I attempted to write a function (using the code you provided via method 2) so I
could get it to work from ASP.

It seems to work ok, but the transparency is still not being preserved in the
Overlaying (Render_Alpha)

I have tried almost every combination of image formats I can think of, and used
ones that already had transparencies set in their pallette as well as ones using
the alph channel, and they are ignored.

Take a look and see if you can see something that I'm doing wrong:

(I have the need to make the "white" color transparent, along with some
blending, so that's what I added the blending "alphablend" at the end)

Thanks
-Michael

Public Function Effect_OverlayPictureEx(ByRef hIMG_Destination As Variant, ByVal
hIMG_Source As Long, ByVal Left As Long, ByVal Top As Long, Optional ByVal
TransparentColor As Long = vbMagenta, Optional ByVal TransparencyLevel As Byte =
0, Optional ByVal AlphaBlend As Byte = 255) As Boolean

Dim hDevCon As Long
Dim hTempImg As Long
Dim hNewBmp As Long
Dim hOldBmp As Long
Dim hImg As Long
Dim hImg2 As Long

hImg = CLng(hIMG_Destination)
hImg2 = CLng(hIMG_Source)

Dim bOk As Boolean


If NumberIsValid(hImg) = True Then

bOk = objAIL.Convert_To32bit(hImg2, hImg2)
bOk = objAIL.Effect_SetTransparentColor(hImg2, TransparentColor,
TransparencyLevel)

If bOk = True Then

Call objAIL.IO_CreateNew(hTempImg, objAIL.Info_Width(hImg),
objAIL.Info_Height(hImg), 32)




Call objAIL.Convert_ImageToBitmap(hTempImg, hNewBmp)
Call objAIL.IO_DestroyImage(hTempImg)
Call objAIL.MemoryDC_Create(hDevCon)
Call objAIL.MemoryDC_InsertBitmap(hDevCon, hNewBmp, hOldBmp)
objAIL.Render_Normal hImg, hDevCon

If AlphaBlend < 255 Then
objAIL.Render_Blend hImg2, hDevCon, Left, Top, AlphaBlend
Else
objAIL.Render_Alpha hImg2, hDevCon, Left, Top
End If


Call objAIL.MemoryDC_InsertBitmap(hDevCon, hOldBmp, hNewBmp)
Call objAIL.MemoryDC_Destroy(hDevCon): hOldBmp = 0
Call objAIL.Convert_BitmapToImage(hNewBmp, hTempImg)
Call objAIL.IO_DestroyBitmap(hNewBmp)


hIMG_Destination = hTempImg
Effect_OverlayPictureEx = True



Else
Effect_OverlayPictureEx = False
End If


End If




End Function

----- Original Message -----
From: Kevin Wilson <kevinwilson1997@...>
Date: Tuesday, April 17, 2007 11:32 am
Subject: [AIL_Development] Re: Effect_OverlayPicture
To: AIL_Development@yahoogroups.com


> There's 2 ways to do it. The first is to render directly to a Form /
> PictureBox / Printer / PropertyBox like this:
>
> ---------------------------------------------
> Dim objAIL As cAdvancedImagery
> Dim hImg As Long
> Dim hImg2 As Long
>
> ' Initialize AIL
> Set objAIL = New cAdvancedImagery
> ' Load the background image
> Call objAIL.IO_LoadImage("c:\test.bmp", hImg)
> ' Load the foreground transparent image
> Call objAIL.IO_LoadImage("c:\test111.bmp", hImg2)
> ' Convert the color WHITE to transparent on the foreground image
> Call objAIL.Effect_SetTransparentColor(hImg2, vbWhite, 0, True)
>
> ' Make the form visible
> Me.Visible = True
> Me.AutoRedraw = True
> ' Render the background image normally
> objAIL.Render_Normal hImg, Me.hDC
> Me.Refresh
> ' Render the foreground image transparently
> objAIL.Render_Alpha hImg2, Me.hDC
> Me.Refresh
>
> ' Clean up
> Call objAIL.IO_DestroyImage(hImg2)
> Call objAIL.IO_DestroyImage(hImg)
> Set objAIL = Nothing
>
> MsgBox "Success"
>
> ---------------------------------------------
> The other is to combine them in memory like this:
> ---------------------------------------------
>
> Dim objAIL As cAdvancedImagery
> Dim hDevCon As Long
> Dim hTempImg As Long
> Dim hNewBmp As Long
> Dim hOldBmp As Long
> Dim hImg As Long
> Dim hImg2 As Long
>
> ' Initialize AIL
> Set objAIL = New cAdvancedImagery
> ' Load the background image
> Call objAIL.IO_LoadImage("c:\test.bmp", hImg)
> ' Load the foreground transparent image
> Call objAIL.IO_LoadImage("c:\test111.bmp", hImg2)
> ' Convert the color WHITE to transparent on the foreground image
> Call objAIL.Effect_SetTransparentColor(hImg2, vbWhite, 0, True)
> ' Create a temporary image to create a BITMAP from
> Call objAIL.IO_CreateNew(hTempImg, objAIL.Info_Width(hImg),
> objAIL.Info_Height(hImg), 32)
> ' Convert temp image to BITMAP
> Call objAIL.Convert_ImageToBitmap(hTempImg, hNewBmp)
> ' Clean up temp image
> Call objAIL.IO_DestroyImage(hTempImg)
> ' Create a memory-based Device Context (DC)
> Call objAIL.MemoryDC_Create(hDevCon)
> ' Insert the bitmap into the memory DC (this sets the
> width/height/color depth of the memory DC)
> Call objAIL.MemoryDC_InsertBitmap(hDevCon, hNewBmp, hOldBmp)
>
> ' Render the background image normally
> objAIL.Render_Normal hImg, hDevCon
> ' Render the foreground image transparently
> objAIL.Render_Alpha hImg2, hDevCon
>
> ' Pull the modified image out of the memory DC by putting back the
> original BITMAP
> Call objAIL.MemoryDC_InsertBitmap(hDevCon, hOldBmp, hNewBmp)
> ' Clean up the DC (the old/original BITMAP is automatically destroyed
> with the DC)
> Call objAIL.MemoryDC_Destroy(hDevCon): hOldBmp = 0
> ' Convert the BITMAP back to an image
> Call objAIL.Convert_BitmapToImage(hNewBmp, hTempImg)
> ' Clean up the BITMAP
> Call objAIL.IO_DestroyBitmap(hNewBmp)
>
> ' Now that we have the image we want, display it for inspection
> Me.Visible = True
> Me.AutoRedraw = True
> objAIL.Render_Normal hTempImg, Me.hDC
> Me.Refresh
>
> ' Clean up
> Call objAIL.IO_DestroyImage(hTempImg)
> Call objAIL.IO_DestroyImage(hImg2)
> Call objAIL.IO_DestroyImage(hImg)
> Set objAIL = Nothing
>
> MsgBox "Success"
>
> ---------------------------------------------
>
> I can see that the process of overlaying images transparently is a bit
> too complex... so I'm going to be adding a new function to AIL shortly
> which will do all this for you (in a more efficient manner). I'll
> call it "Effect_OverlayPictureEx".
>
> - Kevin
>
>
>
>
>
> --- In AIL_Development@yahoogroups.com, "Michael" <michael.reep@...>
> wrote:
> >
> > I've seen the sample picstures of what AIL can do, so I know this
> > has been done, atleast some way.
> >
> > I'm trying to use Effect_OverlayPicture, and trying to put one
> image
> > on top of another with a transparent background (similar to the
> > FreeImage Composite function).
> >
> > I can load an image, and use:
> > Effect_SetTransparentColor (hImg, vbWhite)
> > and stream that back to the browser as a PNG, and everything's
> cool,
> > but when I do this:
> >
> > IO_LoadImage strPath,hImg2,IF_PNG
> > Effect_SetTransparentColor hImg2,vbWhite
> > Effect_OverlayPicture hImg, hImg2, 0, 0
> >
> > the background on the second image (hImg2) is white, no matter
> what.
> > I have even loaded transparent GIF's and transparent PNG's into
> > hImg2 and the backgrounds are still white.
> >
> > Any help is appreciated.
> > -Michael
> >
>
>
>