我有一个简单的Square with openGL es 1和Android 1.5。广场被画在屏幕的中央。
我希望当用户按下屏幕或在屏幕上移动手指时，方块会移动到该位置。为了做到这一点，我尝试使用GLuUnProject，我试图获得与用手指触摸的窗口XY坐标匹配的opengl坐标（将多边形转换为将来的多边形），并且我正在写入坐标logcat中。
我接收的坐标不是真正的坐标，是错误的坐标。例如，此logcat表示屏幕右侧的水平移动：
11-07 15:54:37.221: DEBUG/XXXXXXXXX(213): X: -0.003236022
11-07 15:54:37.221: DEBUG/XXXXXXXXX(213): Y: -0.047979668
11-07 15:54:37.241: DEBUG/XXXXXXXXX(213): X: -0.003236022
11-07 15:54:37.251: DEBUG/XXXXXXXXX(213): Y: -0.047807075
11-07 15:54:39.110: DEBUG/XXXXXXXXX(213): X: 0.03469036
11-07 15:54:39.110: DEBUG/XXXXXXXXX(213): Y: 0.04418271
11-07 15:54:43.021: DEBUG/XXXXXXXXX(213): X: -0.029469538
11-07 15:54:43.021: DEBUG/XXXXXXXXX(213): Y: -0.034172554
11-07 15:54:43.051: DEBUG/XXXXXXXXX(213): X: -0.026708115
11-07 15:54:43.051: DEBUG/XXXXXXXXX(213): Y: -0.034172554
11-07 15:54:43.081: DEBUG/XXXXXXXXX(213): X: -0.018596433
11-07 15:54:43.081: DEBUG/XXXXXXXXX(213): Y: -0.034172554
11-07 15:54:43.111: DEBUG/XXXXXXXXX(213): X: -0.013073588
11-07 15:54:43.111: DEBUG/XXXXXXXXX(213): Y: -0.034172554
11-07 15:54:43.141: DEBUG/XXXXXXXXX(213): X: -0.0039263717
11-07 15:54:43.141: DEBUG/XXXXXXXXX(213): Y: -0.033999965
11-07 15:54:43.162: DEBUG/XXXXXXXXX(213): X: -0.0011649576
11-07 15:54:43.162: DEBUG/XXXXXXXXX(213): Y: -0.033827372
11-07 15:54:43.191: DEBUG/XXXXXXXXX(213): X: 7.335304E-4
11-07 15:54:43.191: DEBUG/XXXXXXXXX(213): Y: -0.033654787
这是源代码：
public class MySurfaceView extends GLSurfaceView implements Renderer {
private float INITIAL_Z = -35.0f;
private Context context;
private Square square;
private float xrot; //X Rotation
private float yrot; //Y Rotation
private float zrot; //Z Rotation
private float z = INITIAL_Z; //Profundidad en el eje Z
private float x = 0.0f; //eje X
private float y = 0.0f; //eje Y
private MatrixGrabber mg = new MatrixGrabber(); //create the matrix grabber object in your initialization code
byte horizontal=-1; //0: LEFT 1:CENTER 2:RIGHT
byte vertical=-1; //0: TOP 1:CENTER 2:BOTTOM
float startX=-1;
float startY=-1;
float xMovement=0.0f;
float yMovement=0.0f;
private boolean movement_mode=false;
public MySurfaceView(Context context, Bitmap image, int width, byte horizontal, byte vertical) {
super(context);
this.context = context;
setEGLConfigChooser(8, 8, 8, 8, 16, 0); //fondo transparente
getHolder().setFormat(PixelFormat.TRANSLUCENT); //fondo transparente
//Transformamos esta clase en renderizadora
this.setRenderer(this);
//Request focus, para que los botones reaccionen
this.requestFocus();
this.setFocusableInTouchMode(true);
square = new Square(image);
this.horizontal=horizontal;
this.vertical=vertical;
}
public void onSurfaceCreated(GL10 gl, EGLConfig config) {
MyGl=gl;
gl.glDisable(GL10.GL_DITHER); //dithering OFF
gl.glEnable(GL10.GL_TEXTURE_2D); //Texture Mapping ON
gl.glShadeModel(GL10.GL_SMOOTH); //Smooth Shading
gl.glClearDepthf(1.0f); //Depth Buffer Setup
gl.glEnable(GL10.GL_DEPTH_TEST); //Depth Testing ON
gl.glDepthFunc(GL10.GL_LEQUAL);
gl.glClearColor(0,0,0,0); //fondo transparente
gl.glHint(GL10.GL_PERSPECTIVE_CORRECTION_HINT, GL10.GL_NICEST);
//Cargamos la textura del cubo.
square.loadGLTexture(gl, this.context);
}
public void onDrawFrame(GL10 gl) {
//Limpiamos pantalla y Depth Buffer
gl.glClear(GL10.GL_COLOR_BUFFER_BIT | GL10.GL_DEPTH_BUFFER_BIT);
gl.glLoadIdentity();
//Dibujado
gl.glTranslatef(x, y, z); //Move z units into the screen
//gl.glScalef(0.8f, 0.8f, 0.8f); //Escalamos para que quepa en la pantalla
//Rotamos sobre los ejes.
gl.glRotatef(xrot, 1.0f, 0.0f, 0.0f); //X
gl.glRotatef(yrot, 0.0f, 1.0f, 0.0f); //Y
gl.glRotatef(zrot, 0.0f, 0.0f, 1.0f); //Z
//Dibujamos el cuadrado
square.draw(gl);
mg.getCurrentProjection(gl);
mg.getCurrentModelView(gl);
}
//si el surface cambia, resetea la vista, imagino que esto pasa cuando cambias de modo portrait/landscape o sacas el teclado físico en móviles tipo Droid.
public void onSurfaceChanged(GL10 gl, int width, int height) {
if(height == 0) {
height = 1;
}
gl.glViewport(0, 0, width, height); //Reset Viewport
gl.glMatrixMode(GL10.GL_PROJECTION); //Select Projection Matrix
gl.glLoadIdentity(); //Reset Projection Matrix
//Aspect Ratio de la ventana
GLU.gluPerspective(gl, 45.0f, (float)width / (float)height, 0.1f, 100.0f);
gl.glMatrixMode(GL10.GL_MODELVIEW); //Select Modelview Matrix
gl.glLoadIdentity(); //Reset Modelview Matrix
}
public boolean onTouchEvent(MotionEvent event) {
float [] outputCoords=getOpenGLCoords(event.getX(), event.getY(), 0);
x=(outputCoords[0]/outputCoords[3]);
y=(outputCoords[1]/outputCoords[3]);
//z=outputCoords[2]/outputCoords[3];
Log.d("XXXXXXXXX", "X: "+x);
Log.d("XXXXXXXXX", "Y: "+y);
return true; //El evento ha sido manejado
}
public float[] getOpenGLCoords(float xWin,float yWin,float zWin)
{
int screenW=SectionManager.instance.getDisplayWidth();
int screenH=SectionManager.instance.getDisplayHeight();
//CODE FOR TRANSLATING FROM SCREEN COORDINATES TO OPENGL COORDINATES
float [] modelMatrix = new float[16];
float [] projMatrix = new float[16];
modelMatrix=mg.mModelView;
projMatrix=mg.mProjection;
int [] mView = new int[4];
mView[0] = 0;
mView[1] = 0;
mView[2] = screenW; //width
mView[3] = screenH; //height
float [] outputCoords = new float[4];
GLU.gluUnProject(xWin, ((float)screenH)-yWin, zWin, modelMatrix, 0, projMatrix, 0, mView, 0, outputCoords, 0);
return outputCoords;
}
}
答案 0 :(得分：1)
你的价值观似乎很合理。你会得到一个越来越大的x值（绝对值递减的负值）和保持大致相同的y值，这对应于向右移动（假设转换中没有任何非零旋转）管道）。
由于4.7的z平移和-4.8的近似值，得到的0.1 z坐标也是合理的。有了这样的z平移和45度的视野，你得到的x和y值确实应该非常小（我认为大约在[-1,1]左右）。
所以我认为你的代码就像它应该的那样工作。你期望的坐标是什么？请不要对像素的顺序说些什么。