windows-nt/Source/XPSP1/NT/shell/shell32/drawpie.c
2020-09-26 16:20:57 +08:00

243 lines
6 KiB
C

#include "shellprv.h"
#pragma hdrstop
int IntSqrt(unsigned long dwNum)
{
// We will keep shifting dwNum left and look at the top two bits.
// initialize sqrt and remainder to 0.
DWORD dwSqrt = 0, dwRemain = 0, dwTry;
int i;
// We iterate 16 times, once for each pair of bits.
for (i=0; i<16; ++i)
{
// Mask off the top two bits of dwNum and rotate them into the
// bottom of the remainder
dwRemain = (dwRemain<<2) | (dwNum>>30);
// Now we shift the sqrt left; next we'll determine whether the
// new bit is a 1 or a 0.
dwSqrt <<= 1;
// This is where we double what we already have, and try a 1 in
// the lowest bit.
dwTry = dwSqrt*2 + 1;
if (dwRemain >= dwTry)
{
// The remainder was big enough, so subtract dwTry from
// the remainder and tack a 1 onto the sqrt.
dwRemain -= dwTry;
dwSqrt |= 0x01;
}
// Shift dwNum to the left by 2 so we can work on the next few
// bits.
dwNum <<= 2;
}
return(dwSqrt);
}
STDAPI_(VOID) DrawPie(HDC hDC, LPCRECT lprcItem, UINT uPctX10, BOOL TrueZr100,
UINT uOffset, const COLORREF *lpColors)
{
int cx, cy, rx, ry, x, y;
int uQPctX10;
RECT rcItem;
HRGN hEllRect, hEllipticRgn, hRectRgn;
HBRUSH hBrush, hOldBrush;
HPEN hPen, hOldPen;
DWORD dwOldLayout;
rcItem = *lprcItem;
rcItem.left = lprcItem->left;
rcItem.top = lprcItem->top;
rcItem.right = lprcItem->right - rcItem.left;
rcItem.bottom = lprcItem->bottom - rcItem.top - uOffset;
rx = rcItem.right / 2;
cx = rcItem.left + rx - 1;
ry = rcItem.bottom / 2;
cy = rcItem.top + ry - 1;
if (rx<=10 || ry<=10)
{
return;
}
dwOldLayout = SET_DC_LAYOUT(hDC, 0);
rcItem.right = rcItem.left+2*rx;
rcItem.bottom = rcItem.top+2*ry;
if (uPctX10 > 1000)
{
uPctX10 = 1000;
}
/* Translate to first quadrant of a Cartesian system
*/
uQPctX10 = (uPctX10 % 500) - 250;
if (uQPctX10 < 0)
{
uQPctX10 = -uQPctX10;
}
/* Calc x and y. I am trying to make the area be the right percentage.
** I don't know how to calculate the area of a pie slice exactly, so I
** approximate it by using the triangle area instead.
*/
if (uQPctX10 < 120)
{
x = IntSqrt(((DWORD)rx*(DWORD)rx*(DWORD)uQPctX10*(DWORD)uQPctX10)
/((DWORD)uQPctX10*(DWORD)uQPctX10+(250L-(DWORD)uQPctX10)*(250L-(DWORD)uQPctX10)));
y = IntSqrt(((DWORD)rx*(DWORD)rx-(DWORD)x*(DWORD)x)*(DWORD)ry*(DWORD)ry/((DWORD)rx*(DWORD)rx));
}
else
{
y = IntSqrt((DWORD)ry*(DWORD)ry*(250L-(DWORD)uQPctX10)*(250L-(DWORD)uQPctX10)
/((DWORD)uQPctX10*(DWORD)uQPctX10+(250L-(DWORD)uQPctX10)*(250L-(DWORD)uQPctX10)));
x = IntSqrt(((DWORD)ry*(DWORD)ry-(DWORD)y*(DWORD)y)*(DWORD)rx*(DWORD)rx/((DWORD)ry*(DWORD)ry));
}
/* Switch on the actual quadrant
*/
switch (uPctX10 / 250)
{
case 1:
y = -y;
break;
case 2:
break;
case 3:
x = -x;
break;
default: // case 0 and case 4
x = -x;
y = -y;
break;
}
/* Now adjust for the center.
*/
x += cx;
y += cy;
// Hack to get around bug in NTGDI
x = x < 0 ? 0 : x;
/* Draw the shadows using regions (to reduce flicker).
*/
hEllipticRgn = CreateEllipticRgnIndirect(&rcItem);
OffsetRgn(hEllipticRgn, 0, uOffset);
hEllRect = CreateRectRgn(rcItem.left, cy, rcItem.right, cy+uOffset);
hRectRgn = CreateRectRgn(0, 0, 0, 0);
CombineRgn(hRectRgn, hEllipticRgn, hEllRect, RGN_OR);
OffsetRgn(hEllipticRgn, 0, -(int)uOffset);
CombineRgn(hEllRect, hRectRgn, hEllipticRgn, RGN_DIFF);
/* Always draw the whole area in the free shadow/
*/
hBrush = CreateSolidBrush(lpColors[DP_FREESHADOW]);
if (hBrush)
{
FillRgn(hDC, hEllRect, hBrush);
DeleteObject(hBrush);
}
/* Draw the used shadow only if the disk is at least half used.
*/
if (uPctX10>500 && (hBrush=CreateSolidBrush(lpColors[DP_USEDSHADOW]))!=NULL)
{
DeleteObject(hRectRgn);
hRectRgn = CreateRectRgn(x, cy, rcItem.right, lprcItem->bottom);
CombineRgn(hEllipticRgn, hEllRect, hRectRgn, RGN_AND);
FillRgn(hDC, hEllipticRgn, hBrush);
DeleteObject(hBrush);
}
DeleteObject(hRectRgn);
DeleteObject(hEllipticRgn);
DeleteObject(hEllRect);
hPen = CreatePen(PS_SOLID, 1, GetSysColor(COLOR_WINDOWFRAME));
hOldPen = SelectObject(hDC, hPen);
if((uPctX10 < 100) && (cy == y))
{
hBrush = CreateSolidBrush(lpColors[DP_FREECOLOR]);
hOldBrush = SelectObject(hDC, hBrush);
if((TrueZr100 == FALSE) || (uPctX10 != 0))
{
Pie(hDC, rcItem.left, rcItem.top, rcItem.right, rcItem.bottom,
rcItem.left, cy, x, y);
}
else
{
Ellipse(hDC, rcItem.left, rcItem.top, rcItem.right,
rcItem.bottom);
}
}
else if((uPctX10 > (1000 - 100)) && (cy == y))
{
hBrush = CreateSolidBrush(lpColors[DP_USEDCOLOR]);
hOldBrush = SelectObject(hDC, hBrush);
if((TrueZr100 == FALSE) || (uPctX10 != 1000))
{
Pie(hDC, rcItem.left, rcItem.top, rcItem.right, rcItem.bottom,
rcItem.left, cy, x, y);
}
else
{
Ellipse(hDC, rcItem.left, rcItem.top, rcItem.right,
rcItem.bottom);
}
}
else
{
hBrush = CreateSolidBrush(lpColors[DP_USEDCOLOR]);
hOldBrush = SelectObject(hDC, hBrush);
Ellipse(hDC, rcItem.left, rcItem.top, rcItem.right, rcItem.bottom);
SelectObject(hDC, hOldBrush);
DeleteObject(hBrush);
hBrush = CreateSolidBrush(lpColors[DP_FREECOLOR]);
hOldBrush = SelectObject(hDC, hBrush);
Pie(hDC, rcItem.left, rcItem.top, rcItem.right, rcItem.bottom,
rcItem.left, cy, x, y);
}
SelectObject(hDC, hOldBrush);
DeleteObject(hBrush);
/* Do not draw the lines if the %age is truely 0 or 100 (completely
** empty disk or completly full disk)
*/
if((TrueZr100 == FALSE) || ((uPctX10 != 0) && (uPctX10 != 1000)))
{
Arc(hDC, rcItem.left, rcItem.top+uOffset, rcItem.right, rcItem.bottom+uOffset,
rcItem.left, cy+uOffset, rcItem.right, cy+uOffset-1);
MoveToEx(hDC, rcItem.left, cy, NULL);
LineTo(hDC, rcItem.left, cy+uOffset);
MoveToEx(hDC, rcItem.right-1, cy, NULL);
LineTo(hDC, rcItem.right-1, cy+uOffset);
if (uPctX10 > 500)
{
MoveToEx(hDC, x, y, NULL);
LineTo(hDC, x, y+uOffset);
}
}
SelectObject(hDC, hOldPen);
DeleteObject(hPen);
SET_DC_LAYOUT(hDC, dwOldLayout);
}