Painting and zooming

[Frans Vander Meiren]

Hi

Via an adapted Paint-method I try to zoom in on a part of a bitmap (8 x 8
pixels). So I defined the source rectangle of the image and the destination
rectangle on my application form (see code). That works well, but the pixels
of the first row and the first column are only rendered for half the size.
Can anyone explain that ...?

Thx
Frans
protected override void OnPaint(PaintEventArgs e)
{
// destination rectangle
Rectangle rectDst = new Rectangle();

rectDst.X = 0;
rectDst.Y = 0;
rectDst.Width = 320;
rectDst.Height = 320;

// source rectangle
Rectangle rectSrc = new Rectangle();

rectSrc.X = 0;
rectSrc.Y = 0;
rectSrc.Width = 8;
rectSrc.Height = 8;

// draw (part of the image)
Graphics g = e.Graphics;
g.InterpolationMode = InterpolationMode.NearestNeighbor ;
g.DrawImage( Bm, rectDst, rectSrc, GraphicsUnit.Pixel );
}

[Bob Powell [MVP]]

This is a common problem. Set the PixelOffsetMode to half.

--
Bob Powell [MVP]
Visual C#, System.Drawing

Ramuseco Limited .NET consulting
http://www.ramuseco.com

Find great Windows Forms articles in Windows Forms Tips and Tricks
http://www.bobpowell.net/tipstricks.htm

Answer those GDI+ questions with the GDI+ FAQ
http://www.bobpowell.net/faqmain.htm

All new articles provide code in C# and VB.NET.
Subscribe to the RSS feeds provided and never miss a new article.

"Frans Vander Meiren" <Fr***************@discussions.microsoft.com> wrote in
message news:3E**********************************@microsof t.com...

Hi

Via an adapted Paint-method I try to zoom in on a part of a bitmap (8 x 8
pixels). So I defined the source rectangle of the image and the
destination
rectangle on my application form (see code). That works well, but the
pixels
of the first row and the first column are only rendered for half the size.
Can anyone explain that ...?

Thx
Frans
protected override void OnPaint(PaintEventArgs e)
{
// destination rectangle
Rectangle rectDst = new Rectangle();

rectDst.X = 0;
rectDst.Y = 0;
rectDst.Width = 320;
rectDst.Height = 320;

// source rectangle
Rectangle rectSrc = new Rectangle();

rectSrc.X = 0;
rectSrc.Y = 0;
rectSrc.Width = 8;
rectSrc.Height = 8;

// draw (part of the image)
Graphics g = e.Graphics;
g.InterpolationMode = InterpolationMode.NearestNeighbor ;
g.DrawImage( Bm, rectDst, rectSrc, GraphicsUnit.Pixel );
}

[Frans Vander Meiren]

Thanks Bob. It works ...

"Bob Powell [MVP]" wrote:

This is a common problem. Set the PixelOffsetMode to half.

--
Bob Powell [MVP]
Visual C#, System.Drawing

Ramuseco Limited .NET consulting
http://www.ramuseco.com

Find great Windows Forms articles in Windows Forms Tips and Tricks
http://www.bobpowell.net/tipstricks.htm

Answer those GDI+ questions with the GDI+ FAQ
http://www.bobpowell.net/faqmain.htm

All new articles provide code in C# and VB.NET.
Subscribe to the RSS feeds provided and never miss a new article.

"Frans Vander Meiren" <Fr***************@discussions.microsoft.com> wrote in
message news:3E**********************************@microsof t.com...

Hi

Via an adapted Paint-method I try to zoom in on a part of a bitmap (8 x 8
pixels). So I defined the source rectangle of the image and the
destination
rectangle on my application form (see code). That works well, but the
pixels
of the first row and the first column are only rendered for half the size.
Can anyone explain that ...?

Thx
Frans
protected override void OnPaint(PaintEventArgs e)
{
// destination rectangle
Rectangle rectDst = new Rectangle();

rectDst.X = 0;
rectDst.Y = 0;
rectDst.Width = 320;
rectDst.Height = 320;

// source rectangle
Rectangle rectSrc = new Rectangle();

rectSrc.X = 0;
rectSrc.Y = 0;
rectSrc.Width = 8;
rectSrc.Height = 8;

// draw (part of the image)
Graphics g = e.Graphics;
g.InterpolationMode = InterpolationMode.NearestNeighbor ;
g.DrawImage( Bm, rectDst, rectSrc, GraphicsUnit.Pixel );
}