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android move image from one place to another place on different screen size and resolutions

I am new in android. I want to make ludo game. and I sets all things related to this game. but I want to move TOKEN from one place to another for different screens like (Nexus 6, Samsung Note 5, Moto G3, etc...). But issue is that for every screen size (Width x Height) are different. that's why I am not set proper x and y position on screen. I referenced screen Height and Width for taking next position (x and y) on screen to move TOKEN on screen. I am taking static image for Ludo Dashboard. That's why i am not getting how to move.
for example:
My Screen is as below,
from origin position to Home position :
In this situation, for every screens translation was changed. because i am taking reference screen Height and Width for move.
for that code is below,
DisplayMetrics displaymetrics = getResources().getDisplayMetrics();
getWindowManager().getDefaultDisplay().getMetrics(displaymetrics);
this.constant.Height = displaymetrics.heightPixels;
this.constant.Width = displaymetrics.widthPixels;
private float getheight(float val) {
return (this.constant.Height * val) / 800;
}
private float getwidth(float val) {
return (this.constant.Width * val) / 480;
}
ObjectAnimator animTranslateY = ObjectAnimator.ofFloat(img,
"translationY", blue_1.getY() + getheight(67));
animTranslateY.setDuration(GameConstants.DURATION);
ObjectAnimator animTranslateX = ObjectAnimator.ofFloat(img,
"translationX", blue_1.getX() + getwidth(128));
animTranslateX.setDuration(GameConstants.DURATION);
AnimatorSet anim = new AnimatorSet();
anim.addListener(new Animator.AnimatorListener() {
#Override
public void onAnimationStart(Animator animator) {
}
#Override
public void onAnimationEnd(Animator animator) {
}
#Override
public void onAnimationCancel(Animator animator) {
}
#Override
public void onAnimationRepeat(Animator animator) {
}
});
anim.play(animTranslateX);
anim.play(animTranslateY);
anim.start();
from Home to Common Rout :
In this situation, its work fine. bt for different screen its moving differ.
So, my question is that How can i move and what should be reference for move image form one position to another position. I takes too many time for this. Please help me.

So, I tried to come up with a solution that uses simple unitary method to solve your problem. I am not sure if it works, I did not try it by coding it actually!
I am assuming that you have set the background static image to scale its size (width) to 100% of the screen, your static image is a square(usually a ludo board is). Also I am considering here that screenwidth is smaller than screenheight. If it is the other way around then exchange the formulae symbols.
let
screenH = screen height in pixels;
screenW = screen width in pixels;
bgW = width of staticbackgroundimage in pixels;
bgH = height of staticbackgroundimage in pixels;
so now, if you want to move 'p' pixels in the background static ludo image horizontally then let us say you will have to move x pixels on the screen. x can be calculated as follows:
x= p*screenW/bgW;
Also, if you want to move 'q' pixels in the background static ludo image vertically then let us say you will have to move y pixels on the screen. y can be calculated as follows:
image height on the screen will be(in pixels):
screenHimage=bgH*screenW/bgW;
y=q*screenHimage/bgH;
So now move x and y pixels on the screen if you want to move p and q pixels in the original image.
I hope this works.

MPAndroid - snapping x position when scrolling

After few hours of trying I'm looking for some hints on how to add snap-scroll mechanism to MPAndroid. Basically I want the 5 visible bars to align so they are fully visible and centered. I now imported the library source code because it looks like there's no other way to change the code in computeScroll (BarLineChartTouchListener).
Edit:
To clarify - I'm showing around 20 bars but chart is zoomed so user can scroll horizontally. What bothers me it is not getting aligned automatically so first visible bar might be clipped in half. I'm looking for snapping effect where it will round the position to the nearest multiplication of the bar width, leaving 5 fully visible bars.

I ended up adding the following function in BarLineChartBase.java. I know it's far from elegant, but seems to do the job. It's limited to targetApi > 11, because of the ValueAnimator. For lower API (which I don't cater for) you might need to have a look at nineoldandroids or some other animation loop technique.
#TargetApi(Build.VERSION_CODES.HONEYCOMB)
public void alignX() {
int count = this.getValueCount();
int xIndex = this.getLowestVisibleXIndex() + Math.round( (this.getHighestVisibleXIndex() - this.getLowestVisibleXIndex()) / 2.0f );
float xsInView = this.getXAxis().getValues().size() / this.getViewPortHandler().getScaleX();
Transformer mTrans = this.getTransformer(YAxis.AxisDependency.LEFT);
float[] pts = new float[] { xIndex - xsInView / 2f, 0 };
mTrans.pointValuesToPixel(pts);
final Matrix save = new Matrix();
save.set(this.getViewPortHandler().getMatrixTouch());
final float x = pts[0] - this.getViewPortHandler().offsetLeft();
final int frames = 20;
ValueAnimator valueAnimator = new ValueAnimator().ofInt(0, frames);
valueAnimator.setDuration(500);
valueAnimator.addUpdateListener(new ValueAnimator.AnimatorUpdateListener() {
int prev = -1;
#Override
public void onAnimationUpdate(ValueAnimator animation) {
if( (int) animation.getAnimatedValue() > prev ) {
save.postTranslate( -x / (float)frames, 0);
BarLineChartBase.this.getViewPortHandler().refresh(save, BarLineChartBase.this, true);
}
prev = (int) animation.getAnimatedValue();
}
});
valueAnimator.start();
}
I trigger it at the end of computeScroll function in BarLineChartTouchListener.
I kept names of variables as I copied code from functions like MoveViewJob, ViewPortHandler etc. Since it's only aligning in x axis - I removed Y axis calculations and used zeros instead. Any optimizations welcome, especially from the author #PhilippJahoda.

Converting Camera Coordinates to Custom View Coordinates

I am trying to make a simple face detection app consisting of a SurfaceView (essentially a camera preview) and a custom View (for drawing purposes) stacked on top. The two views are essentially the same size, stacked on one another in a RelativeLayout. When a person's face is detected, I want to draw a white rectangle on the custom View around their face.
The Camera.Face.rect object returns the face bound coordinates using the coordinate system explained here and the custom View uses the coordinate system described in the answer to this question. Some sort of conversion is needed before I can use it to draw on the canvas.
Therefore, I wrote an additional method ScaleFacetoView() in my custom view class (below) I redraw the custom view every time a face is detected by overriding the OnFaceDetection() method. The result is the white box appears correctly when a face is in the center. The problem I noticed is that it does not correct track my face when it moves to other parts of the screen.
Namely, if I move my face:
Up - the box goes left
Down - the box goes right
Right - the box goes upwards
Left - the box goes down
I seem to have incorrectly mapped the values when scaling the coordinates. Android docs provide this method of converting using a matrix, but it is rather confusing and I have no idea what it is doing. Can anyone provide some code on the correct way of converting Camera.Face coordinates to View coordinates?
Here's the code for my ScaleFacetoView() method.
public void ScaleFacetoView(Face[] data, int width, int height, TextView a){
//Extract data from the face object and accounts for the 1000 value offset
mLeft = data[0].rect.left + 1000;
mRight = data[0].rect.right + 1000;
mTop = data[0].rect.top + 1000;
mBottom = data[0].rect.bottom + 1000;
//Compute the scale factors
float xScaleFactor = 1;
float yScaleFactor = 1;
if (height > width){
xScaleFactor = (float) width/2000.0f;
yScaleFactor = (float) height/2000.0f;
}
else if (height < width){
xScaleFactor = (float) height/2000.0f;
yScaleFactor = (float) width/2000.0f;
}
//Scale the face parameters
mLeft = mLeft * xScaleFactor; //X-coordinate
mRight = mRight * xScaleFactor; //X-coordinate
mTop = mTop * yScaleFactor; //Y-coordinate
mBottom = mBottom * yScaleFactor; //Y-coordinate
}
As mentioned above, I call the custom view like so:
#Override
public void onFaceDetection(Face[] arg0, Camera arg1) {
if(arg0.length == 1){
//Get aspect ratio of the screen
View parent = (View) mRectangleView.getParent();
int width = parent.getWidth();
int height = parent.getHeight();
//Modify xy values in the view object
mRectangleView.ScaleFacetoView(arg0, width, height);
mRectangleView.setInvalidate();
//Toast.makeText( cc ,"Redrew the face.", Toast.LENGTH_SHORT).show();
mRectangleView.setVisibility(View.VISIBLE);
//rest of code

Using the explanation Kenny gave I manage to do the following.
This example works using the front facing camera.
RectF rectF = new RectF(face.rect);
Matrix matrix = new Matrix();
matrix.setScale(1, 1);
matrix.postScale(view.getWidth() / 2000f, view.getHeight() / 2000f);
matrix.postTranslate(view.getWidth() / 2f, view.getHeight() / 2f);
matrix.mapRect(rectF);
The returned Rectangle by the matrix has all the right coordinates to draw into the canvas.
If you are using the back camera I think is just a matter of changing the scale to:
matrix.setScale(-1, 1);
But I haven't tried that.

The Camera.Face class returns the face bound coordinates using the image frame that the phone would save into its internal storage, rather than using the image displayed in the Camera Preview. In my case, the images were saved in a different manner from the camera, resulting in a incorrect mapping. I had to manually account for the discrepancy by taking the coordinates, rotating it counter clockwise 90 degrees and flipping it on the y-axis prior to scaling it to the canvas used for the custom view.
EDIT:
It would also appear that you can't change the way the face bound coordinates are returned by modifying the camera capture orientation using the Camera.Parameters.setRotation(int) method either.

android translateAnimation setDuration() doesn't work

I'm trying to create a translate animation to an imageView. The animation works but not according to the value I'm putting in the setDuration()
This is the code
/* flipping the images out of the screen */
float outOfScreenX = currentImageLocationX * DRAG_ACTION_SCREEN_BOUNDS_THREASHOLD;
float outOfScreenY = currentImageLocationY * DRAG_ACTION_SCREEN_BOUNDS_THREASHOLD;
translate = new TranslateAnimation(0, outOfScreenX, 0, outOfScreenY);
long velocity = Math.max(Math.abs((int) vTracker.getXVelocity()), Math.abs((int) vTracker.getYVelocity())) / 10;
velocity = (long) Math.min(velocity, 200);
translate.setDuration(velocity);
translate.setFillAfter(true);
mDragView.clearAnimation();
mDragView.startAnimation(translate);
imageStack.removeView(mOriginator);
The value of "velocity" derived from the vTracker, the speed of the user's touch on the view. It's always between 200-600 proximately, but the view moves much faster than this(and also a little flickering but this is another topic).

How to prepare curve translate animation for android?

There are 4 types of animations in android - rotate, alpha,scale and translate.
I want to prepare curved translate animation.
Is it possible.?

What Android version do you use? Since API level 11 you can use custom Animators which can easily implement your curve translation.
If you use a version below that there is afaik only the possibility to manually concatenate multiple linear translations using the translate animation and setting animation listeners
EDIT:
Example:
View view;
animator = ValueAnimator.ofFloat(0, 1); // values from 0 to 1
animator.setDuration(5000); // 5 seconds duration from 0 to 1
animator.addUpdateListener(new ValueAnimator.AnimatorUpdateListener()
{
#Override
public void onAnimationUpdate(ValueAnimator animation) {
float value = ((Float) (animation.getAnimatedValue()))
.floatValue();
// Set translation of your view here. Position can be calculated
// out of value. This code should move the view in a half circle.
view.setTranslationX((float)(200.0 * Math.sin(value*Math.PI)));
view.setTranslationY((float)(200.0 * Math.cos(value*Math.PI)));
}
});
I hope it works. Just copied & pasted (and shortened and changed) the code from one of my apps.

Here are the animators I use:
Purpose: Move View "view" along Path "path"
Android v21+:
// Animates view changing x, y along path co-ordinates
ValueAnimator pathAnimator = ObjectAnimator.ofFloat(view, "x", "y", path)
Android v11+:
// Animates a float value from 0 to 1
ValueAnimator pathAnimator = ValueAnimator.ofFloat(0.0f, 1.0f);
// This listener onAnimationUpdate will be called during every step in the animation
// Gets called every millisecond in my observation
pathAnimator.addUpdateListener(new ValueAnimator.AnimatorUpdateListener() {
float[] point = new float[2];
#Override
public void onAnimationUpdate(ValueAnimator animation) {
// Gets the animated float fraction
float val = animation.getAnimatedFraction();
// Gets the point at the fractional path length
PathMeasure pathMeasure = new PathMeasure(path, true);
pathMeasure.getPosTan(pathMeasure.getLength() * val, point, null);
// Sets view location to the above point
view.setX(point[0]);
view.setY(point[1]);
}
});
Similar to: Android, move bitmap along a path?

Consider the following web link. It is a game in C. You need to isolate the projectile() function and try to understand the variables defined within it. Once you get that try implementing it in your own code.
http://www.daniweb.com/software-development/c/code/216266