/*
 * tkWinDraw.c --
 *
 *	This file contains the Xlib emulation functions pertaining to actually
 *	drawing objects on a window.
 *
 * Copyright (c) 1995 Sun Microsystems, Inc.
 * Copyright (c) 1994 Software Research Associates, Inc.
 *
 * See the file "license.terms" for information on usage and redistribution of
 * this file, and for a DISCLAIMER OF ALL WARRANTIES.
 *
 * RCS: @(#) $Id: tkWinDraw.c,v 1.20 2007/12/13 15:28:55 dgp Exp $
 */

#include "tkWinInt.h"

/*
 * These macros convert between X's bizarre angle units to radians.
 */

#define PI 3.14159265358979
#define XAngleToRadians(a) ((double)(a) / 64 * PI / 180);

/*
 * Translation table between X gc functions and Win32 raster op modes.
 */

int tkpWinRopModes[] = {
    R2_BLACK,			/* GXclear */
    R2_MASKPEN,			/* GXand */
    R2_MASKPENNOT,		/* GXandReverse */
    R2_COPYPEN,			/* GXcopy */
    R2_MASKNOTPEN,		/* GXandInverted */
    R2_NOT,			/* GXnoop */
    R2_XORPEN,			/* GXxor */
    R2_MERGEPEN,		/* GXor */
    R2_NOTMERGEPEN,		/* GXnor */
    R2_NOTXORPEN,		/* GXequiv */
    R2_NOT,			/* GXinvert */
    R2_MERGEPENNOT,		/* GXorReverse */
    R2_NOTCOPYPEN,		/* GXcopyInverted */
    R2_MERGENOTPEN,		/* GXorInverted */
    R2_NOTMASKPEN,		/* GXnand */
    R2_WHITE			/* GXset */
};

/*
 * Translation table between X gc functions and Win32 BitBlt op modes. Some of
 * the operations defined in X don't have names, so we have to construct new
 * opcodes for those functions. This is arcane and probably not all that
 * useful, but at least it's accurate.
 */

#define NOTSRCAND	(DWORD)0x00220326 /* dest = (NOT source) AND dest */
#define NOTSRCINVERT	(DWORD)0x00990066 /* dest = (NOT source) XOR dest */
#define SRCORREVERSE	(DWORD)0x00DD0228 /* dest = source OR (NOT dest) */
#define SRCNAND		(DWORD)0x007700E6 /* dest = NOT (source AND dest) */

int tkpWinBltModes[] = {
    BLACKNESS,			/* GXclear */
    SRCAND,			/* GXand */
    SRCERASE,			/* GXandReverse */
    SRCCOPY,			/* GXcopy */
    NOTSRCAND,			/* GXandInverted */
    PATCOPY,			/* GXnoop */
    SRCINVERT,			/* GXxor */
    SRCPAINT,			/* GXor */
    NOTSRCERASE,		/* GXnor */
    NOTSRCINVERT,		/* GXequiv */
    DSTINVERT,			/* GXinvert */
    SRCORREVERSE,		/* GXorReverse */
    NOTSRCCOPY,			/* GXcopyInverted */
    MERGEPAINT,			/* GXorInverted */
    SRCNAND,			/* GXnand */
    WHITENESS			/* GXset */
};

/*
 * The following raster op uses the source bitmap as a mask for the pattern.
 * This is used to draw in a foreground color but leave the background color
 * transparent.
 */

#define MASKPAT		0x00E20746 /* dest = (src & pat) | (!src & dst) */

/*
 * The following two raster ops are used to copy the foreground and background
 * bits of a source pattern as defined by a stipple used as the pattern.
 */

#define COPYFG		0x00CA0749 /* dest = (pat & src) | (!pat & dst) */
#define COPYBG		0x00AC0744 /* dest = (!pat & src) | (pat & dst) */

/*
 * Macros used later in the file.
 */

#define MIN(a,b)	((a>b) ? b : a)
#define MAX(a,b)	((a<b) ? b : a)

/*
 * The followng typedef is used to pass Windows GDI drawing functions.
 */

typedef BOOL (CALLBACK *WinDrawFunc)(HDC dc, CONST POINT* points, int npoints);

typedef struct ThreadSpecificData {
    POINT *winPoints;		/* Array of points that is reused. */
    int nWinPoints;		/* Current size of point array. */
} ThreadSpecificData;
static Tcl_ThreadDataKey dataKey;

/*
 * Forward declarations for functions defined in this file:
 */

static POINT *		ConvertPoints(XPoint *points, int npoints, int mode,
			    RECT *bbox);
static void		DrawOrFillArc(Display *display, Drawable d, GC gc,
			    int x, int y, unsigned int width,
			    unsigned int height, int start, int extent,
			    int fill);
static void		RenderObject(HDC dc, GC gc, XPoint* points,
			    int npoints, int mode, HPEN pen, WinDrawFunc func);
static HPEN		SetUpGraphicsPort(GC gc);

/*
 *----------------------------------------------------------------------
 *
 * TkWinGetDrawableDC --
 *
 *	Retrieve the DC from a drawable.
 *
 * Results:
 *	Returns the window DC for windows. Returns a new memory DC for
 *	pixmaps.
 *
 * Side effects:
 *	Sets up the palette for the device context, and saves the old device
 *	context state in the passed in TkWinDCState structure.
 *
 *----------------------------------------------------------------------
 */

HDC
TkWinGetDrawableDC(
    Display *display,
    Drawable d,
    TkWinDCState *state)
{
    HDC dc;
    TkWinDrawable *twdPtr = (TkWinDrawable *)d;
    Colormap cmap;

    if (twdPtr->type == TWD_WINDOW) {
	TkWindow *winPtr = twdPtr->window.winPtr;

 	dc = GetDC(twdPtr->window.handle);
	if (winPtr == NULL) {
	    cmap = DefaultColormap(display, DefaultScreen(display));
	} else {
	    cmap = winPtr->atts.colormap;
	}
    } else if (twdPtr->type == TWD_WINDC) {
	dc = twdPtr->winDC.hdc;
	cmap = DefaultColormap(display, DefaultScreen(display));
    } else {
	dc = CreateCompatibleDC(NULL);
	SelectObject(dc, twdPtr->bitmap.handle);
	cmap = twdPtr->bitmap.colormap;
    }
    state->palette = TkWinSelectPalette(dc, cmap);
    state->bkmode  = GetBkMode(dc);
    return dc;
}

/*
 *----------------------------------------------------------------------
 *
 * TkWinReleaseDrawableDC --
 *
 *	Frees the resources associated with a drawable's DC.
 *
 * Results:
 *	None.
 *
 * Side effects:
 *	Restores the old bitmap handle to the memory DC for pixmaps.
 *
 *----------------------------------------------------------------------
 */

void
TkWinReleaseDrawableDC(
    Drawable d,
    HDC dc,
    TkWinDCState *state)
{
    TkWinDrawable *twdPtr = (TkWinDrawable *)d;

    SetBkMode(dc, state->bkmode);
    SelectPalette(dc, state->palette, TRUE);
    RealizePalette(dc);
    if (twdPtr->type == TWD_WINDOW) {
	ReleaseDC(TkWinGetHWND(d), dc);
    } else if (twdPtr->type == TWD_BITMAP) {
	DeleteDC(dc);
    }
}

/*
 *----------------------------------------------------------------------
 *
 * ConvertPoints --
 *
 *	Convert an array of X points to an array of Win32 points.
 *
 * Results:
 *	Returns the converted array of POINTs.
 *
 * Side effects:
 *	Allocates a block of memory in thread local storage that should not be
 *	freed.
 *
 *----------------------------------------------------------------------
 */

static POINT *
ConvertPoints(
    XPoint *points,
    int npoints,
    int mode,			/* CoordModeOrigin or CoordModePrevious. */
    RECT *bbox)			/* Bounding box of points. */
{
    ThreadSpecificData *tsdPtr = (ThreadSpecificData *)
	    Tcl_GetThreadData(&dataKey, sizeof(ThreadSpecificData));
    int i;

    /*
     * To avoid paying the cost of a malloc on every drawing routine, we reuse
     * the last array if it is large enough.
     */

    if (npoints > tsdPtr->nWinPoints) {
	if (tsdPtr->winPoints != NULL) {
	    ckfree((char *) tsdPtr->winPoints);
	}
	tsdPtr->winPoints = (POINT *) ckalloc(sizeof(POINT) * npoints);
	if (tsdPtr->winPoints == NULL) {
	    tsdPtr->nWinPoints = -1;
	    return NULL;
	}
	tsdPtr->nWinPoints = npoints;
    }

    bbox->left = bbox->right = points[0].x;
    bbox->top = bbox->bottom = points[0].y;

    if (mode == CoordModeOrigin) {
	for (i = 0; i < npoints; i++) {
	    tsdPtr->winPoints[i].x = points[i].x;
	    tsdPtr->winPoints[i].y = points[i].y;
	    bbox->left = MIN(bbox->left, tsdPtr->winPoints[i].x);
	    bbox->right = MAX(bbox->right, tsdPtr->winPoints[i].x);
	    bbox->top = MIN(bbox->top, tsdPtr->winPoints[i].y);
	    bbox->bottom = MAX(bbox->bottom, tsdPtr->winPoints[i].y);
	}
    } else {
	tsdPtr->winPoints[0].x = points[0].x;
	tsdPtr->winPoints[0].y = points[0].y;
	for (i = 1; i < npoints; i++) {
	    tsdPtr->winPoints[i].x = tsdPtr->winPoints[i-1].x + points[i].x;
	    tsdPtr->winPoints[i].y = tsdPtr->winPoints[i-1].y + points[i].y;
	    bbox->left = MIN(bbox->left, tsdPtr->winPoints[i].x);
	    bbox->right = MAX(bbox->right, tsdPtr->winPoints[i].x);
	    bbox->top = MIN(bbox->top, tsdPtr->winPoints[i].y);
	    bbox->bottom = MAX(bbox->bottom, tsdPtr->winPoints[i].y);
	}
    }
    return tsdPtr->winPoints;
}

/*
 *----------------------------------------------------------------------
 *
 * XCopyArea --
 *
 *	Copies data from one drawable to another using block transfer
 *	routines.
 *
 * Results:
 *	None.
 *
 * Side effects:
 *	Data is moved from a window or bitmap to a second window or bitmap.
 *
 *----------------------------------------------------------------------
 */

void
XCopyArea(
    Display *display,
    Drawable src,
    Drawable dest,
    GC gc,
    int src_x, int src_y,
    unsigned int width, unsigned int height,
    int dest_x, int dest_y)
{
    HDC srcDC, destDC;
    TkWinDCState srcState, destState;
    TkpClipMask *clipPtr = (TkpClipMask*)gc->clip_mask;

    srcDC = TkWinGetDrawableDC(display, src, &srcState);

    if (src != dest) {
	destDC = TkWinGetDrawableDC(display, dest, &destState);
    } else {
	destDC = srcDC;
    }

    if (clipPtr && clipPtr->type == TKP_CLIP_REGION) {
	SelectClipRgn(destDC, (HRGN) clipPtr->value.region);
	OffsetClipRgn(destDC, gc->clip_x_origin, gc->clip_y_origin);
    }

    BitBlt(destDC, dest_x, dest_y, (int) width, (int) height, srcDC,
	    src_x, src_y, (DWORD) tkpWinBltModes[gc->function]);

    SelectClipRgn(destDC, NULL);

    if (src != dest) {
	TkWinReleaseDrawableDC(dest, destDC, &destState);
    }
    TkWinReleaseDrawableDC(src, srcDC, &srcState);
}

/*
 *----------------------------------------------------------------------
 *
 * XCopyPlane --
 *
 *	Copies a bitmap from a source drawable to a destination drawable. The
 *	plane argument specifies which bit plane of the source contains the
 *	bitmap. Note that this implementation ignores the gc->function.
 *
 * Results:
 *	None.
 *
 * Side effects:
 *	Changes the destination drawable.
 *
 *----------------------------------------------------------------------
 */

void
XCopyPlane(
    Display *display,
    Drawable src,
    Drawable dest,
    GC gc,
    int src_x, int src_y,
    unsigned int width, unsigned int height,
    int dest_x, int dest_y,
    unsigned long plane)
{
    HDC srcDC, destDC;
    TkWinDCState srcState, destState;
    HBRUSH bgBrush, fgBrush, oldBrush;
    TkpClipMask *clipPtr = (TkpClipMask*)gc->clip_mask;

    display->request++;

    if (plane != 1) {
	Tcl_Panic("Unexpected plane specified for XCopyPlane");
    }

    srcDC = TkWinGetDrawableDC(display, src, &srcState);

    if (src != dest) {
	destDC = TkWinGetDrawableDC(display, dest, &destState);
    } else {
	destDC = srcDC;
    }

    if (clipPtr == NULL || clipPtr->type == TKP_CLIP_REGION) {
	/*
	 * Case 1: opaque bitmaps. Windows handles the conversion from one bit
	 * to multiple bits by setting 0 to the foreground color, and 1 to the
	 * background color (seems backwards, but there you are).
	 */

	if (clipPtr && clipPtr->type == TKP_CLIP_REGION) {
	    SelectClipRgn(destDC, (HRGN) clipPtr->value.region);
	    OffsetClipRgn(destDC, gc->clip_x_origin, gc->clip_y_origin);
	}

	SetBkMode(destDC, OPAQUE);
	SetBkColor(destDC, gc->foreground);
	SetTextColor(destDC, gc->background);
	BitBlt(destDC, dest_x, dest_y, (int) width, (int) height, srcDC,
		src_x, src_y, SRCCOPY);

	SelectClipRgn(destDC, NULL);
    } else if (clipPtr->type == TKP_CLIP_PIXMAP) {
	if (clipPtr->value.pixmap == src) {

	    /*
	     * Case 2: transparent bitmaps are handled by setting the
	     * destination to the foreground color whenever the source pixel
	     * is set.
	     */

	    fgBrush = CreateSolidBrush(gc->foreground);
	    oldBrush = SelectObject(destDC, fgBrush);
	    SetBkColor(destDC, RGB(255,255,255));
	    SetTextColor(destDC, RGB(0,0,0));
	    BitBlt(destDC, dest_x, dest_y, (int) width, (int) height, srcDC,
		    src_x, src_y, MASKPAT);
	    SelectObject(destDC, oldBrush);
	    DeleteObject(fgBrush);
	} else {

	    /*
	     * Case 3: two arbitrary bitmaps. Copy the source rectangle into a
	     * color pixmap. Use the result as a brush when copying the clip
	     * mask into the destination.
	     */

	    HDC memDC, maskDC;
	    HBITMAP bitmap;
	    TkWinDCState maskState;

	    fgBrush = CreateSolidBrush(gc->foreground);
	    bgBrush = CreateSolidBrush(gc->background);
	    maskDC = TkWinGetDrawableDC(display, clipPtr->value.pixmap,
		    &maskState);
	    memDC = CreateCompatibleDC(destDC);
	    bitmap = CreateBitmap((int) width, (int) height, 1, 1, NULL);
	    SelectObject(memDC, bitmap);

	    /*
	     * Set foreground bits. We create a new bitmap containing (source
	     * AND mask), then use it to set the foreground color into the
	     * destination.
	     */

	    BitBlt(memDC, 0, 0, (int) width, (int) height, srcDC, src_x, src_y,
		    SRCCOPY);
	    BitBlt(memDC, 0, 0, (int) width, (int) height, maskDC,
		    dest_x - gc->clip_x_origin, dest_y - gc->clip_y_origin,
		    SRCAND);
	    oldBrush = SelectObject(destDC, fgBrush);
	    BitBlt(destDC, dest_x, dest_y, (int) width, (int) height, memDC,
		    0, 0, MASKPAT);

	    /*
	     * Set background bits. Same as foreground, except we use ((NOT
	     * source) AND mask) and the background brush.
	     */

	    BitBlt(memDC, 0, 0, (int) width, (int) height, srcDC, src_x, src_y,
		    NOTSRCCOPY);
	    BitBlt(memDC, 0, 0, (int) width, (int) height, maskDC,
		    dest_x - gc->clip_x_origin, dest_y - gc->clip_y_origin,
		    SRCAND);
	    SelectObject(destDC, bgBrush);
	    BitBlt(destDC, dest_x, dest_y, (int) width, (int) height, memDC,
		    0, 0, MASKPAT);

	    TkWinReleaseDrawableDC(clipPtr->value.pixmap, maskDC, &maskState);
	    SelectObject(destDC, oldBrush);
	    DeleteDC(memDC);
	    DeleteObject(bitmap);
	    DeleteObject(fgBrush);
	    DeleteObject(bgBrush);
	}
    }
    if (src != dest) {
	TkWinReleaseDrawableDC(dest, destDC, &destState);
    }
    TkWinReleaseDrawableDC(src, srcDC, &srcState);
}

/*
 *----------------------------------------------------------------------
 *
 * TkPutImage --
 *
 *	Copies a subimage from an in-memory image to a rectangle of of the
 *	specified drawable.
 *
 * Results:
 *	None.
 *
 * Side effects:
 *	Draws the image on the specified drawable.
 *
 *----------------------------------------------------------------------
 */

void
TkPutImage(
    unsigned long *colors,	/* Array of pixel values used by this image.
				 * May be NULL. */
    int ncolors,		/* Number of colors used, or 0. */
    Display *display,
    Drawable d,			/* Destination drawable. */
    GC gc,
    XImage *image,		/* Source image. */
    int src_x, int src_y,	/* Offset of subimage. */
    int dest_x, int dest_y,	/* Position of subimage origin in drawable. */
    unsigned int width, unsigned int height)
				/* Dimensions of subimage. */
{
    HDC dc, dcMem;
    TkWinDCState state;
    BITMAPINFO *infoPtr;
    HBITMAP bitmap;
    char *data;

    display->request++;

    dc = TkWinGetDrawableDC(display, d, &state);
    SetROP2(dc, tkpWinRopModes[gc->function]);
    dcMem = CreateCompatibleDC(dc);

    if (image->bits_per_pixel == 1) {
	/*
	 * If the image isn't in the right format, we have to copy it into a
	 * new buffer in MSBFirst and word-aligned format.
	 */

	if ((image->bitmap_bit_order != MSBFirst)
		|| (image->bitmap_pad != sizeof(WORD))) {
	    data = TkAlignImageData(image, sizeof(WORD), MSBFirst);
	    bitmap = CreateBitmap(image->width, image->height, 1, 1, data);
	    ckfree(data);
	} else {
	    bitmap = CreateBitmap(image->width, image->height, 1, 1,
		    image->data);
	}
	SetTextColor(dc, gc->foreground);
	SetBkColor(dc, gc->background);
    } else {
	int i, usePalette;

	/*
	 * Do not use a palette for TrueColor images.
	 */

	usePalette = (image->bits_per_pixel < 16);

	if (usePalette) {
	    infoPtr = (BITMAPINFO *) ckalloc(sizeof(BITMAPINFOHEADER)
		    + sizeof(RGBQUAD)*ncolors);
	} else {
	    infoPtr = (BITMAPINFO *) ckalloc(sizeof(BITMAPINFOHEADER));
	}

	infoPtr->bmiHeader.biSize = sizeof(BITMAPINFOHEADER);
	infoPtr->bmiHeader.biWidth = image->width;
	infoPtr->bmiHeader.biHeight = -image->height; /* Top-down order */
	infoPtr->bmiHeader.biPlanes = 1;
	infoPtr->bmiHeader.biBitCount = image->bits_per_pixel;
	infoPtr->bmiHeader.biCompression = BI_RGB;
	infoPtr->bmiHeader.biSizeImage = 0;
	infoPtr->bmiHeader.biXPelsPerMeter = 0;
	infoPtr->bmiHeader.biYPelsPerMeter = 0;
	infoPtr->bmiHeader.biClrImportant = 0;

	if (usePalette) {
	    infoPtr->bmiHeader.biClrUsed = ncolors;
	    for (i = 0; i < ncolors; i++) {
		infoPtr->bmiColors[i].rgbBlue = GetBValue(colors[i]);
		infoPtr->bmiColors[i].rgbGreen = GetGValue(colors[i]);
		infoPtr->bmiColors[i].rgbRed = GetRValue(colors[i]);
		infoPtr->bmiColors[i].rgbReserved = 0;
	    }
	} else {
	    infoPtr->bmiHeader.biClrUsed = 0;
	}
	bitmap = CreateDIBitmap(dc, &infoPtr->bmiHeader, CBM_INIT,
		image->data, infoPtr, DIB_RGB_COLORS);
	ckfree((char *) infoPtr);
    }
    if (!bitmap) {
	Tcl_Panic("Fail to allocate bitmap\n");
	DeleteDC(dcMem);
    	TkWinReleaseDrawableDC(d, dc, &state);
	return;
    }
    bitmap = SelectObject(dcMem, bitmap);
    BitBlt(dc, dest_x, dest_y, (int) width, (int) height, dcMem, src_x, src_y,
	    SRCCOPY);
    DeleteObject(SelectObject(dcMem, bitmap));
    DeleteDC(dcMem);
    TkWinReleaseDrawableDC(d, dc, &state);
}

/*
 *----------------------------------------------------------------------
 *
 * XFillRectangles --
 *
 *	Fill multiple rectangular areas in the given drawable.
 *
 * Results:
 *	None.
 *
 * Side effects:
 *	Draws onto the specified drawable.
 *
 *----------------------------------------------------------------------
 */

void
XFillRectangles(
    Display *display,
    Drawable d,
    GC gc,
    XRectangle *rectangles,
    int nrectangles)
{
    HDC dc;
    int i;
    RECT rect;
    TkWinDCState state;
    HBRUSH brush, oldBrush;

    if (d == None) {
	return;
    }

    dc = TkWinGetDrawableDC(display, d, &state);
    SetROP2(dc, tkpWinRopModes[gc->function]);
    brush = CreateSolidBrush(gc->foreground);

    if ((gc->fill_style == FillStippled
	    || gc->fill_style == FillOpaqueStippled)
	    && gc->stipple != None) {
	TkWinDrawable *twdPtr = (TkWinDrawable *)gc->stipple;
	HBRUSH stipple;
	HBITMAP oldBitmap, bitmap;
	HDC dcMem;
	HBRUSH bgBrush = CreateSolidBrush(gc->background);

	if (twdPtr->type != TWD_BITMAP) {
	    Tcl_Panic("unexpected drawable type in stipple");
	}

	/*
	 * Select stipple pattern into destination dc.
	 */

	stipple = CreatePatternBrush(twdPtr->bitmap.handle);
	SetBrushOrgEx(dc, gc->ts_x_origin, gc->ts_y_origin, NULL);
	oldBrush = SelectObject(dc, stipple);
	dcMem = CreateCompatibleDC(dc);

	/*
	 * For each rectangle, create a drawing surface which is the size of
	 * the rectangle and fill it with the background color. Then merge the
	 * result with the stipple pattern.
	 */

	for (i = 0; i < nrectangles; i++) {
	    bitmap = CreateCompatibleBitmap(dc, rectangles[i].width,
		    rectangles[i].height);
	    oldBitmap = SelectObject(dcMem, bitmap);
	    rect.left = 0;
	    rect.top = 0;
	    rect.right = rectangles[i].width;
	    rect.bottom = rectangles[i].height;
	    FillRect(dcMem, &rect, brush);
	    BitBlt(dc, rectangles[i].x, rectangles[i].y, rectangles[i].width,
		    rectangles[i].height, dcMem, 0, 0, COPYFG);
	    if (gc->fill_style == FillOpaqueStippled) {
		FillRect(dcMem, &rect, bgBrush);
		BitBlt(dc, rectangles[i].x, rectangles[i].y,
			rectangles[i].width, rectangles[i].height, dcMem,
			0, 0, COPYBG);
	    }
	    SelectObject(dcMem, oldBitmap);
	    DeleteObject(bitmap);
	}

	DeleteDC(dcMem);
	SelectObject(dc, oldBrush);
	DeleteObject(stipple);
	DeleteObject(bgBrush);
    } else {
	if (gc->function == GXcopy) {
	    for (i = 0; i < nrectangles; i++) {
		rect.left = rectangles[i].x;
		rect.right = rect.left + rectangles[i].width;
		rect.top = rectangles[i].y;
		rect.bottom = rect.top + rectangles[i].height;
		FillRect(dc, &rect, brush);
	    }
	} else {
	    HPEN newPen = CreatePen(PS_NULL, 0, gc->foreground);
	    HPEN oldPen = SelectObject(dc, newPen);
	    oldBrush = SelectObject(dc, brush);

	    for (i = 0; i < nrectangles; i++) {
		Rectangle(dc, rectangles[i].x, rectangles[i].y,
		    rectangles[i].x + rectangles[i].width + 1,
		    rectangles[i].y + rectangles[i].height + 1);
	    }

	    SelectObject(dc, oldBrush);
	    SelectObject(dc, oldPen);
	    DeleteObject(newPen);
	}
    }
    DeleteObject(brush);
    TkWinReleaseDrawableDC(d, dc, &state);
}

/*
 *----------------------------------------------------------------------
 *
 * RenderObject --
 *
 *	This function draws a shape using a list of points, a stipple pattern,
 *	and the specified drawing function.
 *
 * Results:
 *	None.
 *
 * Side effects:
 *	None.
 *
 *----------------------------------------------------------------------
 */

static void
RenderObject(
    HDC dc,
    GC gc,
    XPoint *points,
    int npoints,
    int mode,
    HPEN pen,
    WinDrawFunc func)
{
    RECT rect;
    HPEN oldPen;
    HBRUSH oldBrush;
    POINT *winPoints = ConvertPoints(points, npoints, mode, &rect);

    if ((gc->fill_style == FillStippled
	    || gc->fill_style == FillOpaqueStippled)
	    && gc->stipple != None) {

	TkWinDrawable *twdPtr = (TkWinDrawable *)gc->stipple;
	HDC dcMem;
	LONG width, height;
	HBITMAP oldBitmap;
	int i;
	HBRUSH oldMemBrush;

	if (twdPtr->type != TWD_BITMAP) {
	    Tcl_Panic("unexpected drawable type in stipple");
	}

	/*
	 * Grow the bounding box enough to account for line width.
	 */

	rect.left -= gc->line_width;
	rect.top -= gc->line_width;
	rect.right += gc->line_width;
	rect.bottom += gc->line_width;

	width = rect.right - rect.left;
	height = rect.bottom - rect.top;

	/*
	 * Select stipple pattern into destination dc.
	 */

	SetBrushOrgEx(dc, gc->ts_x_origin, gc->ts_y_origin, NULL);
	oldBrush = SelectObject(dc, CreatePatternBrush(twdPtr->bitmap.handle));

	/*
	 * Create temporary drawing surface containing a copy of the
	 * destination equal in size to the bounding box of the object.
	 */

	dcMem = CreateCompatibleDC(dc);
	oldBitmap = SelectObject(dcMem, CreateCompatibleBitmap(dc, width,
		height));
	oldPen = SelectObject(dcMem, pen);
	BitBlt(dcMem, 0, 0, width, height, dc, rect.left, rect.top, SRCCOPY);

	/*
	 * Translate the object for rendering in the temporary drawing
	 * surface.
	 */

	for (i = 0; i < npoints; i++) {
	    winPoints[i].x -= rect.left;
	    winPoints[i].y -= rect.top;
	}

	/*
	 * Draw the object in the foreground color and copy it to the
	 * destination wherever the pattern is set.
	 */

	SetPolyFillMode(dcMem, (gc->fill_rule == EvenOddRule) ? ALTERNATE
		: WINDING);
	oldMemBrush = SelectObject(dcMem, CreateSolidBrush(gc->foreground));
	(*func)(dcMem, winPoints, npoints);
	BitBlt(dc, rect.left, rect.top, width, height, dcMem, 0, 0, COPYFG);

	/*
	 * If we are rendering an opaque stipple, then draw the polygon in the
	 * background color and copy it to the destination wherever the
	 * pattern is clear.
	 */

	if (gc->fill_style == FillOpaqueStippled) {
	    DeleteObject(SelectObject(dcMem,
		    CreateSolidBrush(gc->background)));
	    (*func)(dcMem, winPoints, npoints);
	    BitBlt(dc, rect.left, rect.top, width, height, dcMem, 0, 0,
		    COPYBG);
	}

	SelectObject(dcMem, oldPen);
	DeleteObject(SelectObject(dcMem, oldMemBrush));
	DeleteObject(SelectObject(dcMem, oldBitmap));
	DeleteDC(dcMem);
    } else {
	oldPen = SelectObject(dc, pen);
	oldBrush = SelectObject(dc, CreateSolidBrush(gc->foreground));
	SetROP2(dc, tkpWinRopModes[gc->function]);

	SetPolyFillMode(dc, (gc->fill_rule == EvenOddRule) ? ALTERNATE
		: WINDING);

	(*func)(dc, winPoints, npoints);

	SelectObject(dc, oldPen);
    }
    DeleteObject(SelectObject(dc, oldBrush));
}

/*
 *----------------------------------------------------------------------
 *
 * XDrawLines --
 *
 *	Draw connected lines.
 *
 * Results:
 *	None.
 *
 * Side effects:
 *	Renders a series of connected lines.
 *
 *----------------------------------------------------------------------
 */

void
XDrawLines(
    Display *display,
    Drawable d,
    GC gc,
    XPoint *points,
    int npoints,
    int mode)
{
    HPEN pen;
    TkWinDCState state;
    HDC dc;

    if (d == None) {
	return;
    }

    dc = TkWinGetDrawableDC(display, d, &state);

    pen = SetUpGraphicsPort(gc);
    SetBkMode(dc, TRANSPARENT);
    RenderObject(dc, gc, points, npoints, mode, pen, Polyline);
    DeleteObject(pen);

    TkWinReleaseDrawableDC(d, dc, &state);
}

/*
 *----------------------------------------------------------------------
 *
 * XFillPolygon --
 *
 *	Draws a filled polygon.
 *
 * Results:
 *	None.
 *
 * Side effects:
 *	Draws a filled polygon on the specified drawable.
 *
 *----------------------------------------------------------------------
 */

void
XFillPolygon(
    Display *display,
    Drawable d,
    GC gc,
    XPoint *points,
    int npoints,
    int shape,
    int mode)
{
    HPEN pen;
    TkWinDCState state;
    HDC dc;

    if (d == None) {
	return;
    }

    dc = TkWinGetDrawableDC(display, d, &state);

    pen = GetStockObject(NULL_PEN);
    RenderObject(dc, gc, points, npoints, mode, pen, Polygon);

    TkWinReleaseDrawableDC(d, dc, &state);
}

/*
 *----------------------------------------------------------------------
 *
 * XDrawRectangle --
 *
 *	Draws a rectangle.
 *
 * Results:
 *	None.
 *
 * Side effects:
 *	Draws a rectangle on the specified drawable.
 *
 *----------------------------------------------------------------------
 */

void
XDrawRectangle(
    Display *display,
    Drawable d,
    GC gc,
    int x, int y,
    unsigned int width, unsigned int height)
{
    HPEN pen, oldPen;
    TkWinDCState state;
    HBRUSH oldBrush;
    HDC dc;

    if (d == None) {
	return;
    }

    dc = TkWinGetDrawableDC(display, d, &state);

    pen = SetUpGraphicsPort(gc);
    SetBkMode(dc, TRANSPARENT);
    oldPen = SelectObject(dc, pen);
    oldBrush = SelectObject(dc, GetStockObject(NULL_BRUSH));
    SetROP2(dc, tkpWinRopModes[gc->function]);

    Rectangle(dc, x, y, (int) x+width+1, (int) y+height+1);

    DeleteObject(SelectObject(dc, oldPen));
    SelectObject(dc, oldBrush);
    TkWinReleaseDrawableDC(d, dc, &state);
}

/*
 *----------------------------------------------------------------------
 *
 * XDrawArc --
 *
 *	Draw an arc.
 *
 * Results:
 *	None.
 *
 * Side effects:
 *	Draws an arc on the specified drawable.
 *
 *----------------------------------------------------------------------
 */

void
XDrawArc(
    Display *display,
    Drawable d,
    GC gc,
    int x, int y,
    unsigned int width, unsigned int height,
    int start, int extent)
{
    display->request++;

    DrawOrFillArc(display, d, gc, x, y, width, height, start, extent, 0);
}

/*
 *----------------------------------------------------------------------
 *
 * XFillArc --
 *
 *	Draw a filled arc.
 *
 * Results:
 *	None.
 *
 * Side effects:
 *	Draws a filled arc on the specified drawable.
 *
 *----------------------------------------------------------------------
 */

void
XFillArc(
    Display *display,
    Drawable d,
    GC gc,
    int x, int y,
    unsigned int width, unsigned int height,
    int start, int extent)
{
    display->request++;

    DrawOrFillArc(display, d, gc, x, y, width, height, start, extent, 1);
}

/*
 *----------------------------------------------------------------------
 *
 * DrawOrFillArc --
 *
 *	This function handles the rendering of drawn or filled arcs and
 *	chords.
 *
 * Results:
 *	None.
 *
 * Side effects:
 *	Renders the requested arc.
 *
 *----------------------------------------------------------------------
 */

static void
DrawOrFillArc(
    Display *display,
    Drawable d,
    GC gc,
    int x, int y,		/* left top */
    unsigned int width, unsigned int height,
    int start,			/* start: three-o'clock (deg*64) */
    int extent,			/* extent: relative (deg*64) */
    int fill)			/* ==0 draw, !=0 fill */
{
    HDC dc;
    HBRUSH brush, oldBrush;
    HPEN pen, oldPen;
    TkWinDCState state;
    int clockwise = (extent < 0); /* non-zero if clockwise */
    int xstart, ystart, xend, yend;
    double radian_start, radian_end, xr, yr;

    if (d == None) {
	return;
    }

    dc = TkWinGetDrawableDC(display, d, &state);

    SetROP2(dc, tkpWinRopModes[gc->function]);

    /*
     * Compute the absolute starting and ending angles in normalized radians.
     * Swap the start and end if drawing clockwise.
     */

    start = start % (64*360);
    if (start < 0) {
	start += (64*360);
    }
    extent = (start+extent) % (64*360);
    if (extent < 0) {
	extent += (64*360);
    }
    if (clockwise) {
	int tmp = start;
	start = extent;
	extent = tmp;
    }
    radian_start = XAngleToRadians(start);
    radian_end = XAngleToRadians(extent);

    /*
     * Now compute points on the radial lines that define the starting and
     * ending angles. Be sure to take into account that the y-coordinate
     * system is inverted.
     */

    xr = x + width / 2.0;
    yr = y + height / 2.0;
    xstart = (int)((xr + cos(radian_start)*width/2.0) + 0.5);
    ystart = (int)((yr + sin(-radian_start)*height/2.0) + 0.5);
    xend = (int)((xr + cos(radian_end)*width/2.0) + 0.5);
    yend = (int)((yr + sin(-radian_end)*height/2.0) + 0.5);

    /*
     * Now draw a filled or open figure. Note that we have to increase the
     * size of the bounding box by one to account for the difference in pixel
     * definitions between X and Windows.
     */

    pen = SetUpGraphicsPort(gc);
    oldPen = SelectObject(dc, pen);
    if (!fill) {
	/*
	 * Note that this call will leave a gap of one pixel at the end of the
	 * arc for thin arcs. We can't use ArcTo because it's only supported
	 * under Windows NT.
	 */

	SetBkMode(dc, TRANSPARENT);
	Arc(dc, x, y, (int) (x+width+1), (int) (y+height+1), xstart, ystart,
		xend, yend);
    } else {
	brush = CreateSolidBrush(gc->foreground);
	oldBrush = SelectObject(dc, brush);
	if (gc->arc_mode == ArcChord) {
	    Chord(dc, x, y, (int) (x+width+1), (int) (y+height+1),
		    xstart, ystart, xend, yend);
	} else if (gc->arc_mode == ArcPieSlice) {
	    Pie(dc, x, y, (int) (x+width+1), (int) (y+height+1),
		    xstart, ystart, xend, yend);
	}
	DeleteObject(SelectObject(dc, oldBrush));
    }
    DeleteObject(SelectObject(dc, oldPen));
    TkWinReleaseDrawableDC(d, dc, &state);
}

/*
 *----------------------------------------------------------------------
 *
 * SetUpGraphicsPort --
 *
 *	Set up the graphics port from the given GC.
 *
 * Results:
 *	None.
 *
 * Side effects:
 *	The current port is adjusted.
 *
 *----------------------------------------------------------------------
 */

static HPEN
SetUpGraphicsPort(
    GC gc)
{
    DWORD style;

    if (gc->line_style == LineOnOffDash) {
	unsigned char *p = (unsigned char *) &(gc->dashes);
				/* pointer to the dash-list */

	/*
	 * Below is a simple translation of serveral dash patterns to valid
	 * windows pen types. Far from complete, but I don't know how to do it
	 * better. Any ideas: <mailto:j.nijtmans@chello.nl>
	 */

	if (p[1] && p[2]) {
	    if (!p[3] || p[4]) {
		style = PS_DASHDOTDOT;		/*	-..	*/
	    } else {
		style = PS_DASHDOT;		/*	-.	*/
	    }
	} else {
	    if (p[0] > (4 * gc->line_width)) {
		style = PS_DASH;		/*	-	*/
	    } else {
		style = PS_DOT;			/*	.	*/
	    }
	}
    } else {
	style = PS_SOLID;
    }
    if (gc->line_width < 2) {
	return CreatePen((int) style, gc->line_width, gc->foreground);
    } else {
	LOGBRUSH lb;

	lb.lbStyle = BS_SOLID;
	lb.lbColor = gc->foreground;
	lb.lbHatch = 0;

	style |= PS_GEOMETRIC;
	switch (gc->cap_style) {
	case CapNotLast:
	case CapButt:
	    style |= PS_ENDCAP_FLAT;
	    break;
	case CapRound:
	    style |= PS_ENDCAP_ROUND;
	    break;
	default:
	    style |= PS_ENDCAP_SQUARE;
	    break;
	}
	switch (gc->join_style) {
	case JoinMiter:
	    style |= PS_JOIN_MITER;
	    break;
	case JoinRound:
	    style |= PS_JOIN_ROUND;
	    break;
	default:
	    style |= PS_JOIN_BEVEL;
	    break;
	}
	return ExtCreatePen(style, (DWORD) gc->line_width, &lb, 0, NULL);
    }
}

/*
 *----------------------------------------------------------------------
 *
 * TkScrollWindow --
 *
 *	Scroll a rectangle of the specified window and accumulate a damage
 *	region.
 *
 * Results:
 *	Returns 0 if the scroll genereated no additional damage. Otherwise,
 *	sets the region that needs to be repainted after scrolling and returns
 *	1.
 *
 * Side effects:
 *	Scrolls the bits in the window.
 *
 *----------------------------------------------------------------------
 */

int
TkScrollWindow(
    Tk_Window tkwin,		/* The window to be scrolled. */
    GC gc,			/* GC for window to be scrolled. */
    int x, int y, int width, int height,
				/* Position rectangle to be scrolled. */
    int dx, int dy,		/* Distance rectangle should be moved. */
    TkRegion damageRgn)		/* Region to accumulate damage in. */
{
    HWND hwnd = TkWinGetHWND(Tk_WindowId(tkwin));
    RECT scrollRect;

    scrollRect.left = x;
    scrollRect.top = y;
    scrollRect.right = x + width;
    scrollRect.bottom = y + height;
    return (ScrollWindowEx(hwnd, dx, dy, &scrollRect, NULL, (HRGN) damageRgn,
	    NULL, 0) == NULLREGION) ? 0 : 1;
}

/*
 *----------------------------------------------------------------------
 *
 * TkWinFillRect --
 *
 *	This routine fills a rectangle with the foreground color from the
 *	specified GC ignoring all other GC values. This is the fastest way to
 *	fill a drawable with a solid color.
 *
 * Results:
 *	None.
 *
 * Side effects:
 *	Modifies the contents of the DC drawing surface.
 *
 *----------------------------------------------------------------------
 */

void
TkWinFillRect(
    HDC dc,
    int x, int y, int width, int height,
    int pixel)
{
    RECT rect;
    COLORREF oldColor;

    rect.left = x;
    rect.top = y;
    rect.right = x + width;
    rect.bottom = y + height;
    oldColor = SetBkColor(dc, (COLORREF)pixel);
    SetBkMode(dc, OPAQUE);
    ExtTextOut(dc, 0, 0, ETO_OPAQUE, &rect, NULL, 0, NULL);
    SetBkColor(dc, oldColor);
}

/*
 *----------------------------------------------------------------------
 *
 * TkpDrawHighlightBorder --
 *
 *	This function draws a rectangular ring around the outside of a widget
 *	to indicate that it has received the input focus.
 *
 *      On Windows, we just draw the simple inset ring. On other sytems, e.g.
 *      the Mac, the focus ring is a little more complicated, so we need this
 *      abstraction.
 *
 * Results:
 *	None.
 *
 * Side effects:
 *	A rectangle "width" pixels wide is drawn in "drawable", corresponding
 *	to the outer area of "tkwin".
 *
 *----------------------------------------------------------------------
 */

void
TkpDrawHighlightBorder(
    Tk_Window tkwin,
    GC fgGC,
    GC bgGC,
    int highlightWidth,
    Drawable drawable)
{
    TkDrawInsetFocusHighlight(tkwin, fgGC, highlightWidth, drawable, 0);
}

/*
 *----------------------------------------------------------------------
 *
 * TkpDrawFrame --
 *
 *	This function draws the rectangular frame area.
 *
 * Results:
 *	None.
 *
 * Side effects:
 *	Draws inside the tkwin area.
 *
 *----------------------------------------------------------------------
 */

void
TkpDrawFrame(
    Tk_Window tkwin,
    Tk_3DBorder border,
    int highlightWidth,
    int borderWidth,
    int relief)
{
    Tk_Fill3DRectangle(tkwin, Tk_WindowId(tkwin), border, highlightWidth,
	    highlightWidth, Tk_Width(tkwin) - 2 * highlightWidth,
	    Tk_Height(tkwin) - 2 * highlightWidth, borderWidth, relief);
}

/*
 * Local Variables:
 * mode: c
 * c-basic-offset: 4
 * fill-column: 78
 * End:
 */
