防止在OpenGL ES中随Spite动画一起滚动背景

Question

在使用这里描述的无尽道路算法之后，我还实现了与其一起滚动的墙。 我有驻留在屏幕中央的人的步行动画。

我做了什么：背景滚动根据无尽的路算法

什么问题来实现？ 这个人的形象也像无尽的道路一样滚动。

我想要的：人的动画不应该滚动，但背景应该滚动。

我沿着使用方法...... “gl.glMatrixMode（GL10.GL_TEXTURE）”在openglES与矩阵玩尝试，但得到的是背景滚动停止，但是动画是成功的。

我知道我错了，但我无法找到我的错误。

这里是我的代码：

public class GLSquare { 

FloatBuffer fVertexBuffer, mTextureBuffer; 
ByteBuffer mColorBuff; 
ByteBuffer mIndexBuff; 
int[] textures = new int[1]; 
public boolean useMipMapping = true; 
float _numTextures = 2; 
float incrementTex; 
private float _acceleration; 
long startTime; 
float vertices [] = { 
     -2.0f,2.0f,0.0f,   //byte index 0 
     2.0f, 2.0f,0.0f,   //byte index 1 
     -2.0f, -2.0f,0.0f,   //byte index 2 
     2.0f,-2.0f,0.0f,   //byte index 3 

    };     

    float textureCoord[] = { 

      0.0f,incrementTex, 
      1.0f,incrementTex, 
      0.0f,_numTextures+incrementTex, 
      1.0f,_numTextures+incrementTex 

    }; 


byte indices[] = {0, 1, 2, 
     1, 2, 3 }; 


public GLSquare() { 

    // TODO Auto-generated constructor stub  
    ByteBuffer byteBuffer = ByteBuffer.allocateDirect(vertices.length * 4); // 4 vertices, 3 co-ordinates(x,y and z) 4 for converting in float 
    byteBuffer.order(ByteOrder.nativeOrder()); 
    fVertexBuffer = byteBuffer.asFloatBuffer(); 
    fVertexBuffer.put(vertices); 
    fVertexBuffer.position(0); 

    ByteBuffer byteBuffer2 = ByteBuffer.allocateDirect(textureCoord.length * 4); 
    byteBuffer2.order(ByteOrder.nativeOrder()); 
    mTextureBuffer = byteBuffer2.asFloatBuffer(); 
    Log.i("texture", "tex corrrrd " + String.valueOf(textureCoord)); 
    mTextureBuffer.put(textureCoord); 
    mTextureBuffer.position(0); 

    startTime = System.currentTimeMillis(); 
} 

public void draw(GL10 gl){ 
    gl.glFrontFace(GL11.GL_CW); 
    gl.glEnableClientState(GL10.GL_VERTEX_ARRAY); 
    gl.glVertexPointer(3,GL10.GL_FLOAT, 0, fVertexBuffer); 

    gl.glEnable(GL10.GL_TEXTURE_2D); 

    /** for the repetition of road.*/ 
_acceleration += -0.005f * (float)System.currentTimeMillis()-startTime;    
    _acceleration = Math.max(_acceleration, 0.002f); 
    gl.glMatrixMode(GL10.GL_TEXTURE); 
    gl.glTranslatef(0, _acceleration, 0); 
    gl.glMatrixMode(GL10.GL_MODELVIEW); 
    incrementTex -= _acceleration; 

    gl.glBindTexture(GL10.GL_TEXTURE_2D, textures[0]); //4 
    gl.glTexCoordPointer(2, GL10.GL_FLOAT,0, mTextureBuffer); //5 
    gl.glEnableClientState(GL10.GL_TEXTURE_COORD_ARRAY); 

    gl.glDrawArrays(GL10.GL_TRIANGLE_STRIP, 0, 4); //7 

    gl.glFrontFace(GL11.GL_CCW); 

    gl.glDisableClientState(GL10.GL_VERTEX_ARRAY); 
    gl.glDisableClientState(GL10.GL_TEXTURE_COORD_ARRAY); 


} 

public void createSquareTexture(GL10 gl, Context context, int resource) 
{ 
    Bitmap bitmap = BitmapFactory.decodeResource(context.getResources(), resource); 
    gl.glGenTextures(1, textures, 0); 
    gl.glBindTexture(GL10.GL_TEXTURE_2D, textures[0]); 

    gl.glTexParameterf(GL10.GL_TEXTURE_2D, GL10.GL_TEXTURE_MIN_FILTER, GL10.GL_LINEAR); 
    gl.glTexParameterf(GL10.GL_TEXTURE_2D, GL10.GL_TEXTURE_MAG_FILTER, GL10.GL_LINEAR); 


    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); 

    gl.glTexParameterf(GL10.GL_TEXTURE_2D, GL10.GL_REPEAT, GL10.GL_CLAMP_TO_EDGE); 

    GLUtils.texImage2D(GL10.GL_TEXTURE_2D, 0, bitmap, 0); 

    bitmap.recycle(); 
} 

    } 

这里是在渲染类使用的方法......

TextureRegion keyFrame; 
public void present(float deltaTime) { 

    GL10 gl = glGraphics.getGL(); 

    gl.glClearColor(0f, 0.2f, 0.2f, 1.0f); 
    gl.glClear(GL10.GL_COLOR_BUFFER_BIT | GL10.GL_DEPTH_BUFFER_BIT); 

    loadTheWalls(gl); 

    guiCamera.setViewportAndMatrices(); 

    gl.glEnable(GL10.GL_TEXTURE_2D); 


    gl.glEnable(GL10.GL_BLEND); 
    gl.glBlendFunc(GL10.GL_SRC_ALPHA, GL10.GL_ONE_MINUS_SRC_ALPHA); 

    batcher.beginBatch(texture); 
      keyFrame = straightWalk.getKeyFrame(stickMan.straightWalkTime, Animation.ANIMATION_LOOPING); 
     drawTheManMethod(); 
    batcher.endBatch(); 

} 

public void loadTheWalls(GL10 gl){ 
    /** 
    * 
    * Code for the back scrolling of roads and walls 
    * Three squares are taken and the textures are repeated on the respective square. 
    * Only two textures are taken here, One for the wall and other for the road. 
    * Wall textures are rotated accordingly ap per usage. 
    * 
    * */  
    gl.glMatrixMode(GL10.GL_PROJECTION); 
    gl.glLoadIdentity(); 
    GLU.gluPerspective(gl, 67, glGraphics.getWidth() 
        /(float) glGraphics.getHeight(), 1f, 100f); 

      gl.glMatrixMode(GL10.GL_MODELVIEW); 
      gl.glLoadIdentity(); 
      gl.glEnable(GL10.GL_DEPTH_TEST); 


    /**Square used as a road*/ 
     gl.glPushMatrix(); 
     gl.glLoadIdentity(); 
     gl.glTranslatef(0.0f, -1.0f, -4.0f); // Translate to wallpos and into the screen (NEW) 
     gl.glRotatef(-80, 1, 0, 0); 
     mSquare2.draw(gl);     // Draw Square (NEW) 
     gl.glPopMatrix(); 


     /**Square used as a left wall*/ 
     gl.glPushMatrix(); 
     gl.glLoadIdentity(); 
     gl.glTranslatef(-2.0f, 0.0f, -4.0f); // Translate to wallpos and into the screen (NEW) 
     gl.glRotatef(-90, 0, 1, 0); 
     gl.glRotatef(90, 0, 0, 1); 
     mSquare3.draw(gl);     // Draw Square (NEW) 
     gl.glPopMatrix(); 

     /**Square used as a right wall*/ 
     gl.glPushMatrix(); 
     gl.glLoadIdentity(); 
     gl.glTranslatef(1.8f, 0.0f, -4.0f); // Translate to wallpos and into the screen (NEW) 
     gl.glRotatef(-85, 0, 1, 0); 
     gl.glRotatef(90, 0, 0, 1); 
     mSquare1.draw(gl);     // Draw Square (NEW) 
     gl.glPopMatrix(); 

} 




public void pause() { 

} 


public void resume() { 
    GL10 gl = glGraphics.getGL(); 

    texture = new Texture(((GLGame)game), "twocharacter.png"); 

    straightWalk = new Animation(0.2f, 
      new TextureRegion(texture, 0, 96, 96, 96), 
      new TextureRegion(texture, 96, 96, 96, 96), 
      new TextureRegion(texture, 96*2, 96, 96, 96), 
      new TextureRegion(texture, 96*3, 96, 96, 96), 
      new TextureRegion(texture, 96*4, 96, 96, 96), 
      new TextureRegion(texture, 96*5, 96, 96, 96), 
      new TextureRegion(texture, 96*6, 96, 96, 96), 
      new TextureRegion(texture, 96*7, 96, 96, 96) 
       ); 


    int resId2 = R.drawable.buildngs; 
     mSquare1.createSquareTexture(gl, getBaseContext(), resId2); 

     int resId3 = R.drawable.buildngs; 
     mSquare3.createSquareTexture(gl, getBaseContext(), resId3); 

     int resId4 = R.drawable.path; 
     mSquare2.createSquareTexture(gl, getApplication(), resId4); 
} 

这里有一个更好的理解图像。

Answer 1

在GLSquare中创建一个名为texturePos的字段。

private float texturePos = 0.0f; 

这个替换您的加速段：

/** for the repetition of road.*/ 
_acceleration += -0.005f * (float)System.currentTimeMillis()-startTime;    
_acceleration = Math.max(_acceleration, 0.002f); 
texturePos += acceleration; 
gl.glMatrixMode(GL10.GL_TEXTURE); 
gl.glPushMatrix(); 
gl.glTranslatef(0, texturePos, 0); 
gl.glMatrixMode(GL10.GL_MODELVIEW); 
incrementTex -= _acceleration; 

通知我们通过texturePos而不是_acceleration也texturePos平移由_acceleration递增之前，在当前矩阵压入堆栈。

然后在您的抽奖方法的末尾添加以下内容：

gl.glMatrixMode(GL10.GL_TEXTURE); 
gl.glPopMatrix(); 
gl.glMatrixMode(GL10.GL_MODELVIEW); 

所以我们跳出旧的纹理矩阵从堆栈所以它恢复正常。

---

另外，您也可以只叫

gl.glMatrixMode(GL10.GL_TEXTURE); 
gl.glLoadIdentity(); 

绘制你的人面前，但第一种方法更好，因为它会工作在更多情况下。