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How to make a shape move with the arrow keys?

using System.Drawing;
using System.Windows.Forms;
public partial class Form1 : Form
{
int vx = 5;
int vy = 5;
int bx = 0;
int by = 50;
int px = 93;
public Form1()
{
InitializeComponent();
timer1.Interval = 100;
timer1.Start();
}
public class Ball
{
public int X;
public int Y;
public int W;
public int H;
public Ball(int x, int y, int w, int h)
{
X = x;
Y = y;
W = w;
H = h;
}
}
public class Paddle
{
public int X;
public int Y;
public int W;
public int H;
public Paddle(int x, int y, int w, int h)
{
X = x;
Y = y;
W = w;
H = h;
}
}
public class Brick
{
public int X;
public int Y;
public int W;
public int H;
public Brick(int x, int y, int w, int h)
{
X = x;
Y = y;
W = w;
H = h;
}
}
private void Form1_Paint(object sender, PaintEventArgs e)
{
int[] brickxs = { 0, 51, 102, 153, 204, 255, 306, 357, 408, 459, 510, 561, 612, 663, 714, 765 };
int bc = 0;
SolidBrush blueBrush = new SolidBrush(Color.Blue);
Ball b = new Ball(55, 55, 25, 25);
Paddle p = new Paddle(93, 377, 130, 30);
Brick br = new Brick(20, 20, 51, 20);
br.X = 0;
while (bc < 16)
{
br.X = brickxs[bc];
System.Drawing.SolidBrush myBrush = new System.Drawing.SolidBrush(System.Drawing.Color.Red);
System.Drawing.Graphics formGraphics;
formGraphics = this.CreateGraphics();
formGraphics.FillRectangle(myBrush, new Rectangle(br.X, 0, 49, 20));
myBrush.Dispose();
formGraphics.Dispose();
bc = bc + 1;
}
Rectangle ball = new Rectangle(bx, by, b.W, b.H);
Rectangle paddle = new Rectangle(px, p.Y, p.W, p.H);
//Rectangle brick = new Rectangle(br.X, br.Y, br.W, br.H);
e.Graphics.FillEllipse(blueBrush, ball);
e.Graphics.FillRectangle(blueBrush, paddle);
//e.Graphics.FillRectangle(blueBrush, brick);
}
private void Form1_KeyDown(object sender, KeyEventArgs e)
{
if (e.KeyData == Keys.Right)
{
px += 5;
}
}
private void MoveTimer_Tick(object sender, EventArgs e)
{
Invalidate();
}
private void timer1_Tick(object sender, EventArgs e)
{
bx = bx + vx;
by = by + vy;
if (px <= 0)
{
px = 0;
}
if (px >= 771)
{
px = 771;
}
WallCollision();
floorandCeilingCollision();
Invalidate();
}
public void WallCollision()
{
if (bx >= 771)
{
vx = -5;
}
if (bx <= 0)
{
vx += 5;
}
}
public void floorandCeilingCollision()
{
if (by >= 420)
{
vy = -5;
}
if (by <= 0)
{
vy = 5;
}
}
}
I am creating a game and I need some help.
In my code have classes for each of the parts of the game: the ball, paddle and bricks. The array positions the bricks.
I want to move the paddle (which just a rectangle) left and right with the arrow keys. I tried to use the key down method but it did not work.
Could you suggest any solutions or point out anything that I left out?

Personally, I use e.KeyCode instead of e.KeyData, try this first.
Make sure your Form is focused, and not a picturebox or something else you might have in the game. Because you try to call the KeyDown event for your Form, not for a control inside your Form.
I never used a Paint event, are you sure it is called? It might be the case that your game registeres the movement but never shows the changes to you. I usually have a separate method for drawing and I call it every time there is a change, you should try this too.
If nothing works, try debugging. Set a break point in your KeyDown method to see if it is called. If it does, set it in the Paint method. This one will surely be called once, at runtime, but if you click "Continue" on that time and try to move your object. If it is not called any other time, then here is your answer :)
Please update me with what you find after trying this things, and ask me what to do next if you get stuck or simply don't know what else there is to do :)

select two point to Draw a circle

I am using visual studio c# windows form, I need help to draw a circle using the Mouse click.. first click will give me the center of the circle equal to the cursor position and the second click will give me a point on the border of the circle equal to the second position of the cursor, the distance between the to points will give me the radius..now I have radius and point ..I can draw a circle ..The code doesn't work because I only can get one position of the cursor no matter how many times I click the mouse
private void Form1_MouseDown(object sender, MouseEventArgs e)
{
int lastX = Cursor.Position.X;//the first click x cursor position
int lastY = Cursor.Position.Y;//the first click y cursor position,
//is there any way to reuse the Cursor.Position for different point ??
int x = Cursor.Position.X;//the second click x cursor position
int y = Cursor.Position.Y;//the second click y cursor position
Graphics g;
double oradius=Math.Sqrt(((lastX-x)^2) +((lastY-y)^2));
//double newy = Math.Sqrt(lastY);
// int newxv = Convert.ToInt32(newx);
int radius= Convert.ToInt32(oradius);
g = this.CreateGraphics();
Rectangle rectangle = new Rectangle();
PaintEventArgs arg = new PaintEventArgs(g, rectangle);
DrawCircle(arg, x, y,radius,radius);
}
private void DrawCircle(PaintEventArgs e, int x, int y, int width, int height)
{
System.Drawing.Pen pen = new System.Drawing.Pen(System.Drawing.Color.Red, 3);
e.Graphics.DrawEllipse(pen, x - width / 2, y - height / 2, width, height);
}
}

You need to store the first click as well before you start doing the calculations. One way to do this is to create a class that simply throws an event every second time you pass it x and y coordinates like this:
public class CircleDrawer
{
private int _firstX;
private int _firstY;
private int _secondX;
private int _secondY;
private bool _isSecondClick;
private event EventHandler OnSecondClick;
public void RegisterClick(int x, int y)
{
if(_isSecondClick)
{
_secondX = x;
_secondY = y;
if(OnSecondClick != null)
OnSecondClick(this, null);
}
else
{
_firstX = x;
_firstY = y;
_isSecondClick = true;
}
}
}
You can then in your code simply call your methods:
private void Form1_MouseDown(object sender, MouseEventArgs e)
{
int lastX = Cursor.Position.X;//the first click x cursor position
int lastY = Cursor.Position.Y;//the first click y cursor position,
_circleDrawer.RegisterClick(lastX, lastY);
}
And in your constuctor:
public MyForm()
{
_circleDrawer = new CircleDrawer();
_circleDrawer.OnSecondClick += DrawCircle();
}
public void DrawCircle()
{
// Your drawing code
}

Your lastX and lastY are local variables, and you initialize them in the beginning of the MouseDown event handler. They should be class level variables and should be populated at the end of the MouseDown event handler.
Also, you should test if they already have a value, and only if they have value then draw the circle and then clear them (so that the next circle will have it's own center).
Here is an improvement of your code. Note I've used the using keyword with the graphics object and with the pen - get used to use it every time you are using an instance of anything that's implementing the IDisposable interface.
private void Form1_MouseDown(object sender, MouseEventArgs e)
{
if (_lastPosition != Point.Empty)
{
var currentPosition = Cursor.Position;
var oradius = Math.Sqrt(((_lastPosition.X - currentPosition.X) ^ 2) + ((_lastPosition.Y - currentPosition.Y) ^ 2));
var radius = Convert.ToInt32(oradius);
using (var g = this.CreateGraphics())
{
var arg = new PaintEventArgs(g, new Rectangle());
DrawCircle(arg, currentPosition, radius, radius);
}
_lastPosition = Point.Empty;
}
else
{
_lastPosition = Cursor.Position;
}
}
private void DrawCircle(PaintEventArgs e, Point position, int width, int height)
{
using (var pen = new System.Drawing.Pen(System.Drawing.Color.Red, 3))
{
e.Graphics.DrawEllipse(pen, position.X - width / 2, position.Y - height / 2, width, height);
}
}
Note: This code can be improved even further.

There are many things fundamentally wrong with this code, here is a complete, working example.
public partial class Form1 : Form
{
public Form1()
{
InitializeComponent();
}
private Point clickCurrent = Point.Empty;
private Point clickPrev = Point.Empty;
private void Form1_MouseDown(object sender, MouseEventArgs e)
{
clickPrev = clickCurrent;
clickCurrent = this.PointToClient(Cursor.Position);
if (clickPrev == Point.Empty) return;
Graphics g;
double oradius = Math.Sqrt((Math.Pow(clickPrev.X - clickCurrent.X, 2)) + (Math.Pow(clickPrev.Y - clickCurrent.Y, 2)));
int radius = Convert.ToInt32(oradius);
g = this.CreateGraphics();
Rectangle rectangle = new Rectangle();
PaintEventArgs arg = new PaintEventArgs(g, rectangle);
DrawCircle(arg, clickPrev.X, clickPrev.Y, radius * 2, radius * 2);
clickCurrent = Point.Empty;
}
private void DrawCircle(PaintEventArgs e, int x, int y, int width, int height)
{
System.Drawing.Pen pen = new System.Drawing.Pen(System.Drawing.Color.Red, 3);
e.Graphics.DrawEllipse(pen, x - width / 2, y - height / 2, width, height);
}
}

private int _firstX;
private int _firstY;
private int _secondX;
private int _secondY;
private bool _isSecondClick;
private void Form1_MouseDown(object sender, MouseEventArgs e)
{
if (_isSecondClick)
{
_secondX = Cursor.Position.X;
_secondY = Cursor.Position.Y;
var radious1 = Math.Pow(_firstX - _secondX, 2);
var radious2 = Math.Pow(_firstY - _secondY, 2);
var radious = Math.Sqrt(radious1 + radious2);
Graphics g = this.CreateGraphics();
Rectangle rectangle = new Rectangle();
PaintEventArgs arg = new PaintEventArgs(g, rectangle);
DrawCircle(arg, _secondX, _secondY, radious, radious);
}
else
{
_firstX = Cursor.Position.X;
_firstY = Cursor.Position.Y;
_isSecondClick = true;
}
}
private void DrawCircle(PaintEventArgs arg, int x, int y, double width, double height)
{
System.Drawing.Pen pen = new System.Drawing.Pen(System.Drawing.Color.Red, 3);
var xL = Convert.ToInt32(x - width / 2);
var yL = Convert.ToInt32(y - height / 2);
var hL = Convert.ToInt32(height);
var wL = Convert.ToInt32(width);
arg.Graphics.DrawEllipse(pen, xL, yL, wL, hL);
}

Tool strip menu items not displaying

When my windows form loads the tool strip menu item bar is there but the items inside it are not shown until I hover over them or press alt.
Also, my colordialog box wont open until after I click the change color icon in my menu and then press Alt.
I've had a look through the properties to make sure there is no hide property on or something but I can't seem to find anything.
I've posted some links below to show you what's happening.
When it opens up: http://gyazo.com/c1f4fa4d27e3f54a65b1f8a3da6cd0da
When I press alt or hover over menu: http://gyazo.com/c86c5dfb723647c025f89a0c14da6766
Not sure what code to put in.
Changing color bit:
private void changeColourToolStripMenuItem_Click(object sender, EventArgs e)
{
DialogResult result = colorDialog1.ShowDialog();
}
I just dragged the elements on from the toolbox.
All Code:
using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Forms;
namespace Assignment
{
public partial class Form1 : Form
{
public Form1()
{
InitializeComponent();
init();
start();
this.DoubleBuffered = true;
}
//code to convert HSB to RGB from HSB.cs. All your code so i made it take up less space.
public struct HSBColor
{
float h;
float s;
float b;
int a;
public HSBColor(float h, float s, float b) { this.a = 0xff; this.h = Math.Min(Math.Max(h, 0), 255); this.s = Math.Min(Math.Max(s, 0), 255); this.b = Math.Min(Math.Max(b, 0), 255); }
public HSBColor(int a, float h, float s, float b) { this.a = a; this.h = Math.Min(Math.Max(h, 0), 255); this.s = Math.Min(Math.Max(s, 0), 255); this.b = Math.Min(Math.Max(b, 0), 255); }
public float H { get { return h; } }
public float S { get { return s; } }
public float B { get { return b; } }
public int A { get { return a; } }
public Color Color { get { return FromHSB(this); } }
public static Color FromHSB(HSBColor hsbColor)
{
float r = hsbColor.b;
float g = hsbColor.b;
float b = hsbColor.b;
if (hsbColor.s != 0)
{
float max = hsbColor.b; float dif = hsbColor.b * hsbColor.s / 255f; float min = hsbColor.b - dif; float h = hsbColor.h * 360f / 255f;
if (h < 60f) { r = max; g = h * dif / 60f + min; b = min; }
else if (h < 120f) { r = -(h - 120f) * dif / 60f + min; g = max; b = min; }
else if (h < 180f) { r = min; g = max; b = (h - 120f) * dif / 60f + min; }
else if (h < 240f) { r = min; g = -(h - 240f) * dif / 60f + min; b = max; }
else if (h < 300f) { r = (h - 240f) * dif / 60f + min; g = min; b = max; }
else if (h <= 360f) { r = max; g = min; b = -(h - 360f) * dif / 60 + min; }
else { r = 0; g = 0; b = 0; }
}
return Color.FromArgb(hsbColor.a, (int)Math.Round(Math.Min(Math.Max(r, 0), 255)), (int)Math.Round(Math.Min(Math.Max(g, 0), 255)), (int)Math.Round(Math.Min(Math.Max(b, 0), 255)));
}
}
private const int MAX = 256; // max iterations
private const double SX = -2.025; // start value real
private const double SY = -1.125; // start value imaginary
private const double EX = 0.6; // end value real
private const double EY = 1.125; // end value imaginary
private static int x1, y1, xs, ys, xe, ye;
private static double xstart, ystart, xende, yende, xzoom, yzoom;
private static float xy;
private int c = 0;
//private Image picture; Taken out, not needed
// create rectangle variable JGB
Rectangle rec;
private Graphics g1;
//private Cursor c1, c2; Taken out, not needed
private System.Drawing.Bitmap bitmap;
public void init()
{
//setSize(640, 480); changed this code to JGB:
this.Size = new Size(640, 480);
// Taken all lines out below. Not needed.
/*finished = false;
addMouseListener(this);
addMouseMotionListener(this);
c1 = new Cursor(Cursor.WAIT_CURSOR);
c2 = new Cursor(Cursor.CROSSHAIR_CURSOR); */
x1 = 640;
y1 = 480;
xy = (float)x1 / (float)y1;
//picture = createImage(x1, y1); Taken out and replaced with JGB:
bitmap = new Bitmap(x1, y1);
//g1 = picture.getGraphics(); changed to get my bitmap
g1 = Graphics.FromImage(bitmap);
//finished = true; Finished variable deleted so not needed
}
//Code below didnt appear to do anything so i deleted it
/*public void destroy() // delete all instances
{
if (finished)
{
removeMouseListener(this);
removeMouseMotionListener(this);
picture = null;
g1 = null;
c1 = null;
c2 = null;
System.gc(); // garbage collection
}
} */
public void start()
{
//action = false;
//rectangle = false;
initvalues();
// added dialog box for instance loading and save varaibles needed for position and zoom to text file
DialogResult dialog = MessageBox.Show("Would You Like to Load Your Last Instance?", "Load Instance?", MessageBoxButtons.YesNoCancel, MessageBoxIcon.Question);
if (dialog == DialogResult.Yes)
{
string[] lines = System.IO.File.ReadAllLines(#"C:\Users\Public\Writelines.txt");
xzoom = System.Convert.ToDouble(lines[0]);
yzoom = System.Convert.ToDouble(lines[1]);
xstart = System.Convert.ToDouble(lines[2]);
ystart = System.Convert.ToDouble(lines[3]);
}
else
{
xzoom = (xende - xstart) / (double)x1;
yzoom = (yende - ystart) / (double)y1;
}
mandelbrot();
}
public void stop()
{
}
/*public void paint(Graphics g, PaintEventArgs e)
{
update(g);
}
public void update(Graphics g)
{
//g.DrawImage(picture, 0, 0);
}*/
private void mandelbrot()
{
int x, y;
float h, b, alt = 0.0f;
Color color;
Pen pen = new Pen(Color.Black);
for (x = 0; x < x1; x += 2)
for (y = 0; y < y1; y++)
{
h = pointcolour(xstart + xzoom * (double)x, ystart + yzoom * (double)y, c);
if (h != alt)
{
b = 1.0f - h * h;
color = HSBColor.FromHSB(new HSBColor(h * 255, 0.8f * 255, b * 255));
pen = new Pen(color);
alt = h;
}
g1.DrawLine(pen, x, y, x + 1, y);
}
}
private float pointcolour(double xwert, double ywert, int j)
{
double r = 0.0, i = 0.0, m = 0.0;
// int j = 0;
while ((j < MAX) && (m < 4.0))
{
j++;
m = r * r - i * i;
i = 2.0 * r * i + ywert;
r = m + xwert;
}
return (float)j / (float)MAX;
}
private void initvalues()
{
xstart = SX;
ystart = SY;
xende = EX;
yende = EY;
if ((float)((xende - xstart) / (yende - ystart)) != xy)
xstart = xende - (yende - ystart) * (double)xy;
}
private void Form1_Paint(object sender, PaintEventArgs e)
{
Graphics g1 = e.Graphics;
g1.DrawImage(bitmap, 0, 0, x1, y1);
using (Pen pen = new Pen(Color.White, 2))
{
e.Graphics.DrawRectangle(pen, rec);
}
Invalidate();
}
//added load method
private void Form1_MouseMove(object sender, MouseEventArgs e)
{
if (e.Button == MouseButtons.Left)
{
xe = e.X;
ye = e.Y;
if (xs < xe)
{
if (ys < ye) rec = new Rectangle(xs, ys, (xe - xs), (ye - ys));
else rec = new Rectangle(xs, ye, (xe - xs), (ys - ye));
}
else
{
if (ys < ye) rec = new Rectangle(xe, ys, (xs - xe), (ye - ys));
else rec = new Rectangle(xe, ye, (xs - xe), (ys - ye));
}
this.Invalidate();
}
}
private void Form1_MouseDown(object sender, MouseEventArgs e)
{
if (e.Button == MouseButtons.Left)
{
// e.consume();
xs = e.X;
ys = e.Y; // starting point y
this.Invalidate();
}
}
private void Form1_MouseUp(object sender, MouseEventArgs e)
{
rec = new Rectangle(0, 0, 0, 0);
if (e.Button == MouseButtons.Left)
{
int z, w;
//e.consume();
//xe = e.X;
//ye = e.Y;
if (xs > xe)
{
z = xs;
xs = xe;
xe = z;
}
if (ys > ye)
{
z = ys;
ys = ye;
ye = z;
}
w = (xe - xs);
z = (ye - ys);
if ((w < 2) && (z < 2)) initvalues();
else
{
if (((float)w > (float)z * xy)) ye = (int)((float)ys + (float)w / xy);
else xe = (int)((float)xs + (float)z * xy);
xende = xstart + xzoom * (double)xe;
yende = ystart + yzoom * (double)ye;
xstart += xzoom * (double)xs;
ystart += yzoom * (double)ys;
}
xzoom = (xende - xstart) / (double)x1;
yzoom = (yende - ystart) / (double)y1;
mandelbrot();
string stringxzoom = xzoom.ToString();
string stringyzoom = yzoom.ToString();
string stringystart = ystart.ToString();
string stringxstart = xstart.ToString();
string[] lines = { stringxzoom, stringyzoom, stringxstart, stringystart };
System.IO.File.WriteAllLines(#"C:\Users\Public\Writelines.txt", lines);
this.Invalidate();
//Repaint();
}
}
private void saveToolStripMenuItem_Click(object sender, EventArgs e)
{
dialog.InitialDirectory =System.Environment.GetFolderPath(Environment.SpecialFolder.Personal);
dialog.Title = "Save Image";
dialog.FileName = "";
dialog.Filter = "JPEG|*.jpg";
dialog.ShowDialog();
}
private void restartToolStripMenuItem_Click(object sender, EventArgs e)
{
Application.Restart();
}
private void exitToolStripMenuItem1_Click(object sender, EventArgs e)
{
Application.Exit();
}
private void changeColourToolStripMenuItem_Click(object sender, EventArgs e)
{
colorDialog1.ShowDialog();
}
private void menuToolStripMenuItem_Click(object sender, EventArgs e)
{
}
private void menuStrip1_ItemClicked(object sender, ToolStripItemClickedEventArgs e)
{
}
}
}

Ok so after hours of trying to figure this out i found the solution. A random invalidate was messing it up.
Thanks anyway to #Sjips for the fast help.

Mandelbrot Conversion [closed]

Closed. This question needs debugging details. It is not currently accepting answers.
Edit the question to include desired behavior, a specific problem or error, and the shortest code necessary to reproduce the problem. This will help others answer the question.
Closed 8 years ago.
Improve this question
I'm receiving no errors but when I'm running it I'm also unable to see the Mandelbrot it just displays the grey box, I'm currently stuck at this one point thanks for any help, if you see any other parts of my code which contains grammar or coding errors it would be much appreciated if you told me.
using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Forms;
using System.Drawing.Drawing2D;
namespace SE_Fractal_Assignment
{
public partial class Form1 : Form
{
public Form1()
{
InitializeComponent();
}
public struct HSBColor
{
float h;
float s;
float b;
int a;
public HSBColor(float h, float s, float b)
{
this.a = 0xff;
this.h = Math.Min(Math.Max(h, 0), 255);
this.s = Math.Min(Math.Max(h, 0), 255);
this.b = Math.Min(Math.Max(h, 0), 255);
}
public float H
{
get { return h; }
}
public float S
{
get { return s; }
}
public float B
{
get { return b; }
}
public int A
{
get { return a; }
}
public Color Color
{
get
{
return FromHSB(this);
}
}
public static Color FromHSB(HSBColor hsbColor)
{
float r = hsbColor.b;
float g = hsbColor.b;
float b = hsbColor.b;
if (hsbColor.s != 0)
{
float max = hsbColor.b;
float dif = hsbColor.b * hsbColor.s / 255f;
float min = hsbColor.b - dif;
float h = hsbColor.h * 360f / 255f;
if (h < 60f)
{
r = max;
g = h * dif / 60f + min;
b = min;
}
else if (h < 120f)
{
r = -(h - 120f) * dif / 60f + min;
g = max;
b = min;
}
else if (h < 180f)
{
r = min;
g = max;
b = -(h - 120f) * dif / 60f + min;
}
else if (h < 240f)
{
r = min;
g = -(h - 240f) * dif / 60f + min;
b = max;
}
else if (h < 300f)
{
r = -(h - 240f) * dif / 60f + min;
g = min;
b = max;
}
else if (h <= 360f)
{
r = max;
g = min;
b = -(h - 360f) * dif / 60f + min;
}
else
{
r = 0;
g = 0;
b = 0;
}
}
return Color.FromArgb
(
hsbColor.a,
(int)Math.Round(Math.Min(Math.Max(r, 0), 255)),
(int)Math.Round(Math.Min(Math.Max(g, 0), 255)),
(int)Math.Round(Math.Min(Math.Max(b, 0), 255))
);
}
}
private const int MAX = 256; // max iterations
private const double SX = -2.025; // start value goal
private const double SY = -1.125; // start value imaginary
private const double EX = 0.6; // end value real
private const double EY = 1.125; // end value imaginary
private static int x1, y1, xs, ys, xe, ye;
private static double xstart, ystart, xende, yende, xzoom, yzoom;
private static bool action, rectangle, finished;
private static float xy;
//private Image picture1;
private System.Drawing.Bitmap bitmap;
private Graphics g1;
private Cursor c1, c2;
private HSBColor HSBcol = new HSBColor();
// private HSB HSBcol = new HSB();
private void Form1_Paint(object sender, PaintEventArgs e)
{
g1 = e.Graphics;
g1.DrawImage(bitmap, 0, 0, x1, y1);
g1.Dispose();
}
private void Form1_Load(object sender, EventArgs e)
{
init();
start();
}
public void init()
{
//HSBcol = new HSB();
finished = false;
c1 = Cursors.WaitCursor;
c2 = Cursors.Cross;
x1 = 640;
y1 = 480;
xy = (float)x1 / (float)y1;
bitmap.SetPixel(x1, y1, Color.Blue);
g1 = Graphics.FromImage(bitmap);
finished = true;
// xy = (float)x1 / (float)y1;
//picture = createImage(x1, y1);
//g1 = picture.getGraphics();
}
public void destroy() // delete all instances
{
if (finished)
{
//removeMouseListener(this);
//removeMouseMotionListener(this);
//bitmap = null;
g1 = null;
c1 = null;
c2 = null;
//System.gc(); // garbage collection
GC.Collect();
}
}
public void start()
{
action = false;
rectangle = false;
initvalues();
xzoom = (xende - xstart) / (double)x1;
yzoom = (yende - ystart) / (double)y1;
mandelbrot();
}
public void stop()
{
}
public void paint(Graphics g)
{
update(g);
}
public void update(Graphics g)
{
/* Pen myPen = new Pen(Color.White);
g.DrawImage(bitmap, 0, 0);
if (rectangle)
{
if (xs < xe)
{
if (ys < ye)
{
g.DrawRectangle(myPen, xs, ys, (xe - xs), (ye - ys));
}
}
else
{
g.DrawRectangle(myPen, xs, ys, (xe - xs), (ye - ys));
}
myPen.Dispose();
}*/
}
private void mandelbrot() // calculate all points
{
int x, y;
float h, b, alt = 0.0f;
action = false;
for (x = 0; x < x1; x += 2)
for (y = 0; y < y1; y++)
{
h = pointcolour(xstart + xzoom * (double)x, ystart + yzoom * (double)y);
// color value
if (h != alt)
{
b = 1.0f - h * h; // brightnes
///djm added
///HSBcol.fromHSB(h,0.8f,b);
///
//convert hsb to rgb then make a Java Color
Color color = HSBColor.FromHSB(new HSBColor(h * 255, 0.8f * 255, b * 255));
///g1.setColor(col);
//djm end
//djm added to convert to RGB from HSB
//g1.setColor(Color.getHSBColor(h, 0.8f, b));
//djm test
// Color col = Color.FromArgb(0, 0, 0, 0);
//red = Color.Red;
// green = Color.Green;
// blue = Color.Blue;
//djm
alt = h;
}
Pen pen = new Pen(Color.Aqua);
g1.DrawLine(pen, x, y, x + 1, y);
}
//showStatus("Mandelbrot-Set ready - please select zoom area with pressed mouse.");
//setCursor(c2);
action = true;
}
private float pointcolour(double xwert, double ywert)
// color value from 0.0 to 1.0 by iterations
{
double r = 0.0, i = 0.0, m = 0.0;
int j = 0;
while ((j < MAX) && (m < 4.0))
{
j++;
m = r * r - i * i;
i = 2.0 * r * i + ywert;
r = m + xwert;
}
return (float)j / (float)MAX;
}
private void initvalues() // reset start values
{
xstart = SX;
ystart = SY;
xende = EX;
yende = EY;
if ((float)((xende - xstart) / (yende - ystart)) != xy)
xstart = xende - (yende - ystart) * (double)xy;
}
private void Form1_paint(object sender, PaintEventArgs e)
{
Graphics g = e.Graphics;
g1 = g;
action = false;
rectangle = false;
initvalues();
xzoom = (xende - xstart) / (double)x1;
yzoom = (yende - ystart) / (double)y1;
//picture = g.DrawImage;
//g.DrawImage(picture,0,0);
update(g);
mandelbrot();
}
private void Form1_MouseDown(object sender, MouseEventArgs e)
{
if (action)
{
xs = e.X;
ys = e.Y;
}
}
private void Form1_MouseMove(object sender, MouseEventArgs e)
{
// e.consume();
if (action)
{
xe = e.X;
ye = e.Y;
rectangle = true;
//repaint();
}
}
private void Form1_MouseUp(object sender, MouseEventArgs e)
{
rectangle = false;
}
private void Form1_Click(object sender, MouseEventArgs e)
{
}
public String getAppletInfo()
{
return "fractal.class - Mandelbrot Set a Java Applet by Eckhard Roessel 2000-2001";
}
}
}

Honestly, the code is so cluttered and disorganized, it's hard to know all of what might be wrong with it. Sorry to be so blunt.
That said, a couple of obvious problems I see involving your "g1" Graphics instance member.
First, you are using the same field for two purposes: when computing the original image, you expect this to be a Graphics instance you can use to draw into your bitmap. But in the Paint event, you set it to the Graphics instance for the window, into which the painting should be done.
Second, in that Paint event, you dispose the Graphics instance before you return. But the instance you're disposing isn't yours. It belongs to the Forms system, and the only thing you should be doing with it is drawing into it.
There actually appear to be two different Paint event handlers and it's not clear which one you're using. You only dispose the Graphics instance in one of those places, so that may or may not be the real problem.
Personally, I would break the problem down into different elements. For a relative novice, it can be hard enough just to correctly draw a bitmap. It can also be difficult to really grasp how Paint event handling should be done. And of course, there's the Mandelbrot computations themselves. Trying to implement all three things (and more) at the same time can be overwhelming, and will take a lot longer assuming you can figure it out at all.
I would start by writing a simple program that just has a single PictureBox, which when you click a button, your program creates a new Bitmap object, into which you draw something simple (say, a rectangle, circle, or maybe just some text) and then assigns that Bitmap object to the PictureBox.Image property.
Once you have that working, then you can change the drawing part of the code to draw a Mandelbrot image instead.
Finally, once you have that working, then you can work on using the Paint event to draw the bitmap into your window directly instead of using the PictureBox control (the main reason for wanting to do this would presumably be that you eventually want to update the image as it's being drawn...if you only want to show it at the very end, then IMHO the PictureBox is a better approach).

Losing correct position by zooming in c#

I have a image in a picture box.it contains a Triangle.
I have a another picture box that contain a little Circle. i should put Circle on top of Triangle . i Zoom first image(Triangle ) to find top of it and then put Circle there.i do it correctly . but when i reset zoom , top of Triangle will be lose and Circle will be on a wrong position.
my code for zoom:
protected override void OnMouseWheel(MouseEventArgs e)
{
this.Cursor = Cursors.Default;
float oldzoom = zoom;
if (e.Delta > 0)
{
zoom += 0.625f;
zoomPerectNum += 50;
_txt_precentZoom.Text = zoomPerectNum.ToString() + "%";
}
else if (e.Delta < 0)
{
// zoom = Math.Max(zoom - 1F, 1F);
zoom = zoom - 0.625F;
if (zoom < 0.2503874F)
{
zoom = 0.2503874F;
}
else
{
zoomPerectNum -= 50;
_txt_precentZoom.Text = zoomPerectNum.ToString() + "%";
}
}
MouseEventArgs mouse = e as MouseEventArgs;
Point mousePosNow = mouse.Location;
int x = mousePosNow.X - _pic_image.Location.X; // Where location of the mouse in the pictureframe
int y = mousePosNow.Y - _pic_image.Location.Y;
int oldimagex = (int)(x / oldzoom); // Where in the IMAGE is it now
int oldimagey = (int)(y / oldzoom);
int newimagex = (int)(x / zoom); // Where in the IMAGE will it be when the new zoom i made
int newimagey = (int)(y / zoom);
imgx = newimagex - oldimagex + imgx; // Where to move image to keep focus on one point
imgy = newimagey - oldimagey + imgy;
_pic_image.Refresh(); // calls imageBox_Paint
}
private void imageBox_Paint(object sender, PaintEventArgs e)
{
e.Graphics.InterpolationMode = InterpolationMode.HighQualityBicubic;
e.Graphics.ScaleTransform(zoom, zoom);
if (img != null)
{
e.Graphics.DrawImage(img, imgx, imgy);
}
}
_pic_Circle:
private void _pic_Circle_MouseDown(object sender, MouseEventArgs e)
{
dragging = true;
dragPoint = new Point(e.X, e.Y);
}
private void _pic_Circle_MouseMove(object sender, MouseEventArgs e)
{
if (dragging)
{
_pic_Circle.Location = new Point(_pic_Circle.Location.X + e.X - dragPoint.X, _pic_Circle.Location.Y + e.Y - dragPoint.Y);
}
}
private void _pic_Circle_MouseUp(object sender, MouseEventArgs e)
{
dragging = false;
}