split image

[jimpie]

Hello,

I want to make a picture splitter, this means when i have a picture from 64x64 it should split is to 4 images of 32x32

how will I code this?

Thanks,

Jimpie

[jmcilhinney]

You create a new Bitmap of the appropriate size, call Graphics.FromImage to create a Graphics object, then call Graphics.DrawImage to draw the appropriate part of the original Image onto the new Image. Do that four times and you've got your wish. You should read the documentation for Graphics.DrawImage to find the appropriate overload to call.

[jimpie]

You create a new Bitmap of the appropriate size, call Graphics.FromImage to create a Graphics object, then call Graphics.DrawImage to draw the appropriate part of the original Image onto the new Image. Do that four times and you've got your wish. You should read the documentation for Graphics.DrawImage to find the appropriate overload to call.

Hello,

I can't get it working, i've never worked with splitting bitmaps before. I tried diffrent things but I can't. Could you help a bit more?

    Private Sub btnSplit_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnSplit.Click

        Dim G As Graphics = Me.PictureBox2.CreateGraphics
        Dim tileset As Bitmap
        Dim newtileset As Bitmap
        Dim iRect As Rectangle
        Dim sRect As Rectangle

        tileset = New Bitmap(PictureBox.Image)

        For x = 0 To (tileset.Width / 32)
            For y = 0 To (tileset.Height / 32)

                iRect = New Rectangle(x * 32, y * 32, 32, 32)
                sRect = New Rectangle(x * 32, y * 32, 32, 32)
                G.DrawImage(tileset, iRect, sRect, GraphicsUnit.Pixel)

                G = Graphics.FromImage(tileset)

                newtileset = tileset

            Next
        Next


    End Sub

[jmcilhinney]

call Graphics.FromImage to create a Graphics object

Dim G As Graphics = Me.PictureBox2.CreateGraphics

Do you see a discrepancy there?

[jimpie]

Do you see a discrepancy there?

I can't get it work, its now giving just a transparent png file with size 32x32

    Private Sub btnSplit_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnSplit.Click

        Dim png As Bitmap
        Dim g As Graphics
        Dim iRect As Rectangle
        Dim sRect As Rectangle

        g = PictureBox2.CreateGraphics

        'our new file
        png = New Bitmap(32, 32)

        'create graphic object
        iRect = New Rectangle(0, 0, 32, 32)
        sRect = New Rectangle(32, 32, 32, 32)
        g.DrawImage(PictureBox.Image, iRect, sRect, GraphicsUnit.Pixel)

        g = Graphics.FromImage(png)

        png.Save("test.png", ImageFormat.Png)

    End Sub

[Ram2Curious]

Take a look at this example.

[jimpie]

Take a look at this example.

thanks