2D Graphics

Bit operation with PixelFormat.Alpha

Posted on by coder 
   
  
using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Drawing.Drawing2D;
using System.Drawing.Imaging;

using System.Text;
using System.Windows.Forms;

public class MainClass {

    public static void Main() {
        // Create two new bitmap images
        Bitmap bmp1 = new Bitmap(100, 100, PixelFormat.Format32bppArgb);
        Bitmap bmp2 = new Bitmap(100, 100, PixelFormat.Format24bppRgb);

        // Test for alpha 
        bool b1 = ((bmp1.PixelFormat & PixelFormat.Alpha) != 0);
        bool b2 = ((bmp2.PixelFormat & PixelFormat.Alpha) != 0);

        // Output results to console window
        Console.WriteLine("bmp1 has alpha?: " + b1);
        Console.WriteLine("bmp2 has alpha?: " + b2);

        // Clean up
        bmp1.Dispose();
        bmp2.Dispose();
    }
}

Draw an array of images

Posted on by coder 


   
  
using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Text;
using System.Windows.Forms;

public class MainForm : Form {
    private Bitmap[] myImages = new Bitmap[3];
    public MainForm() {
        myImages[0] = new Bitmap("imageA.bmp");
        myImages[1] = new Bitmap("imageB.bmp");
        myImages[2] = new Bitmap("imageC.bmp");
    }

    protected void OnPaint(PaintEventArgs e) {
        Graphics g = e.Graphics;
        int yOffset = 10;
        foreach (Bitmap b in myImages) {
            g.DrawImage(b, 10, yOffset, 90, 90);
            yOffset += 100;
        }
    }
    public static void Main() {
        Application.Run(new MainForm());
    }
}

Double buffer with Bitmap

Posted on by coder 
   
  
using System;
using System.Drawing;
using System.Windows.Forms;

public class Form1 : Form {
    Pen p;
    SolidBrush b, bT = new SolidBrush(Color.Black);
    string path = "5.bmp";
    Image im;
    Font f;

    public Form1() {
        Color cP = Color.Gray;
        Color cB = Color.LightGray;

        p = new Pen(cP, 6);
        b = new SolidBrush(cB);
        im = Image.FromFile(path);
        f = new Font(new FontFamily("Times New Roman"), 10);
    }
    static void Main() {
        Application.Run(new Form1());
    }
    protected override void OnPaint(PaintEventArgs pea) {
        Sketch();
        //SketchDBuf();
    }
    private void Sketch() {
        Graphics g = Graphics.FromHwnd(this.Handle);

        g.FillRectangle(b, 4, 4, 260, 220);
        g.DrawRectangle(p, 4, 4, 260, 220);
        g.DrawImage(im, 33, 35, 200, 145);
        g.DrawString("AAAAAA", f, bT, 180, 190);

        g.Dispose();
    }
    private void SketchDBuf() {
        int hh = 3, w = 260, h = 220;

        Graphics g;
        Bitmap bm = new Bitmap(w + 2 * hh, h + 2 * hh);
        g = Graphics.FromImage(bm);

        g.FillRectangle(b, hh, hh, w, h);
        g.DrawRectangle(new Pen(Color.Gray, 2 * hh), hh, hh, w, h);
        g.DrawImage(im, hh + 30, hh + 32, 200, 145);
        g.DrawString("Text", f, bT, 180, 190);
        g = Graphics.FromHwnd(this.Handle);
        g.DrawImage(bm, 1, 1);

        g.Dispose();
    }
}

write the pixel information to the console window

Posted on by coder

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Text;
using System.Windows.Forms;

public class Form1 : Form {

protected override void OnPaint(PaintEventArgs e) {
Graphics gForm = e.Graphics;
gForm.FillRectangle(Brushes.White, this.ClientRectangle);
Bitmap bmp = new Bitmap(6, 6);
Graphics gBmp = Graphics.FromImage(bmp);

gBmp.FillRectangle(Brushes.White, 0, 0, bmp.Width, bmp.Height);
gBmp.DrawLine(Pens.Red, 0, 0, 5, 5);
gForm.DrawImage(bmp, 20, 20, bmp.Width, bmp.Height);

for (int y = 0; y < bmp.Height; ++y) { for (int x = 0; x < bmp.Width; ++x) { Color c = bmp.GetPixel(x, y); Console.Write("{0,2:x}{1,2:x}{2,2:x}{3,2:x} ",c.A, c.R, c.G, c.G); } Console.WriteLine(); } bmp.Dispose(); } public static void Main() { Application.Run(new Form1()); } } [/csharp]

Create a green color with an alpha component then draw a green rectangle to the bitmap in memory

Posted on by coder

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Text;
using System.Windows.Forms;

public class Form1 : Form {

protected override void OnPaint(PaintEventArgs e) {
Graphics gForm = e.Graphics;
gForm.FillRectangle(Brushes.White, this.ClientRectangle);
for (int i = 1; i <= 7; ++i) { Rectangle r = new Rectangle(i * 40 - 15, 0, 15, this.ClientRectangle.Height); gForm.FillRectangle(Brushes.Orange, r); } Bitmap bmp = new Bitmap(260, 260, System.Drawing.Imaging.PixelFormat.Format32bppArgb); Graphics gBmp = Graphics.FromImage(bmp); Color green = Color.FromArgb(0x40, 0, 0xff, 0); Brush greenBrush = new SolidBrush(green); gBmp.FillRectangle(greenBrush, 10, 10, 140, 140); gForm.DrawImage(bmp, 20, 20, bmp.Width, bmp.Height); bmp.Dispose(); gBmp.Dispose(); greenBrush.Dispose(); } public static void Main() { Application.Run(new Form1()); } } [/csharp]

Create a red color with an alpha component then draw a red circle to the bitmap in memory

Posted on by coder

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Text;
using System.Windows.Forms;

public class Form1 : Form {

protected override void OnPaint(PaintEventArgs e) {
Graphics gForm = e.Graphics;
gForm.FillRectangle(Brushes.White, this.ClientRectangle);
for (int i = 1; i <= 7; ++i) { Rectangle r = new Rectangle(i * 40 - 15, 0, 15,this.ClientRectangle.Height); gForm.FillRectangle(Brushes.Orange, r); } Bitmap bmp = new Bitmap(260, 260,System.Drawing.Imaging.PixelFormat.Format32bppArgb); Graphics gBmp = Graphics.FromImage(bmp); Color red = Color.FromArgb(0x60, 0xff, 0, 0); Brush redBrush = new SolidBrush(red); gBmp.FillEllipse(redBrush, 70, 70, 160, 160); gForm.DrawImage(bmp, 20, 20, bmp.Width, bmp.Height); bmp.Dispose(); gBmp.Dispose(); redBrush.Dispose(); } public static void Main() { Application.Run(new Form1()); } } [/csharp]

Create a Bitmap image in memory and set its CompositingMode

Posted on by coder

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Text;
using System.Windows.Forms;

public class Form1 : Form {

protected override void OnPaint(PaintEventArgs e) {
Graphics gForm = e.Graphics;
gForm.FillRectangle(Brushes.White, this.ClientRectangle);
for (int i = 1; i <= 7; ++i) { Rectangle r = new Rectangle(i * 40 - 15, 0, 15, this.ClientRectangle.Height); gForm.FillRectangle(Brushes.Orange, r); } Bitmap bmp = new Bitmap(260, 260,System.Drawing.Imaging.PixelFormat.Format32bppArgb); Graphics gBmp = Graphics.FromImage(bmp); gBmp.CompositingMode = System.Drawing.Drawing2D.CompositingMode.SourceCopy; gForm.DrawImage(bmp, 20, 20, bmp.Width, bmp.Height); bmp.Dispose(); gBmp.Dispose(); } public static void Main() { Application.Run(new Form1()); } } [/csharp]