glulookat "resets" after movement (with android)

Question

here's my problem: I'm making a pool game in android and I want to make the camera rotate freely around the center of the table. The thing is that when I stop my movement it looks like the glulookat resets itself because I only see the same thing ver and over again. If somebody knows a way on how to solve this or another way to do what I watn to do i'd be REALLY appreciated

This is my renderer class:

public void onDrawFrame(GL10 gl) {


    // Redraw background color
    gl.glClear(GL10.GL_COLOR_BUFFER_BIT | GL10.GL_DEPTH_BUFFER_BIT);

    // Set GL_MODELVIEW transformation mode
    gl.glMatrixMode(GL10.GL_MODELVIEW);

    gl.glLoadIdentity();   // reset the matrix to its default state



    // Screen position to angle conversion
    theta = (float) ((360.0/screenHeight)*mMoveY*3.0);    //3.0 rotations possible
    phi = (float) ((360.0/screenWidth)*mMoveX*3.0);

    // Spherical to Cartesian conversion.  
    // Degrees to radians conversion factor 0.0174532
    eyeX = (float) (r * Math.sin(theta/**0.0174532*/) * Math.sin(phi/**0.0174532*/));
    eyeY = (float) (r * Math.cos(theta/**0.0174532*/));
    eyeZ = (float) (r * Math.sin(theta/**0.0174532*/) * Math.cos(phi/**0.0174532*/));

    // Reduce theta slightly to obtain another point on the same longitude line on the sphere.

    eyeXtemp = (float) (r * Math.sin(theta/**0.0174532*/-dt) * Math.sin(phi/**0.0174532*/));
    eyeYtemp = (float) (r * Math.cos(theta/**0.0174532*/-dt));
    eyeZtemp = (float) (r * Math.sin(theta/**0.0174532*/-dt) * Math.cos(phi/**0.0174532*/));

    // Connect these two points to obtain the camera's up vector.
    upX=eyeXtemp-eyeX;
    upY=eyeYtemp-eyeY;
    upZ=eyeZtemp-eyeZ;

    // Set the view point
    GLU.gluLookAt(gl,       eyeX, eyeY, eyeZ,       0,0,0,      upX, upY, upZ);

and here's my onTouch method in my activity class:

 public boolean onTouchEvent(MotionEvent e) {

    float x = e.getX();
    float y = e.getY();

    switch (e.getAction()) {
    case MotionEvent.ACTION_MOVE:

        float dx = x - mPreviousX;
        float dy = y - mPreviousY;

        // reverse direction of rotation above the mid-line
        /*if (y > getHeight() / 2) {
            dx = dx * -1 ;
        }

        // reverse direction of rotation to left of the mid-line
        if (x < getWidth() / 2) {
            dy = dy * -1 ;
        }*/

        mRenderer.mMoveX = dx * TOUCH_SCALE_FACTOR/100;
        mRenderer.mMoveY = dy * TOUCH_SCALE_FACTOR/100;

        requestRender();
    }

    mPreviousX = x;
    mPreviousY = y;
    return true;
}

Geobits · Answer 1 · 2012-06-22T05:33:33.327

0

When you do the math, you're using mMoveX and mMoveY. It looks like you should be adding those to other, more persistent x/y variables instead.

Something like:

mCamX += mMoveX;
mCamY += mMoveY;
theta = (float) ((360.0/screenHeight)*mCamY*3.0);    //3.0 rotations possible
phi = (float) ((360.0/screenWidth)*mCamX*3.0);

edited Jun 22 '12 at 05:33

answered Jun 22 '12 at 04:12

Geobits

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Still does the exact same thing, thanks anyway, I think the problem is that somehow my gluLookAt parameters reset themselves therefore always coming back to the initial position (0,0,0). Thanks anyway – ThargtG Jul 04 '12 at 21:23

glulookat "resets" after movement (with android)

1 Answers1