Getting Bitmap to save to file

Question

Hi, I have a program that generates a Madelbrot Set in a picturebox and I want to save it to a file but when I call a picturebox1.save(...path) function all I get is a blank image, could anyone help me sort this out

using System;
using System.Drawing;
using System.Collections;
using System.ComponentModel;
using System.Windows.Forms;
using System.Data;
using System.Design;
using System.Drawing.Drawing2D;


namespace Assignment
{

    /// <summary>
    /// Summary description for Form1.
    /// </summary>
    public class Form1 : System.Windows.Forms.Form
    {
        private System.Windows.Forms.PictureBox pictureBox1;
        private Button button1;
        private Button button2;
        private Button button3;
        /// <summary>
        /// Required designer variable.
        /// </summary>
        private System.ComponentModel.Container components = null;
        private Label label1;
        Rectangle rect;
        public Form1()
        {

            InitializeComponent();
            Image bp = new Bitmap(this.pictureBox1.Height, this.pictureBox1.Width);
            pictureBox1.Image = bp;
            Graphics g1 = Graphics.FromImage(bp);
            this.DoubleBuffered = true;
        }




        /// <summary>
        /// Clean up any resources being used.
        /// </summary>
        protected override void Dispose(bool disposing)
        {
            if (disposing)
            {
                if (components != null)
                {
                    components.Dispose();
                }
            }
            base.Dispose(disposing);
        }

        #region Windows Form Designer generated code
        /// <summary>
        /// Required method for Designer support - do not modify
        /// the contents of this method with the code editor.
        /// </summary>
        private void InitializeComponent()
        {
            System.ComponentModel.ComponentResourceManager resources = new System.ComponentModel.ComponentResourceManager(typeof(Form1));
            this.pictureBox1 = new System.Windows.Forms.PictureBox();
            this.button1 = new System.Windows.Forms.Button();
            this.button2 = new System.Windows.Forms.Button();
            this.button3 = new System.Windows.Forms.Button();
            this.label1 = new System.Windows.Forms.Label();
            ((System.ComponentModel.ISupportInitialize)(this.pictureBox1)).BeginInit();
            this.SuspendLayout();
            // 
            // pictureBox1
            // 
            this.pictureBox1.BackColor = System.Drawing.SystemColors.Control;
            this.pictureBox1.BorderStyle = System.Windows.Forms.BorderStyle.FixedSingle;
            this.pictureBox1.Cursor = System.Windows.Forms.Cursors.Cross;
            this.pictureBox1.Location = new System.Drawing.Point(57, 77);
            this.pictureBox1.Name = "pictureBox1";
            this.pictureBox1.Size = new System.Drawing.Size(471, 305);
            this.pictureBox1.TabIndex = 0;
            this.pictureBox1.TabStop = false;
            this.pictureBox1.WaitOnLoad = true;
            this.pictureBox1.MouseMove += new System.Windows.Forms.MouseEventHandler(this.pictureBox1_MouseMove);
            this.pictureBox1.MouseDown += new System.Windows.Forms.MouseEventHandler(this.pictureBox1_MouseDown);
            this.pictureBox1.Paint += new System.Windows.Forms.PaintEventHandler(this.pictureBox1_Paint);
            this.pictureBox1.MouseUp += new System.Windows.Forms.MouseEventHandler(this.pictureBox1_MouseUp);
            // 
            // button1
            // 
            this.button1.Location = new System.Drawing.Point(587, 77);
            this.button1.Name = "button1";
            this.button1.Size = new System.Drawing.Size(72, 52);
            this.button1.TabIndex = 1;
            this.button1.Text = "Create Fractal";
            this.button1.UseVisualStyleBackColor = true;
            this.button1.Click += new System.EventHandler(this.button1_Click);
            // 
            // button2
            // 
            this.button2.Location = new System.Drawing.Point(587, 135);
            this.button2.Name = "button2";
            this.button2.Size = new System.Drawing.Size(72, 52);
            this.button2.TabIndex = 2;
            this.button2.Text = "Clear Fractal";
            this.button2.UseVisualStyleBackColor = true;
            this.button2.Click += new System.EventHandler(this.button2_Click_1);
            // 
            // button3
            // 
            this.button3.Location = new System.Drawing.Point(587, 193);
            this.button3.Name = "button3";
            this.button3.Size = new System.Drawing.Size(75, 52);
            this.button3.TabIndex = 3;
            this.button3.Text = "Save Fractal";
            this.button3.UseVisualStyleBackColor = true;
            this.button3.Click += new System.EventHandler(this.button3_Click);
            // 
            // label1
            // 
            this.label1.AutoSize = true;
            this.label1.Font = new System.Drawing.Font("Microsoft Sans Serif", 30F, System.Drawing.FontStyle.Regular, System.Drawing.GraphicsUnit.Point, ((byte)(0)));
            this.label1.Location = new System.Drawing.Point(49, 9);
            this.label1.Name = "label1";
            this.label1.Size = new System.Drawing.Size(533, 46);
            this.label1.TabIndex = 4;
            this.label1.Text = "Mandelbrot Set - Chris Byrne";
            // 
            // Form1
            // 
            this.AutoScaleBaseSize = new System.Drawing.Size(5, 13);
            this.BackColor = System.Drawing.SystemColors.Control;
            this.ClientSize = new System.Drawing.Size(780, 394);
            this.Controls.Add(this.label1);
            this.Controls.Add(this.button3);
            this.Controls.Add(this.button2);
            this.Controls.Add(this.button1);
            this.Controls.Add(this.pictureBox1);
            this.DoubleBuffered = true;
            this.Icon = ((System.Drawing.Icon)(resources.GetObject("$this.Icon")));
            this.MaximizeBox = false;
            this.Name = "Form1";
            this.Text = "Mandelbrot Set";
            ((System.ComponentModel.ISupportInitialize)(this.pictureBox1)).EndInit();
            this.ResumeLayout(false);
            this.PerformLayout();

        }
        #endregion

        /// <summary>
        /// The main entry point for the application.
        /// </summary>
        [STAThread]
        static void Main()
        {
            Application.Run(new Form1());

        }
        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 bool action, finished;
        private static float xy;
        Graphics g1;



        public void init() // all instances will be prepared
        {

            g1 = pictureBox1.CreateGraphics();

            finished = false;
            x1 = this.pictureBox1.Width;
            y1 = this.pictureBox1.Height;
            xy = (float)x1 / (float)y1;
            finished = true;
            mandelbrot();
            start();
        }
        public void destroy() // delete all instances 
        {
            if (finished)
            {
                g1 = null;
                GC.Collect(); // garbage collection
            }
        }
        public void start()
        {
            action = false;
            initvalues();
            xzoom = (xende - xstart) / (double)x1;
            yzoom = (yende - ystart) / (double)y1;
            mandelbrot();
        }
        public void stop()
        {
        }

        public void paint(Graphics g)
        {
            //update(g); 
        }
        //Do Mandelbrot next
        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)
                    {
                        alt = h * 255;
                        b = 1.0f - h * h; // brightnes
                        
                        Color color = HSBColor.FromHSB(new HSBColor(h * 255, 0.8f * 255, b * 255));  // VERY IMPORTANT


                        Pen pen = new Pen(color);
                        g1.DrawLine(pen, x, y, x + 1, y);
                        
                    }


                }
            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 pictureBox1_MouseDown(object sender, System.Windows.Forms.MouseEventArgs e)
        {
            rect = new Rectangle(e.X, e.Y, 0, 0);
            this.Invalidate();
            if (action)
            {
                xs = e.X;
                ys = e.Y;
            }


        }

        private void pictureBox1_MouseMove(object sender, System.Windows.Forms.MouseEventArgs e)
        {
            if (e.Button == MouseButtons.Left)
            {
                // Draws the rectangle as the mouse moves
                rect = new Rectangle(rect.Left, rect.Top, e.X - rect.Left, e.Y - rect.Top);
            }
            this.Invalidate();
            if (action)
            {
                xe = e.X;
                ye = e.Y;
            }

        }

        private void pictureBox1_MouseUp(object sender, System.Windows.Forms.MouseEventArgs e)
        {
            int z, w;
            this.pictureBox1.Refresh();
            if (action)
            {
                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();

            }

        }

        private void button1_Click(object sender, EventArgs e)
        {
            init();
            start();
            button1.Enabled = false;
            button1.Text = "Fractal Created";
        }

        private void button2_Click(object sender, EventArgs e)
        {

        }

        private void button2_Click_1(object sender, EventArgs e)
        {
            DialogResult reply = MessageBox.Show("Do you want to clear the fractal?",
"Clear Fractal?", MessageBoxButtons.YesNo, MessageBoxIcon.Question);

            if (reply == DialogResult.Yes)
            {
                this.pictureBox1.Invalidate();
                this.pictureBox1.Refresh();
                button1.Enabled = true;
            }
            else
            {

            }

        }

        private void button3_Click(object sender, EventArgs e)
        {

            pictureBox1.Image.Save("C:\\myfractal.bmp", ImageFormatConverter.Bmp);
            Byte[] b = File.ReadAllBytes("myfractal.bmp");

        }

        private void pictureBox1_Paint(object sender, PaintEventArgs e)
        {
            //using (Pen pen = new Pen(Color.Black, 2))
            {
            //    e.Graphics.DrawRectangle(pen, rect);
            }




        }

    }
}

The code is in the button 3 click event, but I thought I would post all of my code in case you need it.

Answer 1

G1 can draw to different surfaces depending upon its value.  Are you drawing to the screen or to the image?

Answer 2

Im drawing to a bitmap which is being displayed in the picturebox, I just want what is in the picturebox to be saved as an image file

Answer 3

Im drawing to a bitmap which is being displayed in the picturebox, I just want what is in the picturebox to be saved as an image file

How do you know?  What is the purpose of this line:

 g1 = pictureBox1.CreateGraphics();

 

Answer 4

To be honest, Im not 100% sure, I just know that without it, it wont draw the fractal.

Is there any way I can save the image with the code I have, or do I need to make changes?

Sorry for all these questions..

Answer 5

To be honest, Im not 100% sure, I just know that without it, it wont draw the fractal.

Is there any way I can save the image with the code I have, or do I need to make changes?

Sorry for all these questions..

You can save the image which is empty, but if you want to save a copy of what you drew to the screen, i'd suggest you draw to the image rather than to the screen.