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How can I make the width of a Constraint Layout negative?

I'm not sure if this is possible, or If I am approaching this challenge wrong. I am making a 2D Platformer, so when you hit the edge of the screen(Width), a new portion of the map would appear. Currently, I made single Images for each Portion of the map. Problem is, on larger devices, this would leave a lot of blank screen, and the Image would only fit a specific device.
Now I am wondering, can I make my ImageView (MAP) at a negative X value then when the character hits the edge, the map would move right (X would go higher).
I am using XML (Java is also fine), and I have NO CLUE how to approach this.

Since you are using constraint layout, you need to set android:layout_width="0dip".
This will fit any image to its screen width.(Image width should be greater than screen horizontal width).
Apply some conditions something like,
If image width < screen width then call next image to remaining screen, else call next image for entire screen.
Hope it helps for code-flow.
:)

You could use android:translationX or Android:translationY which actually support negative values. But in your particular case I think you are trying to use a nail clipper to cut your hair... You are using stuff that are not designed for that purpose. Using multiple big Image views can become a performance issue (I don't know about your particular case), I recommended you instead to be brave and make your own wiew and paint it dynamically (it can sound difficult but I'm sure will be easier than what you are trying), or make a comprehensive googling for a view meant for what you want.
Specifically for games you should try andengine lib or something like that, believe me... It would be easier in the end and you may earn something new :)

An alternative solution is to draw a layout (e.g. RelativeLayout) larger than your screen size, with an equal amount of padding on all sides.
For example, if you want to make a 50dp x 50dp ImageView appear from off the right hand side of the screen, your RelativeLayout would be 100dp taller and wider than your screen (50dp on each side). You could then position your ImageView at the far right of the RelativeLayout, and move it onto the visible area at will. So drawing something at -20dp, would actually be drawing it at 30dp in this example.
Programmatically getting the screen size and resizing a layout is very straightforward, and this approach would let you control your map loading in the manner you described.

Change camera behavior in jMonkey

I am writing a program that is supposed to display 3D point clouds. For this purpose, I am using the jMonkeyEngine. Unfortunately, I do not like the default camera behavior of jMonkey. Especially the mouse dragging and mouse wheel do not really do what I want. What I want is them to behave like in the pcd viewer of the PointCloudLibrary.
Mouse wheel: Should be faster, and the the effect of the turning directions should be switched.
Mouse dragging: In jMonkey it seems like mouse dragging changes the camera viewing direction in the world. I am not sure what exactly happens in the pcd viewer, but I believe the camera is moved through the world while fixating the centroid of the displayed point cloud.
How can I change the behavior of the camera to fullfil my wishes? :)

1.
In the simpleInit() method (where 100 is an abritrary number):
getFlyByCamera().setZoomSpeed(100);
getFlyByCamera().setDragToRotate(true);
Note, that zooming doesn't actually change the position of the camera, just the FOV.
2.
The normal behavior of the camera is to rotate around its own axis. By offseting the location of the camera as well, the effect you want can be achieved. In simpleUpdate():
cam.setLocation(cam.getDirection().negate().multLocal(cam.getLocation().length()));
I consider the answer to the second question a bit of a quick hack. But it does the trick.

Android - Tracking Real-Time Touch Events to Draw

I need your help.
I am trying to implement a paint system with live-tracking, you may think: “Live-tracking? What do you mean?”
So I am implementing a solution to track each touch movement on the display, so I can decide, if I want to paint on a specific spot or not, this decision must be in real-time, right when the user touches the display.
There will be some images where the user should paint the inner white space inside of the respective shape; figure 1 shows an example of this shape.
The user should paint the inside of the shape in a specific direction/order; I still don’t know how I can configure this order/direction in the image. An example of a specific order would be like the one showing on figure 2.
So I want the user to paint starting from the zone 1 to the zone 6, do you understand? I don’t want the user to be able to paint the zone 1 and then zone 3, without painting the zone 2 first…
In the end, I would have the shape filled, like the figure 3 shows. The arrows are there just to show the right direction of drawing.
It’s not just about direction, the specific spots on the image matter, there will be different types of images, and I can’t use only the direction.
How can I determine the specific spots in an image with a specific order to be painted?
The only idea that came to my mind, would be some kind of training mode, where I (the developer) would draw the image with the order I want, and the system behind would create virtual points on the code, with a small distance between each of them. Then I would have an array with all the “spots” saved with the order I draw them, do you understand?
I don’t know if this will work, and if it will be fast enough to travel my array of “spots” when the user is trying to draw on the image? Because I want this to work on real-time, the system should check if it’s a valid spot to draw right when the user touches the display…
Do you think it will work? Do you have some recommendations about this? What are the best structures and stuff like that? I am not asking for written code, I just need some guidelines.
I think I explained my problem well, if you have any question please ask me.
Thank you very much in advance!

if all your shapes are lines you can treat the points you want your users to "touch" as squares, every time an ACTION_MOVE event is happening, check if the finger is touching the next point. You can make the size of the squares whatever suits you, like 48dp or 92dp or the width/height of the shape you are drawing.
You said you don't want any code so I assume you know how to do this (if not reply and I will post code too).
Also you didn't mention what happens if the user goes out of the shape, if you want the user to continue drawing until they lift their finger then this way is good, when the ACTION_UP event happens check if the last point is touched (assuming it can only be touched if all others are touched like explained above).
Here is an image if you'd like to have a visual guide:
Obviously if you it this way you have to calculate the positions of each point you will have, I doubt there is any way to automate this.
If you need any more help or you need some code please reply and I will post some! :D

Changing Mouse Sensitivity in Java

How do you get the sensitivity of a mouse, change it, and then apply it to the mouse?
-Progress removed, showed the speed of clicking instead of the speed of moving-
I have researched this "everywhere", but there is nothing on this subject.

First of all I think arg0.getXOnScreen will give You the absolute x coordinate of the mouse, not the old position as You're assuming by defining variable named oldX. getX should give you the position within the panel or (sth like widget i do not know the api you are using). The second thing is... what do You mean 'sensitivity of mouse' Do you want to change global system settings for mouse from java ? I do not think it is even possible. Look here this will require You to add jni lib to project and invoke some native libs, so You make your code platform dependent.

You would probably have to tinker with the Robot class and listnening for mouse events. So you'd have to listen for mouse pressed events and after that use robot to move the mouse 3x more pixels than the mouse is actually moving, then you'd have to do a mouse up event via the Robot class, reposition the mouse to the original position followed by a mouse down event via the robot.
See how this can be problematic? This would be extremely use case driven and not something to do generically. I've been doing Java a long time so I could probably pull it off but it is not something a novice could probably do because other issues would come up that need resolution during the debugging process.
Noticed this thread when dealing with a 3d API that rotates the view WAY TO SLOW.

How to draw a cross on Google Maps?

I have following task - I need to draw on Google Maps a cross with certain coordinates. I know how can I do it using ItemOverlay but I think that there is means without using a custom marker. I need simple black cross with my coordinates. Please, tell me, is it possible?
UPDATE: I don't want to use ItemOverlay because I need to make a custom drawable for it and I hope there is simple android internal elements for it.

I'm sorry, but using Overlays seems to be the only way of drawing any line on Google Maps.

You could draw an ImageView right over the google maps view (with absolute positioning using margins). But then you'd have to take care of coord conversion (and reacting to user scrolling, zooming the map) "by hand".
I think you could also use SurfaceView fully aligned to google maps view and draw your marker right on it.
But both solutions are pretty much overkill; you're better off using ItemizedOverlay unless you have a really good reason no to - in which case you might wanna add some info on what's the reason, maybe we'll find you a nice solution to that one :)