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POJava openGL draw texture
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copied!<p>I try to draw a basic texture in LWJGL, but I can't.</p> <p>My main class: </p> <pre><code>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++; } } </code></pre> <p>And my texture loader:</p> <pre><code>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; } } </code></pre> <p>It's not an actual game, just a test to learn and practice openGL in java. Also anyone can suggest me a good book on OpenGL?</p>

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