Category : C Source Code
Archive   : WNSRC173.ZIP
Filename : SELECT.C

/****************************************************************************

PROGRAM: Select.c

PURPOSE: Contains library routines for selecting a region

FUNCTIONS:

StartSelection(HWND, POINT, LPRECT, int) - begin selection area
UpdateSelection(HWND, POINT, LPRECT, int) - update selection area
EndSelection(POINT, LPRECT) - end selection area
ClearSelection(HWND, LPRECT, int) - clear selection area

*******************************************************************************/

#include "windows.h"
#include "select.h"

extern BOOL bTrack, bMove, bMoving;

/****************************************************************************

FUNCTION: StartSelection(HWND, POINT, LPRECT, int)

PURPOSE: Begin selection of region

****************************************************************************/


POINT Center, DragPoint, ZoomDim;

void FAR PASCAL StartSelection(hWnd, ptCurrent, lpSelectRect, fFlags)
HWND hWnd;
POINT ptCurrent;
LPRECT lpSelectRect;
int fFlags;
{
if (lpSelectRect->left != lpSelectRect->right ||
lpSelectRect->top != lpSelectRect->bottom)
ClearSelection(hWnd, lpSelectRect, fFlags);

lpSelectRect->right = ptCurrent.x;
lpSelectRect->bottom = ptCurrent.y;

/* If you are extending the box, then invert the current rectangle */

if ((fFlags & SL_SPECIAL) == SL_EXTEND)
ClearSelection(hWnd, lpSelectRect, fFlags);

/* Otherwise, set origin to current location */

else {
lpSelectRect->left = ptCurrent.x;
lpSelectRect->top = ptCurrent.y;
Center = ptCurrent;
}
SetCapture(hWnd);
}

extern int xdots, ydots;

/****************************************************************************

FUNCTION: UpdateSelection(HWND, POINT, LPRECT, int) - update selection area

PURPOSE: Update selection

****************************************************************************/

void FAR PASCAL UpdateSelection(hWnd, ptCurrent, lpSelectRect, fFlags)
HWND hWnd;
POINT ptCurrent;
LPRECT lpSelectRect;
int fFlags;
{
HDC hDC;
short OldROP;
POINT NewDim, NewPoint;
unsigned ScaledY;

hDC = GetDC(hWnd);

switch (fFlags & SL_TYPE) {

case SL_BOX:
OldROP = SetROP2(hDC, R2_NOTXORPEN);
MoveTo(hDC, lpSelectRect->left, lpSelectRect->top);
LineTo(hDC, lpSelectRect->right, lpSelectRect->top);
LineTo(hDC, lpSelectRect->right, lpSelectRect->bottom);
LineTo(hDC, lpSelectRect->left, lpSelectRect->bottom);
LineTo(hDC, lpSelectRect->left, lpSelectRect->top);

LineTo(hDC, ptCurrent.x, lpSelectRect->top);
LineTo(hDC, ptCurrent.x, ptCurrent.y);
LineTo(hDC, lpSelectRect->left, ptCurrent.y);
LineTo(hDC, lpSelectRect->left, lpSelectRect->top);
SetROP2(hDC, OldROP);
break;

case SL_BLOCK:
PatBlt(hDC,
lpSelectRect->left,
lpSelectRect->bottom,
lpSelectRect->right - lpSelectRect->left,
ptCurrent.y - lpSelectRect->bottom,
DSTINVERT);
PatBlt(hDC,
lpSelectRect->right,
lpSelectRect->top,
ptCurrent.x - lpSelectRect->right,
ptCurrent.y - lpSelectRect->top,
DSTINVERT);
break;

/* MCP 6-3-92 */
case (SL_ZOOM):
OldROP = SetROP2(hDC, R2_NOTXORPEN);
MoveTo(hDC, lpSelectRect->left, lpSelectRect->top);
LineTo(hDC, lpSelectRect->right, lpSelectRect->top);
LineTo(hDC, lpSelectRect->right, lpSelectRect->bottom);
LineTo(hDC, lpSelectRect->left, lpSelectRect->bottom);
LineTo(hDC, lpSelectRect->left, lpSelectRect->top);

if(bTrack)
{
NewPoint = ptCurrent;

NewDim.x = Center.x - NewPoint.x;
if(NewDim.x < 0)
NewDim.x = -NewDim.x;

NewDim.y = Center.y - NewPoint.y;
if(NewDim.y < 0)
NewDim.y = -NewDim.y;

ScaledY = (unsigned)(((long)NewDim.y) * xdots / ydots);
if(NewDim.x < ScaledY)
NewDim.x = ScaledY;
else
NewDim.y = (unsigned)(((long)NewDim.x) * ydots / xdots);

if(NewDim.x < 2)
NewDim.x = 2;
if(NewDim.y < 2)
NewDim.y = 2;

ZoomDim = NewDim;
}
else if(bMoving)
{
Center.x += ptCurrent.x - DragPoint.x;
Center.y += ptCurrent.y - DragPoint.y;
DragPoint = ptCurrent;
}

if (bTrack || bMoving) {
lpSelectRect->left = Center.x - ZoomDim.x;
lpSelectRect->right = Center.x + ZoomDim.x;
lpSelectRect->bottom = Center.y + ZoomDim.y;
lpSelectRect->top = Center.y - ZoomDim.y;

MoveTo(hDC, lpSelectRect->left, lpSelectRect->top);
LineTo(hDC, lpSelectRect->right, lpSelectRect->top);
LineTo(hDC, lpSelectRect->right, lpSelectRect->bottom);
LineTo(hDC, lpSelectRect->left, lpSelectRect->bottom);
LineTo(hDC, lpSelectRect->left, lpSelectRect->top);
}

SetROP2(hDC, OldROP);
ReleaseDC(hWnd, hDC);
return;
}
lpSelectRect->right = ptCurrent.x;
lpSelectRect->bottom = ptCurrent.y;
ReleaseDC(hWnd, hDC);
}

/****************************************************************************

FUNCTION: EndSelection(POINT, LPRECT)

PURPOSE: End selection of region, release capture of mouse movement

****************************************************************************/

void FAR PASCAL EndSelection(ptCurrent, lpSelectRect)
POINT ptCurrent;
LPRECT lpSelectRect;
{
if(!bMove)
{
lpSelectRect->right = ptCurrent.x;
lpSelectRect->bottom = ptCurrent.y;
}
ReleaseCapture();
}

/****************************************************************************

FUNCTION: ClearSelection(HWND, LPRECT, int) - clear selection area

PURPOSE: Clear the current selection

****************************************************************************/

void FAR PASCAL ClearSelection(hWnd, lpSelectRect, fFlags)
HWND hWnd;
LPRECT lpSelectRect;
int fFlags;
{
HDC hDC;
short OldROP;

hDC = GetDC(hWnd);
switch (fFlags & SL_TYPE) {

/* MCP 6-3-92 */
case (SL_ZOOM):
case SL_BOX:
OldROP = SetROP2(hDC, R2_NOTXORPEN);
MoveTo(hDC, lpSelectRect->left, lpSelectRect->top);
LineTo(hDC, lpSelectRect->right, lpSelectRect->top);
LineTo(hDC, lpSelectRect->right, lpSelectRect->bottom);
LineTo(hDC, lpSelectRect->left, lpSelectRect->bottom);
LineTo(hDC, lpSelectRect->left, lpSelectRect->top);
SetROP2(hDC, OldROP);
break;

case SL_BLOCK:
PatBlt(hDC,
lpSelectRect->left,
lpSelectRect->top,
lpSelectRect->right - lpSelectRect->left,
lpSelectRect->bottom - lpSelectRect->top,
DSTINVERT);
break;

}
ReleaseDC(hWnd, hDC);
}