The LineDDA function determines which pixels should be highlighted for a line defined by the specified starting and ending points.
BOOL LineDDA(
| int nXStart, | // x-coordinate of line's starting point |
| int nYStart, | // y-coordinate of line's starting point |
| int nXEnd, | // x-coordinate of line's ending point |
| int nYEnd, | // y-coordinate of line's ending point |
| LINEDDAPROC lpLineFunc, | // address of application-defined callback function |
| LPARAM lpData | // address of application-defined data |
| ); |
Parameters
nXStart
Specifies the x-coordinate of the line's starting point.
nYStart
Specifies the y-coordinate of the line's starting point.
nXEnd
Specifies the x-coordinate of the line's ending point.
nYEnd
Specifies the y-coordinate of the line's ending point.
lpLineFunc
Specifies the address of an application-defined callback function. For more information, see the LineDDAProc callback function.
lpData
Points to the application-defined data.
Return Values
If the function succeeds, the return value is nonzero.
If the function fails, the return value is zero.
Remarks
The LineDDA function passes the coordinates for each point along the line, except for the line's ending point, to the application-defined callback function. In addition to passing the coordinates of a point, this function passes any existing application-defined data.
The coordinates passed to the callback function match pixels on a video display only if the default transformations and mapping modes are used.
See Also