image fading in Direct Draw 7 2

[slowATthought]

I need to be able to fade an image to any color in Direct Draw. Any help is.... um.... helpful.

 

[slowATthought]

True, ESquared, I will look.

TheTuna, I like the site. I already learned how to change fonts in DD. I checked out alphablending in DD, and it told me about a vbDABL. It's a dll, and I'm going to try using it.

Strongm, because I would use GDI's alphablend, but vbDABl is sopposed to be very fast (which I like). Thanks for the suggestion, though.

Thanks, everyone, especially strongm, because you have been helping me on this for more than a week.

 

[TheTuna]

Glad to help, and reguarding Strongm, there's a reason his name shows up at the top of the forum MVP list... he's very helpful, and very knowledgable.

No Dolphins were harmed in the posting of this message... Dolphin Friendly Tuna!

Ever feel like you're banging your head against a tree? I did, so I cut down the tree.

 

[strongm]

Well, if you really think that a 3rd party DLL (that only works properly on 16-bit color images) is faster/easier than a built-in function...

 

[TheTuna]

I think it's more likely that he didn't fully read the tutorial, therefore didn't realize it only supports 16 bit color.

No Dolphins were harmed in the posting of this message... Dolphin Friendly Tuna!

Ever feel like you're banging your head against a tree? I did, so I cut down the tree.

 

[slowATthought]

Uh... I actually didn't. I still haven't gotten it to download. I feel stupid. I hadn't checked back on this thread.

Strongm, if you read this, I'm all ears about the GDI AlphaBlend function.

 

[strongm]

Um...if I get the chance...

Basically, I'm only likely to be posting short answers for the next couple of weeks or so as I get used to being a new dad...

 

[TheTuna]

Way to go Strongm!

No Dolphins were harmed in the posting of this message... Dolphin Friendly Tuna!

Ever feel like you're banging your head against a tree? I did, so I cut down the tree.

 

[strongm]

Option Explicit

Private Declare Sub Sleep Lib "kernel32" (ByVal dwMilliseconds As Long)

Private Type BLENDFUNCTION
  BlendOp As Byte
  BlendFlags As Byte
  SourceConstantAlpha As Byte
  AlphaFormat As Byte
End Type
' BlendOp:
Private Const AC_SRC_OVER = &H0
' AlphaFormat:
Private Const AC_SRC_ALPHA = &H1

Private Declare Sub CopyMemory Lib "kernel32" Alias "RtlMoveMemory" ( _
    lpvDest As Any, lpvSource As Any, ByVal cbCopy As Long)

Private Declare Function AlphaBlend Lib "MSIMG32.dll" ( _
  ByVal hdcDest As Long, _
  ByVal nXOriginDest As Long, _
  ByVal nYOriginDest As Long, _
  ByVal nWidthDest As Long, _
  ByVal nHeightDest As Long, _
  ByVal hdcSrc As Long, _
  ByVal nXOriginSrc As Long, _
  ByVal nYOriginSrc As Long, _
  ByVal nWidthSrc As Long, _
  ByVal nHeightSrc As Long, _
  ByVal lBlendFunction As Long _
) As Long

Private Sub Command1_Click()
    Dim lBlend As Long
   Dim bf As BLENDFUNCTION
   Dim alpha As Long

   ' Draw the first picture:
   bf.BlendOp = AC_SRC_OVER
   bf.BlendFlags = 0
   bf.SourceConstantAlpha = 128
   bf.AlphaFormat = 0
   CopyMemory lBlend, bf, 4
   AlphaBlend Me.hDC, 0, 0, Picture1.ScaleWidth, Picture1.ScaleHeight, Picture1.hDC, 0, 0, Picture1.ScaleWidth, Picture1.ScaleHeight, lBlend

    ' Make sure picture2 is same size as picture 1
    Picture2.Width = Picture1.Width
    Picture2.Height = Picture1.Height
    
    ' OK now blend towards the colour held in Picture 2
    For alpha = 0 To 95
        bf.SourceConstantAlpha = alpha
        CopyMemory lBlend, bf, 4
        AlphaBlend Me.hDC, 0, 0, Picture1.ScaleWidth, Picture1.ScaleHeight, Picture2.hDC, 0, 0, Picture2.ScaleWidth, Picture2.ScaleHeight, lBlend
        Sleep 100
    Next
End Sub

Private Sub Form_Load()

    Form1.Picture = Picture1.Picture
    Picture1.AutoSize = True
    
    Picture2.BackColor = RGB(255, 0, 0)
    
    Picture1.AutoRedraw = True
    Picture1.ScaleMode = vbPixels
    Picture2.ScaleMode = vbPixels
    Picture2.AutoRedraw = True
End Sub

 

[strongm]

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