'''' This code is part of Document Solutions for Imaging demos.'' Copyright (c) MESCIUS inc. All rights reserved.''Imports System.IOImports System.DrawingImports GrapeCity.Documents.DrawingImports GrapeCity.Documents.TextImports GrapeCity.Documents.ImagingImports GCTEXT = GrapeCity.Documents.Text
'' This sample shows how to enlarge a loaded image'' using different interpolation modes.Public Class EnlargeImage    Function GenerateImage(        ByVal pixelSize As Size,        ByVal dpi As Single,        ByVal opaque As Boolean,        Optional ByVal sampleParams As String() = Nothing) As GcBitmap
        Dim origImagePath = Path.Combine("Resources", "Stock", "woman-window-small.jpg")        '' Create and clear the target bitmap:        Dim targetBmp = New GcBitmap(pixelSize.Width, pixelSize.Height, True, dpi, dpi)        targetBmp.Clear(Color.Transparent)
        Const fontSize = 16, fpad = 4, xpad = 4, ypad = 3        Dim tf = New TextFormat With        {            .Font = GCTEXT.Font.FromFile(Path.Combine("Resources", "Fonts", "FreeSerif.ttf")),            .FontSize = fontSize        }        Using origBmp = New GcBitmap()            Using stm = New FileStream(origImagePath, FileMode.Open, FileAccess.Read, FileShare.Read, 4096, FileOptions.RandomAccess)                origBmp.Load(stm)            End Using
            '' Draw the original with the original size:            targetBmp.BitBlt(origBmp, 0, 0)            Using g = targetBmp.CreateGraphics(Nothing)                g.DrawString($"⟵ Original image ({origBmp.Width} by {origBmp.Height} pixels)", tf, New PointF(origBmp.Width + fpad, fpad))            End Using            Dim dy = origBmp.Height + ypad
            '' Enlarge image so that we can have 4 enlarged tiled images preserving aspect ratio:            Dim f = Math.Min(                (targetBmp.Width - xpad) / origBmp.Width / 2,                (targetBmp.Height - ypad - dy) / origBmp.Height / 2)            Dim twidth = (origBmp.Width * f)            Dim theight = (origBmp.Height * f)
            ''            Dim drawCaption As Action(Of String, Single, Single) =            Sub(caption, x, y)                Using g = targetBmp.CreateGraphics(Nothing)                    g.DrawString(caption, tf, New RectangleF(x + fpad, y + theight - fontSize - fpad * 2, twidth - fpad * 2, fontSize + fpad * 2))                End Using            End Sub
            '' Enlarge and draw 4 copies using the 4 available interpolation modes:            Using bmp = origBmp.Resize(twidth, theight, InterpolationMode.NearestNeighbor)                targetBmp.BitBlt(bmp, 0, dy)            End Using            drawCaption("InterpolationMode.NearestNeighbor", 0, dy)
            Using bmp = origBmp.Resize(twidth, theight, InterpolationMode.Linear)                targetBmp.BitBlt(bmp, 0, dy + theight + ypad)            End Using            drawCaption("InterpolationMode.Linear", 0, dy + theight + ypad)
            Using bmp = origBmp.Resize(twidth, theight, InterpolationMode.Cubic)                targetBmp.BitBlt(bmp, twidth + xpad, dy)            End Using            drawCaption("InterpolationMode.Cubic", twidth + xpad, dy)
            Using bmp = origBmp.Resize(twidth, theight, InterpolationMode.Downscale)                targetBmp.BitBlt(bmp, twidth + xpad, dy + theight + ypad)            End Using            drawCaption("InterpolationMode.Downscale", twidth + xpad, dy + theight + ypad)            ''        End Using        Return targetBmp    End FunctionEnd Class