MouSetScaleFact

This call assigns to the current mouse device driver a new pair of 1-word scaling factors.

 MouSetScaleFact (ScaleStruct, DeviceHandle)

• ScaleStruct (PSCALEFACT) - input : Address of the control block structure that contains the current row and column coordinate scaling factors.
• DeviceHandle (HMOU) - input : Handle of the mouse device from a previous MouOpen.

rc (USHORT) - return:Return code descriptions are:

• 0 NO_ERROR
• 385 ERROR_MOUSE_NO_DEVICE
• 387 ERROR_MOUSE_INV_PARMS
• 466 ERROR_MOU_DETACHED
• 501 ERROR_MOUSE_NO_CONSOLE
• 505 ERROR_MOU_EXTENDED_SG

MouSetScaleFact sets the mickey-to-pixel ratio for mouse motion. The row scale and column scale ratios specify a number of mickeys for each 8 pixels. The default value for the row scale is 16 mickeys for each 8 pixels. The default value for the column scale is 8 mickeys to 8 pixels.

The number of pixels moved does not have to correspond 1-to-1 with the number of mickeys the mouse moves. The scaling factor defines a sensitivity for the mouse that is a ratio of the number of mickeys required to move the cursor 8 pixels on the screen. The sensitivity determines at what rate the cursor moves on the screen.

typedef struct _SCALEFACT { /* mousc */
  USHORT rowScale;          /* row scaling factor */
  USHORT colScale;          /* column coordinate scaling factor */
} SCALEFACT;
 
#define INCL_MOU
 
USHORT  rc = MouSetScaleFact(ScaleStruct, DeviceHandle);
 
PSCALEFACT ScaleStruct;   /* 2-word structure */
HMOU       DeviceHandle;  /* Mouse device handle */
 
USHORT     rc;            /* return code */

SCALEFACT struc
  mousc_rowScale  dw  ? ;row scaling factor
  mousc_colScale  dw  ? ;column coordinate scaling factor
SCALEFACT ends
 
EXTRN  MouSetScaleFact:FAR
INCL_MOU            EQU 1
 
PUSH@  OTHER   ScaleStruct   ;2-word structure
PUSH   WORD    DeviceHandle  ;Mouse device handle
CALL   MouSetScaleFact
 
Returns WORD