android – 如何在OpenGL ES 1.1上填充不同纹理的立方体的每一面？

我发现很多教程,但是没有一个解释清楚如何在每个面上放置不同的纹理,没有一个给出了如何做的简单的代码示例.

我的实际代码(来自nehe的例子)在每个面上绘制一个具有相同纹理的立方体：

public class Cube {

/** The buffer holding the vertices */
private FloatBuffer vertexBuffer;
/** The buffer holding the texture coordinates */
private FloatBuffer textureBuffer;
/** The buffer holding the indices */
private ByteBuffer indexBuffer;

/** Our texture pointer */
private int[] textures = new int[1];

/** 
 * The initial vertex deFinition
 * 
 * Note that each face is defined,even
 * if indices are available,because
 * of the texturing we want to achieve 
 */ 
private float vertices[] = {
                    //Vertices according to faces
                    -1.0f,-1.0f,1.0f,//Vertex 0
                    1.0f,//v1
                    -1.0f,//v2
                    1.0f,//v3

                    1.0f,//...
                    1.0f,};

/** The initial texture coordinates (u,v) */   
private float texture[] = {         
                    //Mapping coordinates for the vertices
                    0.0f,0.0f,};

/** The initial indices deFinition */   
private byte indices[] = {
                    //Faces deFinition
                    0,1,3,2,//Face front
                    4,5,7,4,6,//Face right
                    8,9,11,8,10,//... 
                    12,13,15,12,14,16,17,19,18,20,21,23,22,};

/**
 * The Cube constructor.
 * 
 * Initiate the buffers.
 */
public Cube() {
    //
    ByteBuffer byteBuf = ByteBuffer.allocateDirect(vertices.length * 4);
    byteBuf.order(ByteOrder.nativeOrder());
    vertexBuffer = byteBuf.asFloatBuffer();
    vertexBuffer.put(vertices);
    vertexBuffer.position(0);

    //
    byteBuf = ByteBuffer.allocateDirect(texture.length * 4);
    byteBuf.order(ByteOrder.nativeOrder());
    textureBuffer = byteBuf.asFloatBuffer();
    textureBuffer.put(texture);
    textureBuffer.position(0);

    //
    indexBuffer = ByteBuffer.allocateDirect(indices.length);
    indexBuffer.put(indices);
    indexBuffer.position(0);
}

/**
 * The object own drawing function.
 * Called from the renderer to redraw this instance
 * with possible changes in values.
 * 
 * @param gl - The GL Context
 */
public void draw(GL10 gl) {
    //Bind our only prevIoUsly generated texture in this case
    gl.glBindTexture(GL10.GL_TEXTURE_2D,textures[0]);

    //Point to our buffers
    gl.glEnableClientState(GL10.GL_VERTEX_ARRAY);
    gl.glEnableClientState(GL10.GL_TEXTURE_COORD_ARRAY);

    //Set the face rotation
    gl.glFrontFace(GL10.GL_ccw);

    //Enable the vertex and texture state
    gl.glVertexPointer(3,GL10.GL_FLOAT,vertexBuffer);
    gl.glTexCoordPointer(2,textureBuffer);

    //Draw the vertices as triangles,based on the Index Buffer information
    gl.glDrawElements(GL10.GL_TRIANGLES,indices.length,GL10.GL_UNSIGNED_BYTE,indexBuffer);

    //disable the client state before leaving
    gl.gldisableClientState(GL10.GL_VERTEX_ARRAY);
    gl.gldisableClientState(GL10.GL_TEXTURE_COORD_ARRAY);
}

/**
 * Load the textures
 * 
 * @param gl - The GL Context
 * @param context - The Activity context
 */
public void loadGLTexture(GL10 gl,Context context) {
    //Get the texture from the Android resource directory
    InputStream is = context.getResources().openRawResource(R.drawable.nehe);
    Bitmap bitmap = null;
    try {
        //BitmapFactory is an Android graphics utility for images
        bitmap = BitmapFactory.decodeStream(is);

    } finally {
        //Always clear and close
        try {
            is.close();
            is = null;
        } catch (IOException e) {
        }
    }

    //Generate one texture pointer...
    gl.glGenTextures(1,textures,0);
    //...and bind it to our array
    gl.glBindTexture(GL10.GL_TEXTURE_2D,textures[0]);

    //Create Nearest Filtered Texture
    gl.glTexParameterf(GL10.GL_TEXTURE_2D,GL10.GL_TEXTURE_MIN_FILTER,GL10.GL_NEAREST);
    gl.glTexParameterf(GL10.GL_TEXTURE_2D,GL10.GL_TEXTURE_MAG_FILTER,GL10.GL_LINEAR);

    //Different possible texture parameters,e.g. GL10.GL_CLAMP_TO_EDGE
    gl.glTexParameterf(GL10.GL_TEXTURE_2D,GL10.GL_TEXTURE_WRAP_S,GL10.GL_REPEAT);
    gl.glTexParameterf(GL10.GL_TEXTURE_2D,GL10.GL_TEXTURE_WRAP_T,GL10.GL_REPEAT);

    //Use the Android glutils to specify a two-dimensional texture image from our bitmap
    glutils.texImage2D(GL10.GL_TEXTURE_2D,bitmap,0);

    //Clean up
    bitmap.recycle();
}
}