取bmp图片的宽与高
// Width and height of a picture inside a BMP file
int job
blob b
ulong width, height
job = FileOpen( "filename.bmp", StreamMode!, Read! )
FileRead( job, b )
width = Long( Integer( BlobMid( b, 19, 2 ) ), &
Integer( BlobMid( b, 21, 2) ) )
height = Long( Integer( BlobMid( b, 23, 2 ) ), &
Integer( BlobMid( b, 25, 2) ) )
FileClose( job )
得到极大的随机数
//////////////////////////////////////////////////////////////////////////
// Function: f_BigRand
//
// Description:
// This function uses 2 calls to Rand to generate Random numbers for large
// ranges. It breaks the range into blocks of 32767 (max range for
// RAND function)
// The limit of the function is 32767 blocks of 32767.
// It calls RAND to first determine which block, then calls RAND again to
// determine the number in the
// selected block. To ensure even probability over the range where
// there are multiple blocks,
// the same sub range is used for each block.
//
// Argument al_range
// The upper limit of the range of random numbers you want returned.
// The lower limit is always 1. The maximum value for the argument is
// 1,073,676,289 or 32767*32767.
//
// Returns
// A random number in the range 1 to al_range inclusive.
// Or 0 if max range exceeded.
//
// Author: David Dennis
//////////////////////////////////////////////////////////////////////////
//
// Revision History
//
// -----------------------------------------------------------------------
// VERSION CHANGE ID WHO WHEN WHAT/WHY
// -----------------------------------------------------------------------
// 6.30 8/4/00 Initial version.
//////////////////////////////////////////////////////////////////////////
Long ll_Offset, ll_Return
Integer li_Range, li_Blocks
// Block size is set to 32767 as this is the maximum range
// the RAND function can handle
Integer li_BlockSize = 32767
IF al_range > 1073676289 THEN
//Range is too big
Return 0
END IF
//Determine The number of blocks
li_Blocks = Truncate(al_range/li_BlockSize,0)
//Add an extra block to accommodate any remainder
IF Mod(al_range, li_BlockSize) > 0 THEN
li_Blocks = li_Blocks + 1
END IF
// Improve efficiency for ranges less than Block Size
// where there is only one block
IF al_range < li_BlockSize THEN
li_Range = al_range
ELSE
li_Range = li_BlockSize
END IF
ll_Return = 0
// Loop until the value is in range.
// If the value is not in range, calculate the
// Offset again to ensure even probability
DO UNTIL (ll_Return > 0) And (ll_Return <= al_Range)
// Calculate a Random Offset using the number
// of blocks as the range.
// Offsets will range from [0 to
