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WPF C# wrong mouse coordinates

So im trying to get mouse coordinates from a click on an image, and it gives the wrong coordinates. When i move the mouse to draw, the line appears away from the cursor.
This is the code i use to get the mouse coordinates:
private void ponaredek_MouseDown(object sender, MouseButtonEventArgs e)
{
mouseDown = true;
//x1 = System.Windows.Forms.Control.MousePosition;
x1 = new System.Drawing.Point((int)e.GetPosition(this).X, (int)e.GetPosition(this).Y);
}
x1 is of type System.Drawing.Point (i need the point from drawing, to use in emgucv). What do i have to do to correct the cursor location (i drew where the cursor was)

You want to get the mouse position relative to the Image element, not the Window. So replace
e.GetPosition(this)
by
e.GetPosition((IInputElement)sender)
or
e.GetPosition(ponaredek)
if that is the Image element.
It should look like this:
var pos = e.GetPosition((IInputElement)sender);
x1 = new System.Drawing.Point(pos.X, pos.Y);
Also make sure the Image element's Stretch property is set to None.

Background image of control bugged

I've done a mini test program to prototype a way to drag and drop an image (at the right)(using a button as a support) to a panel (left part)(The current panel background letter are only for test purpose) and to move it inside the panel perimeter.
The image on the moving control is manually drawn during the Paint event :
void bouton_Paint( object sender, PaintEventArgs e )
{
Button but = sender as Button;
Bitmap img = new Bitmap(WindowsFormsApplication1.Properties.Resources.triaxe);
img.MakeTransparent(Color.White);
e.Graphics.DrawImage(img, 0, 0, but.Width, but.Height);
}
As you can see below, during the moving process, the background of the moved control is frezzed. So it is not very pretty
Is it to make the progress smoother ?
Thank you.
This is the code to move my triaxe on the form :
void bouton_MouseUp( object sender, MouseEventArgs e )
{
Button button = sender as Button;
button.Tag = false;
button.BackColor = Color.Transparent;
}
void bouton_MouseMove( object sender, MouseEventArgs e )
{
Button button = sender as Button;
if (button.Tag != null && (bool)button.Tag == true)
{
button.Left += e.X - MouseDownLocation.X;
button.Top += e.Y - MouseDownLocation.Y;
}
}
private Point MouseDownLocation;
void bouton_MouseDown( object sender, MouseEventArgs e )
{
Button button = sender as Button;
MouseDownLocation = e.Location;
button.Tag = true;
button.BackColor = SystemColors.Control;
}

Let's assume you do not want to draw the graphics alone but do want a Control with transparency move on top of another Control.
You have to solve two problems:
Winforms doesn't support transparency well; you have two options:
Either let the system fake it for you
Or do the faking yourself.
For the first it is enough to have a control with a transparent backcolor and an Image or BackgroundImage (depending on the control type) with transparency and then nest the moving control in the background control.
For a simplistic test you can add if (button.Parent != panel1) button.Parent = panel1; to your mousedown code. This will look jumpy but should display transparency correctly. (Don't forget to make the Backcolor transparent; in your code your make it SystemColors.Control.
To fake it yourself you would do exactly what the system does:
You get the target suface in a bitmaps (with DrawToBitmap) and then combine the area the mover currently covers with the image; here getting that area is key.
Then you can set that image as backgroundimage or draw it onto the mover.
The other problem is with the moving code. Here the issue is that when you move the mouse the MouseMove event is triggered and you can move the control. But by moving it the mouse will have moved relativly to the new location and the event will be triggered again leading to flicker an jumpiness!
To avoid this you can test the numbers or use a flag or unregister the move event before setting the location and re-register afterwards.
Also setting the location in one go instead of the two coordinates is a good idea..: button.Location = new Point(button.Left + e.X - MouseDownLocation.X, button.Top + e.Y - MouseDownLocation.Y);
Imo you should still consider drawing just the graphics on On panel.MouseMove and panel.Paint. On panel.MouseUp you can still add a Button to the panel.Controls right there. Both issues are avoided and you are free to add the functionality you want as well..

How can I convert the mouse cursor coordinates when click on pictureBox are to the screen relative mouse cursor coordinates?

In my program I added this code so when I move my mouse all over the screen I will get the mouse cursor coordinates in real time:
Form1 Load:
private void Form1_Load(object sender, EventArgs e)
{
System.Windows.Forms.Timer t1 = new System.Windows.Forms.Timer();
t1.Interval = 50;
t1.Tick += new EventHandler(timer1_Tick);
t1.Enabled = true;;
}
Then the method that get the mouse position:
public static Point GetMousePosition()
{
var position = System.Windows.Forms.Cursor.Position;
return new Point(position.X, position.Y);
}
Then the timer1 tick event:
private void timer1_Tick(object sender, EventArgs e)
{
label1.Text = string.Format("X={0}, Y={1}", GetMousePosition().X, GetMousePosition().Y);
}
Then I ran some application and moved the mouse over a specific location on the screen where the application window is and I found this coordinates:
358, 913
Now I have in my program a listBox with items each item present application screenshot. And if I click on the pictureBox for example in this case on the BATTLEFIELD 3 area I get the mouse cursor coordinates according to the pictureBox area.
So I did:
Point screenCoordinates;
Point pictureBoxSnapCoordinates;
private void pictureBoxSnap_MouseDown(object sender, MouseEventArgs e)
{
screenCoordinates = pictureBoxSnap.PointToScreen(e.Location);
pictureBoxSnapCoordinates = e.Location;
}
Now when I click in the pictureBox at the same location as I found the coordinates 358, 913 but on the pictureBox so the results are:
screenCoordinates 435, 724
pictureBoxSnapCoordinates 23,423
The screenCoordinates isn't the same coordinates as I found with the mouse move 358, 913 it's not even close. There is a big difference between 358,913 and 437,724

e.Location is relative to the Control's top left corner. If you want to use e.Location to get the screen coordinates, then you have to first do pictureBoxSnap.PointToScreen(Point.Empty); and then offset by the e.Location.
Also, Cursor.Position returns a Point object, so making a new Point(...) is pointless.

I must add, if you are dealing with images, and you need to interact with mouse, and do any task related with offset, scroll, etc, I recommend you that library, it is open source and have a lot of examples and methods that will help you
https://github.com/cyotek/Cyotek.Windows.Forms.ImageBox

How to get mouse position on screen in WPF?

It works within a specific control, but it doesn't work out the specific control.
How to get mouse position and use mouse events independently of any control just directly from screen (without Platform Invoke)?
2 needed points:
Mouse events when mouse is not within a control, but on a screen.
Mouse position when mouse is not within a control, but on a screen.
It should be solved without using Platform Invoke.
Next two don't work:
System.Windows.Input.Mouse.GetPosition(this)
Doesn't get mouse position out a specific control.
System.Windows.Forms.Cursor.Position.X
System.Windows.Forms.Cursor.Position doesn't work because it has no types in a WPF app, but it works in a Windows Forms app.
IntelliSense gets System.Windows.Forms.Cursor.Position, but it doesn't get any type of Position, hence I can't get:
Position.X
Position.Y
and
Point pointToWindow = Mouse.GetPosition(this);
Point pointToScreen = PointToScreen(pointToWindow);
Doesn't get mouse position out a specific control.

Using MouseDown event of a control you can try this:
var point = e.GetPosition(this.YourControl);
EDIT:
You can capture mouse event to a specific control using Mouse.Capture(YourControl); so it will capture the mouse events even if it is not on that control. Here is the link

You can use PointToScreen
Converts a Point that represents the current coordinate system of the
Visual into a Point in screen coordinates.
Something like this:
private void MouseCordinateMethod(object sender, MouseEventArgs e)
{
var relativePosition = e.GetPosition(this);
var point= PointToScreen(relativePosition);
_x.HorizontalOffset = point.X;
_x.VerticalOffset = point.Y;
}
Do note that Mouse.GetPosition returns a Point, and PointToScreen converts the point to the screen coordinate
EDIT:
You can use the Mouse.Capture(SepcificControl);. From MSDN
Captures mouse input to the specified element.

I have little new found,
Code is below, fisrt build and run the Window ,
then just wheel your mouse one time on the window to invoke the endless screen detect of the Mouse Position.
(Thus I didn't find the way to detect mouse event out of the control in the second point of the question, but similar use an endless thread.)
But I just use a little skill to enable Windows.Forms in WPF Project, by simply use the Forms code in pure method, then refer that method in the Event Code Block.
.
Here's the Code:
Add two references to project:
System.Drawing
System.Windows.Forms
Xaml part:
<Window x:Class="Test.MainWindow"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:g="clr-namespace:Gma.UserActivityMonitor;assembly=Gma.UserActivityMonitor"
Title="MainWindow" Height="350" Width="525"
MouseWheel="MainWindow_OnMouseWheel">
<Grid>
<TextBlock Name="TBK" />
</Grid>
</Window>
Class Code:
public partial class MainWindow : Window
{
public MainWindow()
{
InitializeComponent();
}
public void KeepReportMousePos()
{
//Endless Report Mouse position
Task.Factory.StartNew(() =>
{
while(true){
this.Dispatcher.Invoke(
DispatcherPriority.SystemIdle,
new Action(() =>
{
GetCursorPos();
}));
}
});
}
public void GetCursorPos()
{
//get the mouse position and show on the TextBlock
System.Drawing.Point p = System.Windows.Forms.Cursor.Position;
TBK.Text = p.X + " " + p.Y;
}
private void MainWindow_OnMouseWheel(object sender, MouseWheelEventArgs e)
{
//invoke mouse position detect when wheel the mouse
KeepReportMousePos();
}
}

Why complicate things? Just pass null to get screen coordinates:
private void MouseCordinateMethod(object sender, MouseEventArgs e)
{
var screenPos = e.GetPosition(null);
// ...
}

How to create HotSpot in C# with PictureBox?

I am a new C# developer and I want to create a hotspot in an image that I put in my winform application. I followed the solution posted HERE, but I did not know where I should put the coordinates to make this method works:
protected override void OnMouseMove(MouseEventArgs mouseEvent)
{
string X = mouseEvent.X.ToString();
string Y = mouseEvent.Y.ToString();
}
Where should I put the coordinates? I have two coordinates (X,Y): 110, 45

Hotspot I feel should be a small rectangular area rather than just a coordinate. Suppose you want it to be a small square area of width 20 then you would write something like this:
EDIT:
Suppose you have a PictureBox on your form called PictureBox1 and you want that a small rectangle of say 20x20 size starting from Top-Left corner of the picturebox become a hotspot (i.e. when you take mouse over it you would see a HAND cursor) then on the MouSeMove event of the PictureBox write this:
private void pictureBox1_MouseMove(object sender, MouseEventArgs e)
{
if (e.X > 0 && e.X < 20 && e.Y > 0 && e.Y < 20)
this.Cursor = Cursors.Hand;
else
this.Cursor = Cursors.Default;
}
Please remember, we are just showing the Hand Cursor to denote a hotspot we have not yet handled a Click for that matter, to make it really a web kind hotspot. If you want to do something on Click, try using the MouseUp event, in the MouseUp event the same IF clause as above would give you the condition that user has clicked on the hotspot region.