java - LWJGL - 帮助移动纹理立方体

Question

package com.idonedid.game;

import org.lwjgl.LWJGLException;
import org.lwjgl.opengl.Display;
import org.lwjgl.opengl.DisplayMode;
import org.lwjgl.opengl.GL11;
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 Prime {
    private boolean done = false;
    private boolean fullscreen = false;
    private final String windowTitle = "NeHe's OpenGL Lesson 6 for LWJGL (Texture Mapping)";
    private boolean f1 = false;
    private DisplayMode displayMode;

    private float xrot;            // X Rotation ( NEW )
    private float yrot;            // Y Rotation ( NEW )
    private float zrot;            // Z Rotation ( NEW )
    private Texture texture;           // Storage For One Texture ( NEW )
    private float zPos;
    public static void main(String args[]) {
    boolean fullscreen = false;
    if(args.length>0) {
        if(args[0].equalsIgnoreCase("fullscreen")) {
            fullscreen = true;
        }
    }

    Prime app = new Prime();
    app.run(fullscreen);
}
public void run(boolean fullscreen) {
    this.fullscreen = fullscreen;
    try {
        init();
        while (!done) {
            mainloop();
            render();
            Display.update();
        }
        cleanup();
    }
    catch (Exception e) {
        e.printStackTrace();
        System.exit(0);
    }
}
private void mainloop() throws LWJGLException {
    if(Keyboard.isKeyDown(Keyboard.KEY_ESCAPE)) {       // Exit if Escape is pressed
        done = true;
    }
    if(Display.isCloseRequested()) {                     // Exit if window is closed
        done = true;
    }
    if(Keyboard.isKeyDown(Keyboard.KEY_W))
    {
        zPos += 0.1f;
    }
    if (!Keyboard.isKeyDown(Keyboard.KEY_W))
    {
        zPos = 0f;
    }
}

private void switchMode() {
    fullscreen = !fullscreen;
    try {
        Display.setFullscreen(fullscreen);
    }
    catch(Exception e) {
        e.printStackTrace();
    }
}

private boolean render() {
    GL11.glClear(GL11.GL_COLOR_BUFFER_BIT | GL11.GL_DEPTH_BUFFER_BIT); // Clear The Screen And The Depth Buffer

    GL11.glLoadIdentity(); // Reset The Current Modelview Matrix
    texture.bind();
    GL11.glTranslatef(0.0f, 0.0f, zPos); // Move Into The Screen 5 Units
    GL11.glRotatef(xrot, 1.0f, 0.0f, 0.0f); // Rotate On The X Axis
    GL11.glRotatef(yrot, 0.0f, 1.0f, 0.0f); // Rotate On The Y Axis
    GL11.glRotatef(zrot, 0.0f, 0.0f, 1.0f); // Rotate On The Z Axis // Select Our Texture
    GL11.glBegin(GL11.GL_QUADS);
    // Front Face
    GL11.glTexCoord2f(0.0f, 0.0f);
    GL11.glVertex3f(-1.0f, -1.0f, 1.0f); // Bottom Left Of The Texture and Quad
    GL11.glTexCoord2f(1.0f, 0.0f);
    GL11.glVertex3f(1.0f, -1.0f, 1.0f); // Bottom Right Of The Texture and Quad
    GL11.glTexCoord2f(1.0f, 1.0f);
    GL11.glVertex3f(1.0f, 1.0f, 1.0f); // Top Right Of The Texture and Quad
    GL11.glTexCoord2f(0.0f, 1.0f);
    GL11.glVertex3f(-1.0f, 1.0f, 1.0f); // Top Left Of The Texture and Quad
    // Back Face
    GL11.glTexCoord2f(1.0f, 0.0f);
    GL11.glVertex3f(-1.0f, -1.0f, -1.0f); // Bottom Right Of The Texture and Quad
    GL11.glTexCoord2f(1.0f, 1.0f);
    GL11.glVertex3f(-1.0f, 1.0f, -1.0f); // Top Right Of The Texture and Quad
    GL11.glTexCoord2f(0.0f, 1.0f);
    GL11.glVertex3f(1.0f, 1.0f, -1.0f); // Top Left Of The Texture and Quad
    GL11.glTexCoord2f(0.0f, 0.0f);
    GL11.glVertex3f(1.0f, -1.0f, -1.0f); // Bottom Left Of The Texture and Quad
    // Top Face
    GL11.glTexCoord2f(0.0f, 1.0f);
    GL11.glVertex3f(-1.0f, 1.0f, -1.0f); // Top Left Of The Texture and Quad
    GL11.glTexCoord2f(0.0f, 0.0f);
    GL11.glVertex3f(-1.0f, 1.0f, 1.0f); // Bottom Left Of The Texture and Quad
    GL11.glTexCoord2f(1.0f, 0.0f);
    GL11.glVertex3f(1.0f, 1.0f, 1.0f); // Bottom Right Of The Texture and Quad
    GL11.glTexCoord2f(1.0f, 1.0f);
    GL11.glVertex3f(1.0f, 1.0f, -1.0f); // Top Right Of The Texture and Quad
    // Bottom Face
    GL11.glTexCoord2f(1.0f, 1.0f);
    GL11.glVertex3f(-1.0f, -1.0f, -1.0f); // Top Right Of The Texture and Quad
    GL11.glTexCoord2f(0.0f, 1.0f);
    GL11.glVertex3f(1.0f, -1.0f, -1.0f); // Top Left Of The Texture and Quad
    GL11.glTexCoord2f(0.0f, 0.0f);
    GL11.glVertex3f(1.0f, -1.0f, 1.0f); // Bottom Left Of The Texture and Quad
    GL11.glTexCoord2f(1.0f, 0.0f);
    GL11.glVertex3f(-1.0f, -1.0f, 1.0f); // Bottom Right Of The Texture and Quad
    // Right face
    GL11.glTexCoord2f(1.0f, 0.0f);
    GL11.glVertex3f(1.0f, -1.0f, -1.0f); // Bottom Right Of The Texture and Quad
    GL11.glTexCoord2f(1.0f, 1.0f);
    GL11.glVertex3f(1.0f, 1.0f, -1.0f); // Top Right Of The Texture and Quad
    GL11.glTexCoord2f(0.0f, 1.0f);
    GL11.glVertex3f(1.0f, 1.0f, 1.0f); // Top Left Of The Texture and Quad
    GL11.glTexCoord2f(0.0f, 0.0f);
    GL11.glVertex3f(1.0f, -1.0f, 1.0f); // Bottom Left Of The Texture and Quad
    // Left Face
    GL11.glTexCoord2f(0.0f, 0.0f);
    GL11.glVertex3f(-1.0f, -1.0f, -1.0f); // Bottom Left Of The Texture and Quad
    GL11.glTexCoord2f(1.0f, 0.0f);
    GL11.glVertex3f(-1.0f, -1.0f, 1.0f); // Bottom Right Of The Texture and Quad
    GL11.glTexCoord2f(1.0f, 1.0f);
    GL11.glVertex3f(-1.0f, 1.0f, 1.0f); // Top Right Of The Texture and Quad
    GL11.glTexCoord2f(0.0f, 1.0f);
    GL11.glVertex3f(-1.0f, 1.0f, -1.0f); // Top Left Of The Texture and Quad
    GL11.glEnd();

    //xrot += 0.3f; // X Axis Rotation
    //yrot += 0.2f; // Y Axis Rotation
    //zrot += 0.4f; // Z Axis Rotation

    return true;
}
private void createWindow() throws Exception {
    Display.setFullscreen(fullscreen);
    Display.setDisplayMode(new DisplayMode(800, 600));
    Display.setTitle(windowTitle);
    Display.create();
}

private void init() throws Exception {
    createWindow();

    loadTextures();
    initGL();
}

private void loadTextures() throws Exception {
    texture = loadTexture("dirt.png");
}

private void initGL() {
    GL11.glEnable(GL11.GL_TEXTURE_2D); // Enable Texture Mapping
    GL11.glShadeModel(GL11.GL_SMOOTH); // Enable Smooth Shading
    GL11.glClearColor(0.0f, 0.0f, 0.0f, 0.0f); // Black Background
    GL11.glClearDepth(1.0f); // Depth Buffer Setup
    GL11.glEnable(GL11.GL_DEPTH_TEST); // Enables Depth Testing
    GL11.glDepthFunc(GL11.GL_LEQUAL); // The Type Of Depth Testing To Do

    GL11.glMatrixMode(GL11.GL_PROJECTION); // Select The Projection Matrix
    GL11.glLoadIdentity(); // Reset The Projection Matrix

    // Calculate The Aspect Ratio Of The Window
    GL11.glMatrixMode(GL11.GL_MODELVIEW); // Select The Modelview Matrix

    // Really Nice Perspective Calculations
    GL11.glHint(GL11.GL_PERSPECTIVE_CORRECTION_HINT, GL11.GL_NICEST);
}
private void cleanup() {
    Display.destroy();
}
/**
 * Texture loading using DevIL
 * Example created by Mark Bernard
 */
private Texture loadTexture(String path) throws Exception
{
    return TextureLoader.getTexture("PNG", ResourceLoader.getResourceAsStream(path));
}
}

因此，本质上，当立方体处于默认位置时，它看起来完全符合其应有的样子。如果我将 Z 位置更改为 1f 或 0f 以外的任何位置，它就会变得不可见。请帮助我理解并解决这个问题。

Answer 1

初始化 OpenGL 时，您需要添加几行:

GL11.glLoadIdentity();
GLU.gluPerspective(45.0f, window.getWidth() / window.getHeight(), 0.1f, 100.0f);
GL11.glMatrixMode(GL11.GL_MODELVIEW);
GL11.glLoadIdentity();

最后两个参数是最小和最大视距，因此它不会停在 1 处，最多可以看到 100 个单位的距离。

如果您收到有关没有 GLU 的错误，请确保您的构建路径中有 lwjgl_util.jar。