lineto.c

这是一个开放源代码的与WINNT/WIN2K/WIN2003兼容的操作系统

/*
 *  ReactOS W32 Subsystem
 *  Copyright (C) 1998, 1999, 2000, 2001, 2002, 2003 ReactOS Team
 *
 *  This program is free software; you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License as published by
 *  the Free Software Foundation; either version 2 of the License, or
 *  (at your option) any later version.
 *
 *  This program is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *  GNU General Public License for more details.
 *
 *  You should have received a copy of the GNU General Public License
 *  along with this program; if not, write to the Free Software
 *  Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 *
 * $Id: lineto.c 21292 2006-03-11 23:50:04Z jimtabor $
 */

#include <w32k.h>

#define NDEBUG
#include <debug.h>

static void FASTCALL
TranslateRects(RECT_ENUM *RectEnum, POINTL* Translate)
{
  RECTL* CurrentRect;

  if (0 != Translate->x || 0 != Translate->y)
    {
      for (CurrentRect = RectEnum->arcl; CurrentRect < RectEnum->arcl + RectEnum->c; CurrentRect++)
	{
	  CurrentRect->left += Translate->x;
	  CurrentRect->right += Translate->x;
	  CurrentRect->top += Translate->y;
	  CurrentRect->bottom += Translate->y;
	}
    }
}

/*
 * Draw a line from top-left to bottom-right
 */
void FASTCALL
NWtoSE(SURFOBJ* OutputObj, CLIPOBJ* Clip,
       BRUSHOBJ* Brush, LONG x, LONG y, LONG deltax, LONG deltay,
       POINTL* Translate)
{
  int i;
  int error;
  BOOLEAN EnumMore;
  RECTL* ClipRect;
  RECT_ENUM RectEnum;
  ULONG Pixel = Brush->iSolidColor;
  LONG delta;

  CLIPOBJ_cEnumStart(Clip, FALSE, CT_RECTANGLES, CD_RIGHTDOWN, 0);
  EnumMore = CLIPOBJ_bEnum(Clip, (ULONG) sizeof(RectEnum), (PVOID) &RectEnum);
  TranslateRects(&RectEnum, Translate);
  ClipRect = RectEnum.arcl;
  delta = max(deltax, deltay);
  i = 0;
  error = delta >> 1;
  while (i < delta && (ClipRect < RectEnum.arcl + RectEnum.c || EnumMore))
    {
      while ((ClipRect < RectEnum.arcl + RectEnum.c /* there's still a current clip rect */
              && (ClipRect->bottom <= y             /* but it's above us */
                  || (ClipRect->top <= y && ClipRect->right <= x))) /* or to the left of us */
             || EnumMore)                           /* no current clip rect, but rects left */
	{
	  /* Skip to the next clip rect */
	  if (RectEnum.arcl + RectEnum.c <= ClipRect)
	    {
	      EnumMore = CLIPOBJ_bEnum(Clip, (ULONG) sizeof(RectEnum), (PVOID) &RectEnum);
	      TranslateRects(&RectEnum, Translate);
	      ClipRect = RectEnum.arcl;
	    }
	  else
	    {
	      ClipRect++;
	    }
	}
      if (ClipRect < RectEnum.arcl + RectEnum.c) /* If there's no current clip rect we're done */
	{
	  if (ClipRect->left <= x && ClipRect->top <= y)
	    {
              DibFunctionsForBitmapFormat[OutputObj->iBitmapFormat].DIB_PutPixel(
                OutputObj, x, y, Pixel);
	    }
	  if (deltax < deltay)
	    {
	      y++;
	      error = error + deltax;
	      if (deltay <= error)
		{
		  x++;
		  error = error - deltay;
		}
	    }
	  else
	    {
	      x++;
	      error = error + deltay;
	      if (deltax <= error)
		{
	  	  y++;
		  error = error - deltax;
		}
	    }
	  i++;
	}
    }
}

void FASTCALL
SWtoNE(SURFOBJ* OutputObj, CLIPOBJ* Clip,
       BRUSHOBJ* Brush, LONG x, LONG y, LONG deltax, LONG deltay,
       POINTL* Translate)
{
  int i;
  int error;
  BOOLEAN EnumMore;
  RECTL* ClipRect;
  RECT_ENUM RectEnum;
  ULONG Pixel = Brush->iSolidColor;
  LONG delta;

  CLIPOBJ_cEnumStart(Clip, FALSE, CT_RECTANGLES, CD_RIGHTUP, 0);
  EnumMore = CLIPOBJ_bEnum(Clip, (ULONG) sizeof(RectEnum), (PVOID) &RectEnum);
  TranslateRects(&RectEnum, Translate);
  ClipRect = RectEnum.arcl;
  delta = max(deltax, deltay);
  i = 0;
  error = delta >> 1;
  while (i < delta && (ClipRect < RectEnum.arcl + RectEnum.c || EnumMore))
    {
      while ((ClipRect < RectEnum.arcl + RectEnum.c
              && (y < ClipRect->top
                  || (y < ClipRect->bottom && ClipRect->right <= x)))
             || EnumMore)
	{
	  if (RectEnum.arcl + RectEnum.c <= ClipRect)
	    {
	      EnumMore = CLIPOBJ_bEnum(Clip, (ULONG) sizeof(RectEnum), (PVOID) &RectEnum);
	      TranslateRects(&RectEnum, Translate);
	      ClipRect = RectEnum.arcl;
	    }
	  else
	    {
	      ClipRect++;
	    }
	}
      if (ClipRect < RectEnum.arcl + RectEnum.c)
	{
	  if (ClipRect->left <= x && y < ClipRect->bottom)
	    {
              DibFunctionsForBitmapFormat[OutputObj->iBitmapFormat].DIB_PutPixel(
	        OutputObj, x, y, Pixel);
	    }
	  if (deltax < deltay)
	    {
	      y--;
	      error = error + deltax;
	      if (deltay <= error)
		{
		  x++;
		  error = error - deltay;
		}
	    }
	  else
	    {
	      x++;
	      error = error + deltay;
	      if (deltax <= error)
		{
	  	  y--;
		  error = error - deltax;
		}
	    }
	  i++;
	}
    }
}

void FASTCALL
NEtoSW(SURFOBJ* OutputObj, CLIPOBJ* Clip,
       BRUSHOBJ* Brush, LONG x, LONG y, LONG deltax, LONG deltay,
       POINTL* Translate)
{
  int i;
  int error;
  BOOLEAN EnumMore;
  RECTL* ClipRect;
  RECT_ENUM RectEnum;
  ULONG Pixel = Brush->iSolidColor;
  LONG delta;

  CLIPOBJ_cEnumStart(Clip, FALSE, CT_RECTANGLES, CD_LEFTDOWN, 0);
  EnumMore = CLIPOBJ_bEnum(Clip, (ULONG) sizeof(RectEnum), (PVOID) &RectEnum);
  TranslateRects(&RectEnum, Translate);
  ClipRect = RectEnum.arcl;
  delta = max(deltax, deltay);
  i = 0;
  error = delta >> 1;
  while (i < delta && (ClipRect < RectEnum.arcl + RectEnum.c || EnumMore))
    {
      while ((ClipRect < RectEnum.arcl + RectEnum.c
              && (ClipRect->bottom <= y
                  || (ClipRect->top <= y && x < ClipRect->left)))
             || EnumMore)
	{
	  if (RectEnum.arcl + RectEnum.c <= ClipRect)
	    {
	      EnumMore = CLIPOBJ_bEnum(Clip, (ULONG) sizeof(RectEnum), (PVOID) &RectEnum);
	      TranslateRects(&RectEnum, Translate);
	      ClipRect = RectEnum.arcl;
	    }
	  else
	    {
	      ClipRect++;
	    }
	}
      if (ClipRect < RectEnum.arcl + RectEnum.c)
	{
	  if (x < ClipRect->right && ClipRect->top <= y)
	    {
              DibFunctionsForBitmapFormat[OutputObj->iBitmapFormat].DIB_PutPixel(
	        OutputObj, x, y, Pixel);
	    }
	  if (deltax < deltay)
	    {
	      y++;
	      error = error + deltax;
	      if (deltay <= error)
		{
		  x--;
		  error = error - deltay;
		}
	    }
	  else
	    {
	      x--;
	      error = error + deltay;
	      if (deltax <= error)
		{
	  	  y++;
		  error = error - deltax;
		}
	    }
	  i++;
	}
    }
}

void FASTCALL
SEtoNW(SURFOBJ* OutputObj, CLIPOBJ* Clip,
       BRUSHOBJ* Brush, LONG x, LONG y, LONG deltax, LONG deltay,
       POINTL* Translate)
{
  int i;
  int error;
  BOOLEAN EnumMore;
  RECTL* ClipRect;
  RECT_ENUM RectEnum;
  ULONG Pixel = Brush->iSolidColor;
  LONG delta;

  CLIPOBJ_cEnumStart(Clip, FALSE, CT_RECTANGLES, CD_LEFTUP, 0);
  EnumMore = CLIPOBJ_bEnum(Clip, (ULONG) sizeof(RectEnum), (PVOID) &RectEnum);
  TranslateRects(&RectEnum, Translate);
  ClipRect = RectEnum.arcl;
  delta = max(deltax, deltay);
  i = 0;
  error = delta >> 1;
  while (i < delta && (ClipRect < RectEnum.arcl + RectEnum.c || EnumMore))
    {
      while ((ClipRect < RectEnum.arcl + RectEnum.c
              && (y < ClipRect->top
                  || (y < ClipRect->bottom && x < ClipRect->left)))
             || EnumMore)
	{
	  if (RectEnum.arcl + RectEnum.c <= ClipRect)
	    {
	      EnumMore = CLIPOBJ_bEnum(Clip, (ULONG) sizeof(RectEnum), (PVOID) &RectEnum);
	      TranslateRects(&RectEnum, Translate);
	      ClipRect = RectEnum.arcl;
	    }
	  else
	    {
	      ClipRect++;
	    }
	}
      if (ClipRect < RectEnum.arcl + RectEnum.c)
	{
	  if (x < ClipRect->right && y < ClipRect->bottom)
	    {
              DibFunctionsForBitmapFormat[OutputObj->iBitmapFormat].DIB_PutPixel(
	        OutputObj, x, y, Pixel);
	    }
	  if (deltax < deltay)
	    {
	      y--;
	      error = error + deltax;
	      if (deltay <= error)
		{
		  x--;
		  error = error - deltay;