PAINTXFORM

typedef struct _PAINTXFORM 
{ 
   L_INT nZoom; 
   L_INT nXOffset; 
   L_INT nYOffset; 
} PAINTXFORM, * pPAINTXFORM; 

The PAINTXFORM structure provides data for translating from the external coordinates, such as mouse position, to the device context (DC) or bitmap coordinates.

Members

nZoom

The zooming factor that will be used by the toolkit to scale the user input. Valid values are between 1 and 10000, For example:

nXOffset

The X offset of the external representation of the DC or Bitmap.

nYOffset

The Y offset of the external representation of the DC or Bitmap.

Comments

When assigning an external representation to the toolkit, every point (Xa, Ya) in the an external representation is transformed by the toolkit to the point (Xc, Yc) by using the following steps:

1. Add offsets:

      Xb = Xa + nXOffset   
      Yb = Ya + nYOffset 

2. Multiply by scalars:

      Xc = MulDiv (Xb, nZoom, 100 ) ;   
      Yc = MulDiv ( Yb, nZoom, 100 ) ; 

pPAINTXFORM is a pointer to a PAINTXFORM structure.