.NET Framework - I need to zoom a bitmap with no interpolation

I'm making a small Paint-like program and when I zoom in I want to see each
individual pixel as its own block of solid color. Everything I've tried with
the Graphics methods has resulted in smoothed images, even if I use
InterpolationMode.Low. Is there any way to get .NET to do this for me or am
I going to have to walk through every pixel and paint my own rectangles?

  Michael C replied...

e.Graphics.InterpolationMode = InterpolationMode.NearestNeighbor;
e.Graphics.PixelOffsetMode = PixelOffsetMode.Half;

Second line is optional

  Michael C replied...

BTW, here's the complete code I use to test the different enum values. Paste
this into a form and run and you will get a very clear idea of what each of
the enums does.

protected override void OnPaint(PaintEventArgs e)
{
Bitmap bitmap = new Bitmap(2, 2, PixelFormat.Format24bppRgb);
bitmap.SetPixel(0, 0, Color.Red);
bitmap.SetPixel(0, 1, Color.Green);
bitmap.SetPixel(1, 0, Color.Blue);
bitmap.SetPixel(1, 1, Color.Orange);
e.Graphics.InterpolationMode = InterpolationMode.NearestNeighbor;
e.Graphics.PixelOffsetMode = PixelOffsetMode.Half;
e.Graphics.DrawImage(bitmap, this.ClientRectangle);
bitmap.Dispose();
}

  Jeff Johnson replied...

Wow, I feel like a lazy bum now. A simple search on "nearest neighbor
interpolation" gave me the exact answer (as did you). Thanks for the
pointer!

ReaderWriterLockSlim + Dispose? .NET Framework One last question today :) Most locks I've used never had a Dispose (Monitor, ReaderWriterLock, etc). Looking at the ReaderWriterLockSlim's Dispose method its just cleaning up some Threading.WaitHandle's. Whenever I see a Dispose method I always want to call it after I'm done with the object. All examples I've ever found online don't use dispose with the ReaderWriterLockSlim. Making my classes that use this lock IDisposable for this reasion alone ReaderWriterLockSlim? Is there performance increases in using the disposable WaitHandles vs how other locks without Dispose() do it? Thanks :) I'm mostly just curious. NB C# Discussions ThreadPool.QueueUserWorkItem (1) ReaderWriterLockSlim.Dispose (1) RWLS.Aquire (1) System.Collections.Generic (1) ObjectDisposedException (1) QueueUserWorkItem (1) ReaderWriterLock (1) AutoResetEvent that implement IDisposable, they "just" clean up some things. Are you implying that the ReaderWriterLockSlim.Dispose() is less important than for other classes that implement IDisposable? Yes. Do you mean that

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that region here. Indicate which line you added / changed to try to change the background color. protected void InitializeComponent() { System.ComponentModel.ComponentResourceManager resources = new System.ComponentModel.ComponentResourceManager(typeof(InvoiceForm)); this.textBox17 SuspendLayout(); this.panel7.SuspendLayout(); this.panel6.SuspendLayout(); this.SuspendLayout(); / / / / textBox17 / / this.textBox17.BackColor = System.Drawing.Color.GhostWhite; this.textBox17.BorderStyle = System.Windows.Forms.BorderStyle.FixedSingle; this.textBox17.Location = new System.Drawing textBox17.KeyPress + = new System.Windows.Forms.KeyPressEventHandler(this.keypressed17); / / / / textBox15 / / this.textBox15.BackColor = System.Drawing.Color.GhostWhite; this.textBox15.BorderStyle = System.Windows.Forms.BorderStyle.None; this.textBox15.Location = new System.Drawing System.Drawing.Size(576, 124); this.textBox15.TabIndex = 0; / / / / textBox7 / / this.textBox7.BackColor = System.Drawing.Color.FromArgb(((int)(((byte)(219)))), ((int)(((byte)(219)))), ((int)(((byte)(200))))); this.textBox7.BorderStyle = System.Windows System.Drawing.Size(156, 20); this.textBox7.TabIndex = 5; / / / / textBox6 / / this.textBox6.BackColor = System.Drawing.Color.FromArgb(((int)(((byte)(219)))), ((int)(((byte)(219)))), ((int)(((byte)(200))))); this.textBox6.BorderStyle = System.Windows System.Drawing.Size(176, 20); this.textBox6.TabIndex = 12; / / / / textBox5 / / this.textBox5.BackColor = System.Drawing.Color.FromArgb(((int)(((byte)(219)))), ((int)(((byte)(219)))), ((int)(((byte)(200))))); this.textBox5.BorderStyle = System.Windows System.Drawing.Size(176, 20); this.textBox5.TabIndex = 11; / / / / textBox4 / / this.textBox4.BackColor = System.Drawing.Color.FromArgb(((int)(((byte)(219)))), ((int)(((byte)(219)))), ((int)(((byte)(200))))); this.textBox4.BorderStyle = System.Windows System.Drawing.Size(176, 20); this.textBox4.TabIndex = 10; / / / / textBox3 / / this.textBox3.BackColor = System.Drawing.Color.FromArgb(((int)(((byte)(219)))), ((int)(((byte)(219)))), ((int)(((byte)(200))))); this.textBox3.BorderStyle = System.Windows

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