Codename One - Start drag operation on longPointerPress - drag-and-drop

Is there a way to start drag operation in not predefined way?
Abstract example using long pointer press event:
public void longPointerPress (int x, int y) {
methodToStartDragAndDropOperation (this, blablabla);
}

I don't think there is a way to do this with the current API, we support drag regions which are draggable areas within the component but not long press gestures right now.
A hack that might work is using setDraggable(false) and in longPress doing something like:
super.pointerReleased(x, y);
setDraggable(true);
super.pointerPressed(x, y);
super.pointerDragged(x, y + convertToPixels(3));

Related

Unity: Ignore collision of a plateform if jump to it from below. Using ContactFilter & rigidBody.Cast()

I am able to avoid a collision between my player and my entire plateform with the use of contactFilter2D.SetLayerMask() + rigidBody2D.Cast(Vector2, contactFilter, ...);
But I don't find a way to avoid the collision only if my player try to acces to the plateform from below it (with a vertical jump).
I'm pretty sure I should use the contactFilter2D.setNormalAngle() (after specify the minAngle and maxAngle) but no matter the size of my angles, I can't pass threw it.
This is how I initialize my contactFilter2D.
protected ContactFilter2D cf;
void Start () {
cf.useTriggers = false;
cf.minNormalAngle = 0;
cf.maxNormalAngle = 180;
cf.SetNormalAngle(cf.minNormalAngle, cf.maxNormalAngle);
cf.useNormalAngle = true;
}
void Update () {
}
I use it with
count = rb.Cast(move, contactFilter, hitBuffer, distance + shellRadius);
Any ideas ? If you want more code, tell me. But I don't think it will be usefull to understand the matter.
unity actualy has a ready made component for this: it is a physics component called "Platform Effector 2D" if you drag and drop it on your platform it will immediately work the way you want, and it has adjustable settings for tweaking the parameters. hope this helps!

Move a particular sprite to a target position after clicking the button in unity 4.6

I have just started unity. I have 4 Images(sprites) aligned in a grid.
As soon as i touch the particular chocolate, its texture changes[I wrote a code for that]. There is a button on screen.After pressing the button, I want to move only those chocolates whose texture has been changed.
I know the following move code but i don't know how to use it here.
void Update () {
float step=speed*Time.deltaTime;
transform.position=Vector3.MoveTowards(transform.position,target.position,step);
}
I just don't know to move that particular sprite whose texture is changed. Thanks
Do you want to be moving the sprites over the course of a duration or instantly?
If it's over the course of a duration I suggest you use Lerp. You can Lerp between two Vector.3's in a time scale. Much cleaner and once learned a very useful function.
Code examples below:
http://docs.unity3d.com/ScriptReference/Vector3.Lerp.html
http://www.blueraja.com/blog/404/how-to-use-unity-3ds-linear-interpolation-vector3-lerp-correctly
However if you want to move it instantly. This can be done very easily using the built in localPosition properties which you can set in or outside the object.
Set your changed sprites Bool moved property (create this) to true on click (if you're using Unity 4.6 UI canvas then look at the IClick interfaces available for registering mouse activity in canvas elements) and then when you press the button, loop through a list in a handler file which contains all your button texture objects and move those that the moved property is set to true for.
foreach(GameObject chocolate in chocolateList)
{
if (chocolate.moved == true)
{
gameObject.transform.localPosition.x = Insert your new x position.
gameObject.transform.localPosition.y = Insert your new y position.
}
}
However please do clarify your intentions so I can help further.
EDIT 1:
I highly suggest you make your sprites an object in the canvas for absolute work clarity. This makes a lot of sense as your canvas can handle these type of things much better. Use Image and assign your image the sprite object (your chocolate piece), define it's width and height and add a script to it called "ChocolatePiece", in this script create two public variables, bool moved and int ID, nothing else is required from this script. Save this new object as your new prefab.
Once you've done this in a handler script attached to an empty gameobject in your canvas make a list of gameobjects:
List<GameObject> chocolatePieces = new List<GameObject>();
You'll want to at the top of your handler script define GameObject chocolatePiece and attach in your inspector the prefab we defined earlier. Then in Start(), loop the size of how many chocolate pieces you want, for your example lets use 4. Instantiate 4 of the prefabs you defined earlier as gameobjects and for each define their properties just like this:
Example variables:
int x = -200;
int y = 200;
int amountToMoveInX = 200;
int amountToMoveInY = 100;
Example instantiation code:
GameObject newPiece = (GameObject)Instantiate(chocolatePiece);
chocolatePieces.Add(newPiece);
newPiece.GetComponent<ChocolatePiece>().ID = i;
newPiece.transform.SetParent(gameObject.transform, false);
newPiece.name = ("ChocolatePiece" + i);
newPiece.GetComponent<RectTransform>().localPosition = new Vector3(x, y, 0);
From this point add to your positions (x by amountToMoveInX and y by amountToMoveInY) for the next loop count;
(For the transform.position, each count of your loop add an amount on to a default x and default y value (the position of your first piece most likely))
Now because you have all your gameobjects in a list with their properties properly set you can then access these gameobjects through your handler script.

How can i turn the camera to left and right in unity for a sphere?

updated CODE .. the problem is that i cant move the ball only if i hold the E button than i use WASD or arrows to move the ball...and when i hold Q the camera 2 activates and i can move the ball with WASD or arrows...but with the right axis for that angle...is like ballance that game... i want to not hold the E or Q just to change the camera and move the ball corecctly for that angle with the right axis for the ball but not holding the cameras button
using UnityEngine;
using System.Collections;
public class controlPlayer : MonoBehaviour {
public float viteza ; // this is speed
;
void Start(){
}
void Update()
{
if(Input.GetKey(KeyCode.Q) ) // if i hold Q the camera 2 activates and with WASD i can move the ball
{
float miscaOrizontal = Input.GetAxis("Horizontal");
float miscaVertical = Input.GetAxis("Vertical");
Vector3 miscare = new Vector3(miscaVertical,0.0f,(-miscaOrizontal)); //also here i chande the axis for the camera 2
rigidbody.AddForce(miscare * viteza * Time.deltaTime);
}
if(Input.GetKey(KeyCode.E) ) // here when i press E the camera 1 activates and alos i can move the ball if i keep pressing E
{ float miscaOrizontal2 = Input.GetAxis("Horizontal");
float miscaVertical2 = Input.GetAxis("Vertical");
Vector3 miscare2 = new Vector3(miscaOrizontal2,0.0f,miscaVertical2); // here are the controls for the ball for the camera ..i had to change the axis here..
rigidbody.AddForce(miscare2 * viteza * Time.deltaTime);
}
}
}
}
Alright, so if I'm understanding you correctly, you want the ball to move in relation to which direction the camera is currently facing. As well as you don't want to have to hold down "Q" or "E" while you move your ball with WASD controls.
So there are a few things that I'd like to mention here, so we'll take them one at a time. First off, you shouldn't have "AddForce" inside of an Update call. Update is called every frame whenever it can. It's great for input, but generally you want to call it in "FixedUpdate" instead. It provides a better response across many devices. If you leave it in update, you can get inaccurate physics results, and missed collisions. There's a lot out there on this subject, so if you want to know more about it, then just google for a little while.
As for the code side, you want to store a reference to what camera you're using to avoid having to hold these buttons down.
What I mean is:
private Camera referencedCamera = null;
private void Start()
{
referencedCamera = camera1;
}
private void Update()
{
if(Input.GetKey(KeyCode.Q)) referencedCamera = camera2;
else if(Input.GetKey(KeyCode.E)) refrencedCamera = camera1;
}
This way you can reference which camera is being used, rather than a key input. Something else to look into is the "State Design Pattern". Below is a video over the "State Design Pattern." That is a great video tutorial series that Derek Banas put up on design patterns, extremely recommend watching them, but the state pattern could potentially solve this problem for you as well. So that should take care of not having to hold the button down in order to make the move. More or less, the buttons will now allow you to just switch which camera is currently being used.
https://www.youtube.com/watch?v=MGEx35FjBuo
So now that that is solved, you want to transform the input that you currently have, and you want to put it in terms of hte camera that is currently being used. So to avoid rewriting a lot of the code over and over again, just know that these two code snippets should be pieced together into one. So "referencedCamera" should be already defined in the code I'm about to write:
private void FixedUpdate()
{
if(referencedCamera != null)
{
float miscaOrizontal = Input.GetAxis("Horizontal");
float miscaVertical = Input.GetAxis("Vertical");
Vector3 miscare = referencedCamera.transform.TransformDirection(
new Vector3(miscaVertical, 0.0f, -miscaOrizontal));
rigidbody.AddForce(miscare * viteza * Time.deltaTime);
}
}
So now with this, is it's the same code, but there is a call to the referenced cameras transform to take the vector 3 from the input and put it in relation to the camera instead, and add the new relational vector to the object.
I also want to recommend you looking into events rather than if checks in the update function, but that is beyond the scope of the question. Hope this helps and any questions, don't hesitate to ask.
EDIT
After further discussion, we came across something that should also be mentioned. If your camera that you are referencing is angled, the force will be applied in that angle, so keep that in mind. If it is pointed towards an object downward, then forward relative to the camera will apply a force downward, and not entirely in what you may consider the forward direction. Thought it was worth mentioning.

visual lag of the moving picture in Unity3D. How to make it smoother?

I make a game in Unity3D (+2D ToolKit) for iOS.
It is 2d runner/platformer with side view. So on screen is moving background and obstacles. And we control up/down the main character to overcome obstacles.
The problem is that the moving picture has a visual lag. In other words, it moves jerkily or creates the tail area of the previous frames on iOS-devices. In XCode the number of frames is 30 and over.
I have objects 'plain' with the following script:
public class Move: Monobehavior
{
private float x;
public float Speed = 128.0f;
void Start()
{
x = transform.position.x;
}
void Update()
{
x += Time.DeltaTime *Speed;
Vector3 N = transform.position;
N.x = mathf.FloorInt(x);
transform.position = N;
}
}
The question is how to make the move of background smoother, without jerks and flicker on screen while playing? Maybe the problem is in framerate parameter.
Can anybody help me to find a solution?
I'd say it's the use of the FloorInt function which will move the background only in steps of 1 which is rather not smooth. It should get better when you comment that line out. Do you have any special reason why you are doing the FloorInt there?
The use of floor will definitely hurt your performance. Not only is it one more thing to calculate, but it is actually removing fidelity by removing decimals. This will definalty make the movement look 'jerky'. Also, update is not always called on the same time inteval, depending on what else is happening during that frame, so using Time.delaTime is highly recommended. Another thing, you do not need to set variables for x and Vector3 N, when you can update the transoms position like the code below. And if you have to, you sill only need to create one variable to update, and set your position to it. The code below just updates the players x position at a given rate, based on the amount of time that has passes since the last update. There should be no 'jerky' movement. (Unless you have a serious framerate drop);
public class Move: Monobehavior
{
public float Speed = 128.0f;
void Update()
{
transform.position =
(transform.position.x + (speed*Time.DeltaTime),
transform.position.y,
transform.position.z);
}
}

MouseDown events are not delivered until MouseUp when a Drag Source is present

I have a mouse listener. It has some code to respond to mouseUp and mouseDown events. This works correctly.
However, as soon as I add a DragSource, my mouseDown event is no longer delivered -- until I release the mouse button!
This is trivial to reproduce - below is a simple program which contains a plain shell with just a mouse listener and a drag listener. When I run this (on a Mac), and I press and hold the mouse button, nothing happens - but as soon as I release the mouse button, I instantly see both the mouse down and mouse up events delivered. If I comment out the drag source, then the mouse events are delivered the way they should be.
I've searched for others with similar problems, and the closest I've found to an explanation is this:
https://bugs.eclipse.org/bugs/show_bug.cgi?id=26605#c16
"If you hook drag detect, the operating system needs to eat mouse events until it determines that you have either dragged or not."
However, I don't understand why that's true -- why must the operating system eat mouse events to determine if I have a drag or not? The drag doesn't start until I have a mouse -move- event with the button pressed.
More importantly: Can anyone suggest a workaround? (I tried dynamically adding and removing my drag source when the mouse is pressed, but then I couldn't get drag & drop to function properly since it never saw the initial key press - and I can't find a way to programmatically initiate a drag.)
Here's the sample program:
package swttest;
import org.eclipse.swt.dnd.DND;
import org.eclipse.swt.dnd.DragSource;
import org.eclipse.swt.dnd.DragSourceEvent;
import org.eclipse.swt.dnd.DragSourceListener;
import org.eclipse.swt.events.MouseEvent;
import org.eclipse.swt.events.MouseListener;
import org.eclipse.swt.widgets.Display;
import org.eclipse.swt.widgets.Shell;
public class SwtTest {
public static void main(String[] args) {
final Display display = new Display();
final Shell shell = new Shell(display);
shell.addMouseListener(new MouseListener() {
public void mouseUp(MouseEvent e) {
System.out.println("mouseUp");
}
public void mouseDown(MouseEvent e) {
System.out.println("mouseDown");
}
public void mouseDoubleClick(MouseEvent e) {
System.out.println("mouseDoubleClick");
}
});
DragSourceListener dragListener = new DragSourceListener() {
public void dragFinished(DragSourceEvent event) {
System.out.println("dragFinished");
}
public void dragSetData(DragSourceEvent event) {
System.out.println("dragSetData");
}
public void dragStart(DragSourceEvent event) {
System.out.println("dragStart");
}
};
DragSource dragSource = new DragSource(shell, DND.DROP_COPY | DND.DROP_MOVE);
dragSource.addDragListener(dragListener);
shell.pack();
shell.open();
while (!shell.isDisposed()) {
if (!display.readAndDispatch())
display.sleep();
}
display.dispose();
}
}
To answer your specific question about why this happens -- on Cocoa we don't consider a drag to have started until the mouse has moved a few pixels. This ensures against 'accidental' drags if you're sloppy with the clicks. On Linux and Win32 the window toolkit can do the drag detection. If you just hold down the button the detection times out and the mouse down is delivered. On Cocoa we have no time out, which is why nothing happens until the drag is detected or a mouse up happens.
That's a lot of detail, but the conclusion is that the behavior is inconsistent, and we should always be able to deliver the mouse down immediately, without waiting for the drag detection to complete.
I don't see a workaround, since this is happening before the Control sees the event.
See this bug which has patches for win32, gtk and cocoa SWT.
I had faced the same problem and found a solution. Once you attach a DragSource to your custom widget, the event loop will be blocked in that widget's mouse down hook and will eat mouse move events to detect a drag. (I've only looked into the GTK code of SWT to find this out, so it may work a little differently on other platforms, but my solution works on GTK, Win32 and Cocoa.) In my situation, I wasn't so much interested in detecting the mouse down event right when it happened, but I was interested in significantly reducing the drag detection delay, since the whole purpose of my Canvas implementation was for the user to drag stuff. To turn off the event loop blocking and built-in drag detection, all you have to do is:
setDragDetect(false);
In my code, I am doing this before attaching the DragSource. As you already pointed out, this will leave you with the problem that you can't initiate a drag anymore. But I have found a solution for that as well. Luckily, the drag event generation is pure Java and not platform specific in SWT (only the drag detection is). So you can just generate your own DragDetect event at a time when it is convenient for you. I have attached a MouseMoveListener to my Canvas, and it stores the last mouse position, the accumulated drag distance and whether or not it already generated a DragDetect event (among other useful things). This is the mouseMove() implementation:
public void mouseMove(MouseEvent e) {
if (/* some condition that tell you are expecting a drag*/) {
int deltaX = fLastMouseX - e.x;
int deltaY = fLastMouseY - e.y;
fDragDistance += deltaX * deltaX + deltaY * deltaY;
if (!fDragEventGenerated && fDragDistance > 3) {
fDragEventGenerated = true;
// Create drag event and notify listeners.
Event event = new Event();
event.type = SWT.DragDetect;
event.display = getDisplay();
event.widget = /* your Canvas class */.this;
event.button = e.button;
event.stateMask = e.stateMask;
event.time = e.time;
event.x = e.x;
event.y = e.y;
if ((getStyle() & SWT.MIRRORED) != 0)
event.x = getBounds().width - event.x;
notifyListeners(SWT.DragDetect, event);
}
}
fLastMouseX = e.x;
fLastMouseY = e.y;
}
And that will replace the built-in, blocking drag detection for you.