纹理lwjgl / opengl高度图?

时间:2013-09-20 23:29:32

标签: opengl textures lwjgl heightmap

如何为高度贴图添加纹理?我按照TheCodingUniverse的教程#36(我认为是数字)来创建高度贴图,他使用着色器来设置X高度的X颜色,但是我想为X高度设置XX纹理而不是每个高度的颜色。我该怎么做呢?

我尝试绑定纹理,因为我正在绘制三角形条(就像我在GL_QUADS的3D方格上所做的那样),但是高度图无法渲染。然而,世界上所有其他事物仍在继续呈现。

StackOverflow抱怨我的信息太少,但除了代码示例之外,我不确定除了代码样本还有什么要告诉你的。

当前高度图代码:

package Terrain;

import org.lwjgl.BufferUtils;
import org.lwjgl.LWJGLException;
import org.lwjgl.input.Keyboard;
import org.lwjgl.input.Mouse;
import org.lwjgl.opengl.Display;
import org.lwjgl.opengl.DisplayMode;
import org.lwjgl.opengl.GL20;
import org.lwjgl.util.glu.GLU;
import org.lwjgl.util.glu.Sphere;

import com.bulletphysics.collision.broadphase.BroadphaseInterface;
import com.bulletphysics.collision.broadphase.DbvtBroadphase;
import com.bulletphysics.collision.dispatch.CollisionConfiguration;
import com.bulletphysics.collision.dispatch.CollisionDispatcher;
import com.bulletphysics.collision.dispatch.CollisionObject;
import com.bulletphysics.collision.dispatch.DefaultCollisionConfiguration;
import com.bulletphysics.collision.shapes.CollisionShape;
import com.bulletphysics.collision.shapes.SphereShape;
import com.bulletphysics.collision.shapes.StaticPlaneShape;
import com.bulletphysics.dynamics.DiscreteDynamicsWorld;
import com.bulletphysics.dynamics.RigidBody;
import com.bulletphysics.dynamics.RigidBodyConstructionInfo;
import com.bulletphysics.dynamics.constraintsolver.ConstraintSolver;
import com.bulletphysics.dynamics.constraintsolver.SequentialImpulseConstraintSolver;
import com.bulletphysics.linearmath.DefaultMotionState;
import com.bulletphysics.linearmath.MotionState;
import com.bulletphysics.linearmath.Transform;

import utility.EulerCamera;
import utility.ShaderLoader;

import javax.imageio.ImageIO;
import javax.vecmath.Matrix4f;
import javax.vecmath.Quat4f;
import javax.vecmath.Vector3f;

import java.awt.*;
import java.awt.image.BufferedImage;
import java.io.File;
import java.io.FileInputStream;
import java.io.IOException;
import java.nio.ByteBuffer;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.HashSet;
import java.util.Set;

import static org.lwjgl.opengl.GL11.*;
import static org.lwjgl.opengl.GL13.*;
import static org.lwjgl.opengl.GL20.*;

/**
 * A 3D terrain loaded from a height-map and a lookup texture. Press 'L' to reload the shader and texture files. Press
 * 'P' to switch between normal, point, and wire-frame mode. Press 'F' to flatten the terrain. Click here for an image:
 * https://twitter.com/i/#!/CodingUniverse/media/slideshow?url=pic.twitter.com%2FDgMdZ5jm.
 *
 * @author Oskar Veerhoek
 */
public class TexturedTerrain {



    private static final String WINDOW_TITLE = "Terrain!";
    private static final int[] WINDOW_DIMENSIONS = {1200, 650};
    // private static final EulerCamera camera = new EulerCamera.Builder().setPosition(-5.4f, 19.2f,
        //    33.2f).setRotation(30, 61, 0).setAspectRatio(ASPECT_RATIO).setFieldOfView(60).build();
    private static EulerCamera camera = new EulerCamera.Builder()
    .setFieldOfView(60)
    .setNearClippingPane(0.3f)
    .setFarClippingPane(500)
    .setPosition(0, 25, 15)
    .build();
    /**
     * The shader program that will use the lookup texture and the height-map's vertex data to draw the terrain.
     */
    public static int shaderProgram;
    /**
     * The texture that will be used to find out which colours correspond to which heights.
     */
    public static int lookupTexture;
    public static int textureTerrain;
    /**
     * The display list that will contain the height-map's vertex data.
     */
        public static int heightmapDisplayList;
    /**
     * The points of the height. The first dimension represents the z-coordinate. The second dimension represents the
     * x-coordinate. The float value represents the height.
     */
    public static float[][] data;
    /**
     * Whether the terrain should vary in height or be displayed on a grid.
     */
    private static boolean flatten = false;

    public static void render() {
        // Clear the pixels on the screen and clear the contents of the depth buffer (3D contents of the scene)
        glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
        // Reset any translations the camera made last frame update
        glLoadIdentity();
        // Apply the camera position and orientation to the scene
        camera.applyTranslations();
        if (flatten) {
            glScalef(1, 0, 1);
        }
        // Render the heightmap using the shaders that are being used
        glCallList(heightmapDisplayList);
    }

    private static void input() {
        while (Keyboard.next()) {
            if (Keyboard.getEventKeyState()) {
                if (Keyboard.isKeyDown(Keyboard.KEY_F)) {
                    flatten = !flatten;
                }
                if (Keyboard.getEventKey() == Keyboard.KEY_ESCAPE){
                        Display.destroy();     
                        System.exit(0);
                }
                if (Keyboard.getEventKey() == Keyboard.KEY_L) {
                    // Reload the shaders and the heightmap data.
                    glUseProgram(0);
                    glDeleteProgram(shaderProgram);
                    glActiveTexture(GL_TEXTURE0);
                    glBindTexture(GL_TEXTURE_2D, 0);
                    glActiveTexture(GL_TEXTURE1);
                    glBindTexture(GL_TEXTURE_2D, 0);
                    glDeleteTextures(lookupTexture);
                    glDeleteTextures(textureTerrain);
                    setUpShaders();
                    setUpHeightmap();
                }
                if (Keyboard.getEventKey() == Keyboard.KEY_P) {
                    // Switch between normal mode, point mode, and wire-frame mode.
                    int polygonMode = glGetInteger(GL_POLYGON_MODE);
                    if (polygonMode == GL_LINE) {
                        glPolygonMode(GL_FRONT, GL_FILL);
                    } else if (polygonMode == GL_FILL) {
                        glPolygonMode(GL_FRONT, GL_POINT);
                    } else if (polygonMode == GL_POINT) {
                        glPolygonMode(GL_FRONT, GL_LINE);
                    }
                }
            }
        }
        if (Mouse.isButtonDown(0)) {
            Mouse.setGrabbed(true);
        } else if (Mouse.isButtonDown(1)) {
            Mouse.setGrabbed(false);
        }
        if (Mouse.isGrabbed()) {
            camera.processMouse(1, 80, -80);
        }
        camera.processKeyboard(16, 1);
    }

    private static int loadTexture(String path) throws IOException {
        // Create an input stream for the 'lookup texture', a texture that will used by the fragment shader to
        // determine which colour matches which height on the heightmap
        FileInputStream inputStream = new FileInputStream(path);
        // Create a class that will give us information about the image file (width and height) and give us the
        // texture data in an OpenGL-friendly manner
        PNGDecoder decoder = new PNGDecoder(inputStream);
        // Create a ByteBuffer in which to store the contents of the texture. Its size is the width multiplied by
        // the height and 4, which stands for the amount of bytes a float is in Java.
        ByteBuffer buffer = BufferUtils.createByteBuffer(4 * decoder.getWidth() * decoder.getHeight());
        // 'Decode' the texture and store its data in the buffer we just created
        decoder.decode(buffer, decoder.getWidth() * 4, PNGDecoder.Format.RGBA);
        // Make the contents of the ByteBuffer readable to OpenGL (and unreadable to us)
        buffer.flip();
        // Close the input stream for the heightmap 'lookup texture'
        inputStream.close();
        // Generate a texture handle for the 'lookup texture'
        int texture = glGenTextures();
        glBindTexture(GL_TEXTURE_2D, texture);
        // Hand the texture data to OpenGL
        glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, decoder.getWidth(), decoder.getHeight(), 0, GL_RGBA,
                GL_UNSIGNED_BYTE, buffer);
        glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
        glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
        //glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
        //glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
        glBindTexture(GL_TEXTURE_2D, 0);
        return texture;
    }

    public static BufferedImage image(){
        BufferedImage heightmapImage = null;
        try{
        heightmapImage = ImageIO.read(new File("res/heightmap.bmp"));
        }catch (IOException e){
                e.printStackTrace();
        }
        if (heightmapImage == null){
                return null;
        }
        return heightmapImage;
    }

    public static void setUpHeightmap() {
        try {
            // Load the heightmap-image from its resource file
            BufferedImage heightmapImage = ImageIO.read(new File("res/heightmap.bmp"));
            // Initialise the data array, which holds the heights of the heightmap-vertices, with the correct dimensions
            data = new float[heightmapImage.getWidth()][heightmapImage.getHeight()];
            // Lazily initialise the convenience class for extracting the separate red, green, blue, or alpha channels
            // an int in the default RGB color model and default sRGB colourspace.
            Color colour;
            // Iterate over the pixels in the image on the x-axis
            for (int z = 0; z < data.length; z++) {
                // Iterate over the pixels in the image on the y-axis
                for (int x = 0; x < data[z].length; x++) {
                    // Retrieve the colour at the current x-location and y-location in the image
                    colour = new Color(heightmapImage.getRGB(z, x));
                    // Store the value of the red channel as the height of a heightmap-vertex in 'data'. The choice for
                    // the red channel is arbitrary, since the heightmap-image itself only has white, gray, and black.
                    int y = colour.getRed();;
                    data[z][x] = y;
                    //xheight.put(x, y);
                    //zheight.put(z, y);
                }
            }
            lookupTexture = loadTexture("res/heightmap_lookup.png");
            //textureTerrain = loadTexture("res/heightmap.png");
        } catch (IOException e) {
            e.printStackTrace();
        }
        glBindTexture(GL_TEXTURE_2D, lookupTexture);
        // Generate a display list handle for the display list that will store the heightmap vertex data
        heightmapDisplayList = glGenLists(1);
        // TODO: Add alternative VBO rendering for pseudo-compatibility with version 3 and higher.
        glNewList(heightmapDisplayList, GL_COMPILE);
        // Scale back the display list so that its proportions are acceptable.
          //glScalef(0.4f, 0.4f, 0.4f);
        // Iterate over the 'strips' of heightmap data.

        for (int z = 0; z < data.length - 1; z++) {
            // Render a triangle strip for each 'strip'.
            glBegin(GL_TRIANGLE_STRIP);

            for (int x = 0; x < data[z].length; x++) {
                // Take a vertex from the current strip
                //glTexCoord2f(0, 0);
                //GL20.glUseProgram(0);

                glVertex3f(x, data[z][x], z);
                // Take a vertex from the next strip
                //glTexCoord2f(1, 1);
                glVertex3f(x, data[z + 1][x], z + 1);
               /*
         glColor3f(0.9f, 0.9f, 0.9f);
         glBegin(GL_QUADS);
         glTexCoord2f(0, 1); // put before every vertex
         glVertex3f(-50,0 ,-50);
         glTexCoord2f(1, 1);
         glVertex3f(50, 0 ,-50);
         glTexCoord2f(1, 0);
         glVertex3f(50, 0 ,50);
         glTexCoord2f(0, 0);
         glVertex3f(-50, 0 ,50);
         glEnd();
                */
            }
            glEnd();
        }
        glEndList();
    }

    public static void setUpShaders() {
        shaderProgram = ShaderLoader.loadShaderPair("res/landscape.vs", "res/landscape.fs");
        glUseProgram(shaderProgram);
        glActiveTexture(GL_TEXTURE0);
        glBindTexture(GL_TEXTURE_2D, lookupTexture);
        glUniform1i(glGetUniformLocation(shaderProgram, "lookup"), 0);
        glActiveTexture(GL_TEXTURE1);
        glBindTexture(GL_TEXTURE_2D, textureTerrain);
        glUniform1i(glGetUniformLocation(shaderProgram, "terrain"), 1);
    }

    private static void cleanUp(boolean asCrash) {
        glUseProgram(0);
        glDeleteProgram(shaderProgram);
        glDeleteLists(heightmapDisplayList, 1);
        glBindTexture(GL_TEXTURE_2D, 0);
        glDeleteTextures(lookupTexture);
        System.err.println(GLU.gluErrorString(glGetError()));
        Display.destroy();
        System.exit(asCrash ? 1 : 0);
    }

    private static void setUpMatrices() {
        camera.applyPerspectiveMatrix();
    }

    private static void setUpStates() {
        camera.applyOptimalStates();
        glPointSize(1);
        // Enable the sorting of shapes from far to near
        glEnable(GL_DEPTH_TEST);
        // Set the background to a blue sky colour
        glClearColor(0, 0.75f, 1, 1);
        // Remove the back (bottom) faces of shapes for performance
        glEnable(GL_CULL_FACE);
    }

    private static void update() {
        Display.update();
        Display.sync(60);
    }

    private static void enterGameLoop() {
        while (!Display.isCloseRequested()) {
            render();
            input();
            update();

            //TODO

            //TODO
        }
    }

    private static void setUpDisplay() {
        try {
            Display.setDisplayMode(new DisplayMode(WINDOW_DIMENSIONS[0], WINDOW_DIMENSIONS[1]));
            Display.setVSyncEnabled(true);
            Display.setTitle(WINDOW_TITLE);
            Display.create();
        } catch (LWJGLException e) {
            e.printStackTrace();
            cleanUp(true);
        }
    }

    public static void main(String[] args) {
        setUpDisplay();
        setUpStates();
        setUpHeightmap();
        setUpShaders();
        //setUpPhysics();
        setUpMatrices();
        enterGameLoop();
        cleanUp(false);
    }

}

0 个答案:

没有答案