Question

I am working on a sample game demo in which i just put an image in canvas and on android device sensor changes the canvas translate and move for appropriate position. I want to translate canvas just on y-axis (up-down), and rotate it on x-axis. but when i rotate the canvas first time my y-axis coordinates changes and the transformation done on x-axis.

I know the problem with angle of the canvas rotation and calculation of new x,y coordinates but i don’t know how to do it.

this is the sample code:

in my activity class

@Override
public void onSensorChanged(int sensor, float[] values) {
    // TODO Auto-generated method stub

              rotateX = values[0]; 
    translateY = values[1];
    Game.setDirection(rotateX,translateY);
}

now in Game view class in onDraw() method

canvas.rotate(rotateX, imageCenterX, imageCenterY);
canvas.translate(0,translateY);

Thanx in advance.

Answer 1

I solved my problem.

I just swap the method of canvas.

Like

canvas.translate(0,translateY); 
canvas.rotate(rotateX, imageCenterX, imageCenterY); 

Then it works fine.