AUTOTRIMDLGPARAMS

typedef struct _AUTOTRIMDLGPARAMS
{
   L_UINT uStructSize;
   pBITMAPHANDLE pBitmap;
   L_INT nThreshold;
   L_UINT32 uDlgFlags;
   LTCOMMDLGHELPCB pfnHelpCallback;
   L_VOID *pHelpCallBackUserData;
} AUTOTRIMDLGPARAMS,* LPAUTOTRIMDLGPARAMS;

The AUTOTRIMDLGPARAMS structure provides information used to initialize the dialog box created by the L_DlgAutoTrim function. After the user closes the dialog box, this structure is updated with information about the user's selections.

Member

Description

uStructSize

Size of this structure, in bytes. Use the sizeof operator to calculate this value.

pBitmap

Pointer to the bitmap handle that references the bitmap used for preview or processing.

nThreshold

Delta value for detecting blank space. Notice that the dialog dynamically calculates the range of threshold values that are applicable to your bitmap, once the dialog starts using the bitmap passed in the pBitmap parameter. If you dont provide a valid bitmap, or NULL is passed in the pBitmap parameter, the range of values is between 0 and 244.

uDlgFlags

User interface flags for this dialog, which determine the layout and action of the dialog. Possible values are:

 

Value

Meaning

 

DLG_AUTOTRIM_AUTOPROCESS

[0x00000001] process the image on OK. The pBitmap member of this structure should contain a valid bitmap.

 

DLG_AUTOTRIM_SHOW_CONTEXTHELP

[0x00000002] dialog should contain a context sensitive help icon.

 

DLG_AUTOTRIM_SHOW_PREVIEW

[0x00000004] show a preview of the image in the dialog. The pBitmap member of this structure should contain a valid bitmap.

 

DLG_AUTOTRIM_SHOW_APPLY

[0x00000080] Show the Apply button in the dialog. The dialog will not apply any effect unless the user presses the Apply button.

pfnHelpCallback

Pointer to an optional help callback function. If you do not wish to provide help to this dialog, use NULL as the value of this parameter. To provide help to this dialog, use the function pointer as the value of this parameter. The callback function must adhere to the prototype described in LTCOMMDLGHELPCB.

pHelpCallBackUserData

Void pointer that you can use to pass one or more additional parameters that the callback function needs. To use this feature, assign a value to a variable or create a structure that contains as many fields as you need. Then, in this parameter, pass the address of the variable or structure, casting it to L_VOID *. The callback function, which receives the address in its own pHelpCallBackUserData parameter, can cast it to a pointer of the appropriate data type to access your variable or structure. If the additional parameters are not needed, you can pass NULL in this parameter.