I have to move the sprite along the path that is drawn onTouch.For that I'm using Path and PathModifier
case MotionEvent.ACTION_UP:
int historySize = pSceneTouchEvent.getMotionEvent().getHistorySize();
pointX = new float[historySize];
pointY = new float[historySize];
for (int i = 1; i < historySize; i++) {
pointX[i] = pSceneTouchEvent.getMotionEvent().getHistoricalX(i);
pointY[i] = pSceneTouchEvent.getMotionEvent().getHistoricalY(i);
}
path = new path(pointX,pointY);
PathModifier pathModifier = new PathModifier(2.5f, path);
pathModifier.setRemoveWhenFinished(true);
sprite1.clearEntityModifiers();
sprite1.registerEntityModifier(pathModifier);
break;
Its giving me error as path needs at least 2 way points.
Any idea why so?
Normally this shouldn't happen, since a motion event is very often more than just one coordinate. Maybe you should test if the historySize is really bigger than 2. In addition you can add the sprites starting coordinates, otherwise the sprite would "jump" towards the first touch point (but that wasn't your question).
This isn't actually different – just another possibility:
path= new Path(historySize);
for (int i = 0; i < historySize; i++) {
float x = pSceneTouchEvent.getMotionEvent().getHistoricalX(i);
float y = pSceneTouchEvent.getMotionEvent().getHistoricalY(i);
path.to(x,y);
}
In addition I noticed you start your for-loop with int i=1 so if your historySizeis 2, the loop iterates only one times!
EDIT
I couldn't find the problem, but I found a solution:
Instead of using the motionEvent history, save the coordinates of the toucheEvent on the go as the touchEventoccurs:
ArrayList<Float> xCoordinates; // this is where you store all x coordinates of the touchEvents
ArrayList<Float> yCoordinates; // and here will be the y coordinates.
onSceneTouchEvent(TouchEvent sceneTouchEvent){
switch(sceneTouchEvent.getAction()){
case (TouchEvent.ACTION_DOWN):{
// init the list every time a new touchDown is registered
xCoordinates = new ArrayList<Float>();
yCoordinates = new ArrayList<Float>();
break;
}
case (TouchEvent.ACTION_MOVE): {
// while moving, store all touch points in the lists
xCoordinates.add(sceneTouchEvent.getX());
yCoordinates.add(sceneTouchEvent.getY());
break;
}
case (TouchEvent.ACTION_UP): {
// when the event is finished, create the path and make the sprite move
// instead of the history size use the size of your own lists
Path path = new Path(xCoordinates.size());
for (int i = 0; i < xCoordinates.size(); i++) {
path.to(xCoordinates.get(i), yCoordinates.get(i)); // add the coordinates to the path one by one
}
// do the rest and make the sprite move
PathModifier pathModifier = new PathModifier(2.5f, path);
pathModifier.setAutoUnregisterWhenFinished(true);
sprite1.clearEntityModifiers();
sprite1.registerEntityModifier(pathModifier);
break;
}
}
I tested this on my phone (which does not run in debug mode) and it works fine. But to make sure that no Exception will be thrown, you should always test if the xCoordinates list is bigger than 1. Although it is very probable that it is.
Well I hope it helps at least to go around your original problem. I noticed that some methods are named differently (e.g. setAutoUnregisterWhenFinished(true);) I guess you are using AndEngine GLES1 ? I use GLES2, so when a method has another name in my code, don't worry and just look for the equivalent in GLES1 (I didn't rename them because, the code works as it is)
Christoph
Related
I'm creating a Android game with Unity and I'm trying to make an object to follow my finger. This is the code I'm using.
for (int i = 0; i < Input.touchCount; i++)
{
RaycastHit2D hit = Physics2D.Raycast(Camera.main.ScreenToWorldPoint(Input.touches[i].position), Vector2.zero);
Vector3 touchPosition = Camera.main.ScreenToWorldPoint(Input.touches[i].position);
if (Input.GetTouch(i).phase == TouchPhase.Moved && hit.collider != null)
{
transform.position = new Vector2(touchPosition.x, touchPosition.y + sizeY);
}
}
I put the collider bellow the object and I added the size of the object to the Y, so it appears above my finger.
The problem is that if I move my finger slightly faster, I lose the object, that stays behind. Since the object lags behind, if I move my finger faster I end up out of the collider area and the object just stop moving.
The only way I found that works is to get rid of the Raycast thing and make the object follow the touch anywhere in the screen (I don't like that).
I just want to know if this is the best I can get from Unity and Android or if there a is way to make an object follow the finger in a one-by-one movement, with precision, without lag.
I'm testing on a Samsung Galaxy S8 just with the object and nothing else.
You are not alone with this issue. Unity's Input API is frame-rate based and may not keep with the speed of the touch movement on the screen. If you're working on something that requires fast response based on the touch on the screen, use the new Unity's InputSystem. This API is still in experimental mode.
Its Touchscreen class can be used to access the touch on the screen. Your current code should translate into something like below:
public int touchIndex = 0;
void Update()
{
Touchscreen touchscreen = UnityEngine.Experimental.Input.Touchscreen.current;
if (touchscreen.allTouchControls[touchIndex].ReadValue().phase != PointerPhase.None &&
touchscreen.allTouchControls[touchIndex].ReadValue().phase == PointerPhase.Moved)
{
Vector2 touchLocation = touchscreen.allTouchControls[touchIndex].ReadValue().position;
RaycastHit2D hit = Physics2D.Raycast(Camera.main.ScreenToWorldPoint(touchLocation), Vector2.zero);
Vector3 touchPosition = Camera.main.ScreenToWorldPoint(touchLocation);
transform.position = new Vector2(touchPosition.x, touchPosition.y + sizeY);
}
}
I want to moove two objects smoothely at Touching.
Here is my Code:
for(int i = 0; i <96; i++){
Asstest.rect_pipe_down.y--);
}
This should move the rect 96 pixels down (SMOOTH)
But it just close without smoothed...
What did I wrong?
If you Touch, the pipes should close, but not hard, smooth should they close.
But with following code they just close hard...
Here is the full touched code:
if(Gdx.input.isTouched()){
Assets.rect_pipe_down.y = 512 - 320/2;
Assets.rect_pipe_up.y = -320 + 320/2;
for (int i = 0; i < 96; i++){
smoothTime = TimeUtils.millis();
if(TimeUtils.millis() - smoothTime > 10) {
Assets.rect_pipe_down.y--;
Assets.rect_pipe_up.y++;
batch.begin();
batch.draw(Assets.region_pipe_down, Assets.rect_pipe_down.x, Assets.rect_pipe_down.y);
batch.draw(Assets.region_pipe_up, Assets.rect_pipe_up.x, Assets.rect_pipe_up.y);
batch.end();
}
}
closed = true;
}
You cannot do rendering multiple times in one render() call, one call is for drawing exactly one frame. In your current code, the later images simply overwrite the previous ones.
What you could do is have a variable which persists between frames which stores whether or not the pipes are currently closing, a constant for the speed and some condition to tell when they can stop - maybe when they are some given distance from each other, not sure what you would want here. Anyway, that's what I'll use in my example.
Then in the render() method, before drawing anything, you can do this:
if (closing) {
Assets.rect_pipe_down.y -= CLOSE_SPEED * delta;
Assets.rect_pipe_up.y += CLOSE_SPEED * delta;
if (Assets.rect_pipe_down.y - Assets.rect_pipe_up.y < TARGET_DIST) {
Assets.rect_pipe_down.y = Assets.rect_pipe_up.y + TARGET_DIST;
closing = false;
}
}
Here, closing is a variable you set to true when you want them to start closing, the others are constants. You could add some more variables/constants if you want to make sure they end up at a specific height independent on framerate.
I have a 2D game that uses two integer arrays to track x and y coordinates as shown below:
private int gridX[] = { 0,0,0,0,0 }
private int gridY[] = { 0,0,0,0,0 }
The problem is I can have a LOT of objects on the screen that needs to be tracked. Is there a way to add integers / create new blocks as needed? IE in a loop, do something like
gridX[].add(); or something like that. I'm relatively new to java and droid development and I'm having trouble finding a good tutorial or example that shows how to do this without having to initialize the gridX and gridY to sizes of 100 or so.
This is important, as I am about 90% sure that all those unused 0's are causing androids garbage cleanup to lag my application.
Why dont you use an array list instead of an Integer array?
that way you can dynamically add items to the list
ArrayList<Integer> myList = new ArrayList<Integer>();
myList.add(1);
myList.add(2);
Why not also use the Point class?
List<Point> points = new ArrayList<Point>();
points.add(new Point(0, 0));
points.add(new Point(50, 70));
Point point = points.get(1);
Log.d("MyApp", String.format("The point is: (%d, %d)", point.x, point.y);
This way you are keeping track of your x and y coordinates together and there is less opportunity for error.
After getting the calculator application to work I decided to try to create pong. There is a box in the center and two paddles on both ends. The phone is horizontal. I have the box bouncing off the walls and the paddle moves with me moving my finger down. My problem is i want to make it two player and i want to have multiple finger input for the game. I want one finger to move paddle 1 and the other to move paddle 2. So far this is my input code
#Override
public boolean onTouchEvent(MotionEvent ev) {
final int action = ev.getAction();
switch (action) {
case MotionEvent.ACTION_MOVE: {
// Find the index of the active pointer and fetch its position
float p1y = ev.getY();
if(ev.getX()<300)
{
player1y = p1y;
}
if(ev.getX()>300)
{
player2y = p1y;
}
//player1y = p1y;
invalidate();
break;
}
}
return true;
}
it resides in my surfaceview class. How can i modify the input method or completely get rid of it and change it to accomplish my goal? Also sorry about my variables. Eclipse crashes a lot on me and my laptops touch panel tends to move my cursor so shorter variables seemed viable. p1y is the y of the touch. and player1y and player2y is the y positions of the player1 and player2 paddle.
A MotionEvent can hold multiple pointers. Use getPointerCount() to see how many pointers are touching the screen in the current event. There are alternate versions of getX and getY that take an index from 0-getPointerCount() - 1.
In a more complex app you would want to track fingers by pointer ID, but for something this simple where you are using a cutoff point on the screen you could do something like this in your ACTION_MOVE case:
int pointerCount = ev.getPointerCount();
for (int i = 0; i < pointerCount; i++) {
float x = ev.getX(i);
float y = ev.getY(i);
if (x < 300) {
player1y = y;
} else if (x > 300) {
player2y = y;
}
}
This post from the Android Developers Blog might help if you'd like more information: http://android-developers.blogspot.com/2010/06/making-sense-of-multitouch.html
Is there a way to read the points created when drawing a path? It seems silly to me that a path cannot be readable.
Or is it just better to manually write the current finger position to an array?
thanks
You can read as many points as you want from any path.
Example how to read coordinates from the middle of path:
PathMeasure pm = new PathMeasure(myPath, false);
//coordinates will be here
float aCoordinates[] = {0f, 0f};
//get coordinates of the middle point
pm.getPosTan(pm.getLength() * 0.5f, aCoordinates, null);
You can pass any distance from the path start to get point coordinates.
As far as I know, I think that you can't get previously added points, but you can extend Path class and create your own, override add methods, and then store that points in an array or a list or whatever you prefer.
You mentioned finger position in your question. If you are drawing and using motion events, you could add the X and Y positions to an ArrayList during the event where all even indices are X's and odds are Y's. I used this in a couple of drawing apps I created. To recreate the path all you need is a for loop and Path.lineTo().
Also if you have drawn the path to a view with a specific color, say Color.Black, you can use Bitmap.getPixels(...) and create an array {x0,y0,x1,y1,....xn,yn} based off a for loop like
int i = 0;
for(int y = 0; y < bitmap.getHeight(); y++){
for(int x = 0; x < bitmap.getWidth(); x++){
if(pixels[y*bitmap.getWidth()+x] == Color.BLACK){
xy[i] = x;
i++;
xy[i] = y;
i++;
}
}
}
The array xy has all your coordinates.