Question on using CreateBitmapIndirect().

[Steve Hutchesson]

I have been playing with an idea of how to embed image data into a PB executable that is not stored as a resource but as BYTE data, something that is easy enough to do as a DB block and while the code I have written produces the correct "GetLastError" values and the STATIC control I am trying to put it in resizes to the image size, not for love nor money can I get the image to display. This is the bare code without the byte data storage.

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    bmp.bmType       = 0
    bmp.bmWidth      = 64
    bmp.bmHeight     = 64
    bmp.bmWidthBytes = 64*3
    bmp.bmPlanes     = 1
    bmp.bmBitsPixel  = 24
    bmp.bmBits       = oldbook_bmp(0)       ' +54

    hBmp = CreateBitmapIndirect(ByVal VarPtr(bmp.bmType))


The "oldbook_bmp" is a valid pointer to the BYTE data, the structure (UDT) is a normal BITMAP structure that has been tweaked so the last member is a DWORD, not a BYTE PTR. The image is a 64 x 64 pixel 24 bit bitmap.

When I test the size of the STATIC control after the code is run it has been resized to 64 x 64 after calling,

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        SendMessage GetDlgItem(hDlg,999),%STM_SETIMAGE,%IMAGE_BITMAP,hBmp


If I load the bitmap as a resource and call it with LoadImage() everything works as expected.

Has anyone ever got CreateBitmapIndirect() to work on a 24 bit bitmap ?

[Patrice Terrier]

While the CreateBitmapIndirect function can be used to create color bitmaps, for performance reasons applications should use CreateBitmapIndirect to create monochrome bitmaps and CreateCompatibleBitmap to create color bitmaps. Whenever a color bitmap from CreateBitmapIndirect is selected into a device context, the system must ensure that the bitmap matches the format of the device context it is being selected into. Because CreateCompatibleBitmap takes a device context, it returns a bitmap that has the same format as the specified device context. Thus, subsequent calls to SelectObject are faster with a color bitmap from CreateCompatibleBitmap than with a color bitmap returned from CreateBitmapIndirect.

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[Steve Hutchesson]

Patrice,

The speed issue did not worry me, it was that it did not display even though the return values from GetLastError kept saying it succeeded.

What I am looking for is a method where I can specify the byte data for a bitmap and end up with a working bitmap handle. LoadImage will load from a file but it will not load from a memory address.

LATER : Not to worry, I foud a clean and simple way around it.