References ▼
#include "Ltwrappr.h"
L_INT LContainer::SetOffset (nXOffset, nYOffset, nZOffset = 0)
Sets the container coordinates offset values.
The offset in the X direction of the external representation.
The offset in the Y direction of the external representation.
The offset in the Z direction of the external representation. Default value is 0.
| Value | Meaning |
|---|---|
| SUCCESS | The function was successful. |
| < 1 | An error occurred. Refer to Return Codes. |
The user should set the offset every time the window that owns the container is scrolled.
When assigning an external representation to the container every point (Xa, Ya) in the an external representation is transformed by the container to the point (Xc, Yc) by using the following steps:
Add offsets
Xb = Xa + nXOffset
Multiply by scalars
Xc = (Xb \* nXScalarNum) / nXScalarDen
Yc = (Yb \* nYScalarNum) / nYScalarDen
Yb = Ya + nYOffset
The default offsets values are nXOffset = 0, nYOffset = 0 and nZOffset = 0.
Required DLLs and Libraries
This will show to modify the container coordinates offset values to reflect the changes in the window offset.
The example assumes that there is an already initialized toolbar handle.
LContainer lCont ;/*static*/ L_VOID OnSize(HWND hWnd,pBITMAPHANDLE pBitmap,LPRECT prcView,L_INT cx,L_INT cy,L_INT nZoom,L_INT *pnHScroll,L_INT *pnVScroll){SCROLLINFO si ;L_INT nXOffset, nYOffset ;if ( NULL != pBitmap && pBitmap->Flags.Allocated ){si.cbSize = sizeof ( SCROLLINFO ) ;si.fMask = SIF_ALL ;// vertical scroll.::GetScrollInfo ( hWnd, SB_VERT, &si ) ;si.nMin = 0 ;si.nMax = BITMAPHEIGHT ( pBitmap ) ;si.nPage = MulDiv ( cy, 100, nZoom ) ;::SetScrollInfo ( hWnd, SB_VERT, &si, TRUE ) ;::GetScrollInfo ( hWnd, SB_VERT, &si ) ;*pnVScroll = si.nPos ;// horizontal scroll::GetScrollInfo ( hWnd, SB_HORZ, &si ) ;si.nMin = 0 ;si.nMax = BITMAPWIDTH ( pBitmap ) ;si.nPage = MulDiv ( cx, 100, nZoom ) ;::SetScrollInfo ( hWnd, SB_HORZ, &si, TRUE ) ;::GetScrollInfo ( hWnd, SB_HORZ, &si ) ;*pnHScroll = si.nPos ;}else{si.cbSize = sizeof ( SCROLLINFO ) ;si.fMask = SIF_RANGE ;si.nMin = 0 ;si.nMax = 0 ;::SetScrollInfo ( hWnd, SB_VERT, &si, TRUE ) ;::SetScrollInfo ( hWnd, SB_HORZ, &si, TRUE ) ;*pnHScroll = 0 ;*pnVScroll = 0 ;}// set the painting rectangel.SetRect ( prcView, 0, 0, BITMAPWIDTH ( pBitmap ), BITMAPHEIGHT ( pBitmap ) ) ;if ( nZoom < 100 ){nXOffset = MulDiv ( *pnHScroll, 100, nZoom ) ;nYOffset = MulDiv ( *pnVScroll, 100, nZoom ) ;}else{nXOffset = *pnHScroll ;nYOffset = *pnVScroll ;}OffsetRect ( prcView, - nXOffset, - nYOffset ) ;prcView->left = MulDiv ( prcView->left, nZoom, 100 ) ;prcView->top = MulDiv ( prcView->top, nZoom, 100 ) ;prcView->right = MulDiv ( prcView->right, nZoom, 100 ) ;prcView->bottom = MulDiv ( prcView->bottom, nZoom, 100 ) ;lCont.SetOffset ( - prcView->top, 0 ) ;}