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Get MouseWheel Scroll Position in a FlowLayoutPanel

I have a FlowLayoutPanel which can be scrolled by the user on the verticle axis. i have the following event handler which is used to see where the user has scrolled to and provides the position number within blocks of 405px:
private void ChangedParentFlowPanel_Scroll(object sender, ScrollEventArgs e)
{
int NewPos = e.NewValue;
int range = (NewPos - 1) / 405 + 1;
CurrentIndex_Changed = range;
tCounter.Text = CurrentIndex_Changed.ToString();
}
That works just fine and does exactly what i need when the user scrolls using the verticle bar. The problem i have is i need to update tCounter with the same value but this time when the user scrolls using the mouse wheel. I'Ve tried the following but this only ever seems to provide the Y axis value for the location of the mouse when it scrolls and not the location of the scroll itself:
private void ChangedParentFlowPanel_Wheel(object sender, MouseEventArgs e)
{
int NewPos = e.Location.Y;
MessageBox.Show(NewPos.ToString());
int range = (NewPos - 1) / 405 + 1;
CurrentIndex_Changed = range;
tCounter.Text = CurrentIndex_Changed.ToString();
}
The question is...how can i get the scroll position of the scroll in ChangedParentFlowPanel when a mousewheel is used?

Thanks to the comment by Hans Pasant here's the answer:
private void ChangedParentFlowPanel_Wheel(object sender, MouseEventArgs e)
{
int NewPos = Math.Abs(ChangedParentFlowPanel.AutoScrollPosition.Y);
int range = (NewPos - 1) / 405 + 1;
CurrentIndex_Changed = range;
tCounter.Text = CurrentIndex_Changed.ToString();
}
Math.Abs because the returned scroll Y value is minus and i need a positive value.

Panning Image in pictureBox not working

I have developed windows application in c# where I have a pictureBox inside a panel. I have applied zoom in and zoom out functionality in it. Now I want the image inside the pictureBox to pan. I have applied mouseDown, mouseMove and mouseUp event on pictureBox. The code for it is:
private void pictureBox2_MouseDown(object sender, MouseEventArgs e)
{
if (pflag == 1)
{
dragging = true;
start = e.Location;
}
}
private void pictureBox2_MouseMove(object sender, MouseEventArgs e)
{
// panning code
if (pflag == 1)
{
if (dragging && zoom == 1)
{
pictureBox2.Location = new Point(pictureBox2.Left + (e.Location.X - start.X), pictureBox2.Top + (e.Location.Y - start.Y));
}
}
}
private void pictureBox2_MouseUp(object sender, MouseEventArgs e)
{
if (pflag == 1)
{
dragging = false;
}
}
Here the image is panning but with no boundary control. Sometimes even the image goes below the panel area while panning. What I need here is, image should move top, left , right, bottom according to zoom factor i.e like how scroll bar works and not beyond that.

You don't need to worry about zoom as the mouse coordinates will be fine as they are. The distance of the shown pixels should be the same as those the cursor is moving..
You also do not really need the dragging variable, unless you use it for something else.
However you do need to check the mouse button during the MouseMove:
if (pflag == 1 && e.Button == System.Windows.Forms.MouseButtons.Left )
Do note few things:
The user expects that the spot he drags stays with the mouse cursor just as the pixel he touches should always move with the fingertip. Do not surprise him by scaling in the zoom-factor!
If you wanted to do that you would need to use a factor, not adding an number.
Yes, the scrollbars will factor in the zoom but also the lift will still stay with the mouse!
Here is an example of how to set limits to prevent the user from going too far. It it a little involved because it needs to work when zoomed in or out. Do not start with illegal positions, though, nor get into those while zooming!
// panning code
if ( pflag == 1 && e.Button == System.Windows.Forms.MouseButtons.Left )
{
{
Rectangle panRect = new Rectangle(panel1.Location, panel1.ClientSize);
Rectangle picRect = new Rectangle(pictureBox2.Location, pictureBox2.ClientSize);
int newLeft = pictureBox2.Left + (e.Location.X - start.X);
int newTop = pictureBox2.Top + (e.Location.Y - start.Y);
int newRight = newLeft + picRect.Width;
int newBottom = newTop + picRect.Height;
if ((newLeft < 0 && newRight < panRect.Width)
|| (newLeft > 0 /*&& newRight > panRect.Width */)) newLeft = picRect.Left;
if ((newTop < 0 && newBottom < panRect.Width)
|| (newTop > 0 /*&& newBottom > panRect.Height*/)) newTop = picRect.Top;
pictureBox2.Location = new Point(newLeft, newTop);
}
Text = "" + pictureBox2.Location;
}
Note the two parts I have commented out! As it is you can't move a picture that is smaller than the viewport; you can allow it by removing the comments but should then take care when zooming in to move it up and left to zero as it should never sit in the positve range and also overlap or else the scrollbars will behave in a weird way..!

Issues with hand Clapping gesture

This my code for clapping hand gesture ,i use the result to set a robotic arm end effector to a 3d location for every clap)
i want the event handler to trigger just once for every clap gesture,
and reset for another clap gesture. but when i clap and my hands are close together, my event handler keeps firing!! please how do i correct this issue. could i use a reset method or something
[hand clap code]
float previousDistance = 0.0f;
private void MatchClappingGesture(Skeleton skeleton)
{
if (skeleton == null)
{
return;
}
if (skeleton.Joints[JointType.WristRight].TrackingState == JointTrackingState.Tracked && skeleton.Joints[JointType.WristLeft].TrackingState == JointTrackingState.Tracked)
{
float currentDistance = GetJointDistance(skeleton.Joints[JointType.WristRight], skeleton.Joints[JointType.WristLeft]);
{
if (currentDistance < 0.1f && previousDistance > 0.1f )
{
if (this.GestureRecognized != null)
{
this.GestureRecognized(this, new GestureEventArgs(RecognitionResult.Success));
previousDate = DateTime.Now;
}
}
previousDistance = currentDistance;
}
}
}
this is where i call the event handler
private void Window_Loaded(object sender, RoutedEventArgs e)
{
try
{
kinect = KinectSensor.KinectSensors[0];
kinect.Start();
}
catch (Exception ex)
{
System.Windows.MessageBox.Show("Could not find Kinect Camera: " + ex.Message);
}
kinect.DepthStream.Enable(DepthImageFormat.Resolution640x480Fps30);
kinect.ColorStream.Enable(ColorImageFormat.RgbResolution1280x960Fps12);
kinect.SkeletonStream.Enable(new TransformSmoothParameters()
{
Correction = 0.5f,
JitterRadius = 0.05f,
MaxDeviationRadius = 0.05f,
Prediction = 0.5f,
Smoothing = 0.5f
});
kinect.AllFramesReady += Kinect_SkeletonAllFramesReady;
recognitionEngine = new GestureRecognitionEngine();
armEngine = new ArmControllerEngine();
recognitionEngine.GestureRecognized += new EventHandler<GestureEventArgs>(recognitionEngine_GestureRecognized);
}
event handler fires here
void recognitionEngine_GestureRecognized(object sender,
GestureEventArgs e)
{
//armEngine.setArm(raMove,port,servoId);
MessageBox.Show("HI");
}
the message box prints multiple time instead of just once!!please help

You must bear in mind that Kinect's measurements have a degree of inaccuracy. Also, in certain cases (like when the hands are together!!) that inaccuracy increases greatly, and the detected joint positions start jumping all over the place. Try it with the SDK's provided skeleton viewer and you'll see. This is often mitigated by using smoothing algorithms, but in your case that might not be the most adequate solution. Try increasing the distance you are using to detect the gesture, give it some 20cm or so (btw, what does your GetJointDistance returns? Meters? Then give it 0.2)

void wait(int a)
{
for (int i = 0; i < a; i++) ;
}
int count = 0;
void recognitionEngine_GestureRecognized(object sender, GestureEventArgs e)
{
wait(3);
clapShow();
}
//clap method
void clapShow()
{
count += 1;
if (count == 1)
{
MessageBox.Show("Gesture Capture Within >> " + time.Millisecond.ToString() + " milli Seconds");
}
count = 0 ;
}
}
I called the message box as a method every 3millsecs wait(3) so that slows down the the event handler.
Then set the count to "1" before a gesture then back to "0"after every clap gesture and it works pretty well!!
Note!.... The wait(X) method i created a simple loop that counts down to the value X. It can be any value based on the level of sensitivity level one desires. Thanks jose!!
i hope this helps someone..

Moving Picturebox on a Grid is inaccurate because Mouse Positions are inaccurate

I have an Application where I put Pictureboxes on a Panel. After I successfully implemented Drag&Drop for the Pictureboxes, I wanted to add a Grid option to conviniently move the Pictureboxes on the Panel. The code I used is
private void PB14_MouseMove(object sender, MouseEventArgs e)
{
if (e.Button == MouseButtons.Left)
{
if (grid)
{
if (MousePosition.X % 10 == 0)
{
PBList[14].Location = new Point(PList[parent].PointToClient(new Point(MousePosition.X, MousePosition.Y)).X, PBList[14].Location.Y);
}
if (MousePosition.Y % 10 == 0)
{
PBList[14].Location = new Point(PBList[14].Location.X, PList[parent].PointToClient(new Point(MousePosition.X, MousePosition.Y)).Y);
}
}
else
{
...
}
}
}
PList is a List of Panels, PList[parent] is the parent in which the picturebox (out of a Pictureboxlist) PBList[14] is.
The Problem is that the Picturebox is not smoothely moving, sometimes it doesnt move at all. I found out that some values for the % operation are better some are worse, for example if I put
if (MousePosition.X % 30 == 0)
in the if statement, it is worse than 10.
I put the values of the if() in labels and i saw that it would sometimes skip the calculation, means the value jumped from 9 to 1, skipping the pixel where it should be 0 and the Picturebox didnt move.
Do you know any better ways of calculating the mouse coordinates for this purpose?

You'll want to determine the closest pixel of the grid pixels to your mouse position.
PBList[14].Location = new Point(PList[parent].PointToClient(new Point(MousePosition.X - (MousePosition.X % 10) + 5, MousePosition.Y - (MousePosition.Y % 10) + 5)).X);
Although my confusion is setting in here about the required parameters for PointToClient.
The jist of it is, recalculate the position for each mouse move regardless of whether it is directly on your 'grid by 10s', assign the location if it is different from the last (to save resources on re-painting) and find the closest 'grid by 10s' position by subracting the co-ords remainder of 10 from the co-ord

The problem is you only move anything when the mouse is exactly over one of the grid points.
One way to do this is allowing an extra pixel on each side:
if ((MousePosition.X+1) % 30 < 3)
{
int newX = MousePosition.X + 1 - ((MousePosition.X+1) % 30);
PBList[14].Location = new Point(PList[parent].PointToClient(new Point(newX, MousePosition.Y)).X, PBList[14].Location.Y);
}
//Same for Y

I was able to add snap-to-grid behaviour to my typical drag-and-drop implementation. The grid is based on the Control's Height and Width. You can change this by replacing control.Height and control.Width with constants, if you prefer. You may also want to prevent the Control from being dragged off screen.
private void OnMouseMove(object sender, MouseEventArgs e)
{
if (e.Button == MouseButtons.Left)
{
control.Left = ((e.X + control.Left) / control.Width) * control.Width;
control.Top = ((e.Y + control.Top) / control.Height) * control.Height;
}
}
If you want the Control to drag smoothly and only snap-to-grid when you release the mouse button instead:
private void OnMouseMove(object sender, MouseEventArgs e)
{
if (e.Button == MouseButtons.Left)
{
control.Left += e.X - offset.X;
control.Top += e.Y - offset.Y;
}
}
private void OnMouseUp(object sender, MouseEventArgs e)
{
control.Left = ((control.Left + control.Width / 2) / control.Width) * control.Width;
control.Top = ((control.Top + control.Height / 2) / control.Height) * control.Height;
}
private void OnMouseDown(object sender, MouseEventArgs e)
{
offset = e.Location;
}

winform move an image inside a picturebox

I've been trying to do this for a few hours now, but for the life of me I can't make it possible.
What I'm trying to do is simply move the image found within a picture box in a winform application. My image is roughly 1000x1000 pixels and my box is something arbitrary like 400x500, so, for example, when I click the mouse I'd want the image to move 50 to the left. But the image box should remain the same size.
For the life of me, however, I can't get this to work. What I have been able to do is the following:
if (kinectController.hands[0].fingertips.Count == 1)
{
pictureBox1.SizeMode = PictureBoxSizeMode.CenterImage;
}
This function is for my kinect finger tracking app. So when the application finds a single finder point visiable on the screen, the image is centered. However, I would eventually like the image to move along with my finger movement, which will come once I work out the basic step of moving the image a few pixels to the side.
Any help with this would be appreciated.

I did a little bit of research and apparently moving an image within a PictureBox is no easy task, at the very least I couldn't find anything that would make this possible (not saying there isn't a way to do it though).
However, I came up with a bit of a "workaround", see if this fits your needs. To accomplish this:
Create a Panel control, and size it to however much of the image you
would like to display
Inside that panel place a PictureBox control with your image in it
and set the SizeMode property to AutoSize.
Now, put this code in your form
private bool Dragging;
private int xPos;
private int yPos;
private void pictureBox1_MouseUp(object sender, MouseEventArgs e) { Dragging = false; }
private void pictureBox1_MouseDown(object sender, MouseEventArgs e) {
if (e.Button == MouseButtons.Left) {
Dragging = true;
xPos = e.X;
yPos = e.Y;
}
}
private void pictureBox1_MouseMove(object sender, MouseEventArgs e) {
Control c = sender as Control;
if (Dragging && c!= null) {
c.Top = e.Y + c.Top - yPos;
c.Left = e.X + c.Left - xPos;
}
}
Now whenever you click and drag on the PictureBox, it won't actually move the image within it, but the PictureBox control within the panel. Again, not exactly what you were looking for and I'm not sure how this would convert over to Kinect, but I hope this gets you on the right track.

Not enough reputation to comment but I wanted to add on Ben Black answer if someone ever need more control over the image moving around so you can't move the image past it's borders :
private void pictureBox1_MouseMove(object sender, MouseEventArgs e)
{
Control c = sender as Control;
if (Dragging && c != null)
{
int maxX = pictureBox1.Size.Width * -1 + panel.Size.Width;
int maxY = pictureBox1.Size.Height * -1 + panel.Size.Height;
int newposLeft = e.X + c.Left - xPos;
int newposTop = e.Y + c.Top - yPos;
if (newposTop > 0)
{
newposTop = 0;
}
if (newposLeft > 0)
{
newposLeft = 0;
}
if (newposLeft < maxX)
{
newposLeft = maxX;
}
if (newposTop < maxY)
{
newposTop = maxY;
}
c.Top = newposTop;
c.Left = newposLeft;
}
}