Display; 
import org.lwjgl.opengl.DisplayMode; 
import org.lwjgl.opengl.GL11; 

import org.lwjgl.input.Keyboard; 
import org.lwjgl.LWJGLException; 


public class GameLoop 
{ 
public static final int TARGET_FPS=100; 
public static final int SCR_WIDTH=800; 
public static final int SCR_HEIGHT=600; 

public static void main(String[] args) throws LWJGLException 
{ 
    initGL(SCR_WIDTH, SCR_HEIGHT); 

    Entity e = new Entity(.1f); 


    long time = (Sys.getTime()*4000)/Sys.getTimerResolution(); // ms 
    while (! Display.isCloseRequested()) 
    { 
     long time2 = (Sys.getTime()*4000)/ 
      Sys.getTimerResolution(); // ms 
     int delta = (int)(time2-time); 
     System.out.println(delta); 

     e.update(delta); 


     GL11.glClear(GL11.GL_COLOR_BUFFER_BIT); 

     e.draw(); 


     // UPDATE DISPLAY 
     Display.update(); 
     Display.sync(TARGET_FPS); 
     time = time2; 
    } 

    Display.destroy(); 
} 


public static void initGL(int width, int height) throws LWJGLException 
{ 
    // open window of appropriate size 
    Display.setDisplayMode(new DisplayMode(width, height)); 
    Display.create(); 
    Display.setVSyncEnabled(true); 

    // enable 2D textures 
    GL11.glEnable(GL11.GL_TEXTURE_2D);    

    // set "clear" color to black 
    GL11.glClearColor(0.0f, 0.0f, 0.0f, 0.0f);   

    // enable alpha blending 
    GL11.glEnable(GL11.GL_BLEND); 
    GL11.glBlendFunc(GL11.GL_SRC_ALPHA, GL11.GL_ONE_MINUS_SRC_ALPHA); 

    // set viewport to entire window 
    GL11.glViewport(0,0,width,height); 

    // set up orthographic projectionr 
    GL11.glMatrixMode(GL11.GL_PROJECTION); 
    GL11.glLoadIdentity(); 
    GL11.glOrtho(0, width, height, 0, 1, -1); 
    // GLU.gluPerspective(90f, 1.333f, 2f, -2f); 
    // GL11.glTranslated(0, 0, -500); 
    GL11.glMatrixMode(GL11.GL_MODELVIEW); 
} 
}

任何幫助，將不勝感激。每次改變方向時，我還需要讓盒子改變顏色。

來源

2017-08-31 Jonathan Mensi

糾正我，如果我錯了，但我認爲你只需要使用box.translate(0,value)向上或向下移動您的矩形。只要將你的左右移動調整到方框的y值即可。您也可以使用州來確定應該繪製哪種顏色。

來源

2017-09-01 11:52:38 C1bergh0st

沿顯示邊界移動2d框

回答

相關問題