Sweden-Number/windows/scroll.c

172 lines
3.7 KiB
C

/*
* Scroll windows and DCs
*
* Copyright David W. Metcalfe, 1993
*
*/
static char Copyright[] = "Copyright David W. Metcalfe, 1993";
#include <stdlib.h>
#include "windows.h"
#include "gdi.h"
static int RgnType;
/*************************************************************************
* ScrollWindow (USER.61)
*/
void ScrollWindow(HWND hwnd, short dx, short dy, LPRECT rect, LPRECT clipRect)
{
HDC hdc;
HRGN hrgnUpdate;
RECT rc, cliprc;
#ifdef DEBUG_SCROLL
printf("ScrollWindow: dx=%d, dy=%d, rect=%d,%d,%d,%d\n", dx, dy,
rect->left, rect->top, rect->right, rect->bottom);
#endif
hdc = GetDC(hwnd);
if (rect == NULL)
GetWindowRect(hwnd, &rc);
else
CopyRect(&rc, rect);
if (clipRect == NULL)
GetWindowRect(hwnd, &cliprc);
else
CopyRect(&cliprc, clipRect);
hrgnUpdate = CreateRectRgn(0, 0, 0, 0);
ScrollDC(hdc, dx, dy, &rc, &cliprc, hrgnUpdate, NULL);
InvalidateRgn(hwnd, hrgnUpdate, TRUE);
ReleaseDC(hwnd, hdc);
}
/*************************************************************************
* ScrollDC (USER.221)
*/
BOOL ScrollDC(HDC hdc, short dx, short dy, LPRECT rc, LPRECT cliprc,
HRGN hrgnUpdate, LPRECT rcUpdate)
{
HRGN hrgnClip, hrgn1, hrgn2;
POINT src, dest;
short width, height;
DC *dc = (DC *)GDI_GetObjPtr(hdc, DC_MAGIC);
#ifdef DEBUG_SCROLL
printf("ScrollDC: dx=%d, dy=%d, rc=%d,%d,%d,%d\n", dx, dy,
rc->left, rc->top, rc->right, rc->bottom);
#endif
if (rc == NULL)
return;
if (cliprc)
{
hrgnClip = CreateRectRgnIndirect(cliprc);
SelectClipRgn(hdc, hrgnClip);
}
if (dx > 0)
{
src.x = XDPTOLP(dc, rc->left);
dest.x = XDPTOLP(dc, rc->left + abs(dx));
}
else
{
src.x = XDPTOLP(dc, rc->left + abs(dx));
dest.x = XDPTOLP(dc, rc->left);
}
if (dy > 0)
{
src.y = YDPTOLP(dc, rc->top);
dest.y = YDPTOLP(dc, rc->top + abs(dy));
}
else
{
src.y = YDPTOLP(dc, rc->top + abs(dy));
dest.y = YDPTOLP(dc, rc->top);
}
width = rc->right - rc->left - abs(dx);
height = rc->bottom - rc->top - abs(dy);
if (!BitBlt(hdc, dest.x, dest.y, width, height, hdc, src.x, src.y,
SRCCOPY))
return;
if (hrgnUpdate)
{
if (dx > 0)
hrgn1 = CreateRectRgn(rc->left, rc->top, rc->left+dx, rc->bottom);
else if (dx < 0)
hrgn1 = CreateRectRgn(rc->right+dx, rc->top, rc->right,
rc->bottom);
else
hrgn1 = CreateRectRgn(0, 0, 0, 0);
if (dy > 0)
hrgn2 = CreateRectRgn(rc->left, rc->top, rc->right, rc->top+dy);
else if (dy < 0)
hrgn2 = CreateRectRgn(rc->left, rc->bottom+dy, rc->right,
rc->bottom);
else
hrgn2 = CreateRectRgn(0, 0, 0, 0);
RgnType = CombineRgn(hrgnUpdate, hrgn1, hrgn2, RGN_OR);
}
if (rcUpdate)
{
SelectClipRgn(hdc, hrgnUpdate);
GetClipBox(hdc, rcUpdate);
}
}
/*************************************************************************
* ScrollWindowEx (USER.319)
*/
int ScrollWindowEx(HWND hwnd, short dx, short dy, LPRECT rect, LPRECT clipRect,
HRGN hrgnUpdate, LPRECT rcUpdate, WORD flags)
{
HDC hdc;
RECT rc, cliprc;
#ifdef DEBUG_SCROLL
printf("ScrollWindowEx: dx=%d, dy=%d, rect=%d,%d,%d,%d\n", dx, dy,
rect->left, rect->top, rect->right, rect->bottom);
#endif
hdc = GetDC(hwnd);
if (rect == NULL)
GetWindowRect(hwnd, &rc);
else
CopyRect(&rc, rect);
if (clipRect == NULL)
GetWindowRect(hwnd, &cliprc);
else
CopyRect(&cliprc, clipRect);
ScrollDC(hdc, dx, dy, &rc, &cliprc, hrgnUpdate, rcUpdate);
if (flags | SW_INVALIDATE)
{
InvalidateRgn(hwnd, hrgnUpdate, FALSE);
if (flags | SW_ERASE)
SendMessage(hwnd, WM_ERASEBKGND, (WORD)hdc, (LONG)NULL);
}
ReleaseDC(hwnd, hdc);
return RgnType;
}