在 android 帮助上在 opengl 中移动立方体

Question

经过大量的试验和错误，我能够绘制一个立方体和一个立方体前面的瓷砖地图。我添加了输入，这样当您移动手指时，相机就会移动。但现在我想在我的游戏进程中添加下一步。我希望它让我的立方体移动到我在 3d 空间中按手指的位置。听起来有点困难。我想做的是让你用一根手指在地图上滑动相机，用另一根手指双击并移动。到目前为止，我的立方体在原地抖动和摇摆，但没有移动到我想要的位置。当然，我的代码都不是完美的，而且我对 gluunproject 的关注可能远远不正确。这是到目前为止我的代码

立方体创建者和更新代码//其简短

public shapemaker(int x, int y, int z,int width)
{
    centerx =x;
    centery =y;
    centerz =z;



        mysquare1= new square(centerx,centery,centerz-5,1,.0f,.0f,1f,"vert");
        mysquare2= new square(centerx-1,centery,centerz-6f,1,.0f,1.0f,.0f,"side");
        mysquare3= new square(centerx,centery,centerz-7,1,1.0f,.0f,.0f,"vert");
        mysquare4= new square(centerx+1,centery,centerz-6f,1,.0f,.5f,.5f,"side");
        mysquare5= new square(centerx,centery-1,centerz-6f,1,.5f,.5f,.0f,"horiz");
        mysquare6= new square(centerx,centery+1,centerz-6f,1,.5f,.0f,.5f,"horiz");
}

public void updatecube(float x, float y, float z)
{


        centerx =x;
        centery =y;
        centerz =z;

        mysquare1= new square(centerx,centery,centerz-5,1,.0f,.0f,1f,"vert");
        mysquare2= new square(centerx-1,centery,centerz-6f,1,.0f,1.0f,.0f,"side");
        mysquare3= new square(centerx,centery,centerz-7,1,1.0f,.0f,.0f,"vert");
        mysquare4= new square(centerx+1,centery,centerz-6f,1,.0f,.5f,.5f,"side");
        mysquare5= new square(centerx,centery-1,centerz-6f,1,.5f,.5f,.0f,"horiz");
        mysquare6= new square(centerx,centery+1,centerz-6f,1,.5f,.0f,.5f,"horiz");
}

public void drawcube(GL10 gl)
{
    mysquare1.draw(gl);        
    mysquare2.draw(gl);        
    mysquare3.draw(gl);        
    mysquare4.draw(gl);        
    mysquare5.draw(gl);        
    mysquare6.draw(gl);

}
public float getcenterx()
{
    return centerx;
}
public float getcentery()
{
    return centery;
}
public float getcenterz()
{
    return centerz;
}

这是实际的实现代码，它基于谷歌对 opengl 的介绍

class ClearGLSurfaceView extends GLSurfaceView {
    private static final String BufferUtils = null;
    float x =0;
    float y =0;
    float z =0f;
    float prevx=0;
    float prevy=0;
    GL10 mygl;
   // GL gl;
    float mywidth;
    float myheight;








public ClearGLSurfaceView(Context context,float width, float height) {
    super(context);
    mRenderer = new ClearRenderer();
    setRenderer(mRenderer);
    mywidth = width;
    myheight = height;





}
@Override
public boolean onTouchEvent(final MotionEvent event)
{

    queueEvent(new Runnable() {
        // Find the index of the active pointer and fetch its position
        public void run()
        {
            float curx = event.getX();
            float cury = event.getY();
            final int action = event.getAction();
            if(action == MotionEvent.ACTION_MOVE)
            {


            if(curx>prevx)
            {
                  x-=.1f;
            }
            if(curx<prevx)
            {
                  x+=.1f;
            }
            if(cury>prevy)
            {
                  y+=.1f;
            }
            if(cury<prevy)
            {
                  y-=.1f;
            }



            }
            if(action == MotionEvent.ACTION_DOWN)
            {
                // GLU.gluUnProject(winX, winY, winZ, model,
                //       modelOffset, project, projectOffset, view, viewOffset, obj, objOffset)
                vector2d moveto = new vector2d(0,0);
                moveto = mRenderer.getworkcoords(curx,cury);
                Log.i("move to ", "x "+moveto.x+" y "+ moveto.y+" z " + moveto.z);
                mRenderer.updatemoveto(moveto.x, moveto.y);



            }
            prevx= curx;
            prevy = cury;

            mRenderer.updatecamera(x, y, z);
}
 });
    return true;
} 

    ClearRenderer mRenderer;

}

class ClearRenderer Implements GLSurfaceView.Renderer {

       GL10 mygl;
       GL11 mygl11;

       int viewport[] = new int[4];
        float modelview[] = new float[16];
        float projection[] = new float[16];
        float wcoord[] = new float[4];

public void onSurfaceCreated(GL10 gl, EGLConfig config) {

    gl.glClearColor(0.0f, 0.0f, 0.0f, 0.5f);  // OpenGL docs.
    gl.glShadeModel(GL10.GL_SMOOTH);// OpenGL docs.
    gl.glClearDepthf(1.0f);// OpenGL docs.
    gl.glEnable(GL10.GL_DEPTH_TEST);// OpenGL docs.
    gl.glDepthFunc(GL10.GL_LEQUAL);// OpenGL docs.
    gl.glHint(GL10.GL_PERSPECTIVE_CORRECTION_HINT, // OpenGL docs.
                      GL10.GL_NICEST);

    mygl = gl;
    mygl11 = (GL11) gl;
    int index;
    int counter = 0;
    float zcoord = -7.0f;

  mygl11.glGetFloatv(GL11.GL_MODELVIEW_MATRIX, modelview, 0);
  mygl11.glGetFloatv(GL11.GL_PROJECTION_MATRIX, projection, 0);
  mygl11.glGetIntegerv(GL11.GL_VIEWPORT, viewport, 0);

    for(int x=0;x<11;x++)
    {
        for(int y =0;y<10;y++)
        {
            index = tilemap1[y][x];
            if(index==0)
            {
                tiles[counter]=new square(x,y,zcoord,0.5f,1.0f,0.0f,0f,"vert");

            }
            if(index==1)
            {
                tiles[counter]=new square(x,y,zcoord,0.5f,0f,1.0f,0f,"vert");

            }
            if(index==2)
            {
                tiles[counter]=new square(x,y,zcoord,0.5f,0.0f,0.0f,1f,"vert");

            }
            counter++;
        }
    }


}

public vector2d getworkcoords(float width,float height)
{
     float[] depth = new float[1];
     float winx = width;
     float winy =viewport[3]-height;
    //vector2d position = new vector2d(0,0);
    int test = GLU.gluUnProject(winx, winy,0.0f, modelview, 0, projection,
            0, viewport, 0, wcoord, 0);

    vector2d v = new vector2d(0,0);
    v.x = wcoord[0];
    v.y = wcoord[1];
    v.z = wcoord[2];
    return v ;
}

public void onSurfaceChanged(GL10 gl, int w, int h) {
    gl.glViewport(0, 0, w, h);

    gl.glMatrixMode(GL10.GL_PROJECTION);// OpenGL docs.

    gl.glLoadIdentity();// OpenGL docs.

    GLU.gluPerspective(gl, 45.0f,
                               (float) w / (float) h,
                               0.1f, 100.0f);

    gl.glMatrixMode(GL10.GL_MODELVIEW);// OpenGL docs.

    gl.glLoadIdentity();// OpenGL docs.
}

public float movetox;
public float movetoy;
float currentposx;
float currentposy;

public void updatemoveto(float x , float y) { 移动毒素=x； 移动玩具 = y； } public void onDrawFrame(GL10 gl) {

    gl.glClearColor(mRed, mGreen, mBlue, 1.0f);
    gl.glClear(GL10.GL_COLOR_BUFFER_BIT | GL10.GL_DEPTH_BUFFER_BIT);

    currentposx = mycube.getcenterx();
    currentposy = mycube.getcentery();

    float x = movetox -currentposx;
    float y = movetoy - currentposy;
    double angle = Math.atan2(y, x);
    double mx =.5f*  Math.cos(angle);
    double my = .5f* Math.sin(angle);



    double mmx = mx+ currentposx;
    double mmy = my+ currentposy;

    mycube.updatecube((float)(mmx), (float)(mmy),0);  


    mycube.drawcube(gl);

    for(int i = 0;i<110;i++)
    {

            tiles[i].draw(gl);

    }


}

public void setColor(float r, float g, float b) {
    mRed = r;
    mGreen = g;
    mBlue = b;
}
public void updatecamera(float myx, float myy, float myz)
{

    mygl.glLoadIdentity();// OpenGL docs.
    GLU.gluLookAt(mygl, myx, myy, myz, myx, myy, myz-10, 0, 1, 0);

}


private float mRed;
private float mGreen;
private float mBlue;


int tilemap1[][] = {
        {0,0,0,0,0,0,0,0,0,0,0},
        {0,1,2,1,1,1,1,1,1,1,0},
        {0,1,2,1,1,1,1,1,1,1,0},
        {0,1,2,1,1,1,1,1,1,1,0},
        {0,1,2,2,2,1,1,1,1,1,0},
        {0,1,1,1,2,1,1,1,1,1,0},
        {0,1,1,1,2,1,1,1,1,1,0},
        {0,1,1,1,2,1,1,1,1,1,0},
        {0,1,1,1,2,2,1,1,1,1,0},
        {0,0,0,0,0,0,0,0,0,0,0},
};
square[] tiles = new square[110];

shapemaker mycube = new shapemaker(0,0,0,1);

}

我没有包含创建方法和暂停方法。我还想获得有关设计代码结构的建议，因为我的实现还远远不够完美。

简而言之。我希望帮助弄清楚如何修改我编写的代码，以使立方体移动到我按下的位置。以及如何改进代码

谢谢

Answer 1

首先，

您不需要在每次移动时重新创建顶点。这是非常复杂的任务，并且会降低帧速率（FPS）。在您的代码中您有模型矩阵。通常它负责模型的平移、缩放旋转（示例中的网格、立方体）。在常见情况下，您必须转换模型矩阵，然后转换多个模型、投影和视图矩阵，您将获得设备屏幕的矩阵。然后通过顶点位置与该矩阵相乘，您将得到顶点的正确位置。

你可以看看这个问题/答案