Date: 02-16-2022
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created by gbSnippets
'There are a several API discussed in these BMP Tutor snippets. This page
'provides a diagram of how many of the API tie together, shows the data
'structure for bitmap file, shows the data structures for the two types
'of bitmaps bitmaps (DDB and DIB), lists members of all the data structures
'and shows the arguments for each of list API.
'When you've gone through all of the BMP Tutor snippets, this page should
'serve as a reference point to help tie together all of the elements needed
'to work with bitmaps.
CreateCompatibleDC()
|
V
*-----------*
*.bmp --> LoadImage() --> DDB --> SelectObject() --> | |
*.bmp --> LoadImage() --> DIBSection --> SelectObject() --> | |
| |
resource --> LoadImage() --> DDB --> SelectObject() --> | |
resource --> LoadImage() --> DIBSection --> SelectObject() --> | Device |
| Context |
scratch --> CreateCompatibleBitmap() --> DDB --> SelectObject() --> | |
| |
scratch --> CreateDIBSection() --> DIBSection --> SelectOjbect() --> | |
| |
*-----------*
|
|
-------Data Structures ------------- |
DDB Bitmap |
|
DIB BITMAPINFO |
--> BITMAPINFOHEADEr |
--> ColorArray |
|
File BITMAPFILEHEADER V
BITMAPINFOHEADER GetObject()
ColorDATAArray |
*------+-------*
DIBSECTION BITMAPFILEHEADER | |
ColorDATAArray V V
DDB DIBSection
|
V
GetDIBits()
|
V
DIBSection
'Bitmap Data Structures
'This list shows the data structures that make up the various bitmap types. The members
'of each data structure are also shown.
File DDB DIB
---------- ------------- --------------
BITMAPFILEHEADER Bitmap BITMAPINFO
BitmapInfoHeader --> BitmapInfoHeader
ColorBytes --> RGBQuad
BITMAPFILEHEADER Bitmap RGBQuad
bfType AS WORD bmType As Long rgbBlue As Byte
bfSize AS DWord bmWidth As Long rgbGreen As Byte
bfReserved1 AS WORD bmHeight As Long rgbRed As Byte
bfReserved2 AS WORD bmWidthBytes As Long rgbReserved As Byte
bfOffBits AS DWord bmPlanes As Word
bmBits As Byte PTR
BITMAPINFOHEADER BITMAPINFOHEADER
biSize As DWord biSize As DWord
biWidth As Long biWidth As Long
biHeight As Long biHeight As Long
biPlanes As Word biPlanes As Word
biBitCount As Word biBitCount As Word
biCompression As DWord biCompression As DWord
biSizeImage AS DWord biSizeImage AS DWord
biXPelsPerMeter As Long biXPelsPerMeter As Long
biYPelsPerMeter As Long biYPelsPerMeter As Long
biClrUsed AS DWord biClrUsed AS DWord
biClrImportant AS DWord biClrImportant AS DWord
CreateBitmap GetDIBits (Create DIB From DDB)
CreateBitmapIndirect CreateDIBSection (Create DIB From scratch)
CreateCompatibleBitmap SetDIBitsToDevice (Use DIB to Set Pixels On Display)
CreateDiscardableBitmap StretchBibits (Use DIB to Set Pixels On Display
CreateDIBitmap (Create DDB From DIB)
'Note: ColorBytes for a File are organized as BGR, word aligned, and (usually) upside down
'rows (scanlines). The bytes are simply stored in the file sequentially and may be read
'in however the programmers choses, such as single-dimension or two-dimensional arrays.
'A two-dimensional array is generally considered the most convenient to use on coding.
'Note: You can manually create the data structures and image color data arrays to create
'a bitmap file and a DIB. A DDB cannot be manually created because the image color data
'is stored in the device for which the color format is not available.
'These API, from the above diagram, are frequently used when working with bitmap.
'Here are their arguments.
GetDIBits 'hDC, hBMP, uStartScan, cScanLines, lpvBits, lpbi, uUsage
CreateDIBSection 'hDC, pbmi, iUsage, ppvBits, hSection, dwOffset
SetDIBitsToDevice 'hDC, xDest, yDest, dwWidth, dwHeight, xSrc, ySrc, uStartScan, cScanLines, lpvBits, lpbmi, fuColorUse
StretchDIBits 'hDc, xDest, yDest, nDestWidth, nDestHeight, xSrc, ySrc, nSrcWidth, nSrcHeight, lpvBits, lpBitsInfo, iUsage, dwRop
CreateBitmap 'nWidth, nHeight, cPlanes, cBitsPerPel, lpvBits
CreateBitmapIndirect 'lpbm
CreateCompatibleBitmap 'hDC, nWidth, nHeight
CreateDiscardableBitmap 'hDC, nWidth, nHeight
CreateDIBitmap 'hDC, lpbmih, fdwInit, lpbInit, lpbmi, fuUsage
'These bitmap API, not in the diagram, are used less frequently. Here are their arguments.
SetDIBits 'hDC, hBMP, uStartScan, cScanLines, lpvBits, lpbi, fuColorUse
GetBitmapBits 'hBMP, cBuffer, lpvBits
SetBitmapBits 'hBMP, cBytes, lpBits
'These API are listed at MSDN under other topics, but are useful in working with bitmaps.
LoadImage 'hInst, lpszName, uType, cxDesired, cyDesired, fuLoad
GetObject 'hgdiObj, cbBuffer, lpvObject
SelectObject 'hDC, hgdiObj
GetDC 'hWnd
GetDCEx 'hWnd, hrgnClip, flags
GetCompatibleDC 'hDC
CreateDC 'lpszDriver, lpszDevice, lpszOutput, lpInitData
DeleteObject 'hObject
DeleteDC 'hDC
ReleaseDC 'hWnd, hDC
'gbs_00444
'Date: 03-10-2012
http://www.garybeene.com/sw/gbsnippets.htm