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C# Application to Zoom in/out the image in a PictureBox

I am somewhat new to programming in general, but I am eager to learn more and I was wondering if anyone could possibly help me out with an idea.
(main goal)
I want to make a simple program that consists of a C# Windows Forms Application that displays a preset image (of 6000x6000 pixel dimensions, SizeMode set to Zoom so the entire image is visible on the form at once) in a PictureBox that will take up the entire form practically, save for a space at the bottom of the form where I want to display a TrackBar that will allow you to zoom the image in and out; as well as a horizontal scroll bar at the base of the PictureBox, and a vertical scroll bar on the right side of the PictureBox to scroll around the map when it is zoomed, and I wanted to be able to control these scroll bars by either clicking and dragging in a corresponding direction on the PictureBox (preferred but not sure if its possible) or by using the scroll wheel on the mouse (probably easier but once again not sure).
(reference)
[ Here is my form completed exactly as I described, with a 6000x6000 placement holder demo texture in a PictureBox using SizeMode Zoom, as an example - THIS HAS BEEN HANDLED, NEXT PART OF THE PROBLEM IS UPDATED BELOW:]
(addendum)
The only issue I am having is the code, as I am pretty much greenhorn in that department. I have been working to learn Visual Studio's workflow, but I really could use some help.
Thank you so much in advance for anything you can help me with.
UPDATE:
After doing research on the subject and taking time to do some thinking, I have come up with the code listed below; but my problem is that when I pan my image too far, the image is allowed to be pulled too far over, thus exposing the panel behind it when the image is panned/pulled too far over to one corner. Also, when I zoom too far out, the image is allowed to become WAY smaller than the Picturebox.
Panning issue, the grey parts of the panel are the problem
Zoom issue, the grey parts of the panel are the problem
So, my last question: How would I go about revising the code below to 'lock' the image that I am panning and zooming from being allowed to pan or zoom outside of its frame and expose the panel behind it?
public partial class ImageZoomMainForm : Form
{
Image img;
Point mouseDown;
int startx = 0;
int starty = 0;
int imgx = 0;
int imgy = 0;
bool mousepressed = false;
float zoom = 1;
public ImageZoomMainForm()
{
InitializeComponent();
string imagefilename = #"..\..\ViewPort_MAIN.tif";
img = Image.FromFile(imagefilename);
Graphics g = this.CreateGraphics();
zoom = ((float)pictureBox.Width / (float)img.Width) * (img.HorizontalResolution / g.DpiX);
pictureBox.Paint += new PaintEventHandler(imageBox_Paint);
}
private void pictureBox_MouseMove(object sender, EventArgs e)
{
MouseEventArgs mouse = e as MouseEventArgs;
if (mouse.Button == MouseButtons.Left)
{
Point mousePosNow = mouse.Location;
int deltaX = mousePosNow.X - mouseDown.X;
int deltaY = mousePosNow.Y - mouseDown.Y;
imgx = (int)(startx + (deltaX / zoom));
imgy = (int)(starty + (deltaY / zoom));
pictureBox.Refresh();
}
}
private void imageBox_MouseDown(object sender, EventArgs e)
{
MouseEventArgs mouse = e as MouseEventArgs;
if (mouse.Button == MouseButtons.Left)
{
if (!mousepressed)
{
mousepressed = true;
mouseDown = mouse.Location;
startx = imgx;
starty = imgy;
}
}
}
private void imageBox_MouseUp(object sender, EventArgs e)
{
mousepressed = false;
}
protected override void OnMouseWheel(MouseEventArgs e)
{
float oldzoom = zoom;
if (e.Delta > 0)
{
zoom += 0.1F;
}
else if (e.Delta < 0)
{
zoom = Math.Max(zoom - 0.1F, 0.01F);
}
MouseEventArgs mouse = e as MouseEventArgs;
Point mousePosNow = mouse.Location;
int x = mousePosNow.X - pictureBox.Location.X;
int y = mousePosNow.Y - pictureBox.Location.Y;
int oldimagex = (int)(x / oldzoom);
int oldimagey = (int)(y / oldzoom);
int newimagex = (int)(x / zoom);
int newimagey = (int)(y / zoom);
imgx = newimagex - oldimagex + imgx;
imgy = newimagey - oldimagey + imgy;
pictureBox.Refresh();
}
private void imageBox_Paint(object sender, PaintEventArgs e)
{
e.Graphics.InterpolationMode = InterpolationMode.HighQualityBicubic;
e.Graphics.ScaleTransform(zoom, zoom);
e.Graphics.DrawImage(img, imgx, imgy);
}
protected override bool ProcessCmdKey(ref Message msg, Keys keyData)
{
const int WM_KEYDOWN = 0x100;
const int WM_SYSKEYDOWN = 0x104;
if ((msg.Msg == WM_KEYDOWN) || (msg.Msg == WM_SYSKEYDOWN))
{
switch (keyData)
{
case Keys.Right:
imgx -= (int)(pictureBox.Width * 0.1F / zoom);
pictureBox.Refresh();
break;
case Keys.Left:
imgx += (int)(pictureBox.Width * 0.1F / zoom);
pictureBox.Refresh();
break;
case Keys.Down:
imgy -= (int)(pictureBox.Height * 0.1F / zoom);
pictureBox.Refresh();
break;
case Keys.Up:
imgy += (int)(pictureBox.Height * 0.1F / zoom);
pictureBox.Refresh();
break;
case Keys.PageDown:
imgy -= (int)(pictureBox.Height * 0.90F / zoom);
pictureBox.Refresh();
break;
case Keys.PageUp:
imgy += (int)(pictureBox.Height * 0.90F / zoom);
pictureBox.Refresh();
break;
}
}
return base.ProcessCmdKey(ref msg, keyData);
}
private void ImageZoomMainForm_Load(object sender, EventArgs e)
{
}
}
}

A picturebox inside a Panel,
the panel should be set its AutoSroll to True,
the picturebox with SizeMode to Zoom
the trackbar change can increase and decrease the size of inside picturebox so that the outer panel will have auto scroll
dragging also possible using several mouse events of the picturebox.

Detect mouse movement if Cursor is locked

I am developing Cad application and want to implement snap - when user moves mouse near some object, I set Cursor.Position to the center point of that object. If user moves mouse say 7 pixels in any direction, then Cursor is set free.The way I do it is - I store snaped Cursor position and then under MouseMoveEvent I calculate the distance from stored position to current position. If this position is smaller than defined threshold then I set current cursor position back to stored value. Every time MouseMoveEvent is called that small difference between two cursor positions is added to previously calclated difference, so sooner or later my threshold is reached and Cursor jumps out of snaped position. Code sample:
var x = Cursor.Position.X - storedPosition.X;
pixelsX += x;
int threshold = 7;
if (pixelsX > threshold)
{
Cursor.Position = new System.Drawing.Point(storedPosition.X + 10, storedPosition.Y);
snapReleased = true;
}
The problem with this is that in every MouseMoveEvent mouse is moved very small amount and if threshold is not reached it is set back to stored position which makes Cursor blink(which is very annoying) So my question is - is there a way to detect mouse movement if Cursor is locked in one position?

I would not "snap" the mouse pointer. Do you know the feeling when your mouse is stuck? Depending on your age you may remember roller mice, those with a rubber ball inside. It is horrible.
Instead, I think that the objects you are about to select or are currently moving should react with a snap. For example, when you are about to select an object, when the mouse pointer is closer than the threshold the object gets highlighted. The user can the click the mouse and grab the object.
When moving an object, the object can snap into place when closer than the threshold to another object, guide lines, etc.

The following is a custom panel control that demonstrates an owner drawn cursor that snaps to a grid (snapPoints). The system cursor is hidden/shown on mouse entry/leave. The snap to point distance is controlled by the constant snapLimit.
using System;
using System.Collections.Generic;
using System.Windows.Forms;
using System.Drawing;
namespace WindowsFormsApplication1
{
public class DrawingSurface : Panel
{
private const double snapLimit = 7.0D;
private List<Point> snapPoints = new List<Point>();
private Point cursorPos;
private Point lastDrawnPos;
private bool drawCursor;
public DrawingSurface() : base()
{
this.BorderStyle = BorderStyle.Fixed3D;
this.BackColor = Color.AliceBlue;
this.DoubleBuffered = true;
this.Cursor = Cursors.Cross;
}
protected override void OnMouseEnter(EventArgs e)
{
base.OnMouseEnter(e);
System.Windows.Forms.Cursor.Hide();
}
protected override void OnMouseLeave(EventArgs e)
{
base.OnMouseLeave(e);
System.Windows.Forms.Cursor.Show();
this.drawCursor = false;
this.Invalidate();
}
protected override void OnPaint(PaintEventArgs e)
{
base.OnPaint(e);
foreach (Point dot in this.snapPoints)
{
e.Graphics.FillEllipse(Brushes.Red, dot.X - 1, dot.Y - 1, 2, 2);
}
if (drawCursor)
{
Cursor cur = System.Windows.Forms.Cursor.Current;
Point pt = this.cursorPos;
pt.Offset(-cur.HotSpot.X, -cur.HotSpot.Y);
Rectangle target = new Rectangle(pt, cur.Size);
cur.Draw(e.Graphics, target);
this.lastDrawnPos = this.cursorPos;
}
}
protected override void OnMouseMove(MouseEventArgs e)
{
base.OnMouseMove(e);
SetCursor(e.Location);
}
private void SetCursor(Point loc)
{
this.cursorPos = loc;
foreach (Point pt in this.snapPoints)
{
double deltaX = loc.X - pt.X;
double deltaY = loc.Y - pt.Y;
double radius = Math.Sqrt((deltaX * deltaX) + (deltaY * deltaY));
if (radius < snapLimit)
{
this.cursorPos = pt;
break;
}
}
if (lastDrawnPos != this.cursorPos)
{
this.drawCursor = true;
this.Invalidate();
}
}
protected override void OnSizeChanged(EventArgs e)
{
base.OnSizeChanged(e);
this.snapPoints.Clear();
for (int y = 0; y <= this.ClientRectangle.Height; y += 50)
{
for (int x = 0; x <= this.ClientRectangle.Width; x += 50)
{
this.snapPoints.Add(new Point(x, y));
}
}
}
}
}

Making a object bounce

I am trying to make a elipse bounce on a rectangle. I am using a timer to move the elipse in both x and y-direction. My idea was to create an if statement to see if the coordinates of the elipse matches the coordinates of the rectangle.
Here is the code I had written so far:
public partial class Form1 : Form
{
Class1 square = new Class1();
public int before;
public int after;
public int c;
public Form1()
{
InitializeComponent();
}
protected override void OnPaint(PaintEventArgs e)
{
after = 590 - (b * b) / 100;
before = 100 + (a * a) / 100;
c = a + b;
Graphics g = e.Graphics;
SolidBrush Brush = new SolidBrush(Color.White);
g.FillEllipse(Brush, a, before, 10, 10);
square.Draw(g);
if (k >= square.y && a >= square.x && a <= square.x + 40)
{
a=c;
before= after;
timer1.Start();
timer2.Stop();
}
else if (k >= square.y + 10)
{
timer2.Stop();
MessageBox.Show("You lost");
}
}
protected override void OnMouseMove(MouseEventArgs e)
{
base.OnMouseMove(e);
square.x = e.X;
Cursor.Hide();
}
public int a = 0;
public int b = 0;
public void timer2_Tick(object sender, EventArgs e)
{
a += 1;
Invalidate();
}
private void timer1_Tick(object sender, EventArgs e)
{
b += 1;
Invalidate();
}
}
I know that there are problems. And I have some questions:
Is there a easier way to make the elipse " bounce"?
Is the problem solely with the maths of the curve that the elipse is following?
I know the question may be somewhat undefined or abstract but any help is appriciated. And if you want me to be clearer in some ways, let me know! Thanks

A simple way to make the ellipse bounce of the edges is to check its edge points against the bounds, and then just invert the proper direction. So, something like this should work, if you'll pardon the pseudo-code
loop used to animate the ellipse
before moving, check the position:
if right-most position == right wall
invert x velocity
if left-most position == left wall
invert x velocity
if top-most position == top wall
invert y velocity
if bottom-most position == bottom wall
invert y velocity
move ellipse to next position
This is a pretty simple simulation, but it should give you an idea of how to progress and develop a more sophisticated model. Hope this helps!

2D parallaxing background on both X and Y axis using XNA and C#

I am working on a space shooter game using XNA and have followed multiple tutorials to create a parallax background. So far I can get it to go along one axis, either X or Y, but not both at the same time. I have a camera class that follows the player, which the player moves (instead of the 'world'), since I figured it would be easier to just move the player versus moving everything else around the player.
So far, the background doesn't keep up with the player, and it also can't comprehend both axis at the same time. I thought about a tile engine, but that wouldn't let me parallax different layers would it?
Could anyone help me understand what I need to do, or recommend a tutorial that can do both axis at the same time? I can't seem to find the answer on my own this time.
Here is the code for my background class:
class Background
{
// Textures to hold the two background images
Texture2D spaceBackground, starsParallax;
int backgroundWidth = 2048;
int backgroundHeight = 2048;
int parallaxWidth = 2048;
int parallaxHeight = 2048;
int backgroundWidthOffset;
int backgroundHeightOffset;
int parallaxWidthOffset;
int parallaxHeightOffset;
public int BackgroundWidthOffset
{
get { return backgroundWidthOffset; }
set
{
backgroundWidthOffset = value;
if (backgroundWidthOffset < 0)
{
backgroundWidthOffset += backgroundWidth;
}
if (backgroundWidthOffset > backgroundWidth)
{
backgroundWidthOffset -= backgroundWidth;
}
}
}
public int BackgroundHeightOffset
{
get { return backgroundHeightOffset; }
set
{
backgroundHeightOffset = value;
if (backgroundHeightOffset < 0)
{
backgroundHeightOffset += backgroundHeight;
}
if (backgroundHeightOffset > backgroundHeight)
{
backgroundHeightOffset -= backgroundHeight;
}
}
}
public int ParallaxWidthOffset
{
get { return parallaxWidthOffset; }
set
{
parallaxWidthOffset = value;
if (parallaxWidthOffset < 0)
{
parallaxWidthOffset += parallaxWidth;
}
if (parallaxWidthOffset > parallaxWidth)
{
parallaxWidthOffset -= parallaxWidth;
}
}
}
public int ParallaxHeightOffset
{
get { return parallaxHeightOffset; }
set
{
parallaxHeightOffset = value;
if (parallaxHeightOffset < 0)
{
parallaxHeightOffset += parallaxHeight;
}
if (parallaxHeightOffset > parallaxHeight)
{
parallaxHeightOffset -= parallaxHeight;
}
}
}
// Constructor when passed a Content Manager and two strings
public Background(ContentManager content,
string sBackground, string sParallax)
{
spaceBackground = content.Load<Texture2D>(sBackground);
backgroundWidth = spaceBackground.Width;
backgroundHeight = spaceBackground.Height;
starsParallax = content.Load<Texture2D>(sParallax);
parallaxWidth = starsParallax.Width;
parallaxHeight = starsParallax.Height;
}
public void Draw(SpriteBatch spriteBatch)
{
// Draw the background panel, offset by the player's location
spriteBatch.Draw(
spaceBackground,
new Rectangle(-1 * backgroundWidthOffset,
-1 * backgroundHeightOffset,
backgroundWidth,
backgroundHeight),
Color.White);
// If the right edge of the background panel will end
// within the bounds of the display, draw a second copy
// of the background at that location.
if (backgroundWidthOffset > backgroundWidth)
{
spriteBatch.Draw(
spaceBackground,
new Rectangle(
(-1 * backgroundWidthOffset) + backgroundWidth, 0,
backgroundWidth, backgroundHeight),
Color.White);
}
else //(backgroundHeightOffset > backgroundHeight - viewportHeight)
{
spriteBatch.Draw(
spaceBackground,
new Rectangle(
0, (-1 * backgroundHeightOffset) + backgroundHeight,
backgroundHeight, backgroundHeight),
Color.White);
}
// Draw the parallax star field
spriteBatch.Draw(
starsParallax,
new Rectangle(-1 * parallaxWidthOffset,
0, parallaxWidth,
parallaxHeight),
Color.SlateGray);
// if the player is past the point where the star
// field will end on the active screen we need
// to draw a second copy of it to cover the
// remaining screen area.
if (parallaxWidthOffset > parallaxWidth)
{
spriteBatch.Draw(
starsParallax,
new Rectangle(
(-1 * parallaxWidthOffset) + parallaxWidth,
0,
parallaxWidth,
parallaxHeight),
Color.White);
}
}
}
The main game then has ties to move the backgrounds, along with the player.
background.BackgroundWidthOffset -= 2;
background.ParallaxWidthOffset -= 1;
Visually, the background is sort of jumpy, and seems to randomly skip or overlap background tiles.

I've used this method in the past with great results:
http://www.david-gouveia.com/scrolling-textures-with-zoom-and-rotation/
It uses a shader to accomplish the effect, resulting in a fast implementation.

There is a complete example here.

Form position on lower right corner of the screen

I am using c# WinForm to develop a sman notification app. I would like to place the main form on the lower right corner of the screen working area.
In case of multiple screens, there is a way to find the rightmost screen where to place the app, or at least remember the last used screen and palce the form on its lower right corner?

I don't currently have multiple displays to check, but it should be something like
public partial class LowerRightForm : Form
{
public LowerRightForm()
{
InitializeComponent();
}
protected override void OnLoad(EventArgs e)
{
PlaceLowerRight();
base.OnLoad(e);
}
private void PlaceLowerRight()
{
//Determine "rightmost" screen
Screen rightmost = Screen.AllScreens[0];
foreach (Screen screen in Screen.AllScreens)
{
if (screen.WorkingArea.Right > rightmost.WorkingArea.Right)
rightmost = screen;
}
this.Left = rightmost.WorkingArea.Right - this.Width;
this.Top = rightmost.WorkingArea.Bottom - this.Height;
}
}

Override the Form Onload and set the new location :
protected override void OnLoad(EventArgs e)
{
var screen = Screen.FromPoint(this.Location);
this.Location = new Point(screen.WorkingArea.Right - this.Width, screen.WorkingArea.Bottom - this.Height);
base.OnLoad(e);
}

//Get screen resolution
Rectangle res = Screen.PrimaryScreen.Bounds;
// Calculate location (etc. 1366 Width - form size...)
this.Location = new Point(res.Width - Size.Width, res.Height - Size.Height);

This following code should work :)
var rec = Screen.PrimaryScreen.WorkingArea;
int margain = 10;
this.Location = new Point(rec.Width - (this.Width + margain), rec.Height - (this.Height + margain));

int x = Screen.PrimaryScreen.WorkingArea.Right - this.Width;
int y = Screen.PrimaryScreen.WorkingArea.Bottom - this.Height;
// Add this for the real edge of the screen:
x = 0; // for Left Border or Get the screen Dimension to set it on the Right
this.Location = new Point(x, y);