我尝试在 LWJGL 中绘制基本纹理，但我不能。
我的主课:
package worldofportals;
import java.io.IOException;
import java.util.logging.FileHandler;
import java.util.logging.Level;
import java.util.logging.Logger;
import org.lwjgl.LWJGLException;
import org.lwjgl.Sys;
import org.lwjgl.input.Keyboard;
import org.lwjgl.input.Mouse;
import org.lwjgl.opengl.Display;
import org.lwjgl.opengl.DisplayMode;
import org.lwjgl.opengl.GL11;
import static org.lwjgl.opengl.GL11.*;
import static org.lwjgl.util.glu.GLU.*;
import worldofportals.texture.TextureLoader;
/**
* Initialize the program, handle the rendering, updating, the mouse and the
* keyboard events.
*
* @author Laxika
*/
public class WorldOfPortals {
/**
* Time at the last frame.
*/
private long lastFrame;
/**
* Frames per second.
*/
private int fps;
/**
* Last FPS time.
*/
private long lastFPS;
public static final int DISPLAY_HEIGHT = 1024;
public static final int DISPLAY_WIDTH = 768;
public static final Logger LOGGER = Logger.getLogger(WorldOfPortals.class.getName());
int tileId = 0;
static {
try {
LOGGER.addHandler(new FileHandler("errors.log", true));
} catch (IOException ex) {
LOGGER.log(Level.WARNING, ex.toString(), ex);
}
}
public static void main(String[] args) {
WorldOfPortals main = null;
try {
main = new WorldOfPortals();
main.create();
main.run();
} catch (Exception ex) {
LOGGER.log(Level.SEVERE, ex.toString(), ex);
} finally {
if (main != null) {
main.destroy();
}
}
}
/**
* Create a new lwjgl frame.
*
* @throws LWJGLException
*/
public void create() throws LWJGLException {
//Display
Display.setDisplayMode(new DisplayMode(DISPLAY_WIDTH, DISPLAY_HEIGHT));
Display.setFullscreen(false);
Display.setTitle("World of Portals FPS: 0");
Display.create();
//Keyboard
Keyboard.create();
//Mouse
Mouse.setGrabbed(false);
Mouse.create();
//OpenGL
initGL();
resizeGL();
getDelta(); // call once before loop to initialise lastFrame
lastFPS = getTime();
glEnable(GL_TEXTURE_2D); //Enable texturing
tileId = TextureLoader.getInstance().loadTexture("img/tile1.png");
}
/**
* Destroy the game.
*/
public void destroy() {
//Methods already check if created before destroying.
Mouse.destroy();
Keyboard.destroy();
Display.destroy();
}
/**
* Initialize the GL.
*/
public void initGL() {
//2D Initialization
glClearColor(0.0f, 0.0f, 0.0f, 0.0f);
glDisable(GL_DEPTH_TEST);
glDisable(GL_LIGHTING);
}
/**
* Handle the keyboard events.
*/
public void processKeyboard() {
}
/**
* Handle the mouse events.
*/
public void processMouse() {
}
/**
* Handle the rendering.
*/
public void render() {
glPushMatrix();
glClear(GL_COLOR_BUFFER_BIT);
for (int i = 0; i < 30; i++) {
for (int j = 30; j >= 0; j--) { // Changed loop condition here.
glBindTexture(GL_TEXTURE_2D, tileId);
// translate to the right location and prepare to draw
GL11.glTranslatef(20, 20, 0);
GL11.glColor3f(0, 0, 0);
// draw a quad textured to match the sprite
GL11.glBegin(GL11.GL_QUADS);
{
GL11.glTexCoord2f(0, 0);
GL11.glVertex2f(0, 0);
GL11.glTexCoord2f(0, 64);
GL11.glVertex2f(0, DISPLAY_HEIGHT);
GL11.glTexCoord2f(64, 64);
GL11.glVertex2f(DISPLAY_WIDTH, DISPLAY_HEIGHT);
GL11.glTexCoord2f(64, 0);
GL11.glVertex2f(DISPLAY_WIDTH, 0);
}
GL11.glEnd();
}
}
// restore the model view matrix to prevent contamination
GL11.glPopMatrix();
}
/**
* Resize the GL.
*/
public void resizeGL() {
//2D Scene
glViewport(0, 0, DISPLAY_WIDTH, DISPLAY_HEIGHT);
glMatrixMode(GL_PROJECTION);
glLoadIdentity();
gluOrtho2D(0.0f, DISPLAY_WIDTH, 0.0f, DISPLAY_HEIGHT);
glPushMatrix();
glMatrixMode(GL_MODELVIEW);
glLoadIdentity();
glPushMatrix();
}
public void run() {
while (!Display.isCloseRequested() && !Keyboard.isKeyDown(Keyboard.KEY_ESCAPE)) {
if (Display.isVisible()) {
processKeyboard();
processMouse();
update(getDelta());
render();
} else {
if (Display.isDirty()) {
render();
}
}
Display.update();
Display.sync(60);
}
}
/**
* Game update before render.
*/
public void update(int delta) {
updateFPS();
}
/**
* Get the time in milliseconds
*
* @return The system time in milliseconds
*/
public long getTime() {
return (Sys.getTime() * 1000) / Sys.getTimerResolution();
}
/**
* Calculate how many milliseconds have passed since last frame.
*
* @return milliseconds passed since last frame
*/
public int getDelta() {
long time = getTime();
int delta = (int) (time - lastFrame);
lastFrame = time;
return delta;
}
/**
* Calculate the FPS and set it in the title bar
*/
public void updateFPS() {
if (getTime() - lastFPS > 1000) {
Display.setTitle("World of Portals FPS: " + fps);
fps = 0;
lastFPS += 1000;
}
fps++;
}
}
还有我的纹理加载器:
package worldofportals.texture;
import java.awt.image.BufferedImage;
import java.io.File;
import java.io.IOException;
import java.nio.ByteBuffer;
import javax.imageio.ImageIO;
import org.lwjgl.BufferUtils;
import static org.lwjgl.opengl.GL11.*;
import org.lwjgl.opengl.GL12;
public class TextureLoader {
private static final int BYTES_PER_PIXEL = 4;//3 for RGB, 4 for RGBA
private static TextureLoader instance;
private TextureLoader() {
}
public static TextureLoader getInstance() {
if (instance == null) {
instance = new TextureLoader();
}
return instance;
}
/**
* Load a texture from file.
*
* @param loc the location of the file
* @return the id of the texture
*/
public int loadTexture(String loc) {
BufferedImage image = loadImage(loc);
int[] pixels = new int[image.getWidth() * image.getHeight()];
image.getRGB(0, 0, image.getWidth(), image.getHeight(), pixels, 0, image.getWidth());
ByteBuffer buffer = BufferUtils.createByteBuffer(image.getWidth() * image.getHeight() * BYTES_PER_PIXEL); //4 for RGBA, 3 for RGB
for (int y = 0; y < image.getHeight(); y++) {
for (int x = 0; x < image.getWidth(); x++) {
int pixel = pixels[y * image.getWidth() + x];
buffer.put((byte) ((pixel >> 16) & 0xFF)); // Red component
buffer.put((byte) ((pixel >> 8) & 0xFF)); // Green component
buffer.put((byte) (pixel & 0xFF)); // Blue component
buffer.put((byte) ((pixel >> 24) & 0xFF)); // Alpha component. Only for RGBA
}
}
buffer.flip();
int textureID = glGenTextures(); //Generate texture ID
glBindTexture(GL_TEXTURE_2D, textureID); //Bind texture ID
//Setup wrap mode
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL12.GL_CLAMP_TO_EDGE);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL12.GL_CLAMP_TO_EDGE);
//Setup texture scaling filtering
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
//Send texel data to OpenGL
glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA8, image.getWidth(), image.getHeight(), 0, GL_RGBA, GL_UNSIGNED_BYTE, buffer);
//Return the texture ID so we can bind it later again
return textureID;
}
/**
* Load an image from disc.
*
* @param loc the location of the image
* @return the image
*/
private BufferedImage loadImage(String loc) {
try {
return ImageIO.read(new File(loc));
} catch (IOException e) {
e.printStackTrace();
}
return null;
}
}
这不是一个真正的游戏，只是一个在java中学习和练习openGL的测试。还有人可以推荐一本关于 OpenGL 的好书吗？
最佳答案
你尝试过吗:
BufferedImage image = loadImage(loc);
image.getRGB(0, 0, image.getWidth(), image.getHeight(), pixels, 0, image.getWidth());
ByteBuffer buffer = BufferUtils.createByteBuffer(image.getWidth() * image.getHeight() * 4);
Color c;
for (int y = 0; y < image.getHeight(); y++) {
for (int x = 0; x < image.getWidth(); x++) {
c = new Color(image.getRGB(x, y));
buffer.put((byte) c.getRed()); // Red component
buffer.put((byte) c.getGreen()); // Green component
buffer.put((byte) c.getBlue()); // Blue component
buffer.put((byte) c.getAlpha()); // Alpha component. Only for RGBA
}
}
此外，如果要放置 Alpha 组件，则应该检查组件的数量，只有在有 4 个组件时才添加 Alpha，或者始终使用 4 个组件。此外，请使用 GL_RGBA 而不是 GL_RGBA8。
关于Java openGL绘制纹理，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/11584444/