L_PutBitmapRowCol
#include "l_bitmap.h"
L_LTKRN_API L_SSIZE_T L_PutBitmapRowCol(pBitmap, pBuffer, nRow, nCol, uBytes)
pBITMAPHANDLE pBitmap; |
/* pointer to the bitmap handle */ |
L_UCHAR* pBuffer; |
/* pointer to the source buffer */ |
L_INT nRow; |
/* number of the row to update */ |
L_INT nCol; |
/* column offset within the row to update */ |
L_SIZE_T uBytes; |
/* number of bytes to update */ |
Copies data from a buffer to a bitmap, with an offset to the bitmap. The buffer to which pBuffer points contains uncompressed data.
Parameter |
Description |
pBitmap |
Pointer to the bitmap handle referencing the bitmap to put data into. |
pBuffer |
Pointer to the buffer containing the image data. |
nRow |
The number of the row to update. The first row is 0, and the last row is 1 less than the bitmap height. |
nCol |
The column offset within the row to update. The first column offset is 0, and the last column offset is 1 less than the bitmap width. |
uBytes |
The number of bytes to update. Consider the bits per pixel, and avoid specifying a number that goes past the end of the row. |
|
For a 1-bit bitmap, each byte represents 8 pixels. For a 4-bit bitmap, each byte represents 2 pixels. For an 8-bit bitmap, each byte represents 1 pixel. For a 16-bit bitmap, every 2 bytes represents one pixel. For 24-bit images, every three bytes represents one pixel. For a 32-bit bitmap, every four bytes represents one pixel. For a 48-bit bitmap, every six bytes represents one pixel. For a 64-bit bitmap, every eight bytes represents one pixel. |
Returns
>=1 |
The number of bytes put. |
< 1 |
An error occurred. Refer to Return Codes. |
Comments
By using this low-level function to update any part of a row, you can write a procedure that updates a single pixel or a rectangular area within the bitmap.
This function accepts an offset parameter (nCol) in pixels and a length (uBytes) in bytes. Therefore, you must consider the bits per pixel of the bitmap when specifying these parameters. The following table describes the rules:
Bits Per |
Column Offset (in Pixels) |
Bytes to Update |
1 |
Must be a multiple of 8 (such as 0, 8, or 16). |
Should not go past the end of the row. Consider that there are 8 pixels per byte. |
4 |
Must be an even number (such as 0, 2, or 4). |
Should not go past the end of the row. Consider that there are 2 pixels per byte. |
8 |
Can be any column within the bitmap. |
Should not go past the end of the row. Consider that there is 1 pixel per byte. |
16 |
Can be any column within the bitmap. |
Must be a multiple of 2 (such as 2, 4, or 6), because there are 2 bytes per pixel. Also, it should not go past the end of the row. |
24 |
Can be any column within the bitmap. |
Must be a multiple of 3 (such as 3, 6, or 9), because there are 3 bytes per pixel. Also, it should not go past the end of the row. |
32 |
Can be any column within the bitmap. |
Must be a multiple of 4 (such as 4, 8, or 12), because there are 4 bytes per pixel. Also, it should not go past the end of the row. |
The bitmap memory must be locked when you use this function. Normally, you can call L_AccessBitmap to lock the memory before starting an operation that uses this function, then call L_ReleaseBitmap when the operation is finished.
Color order of the target bitmap is determined by the Order field in the bitmap handle. This value can be ORDER_RGB, ORDER_BGR, ORDER_GRAY or ORDER_ROMM.
Required DLLs and Libraries
LTKRN For a listing of the exact DLLs and Libraries needed, based on the toolkit version, refer to Files To Be Included With Your Application. |
Platforms
Windows 2000 / XP/Vista, Windows CE.
See Also
Functions: |
L_AccessBitmap, L_ReleaseBitmap, L_ClearBitmap, L_GetBitmapRow, L_PutBitmapRow, L_GetBitmapRowCol, L_GetPixelColor, L_PutPixelColor |
Topics: |
Example
For a short example, refer to L_GetBitmapRowCol. For complete sample code, refer to the GETROW example.