1003 lines
35 KiB
C
1003 lines
35 KiB
C
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/******************************Module*Header*******************************\
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* Module Name: fillpath.c
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*
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* DrvFillPath
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*
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* Copyright (c) 1992-1994 Microsoft Corporation
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\**************************************************************************/
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// LATER identify convex polygons and special-case?
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// LATER identify vertical edges and special-case?
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// LATER move pointed-to variables into automatics in search loops
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// LATER punt to the engine with segmented framebuffer callbacks
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// LATER handle complex clipping
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// LATER coalesce rectangles
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#include "precomp.h"
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#define TAKING_ALLOC_STATS 0
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#define NUM_BUFFER_POINTS 96 // Maximum number of points in a path
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// for which we'll attempt to join
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// all the path records so that the
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// path may still be drawn by FastFill
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#if TAKING_ALLOC_STATS
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ULONG BufferHitInFillpath = 0;
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ULONG BufferMissInFillpath = 0;
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#endif
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// Describe a single non-horizontal edge of a path to fill.
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typedef struct _EDGE {
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PVOID pNext;
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INT iScansLeft;
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INT X;
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INT Y;
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INT iErrorTerm;
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INT iErrorAdjustUp;
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INT iErrorAdjustDown;
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INT iXWhole;
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INT iXDirection;
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INT iWindingDirection;
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} EDGE, *PEDGE;
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// Maximum number of rects we'll fill per call to
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// the fill code
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#define MAX_PATH_RECTS 50
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#define RECT_BYTES (MAX_PATH_RECTS * sizeof(RECTL))
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#define EDGE_BYTES (TMP_BUFFER_SIZE - RECT_BYTES)
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#define MAX_EDGES (EDGE_BYTES/sizeof(EDGE))
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//MIX translation table. Translates a mix 1-16, into an old style Rop 0-255.
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extern BYTE gaMix[];
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VOID AdvanceAETEdges(EDGE *pAETHead);
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VOID XSortAETEdges(EDGE *pAETHead);
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VOID MoveNewEdges(EDGE *pGETHead, EDGE *pAETHead, INT iCurrentY);
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EDGE * AddEdgeToGET(EDGE *pGETHead, EDGE *pFreeEdge, POINTFIX *ppfxEdgeStart,
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POINTFIX *ppfxEdgeEnd, RECTL *pClipRect);
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BOOL ConstructGET(EDGE *pGETHead, EDGE *pFreeEdges, PATHOBJ *ppo,
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PATHDATA *pd, BOOL bMore, RECTL *pClipRect);
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void AdjustErrorTerm(INT *pErrorTerm, INT iErrorAdjustUp, INT iErrorAdjustDown,
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INT yJump, INT *pXStart, INT iXDirection);
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/******************************Public*Routine******************************\
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* DrvFillPath
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*
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* Fill the specified path with the specified brush and ROP.
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*
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\**************************************************************************/
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BOOL DrvFillPath(
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SURFOBJ* pso,
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PATHOBJ* ppo,
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CLIPOBJ* pco,
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BRUSHOBJ* pbo,
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POINTL* pptlBrush,
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MIX mix,
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FLONG flOptions)
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{
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ULONG rop4;
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BYTE jClipping; // clipping type
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EDGE *pCurrentEdge;
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EDGE AETHead; // dummy head/tail node & sentinel for Active Edge Table
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EDGE *pAETHead; // pointer to AETHead
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EDGE GETHead; // dummy head/tail node & sentinel for Global Edge Table
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EDGE *pGETHead; // pointer to GETHead
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EDGE *pFreeEdges; // pointer to memory free for use to store edges
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ULONG ulNumRects; // # of rectangles to draw currently in rectangle list
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RECTL *prclRects; // pointer to start of rectangle draw list
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INT iCurrentY; // scan line for which we're currently scanning out the
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// fill
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ULONG ulHwForeMix; // Hardware foreground mix value
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ULONG ulHwBackMix; // Hardware background mix value
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RBRUSH_COLOR rbc; // Realized brush or solid color
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ULONG iSolidColor; // Copy of pbo->iSolidColor
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FNFILL *pfnFill; // Points to appropriate fill routine
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BOOL bMore;
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PATHDATA pd;
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RECTL ClipRect;
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PDEV *ppdev;
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DSURF *pdsurf;
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BOOL bRetVal=FALSE; // FALSE until proven TRUE
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BOOL bMemAlloced=FALSE; // FALSE until proven TRUE
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FLONG flFirstRecord;
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POINTFIX* pptfxTmp;
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ULONG cptfxTmp;
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POINTFIX aptfxBuf[NUM_BUFFER_POINTS];
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// Set up the clipping
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if (pco == (CLIPOBJ *) NULL) {
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// No CLIPOBJ provided, so we don't have to worry about clipping
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jClipping = DC_TRIVIAL;
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} else {
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// Use the CLIPOBJ-provided clipping
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jClipping = pco->iDComplexity;
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}
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if (jClipping != DC_TRIVIAL) {
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if (jClipping != DC_RECT) {
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goto ReturnFalse; // there is complex clipping; let GDI fill the path
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}
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// Clip to the clip rectangle
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ClipRect = pco->rclBounds;
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} else {
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// So the y-clipping code doesn't do any clipping
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// /16 so we don't blow the values out when we scale up to GIQ
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ClipRect.top = (LONG_MIN + 1) / 16; // +1 to avoid compiler problem
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ClipRect.bottom = LONG_MAX / 16;
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}
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// There's nothing to do if there are only one or two points
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if (ppo->cCurves <= 2) {
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goto ReturnTrue;
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}
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// Pass the surface off to GDI if it's a device bitmap that we've
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// converted to a DIB:
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pdsurf = (DSURF*) pso->dhsurf;
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if (pdsurf->dt == DT_DIB)
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{
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return(EngFillPath(pdsurf->pso, ppo, pco, pbo, pptlBrush, mix,
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flOptions));
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}
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// We'll be drawing to the screen or an off-screen DFB; copy the surface's
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// offset now so that we won't need to refer to the DSURF again:
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ppdev = (PDEV*) pso->dhpdev;
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ppdev->xOffset = pdsurf->poh->x;
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ppdev->yOffset = pdsurf->poh->y;
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pfnFill = ppdev->pfnFillSolid;
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ulHwForeMix = gajHwMixFromMix[mix & 0xF];
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ulHwBackMix = gajHwMixFromMix[(mix >> 8) & 0xF];
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iSolidColor = 0; // Assume we won't need a pattern
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rop4 = (gaRop3FromMix[mix >> 8] << 8) | gaRop3FromMix[mix & 0xff];
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if ((((rop4 & 0xff00) >> 8) != (rop4 & 0x00ff)) ||
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((((rop4 >> 4) ^ (rop4)) & 0xf0f) != 0)) // Only do if we need a pattern
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{
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iSolidColor = pbo->iSolidColor;
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rbc.iSolidColor = iSolidColor;
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if (rbc.iSolidColor == -1)
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{
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ppdev->bRealizeTransparent = (ulHwForeMix != ulHwBackMix);
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rbc.prb = pbo->pvRbrush;
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if (rbc.prb == NULL)
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{
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rbc.prb = BRUSHOBJ_pvGetRbrush(pbo);
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if (rbc.prb == NULL)
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return(FALSE);
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}
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pfnFill = ppdev->pfnFillPat;
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}
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}
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// Enumerate path here first time to check for special
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// cases (rectangles and monotone polygons)
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// It is too difficult to determine interaction between
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// multiple paths, if there is more than one, skip this
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bMore = PATHOBJ_bEnum(ppo, &pd);
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if (jClipping == DC_TRIVIAL)
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{
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// Try going through the fast non-complex fill code. We'll have
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// to realize the brush first if we're going to handle a pattern:
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if (iSolidColor == -1)
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{
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#if !FASTFILL_PATTERNS
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goto SkipFastFill;
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#else
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// We handle patterns in 'pfnFastFill' only if we can use the S3
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// hardware patterns.
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if (!(ppdev->flCaps & CAPS_HW_PATTERNS))
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goto SkipFastFill;
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// Note: prb->pbe will be NULL and prb->ptlBrushOrg.x will be -1 the
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// first time an RBRUSH is used. So we have to check the
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// alignment *before* dereferencing prb->pbe...
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if ((rbc.prb->ptlBrushOrg.x != pptlBrush->x + ppdev->xOffset) ||
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(rbc.prb->ptlBrushOrg.y != pptlBrush->y + ppdev->yOffset) ||
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(rbc.prb->apbe[IBOARD(ppdev)]->prbVerify != rbc.prb) ||
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(rbc.prb->bTransparent != ppdev->bRealizeTransparent))
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{
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ppdev->pfnFastPatRealize(ppdev, rbc.prb, pptlBrush,
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ppdev->bRealizeTransparent);
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}
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#endif
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}
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if (bMore)
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{
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// FastFill only knows how to take a single contiguous buffer
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// of points. Unfortunately, GDI sometimes hands us paths
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// that are split over multiple path data records. Convex
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// figures such as Ellipses, Pies and RoundRects are almost
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// always given in multiple records. Since probably 90% of
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// multiple record paths could still be done by FastFill, for
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// those cases we simply copy the points into a contiguous
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// buffer...
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// First make sure that the entire path would fit in the
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// temporary buffer, and make sure the path isn't comprised
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// of more than one subpath:
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if ((ppo->cCurves >= NUM_BUFFER_POINTS) ||
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(pd.flags & PD_ENDSUBPATH))
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goto SkipFastFill;
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pptfxTmp = &aptfxBuf[0];
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RtlCopyMemory(pptfxTmp, pd.pptfx, sizeof(POINTFIX) * pd.count);
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pptfxTmp += pd.count;
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cptfxTmp = pd.count;
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flFirstRecord = pd.flags; // Remember PD_BEGINSUBPATH flag
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do {
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bMore = PATHOBJ_bEnum(ppo, &pd);
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RtlCopyMemory(pptfxTmp, pd.pptfx, sizeof(POINTFIX) * pd.count);
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cptfxTmp += pd.count;
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pptfxTmp += pd.count;
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} while (!(pd.flags & PD_ENDSUBPATH));
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// Fake up the path data record:
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pd.pptfx = &aptfxBuf[0];
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pd.count = cptfxTmp;
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pd.flags |= flFirstRecord;
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// If there's more than one subpath, we can't call FastFill:
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if (bMore)
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goto SkipFastFill;
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}
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if ((ppdev->pfnFastFill)(ppdev, pd.count, pd.pptfx, ulHwForeMix,
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ulHwBackMix, iSolidColor, rbc.prb))
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{
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return(TRUE);
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}
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}
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SkipFastFill:
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// Set up working storage in the temporary buffer
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prclRects = (RECTL*) ppdev->pvTmpBuffer; // storage for list of rectangles to draw
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if (!bMore) {
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RECTL *rectangle;
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INT cPoints = pd.count;
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// The count can't be less than three, because we got all the edges
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// in this subpath, and above we checked that there were at least
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// three edges
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// If the count is four, check to see if the polygon is really a
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// rectangle since we can really speed that up. We'll also check for
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// five with the first and last points the same, because under Win 3.1,
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// it was required to close polygons
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if ((cPoints == 4) ||
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((cPoints == 5) &&
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(pd.pptfx[0].x == pd.pptfx[4].x) &&
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(pd.pptfx[0].y == pd.pptfx[4].y))) {
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rectangle = prclRects;
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/* we have to start somewhere so assume that most
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applications specify the top left point first
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we want to check that the first two points are
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either vertically or horizontally aligned. if
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they are then we check that the last point [3]
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is either horizontally or vertically aligned,
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and finally that the 3rd point [2] is aligned
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with both the first point and the last point */
|
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#define FIX_SHIFT 4L
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#define FIX_MASK (- (1 << FIX_SHIFT))
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rectangle->top = pd.pptfx[0].y - 1 & FIX_MASK;
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rectangle->left = pd.pptfx[0].x - 1 & FIX_MASK;
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rectangle->right = pd.pptfx[1].x - 1 & FIX_MASK;
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if (rectangle->left ^ rectangle->right) {
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if (rectangle->top ^ (pd.pptfx[1].y - 1 & FIX_MASK))
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goto not_rectangle;
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if (rectangle->left ^ (pd.pptfx[3].x - 1 & FIX_MASK))
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goto not_rectangle;
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if (rectangle->right ^ (pd.pptfx[2].x - 1 & FIX_MASK))
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goto not_rectangle;
|
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rectangle->bottom = pd.pptfx[2].y - 1 & FIX_MASK;
|
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if (rectangle->bottom ^ (pd.pptfx[3].y - 1 & FIX_MASK))
|
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goto not_rectangle;
|
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}
|
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else {
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if (rectangle->top ^ (pd.pptfx[3].y - 1 & FIX_MASK))
|
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goto not_rectangle;
|
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rectangle->bottom = pd.pptfx[1].y - 1 & FIX_MASK;
|
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if (rectangle->bottom ^ (pd.pptfx[2].y - 1 & FIX_MASK))
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goto not_rectangle;
|
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rectangle->right = pd.pptfx[2].x - 1 & FIX_MASK;
|
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if (rectangle->right ^ (pd.pptfx[3].x - 1 & FIX_MASK))
|
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goto not_rectangle;
|
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|
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}
|
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|
||
|
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/* if the left is greater than the right then
|
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|
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swap them so the blt code doesn't wig out */
|
||
|
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|
||
|
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if (rectangle->left > rectangle->right) {
|
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|
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FIX temp;
|
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|
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|
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temp = rectangle->left;
|
||
|
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rectangle->left = rectangle->right;
|
||
|
|
rectangle->right = temp;
|
||
|
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}
|
||
|
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else {
|
||
|
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|
||
|
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/* if left == right there's nothing to draw */
|
||
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|
||
|
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if (rectangle->left == rectangle->right) {
|
||
|
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goto ReturnTrue;
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
/* shift the values to get pixel coordinates */
|
||
|
|
|
||
|
|
rectangle->left = (rectangle->left >> FIX_SHIFT) + 1;
|
||
|
|
rectangle->right = (rectangle->right >> FIX_SHIFT) + 1;
|
||
|
|
|
||
|
|
if (rectangle->top > rectangle->bottom) {
|
||
|
|
FIX temp;
|
||
|
|
|
||
|
|
temp = rectangle->top;
|
||
|
|
rectangle->top = rectangle->bottom;
|
||
|
|
rectangle->bottom = temp;
|
||
|
|
}
|
||
|
|
else {
|
||
|
|
if (rectangle->top == rectangle->bottom) {
|
||
|
|
goto ReturnTrue;
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
/* shift the values to get pixel coordinates */
|
||
|
|
|
||
|
|
rectangle->top = (rectangle->top >> FIX_SHIFT) + 1;
|
||
|
|
rectangle->bottom = (rectangle->bottom >> FIX_SHIFT) + 1;
|
||
|
|
|
||
|
|
// Finally, check for clipping
|
||
|
|
if (jClipping == DC_RECT) {
|
||
|
|
// Clip to the clip rectangle
|
||
|
|
if (!bIntersect(rectangle, &ClipRect, rectangle)) {
|
||
|
|
// Totally clipped, nothing to do
|
||
|
|
goto ReturnTrue;
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
/* if we get here then the polygon is a rectangle,
|
||
|
|
set count to 1 and goto bottom to draw it */
|
||
|
|
|
||
|
|
ulNumRects = 1;
|
||
|
|
goto draw_remaining_rectangles;
|
||
|
|
}
|
||
|
|
|
||
|
|
not_rectangle:
|
||
|
|
|
||
|
|
;
|
||
|
|
|
||
|
|
}
|
||
|
|
|
||
|
|
// Do we have enough memory for all the edges?
|
||
|
|
// LATER does cCurves include closure?
|
||
|
|
if (ppo->cCurves > MAX_EDGES) {
|
||
|
|
#if TAKING_ALLOC_STATS
|
||
|
|
BufferMissInFillpath++;
|
||
|
|
#endif
|
||
|
|
//
|
||
|
|
// try to allocate enough memory
|
||
|
|
//
|
||
|
|
pFreeEdges = (EDGE *) EngAllocMem(0, (ppo->cCurves * sizeof(EDGE)), ALLOC_TAG);
|
||
|
|
|
||
|
|
if (pFreeEdges == NULL)
|
||
|
|
{
|
||
|
|
goto ReturnFalse; // too many edges; let GDI fill the path
|
||
|
|
}
|
||
|
|
else
|
||
|
|
{
|
||
|
|
bMemAlloced = TRUE;
|
||
|
|
}
|
||
|
|
}
|
||
|
|
else {
|
||
|
|
#if TAKING_ALLOC_STATS
|
||
|
|
BufferHitInFillpath++;
|
||
|
|
#endif
|
||
|
|
pFreeEdges = (EDGE*) ((BYTE*) ppdev->pvTmpBuffer + RECT_BYTES);
|
||
|
|
// use our handy temporary buffer (it's big enough)
|
||
|
|
}
|
||
|
|
|
||
|
|
// Initialize an empty list of rectangles to fill
|
||
|
|
ulNumRects = 0;
|
||
|
|
|
||
|
|
// Enumerate the path edges and build a Global Edge Table (GET) from them
|
||
|
|
// in YX-sorted order.
|
||
|
|
pGETHead = &GETHead;
|
||
|
|
if (!ConstructGET(pGETHead, pFreeEdges, ppo, &pd, bMore, &ClipRect)) {
|
||
|
|
goto ReturnFalse; // outside GDI's 2**27 range
|
||
|
|
}
|
||
|
|
|
||
|
|
// Create an empty AET with the head node also a tail sentinel
|
||
|
|
pAETHead = &AETHead;
|
||
|
|
AETHead.pNext = pAETHead; // mark that the AET is empty
|
||
|
|
AETHead.X = 0x7FFFFFFF; // this is greater than any valid X value, so
|
||
|
|
// searches will always terminate
|
||
|
|
|
||
|
|
// Top scan of polygon is the top of the first edge we come to
|
||
|
|
iCurrentY = ((EDGE *)GETHead.pNext)->Y;
|
||
|
|
|
||
|
|
// Loop through all the scans in the polygon, adding edges from the GET to
|
||
|
|
// the Active Edge Table (AET) as we come to their starts, and scanning out
|
||
|
|
// the AET at each scan into a rectangle list. Each time it fills up, the
|
||
|
|
// rectangle list is passed to the filling routine, and then once again at
|
||
|
|
// the end if any rectangles remain undrawn. We continue so long as there
|
||
|
|
// are edges to be scanned out
|
||
|
|
while (1) {
|
||
|
|
|
||
|
|
// Advance the edges in the AET one scan, discarding any that have
|
||
|
|
// reached the end (if there are any edges in the AET)
|
||
|
|
if (AETHead.pNext != pAETHead) {
|
||
|
|
AdvanceAETEdges(pAETHead);
|
||
|
|
}
|
||
|
|
|
||
|
|
// If the AET is empty, done if the GET is empty, else jump ahead to
|
||
|
|
// the next edge in the GET; if the AET isn't empty, re-sort the AET
|
||
|
|
if (AETHead.pNext == pAETHead) {
|
||
|
|
if (GETHead.pNext == pGETHead) {
|
||
|
|
// Done if there are no edges in either the AET or the GET
|
||
|
|
break;
|
||
|
|
}
|
||
|
|
// There are no edges in the AET, so jump ahead to the next edge in
|
||
|
|
// the GET
|
||
|
|
iCurrentY = ((EDGE *)GETHead.pNext)->Y;
|
||
|
|
} else {
|
||
|
|
// Re-sort the edges in the AET by X coordinate, if there are at
|
||
|
|
// least two edges in the AET (there could be one edge if the
|
||
|
|
// balancing edge hasn't yet been added from the GET)
|
||
|
|
if (((EDGE *)AETHead.pNext)->pNext != pAETHead) {
|
||
|
|
XSortAETEdges(pAETHead);
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
// Move any new edges that start on this scan from the GET to the AET;
|
||
|
|
// bother calling only if there's at least one edge to add
|
||
|
|
if (((EDGE *)GETHead.pNext)->Y == iCurrentY) {
|
||
|
|
MoveNewEdges(pGETHead, pAETHead, iCurrentY);
|
||
|
|
}
|
||
|
|
|
||
|
|
// Scan the AET into rectangles to fill (there's always at least one
|
||
|
|
// edge pair in the AET)
|
||
|
|
pCurrentEdge = AETHead.pNext; // point to the first edge
|
||
|
|
do {
|
||
|
|
|
||
|
|
INT iLeftEdge;
|
||
|
|
|
||
|
|
// The left edge of any given edge pair is easy to find; it's just
|
||
|
|
// wherever we happen to be currently
|
||
|
|
iLeftEdge = pCurrentEdge->X;
|
||
|
|
|
||
|
|
// Find the matching right edge according to the current fill rule
|
||
|
|
if ((flOptions & FP_WINDINGMODE) != 0) {
|
||
|
|
|
||
|
|
INT iWindingCount;
|
||
|
|
|
||
|
|
// Do winding fill; scan across until we've found equal numbers
|
||
|
|
// of up and down edges
|
||
|
|
iWindingCount = pCurrentEdge->iWindingDirection;
|
||
|
|
do {
|
||
|
|
pCurrentEdge = pCurrentEdge->pNext;
|
||
|
|
iWindingCount += pCurrentEdge->iWindingDirection;
|
||
|
|
} while (iWindingCount != 0);
|
||
|
|
} else {
|
||
|
|
// Odd-even fill; the next edge is the matching right edge
|
||
|
|
pCurrentEdge = pCurrentEdge->pNext;
|
||
|
|
}
|
||
|
|
|
||
|
|
// See if the resulting span encompasses at least one pixel, and
|
||
|
|
// add it to the list of rectangles to draw if so
|
||
|
|
if (iLeftEdge < pCurrentEdge->X) {
|
||
|
|
|
||
|
|
// We've got an edge pair to add to the list to be filled; see
|
||
|
|
// if there's room for one more rectangle
|
||
|
|
if (ulNumRects >= MAX_PATH_RECTS) {
|
||
|
|
// No more room; draw the rectangles in the list and reset
|
||
|
|
// it to empty
|
||
|
|
|
||
|
|
(*pfnFill)(ppdev, ulNumRects, prclRects, ulHwForeMix,
|
||
|
|
ulHwBackMix, rbc, pptlBrush);
|
||
|
|
|
||
|
|
// Reset the list to empty
|
||
|
|
ulNumRects = 0;
|
||
|
|
}
|
||
|
|
|
||
|
|
// Add the rectangle representing the current edge pair
|
||
|
|
if (jClipping == DC_RECT) {
|
||
|
|
// Clipped
|
||
|
|
// Clip to left
|
||
|
|
prclRects[ulNumRects].left = max(iLeftEdge, ClipRect.left);
|
||
|
|
// Clip to right
|
||
|
|
prclRects[ulNumRects].right =
|
||
|
|
min(pCurrentEdge->X, ClipRect.right);
|
||
|
|
// Draw only if not fully clipped
|
||
|
|
if (prclRects[ulNumRects].left <
|
||
|
|
prclRects[ulNumRects].right) {
|
||
|
|
prclRects[ulNumRects].top = iCurrentY;
|
||
|
|
prclRects[ulNumRects].bottom = iCurrentY+1;
|
||
|
|
ulNumRects++;
|
||
|
|
}
|
||
|
|
}
|
||
|
|
else
|
||
|
|
{
|
||
|
|
// Unclipped
|
||
|
|
prclRects[ulNumRects].top = iCurrentY;
|
||
|
|
prclRects[ulNumRects].bottom = iCurrentY+1;
|
||
|
|
prclRects[ulNumRects].left = iLeftEdge;
|
||
|
|
prclRects[ulNumRects].right = pCurrentEdge->X;
|
||
|
|
ulNumRects++;
|
||
|
|
}
|
||
|
|
}
|
||
|
|
} while ((pCurrentEdge = pCurrentEdge->pNext) != pAETHead);
|
||
|
|
|
||
|
|
iCurrentY++; // next scan
|
||
|
|
}
|
||
|
|
|
||
|
|
/* draw the remaining rectangles, if there are any */
|
||
|
|
|
||
|
|
draw_remaining_rectangles:
|
||
|
|
|
||
|
|
if (ulNumRects > 0) {
|
||
|
|
(*pfnFill)(ppdev, ulNumRects, prclRects, ulHwForeMix, ulHwBackMix,
|
||
|
|
rbc, pptlBrush);
|
||
|
|
}
|
||
|
|
|
||
|
|
ReturnTrue:
|
||
|
|
bRetVal = TRUE; // done successfully
|
||
|
|
|
||
|
|
ReturnFalse:
|
||
|
|
|
||
|
|
// bRetVal is originally false. If you jumped to ReturnFalse from somewhere,
|
||
|
|
// then it will remain false, and be returned.
|
||
|
|
|
||
|
|
if (bMemAlloced)
|
||
|
|
{
|
||
|
|
//
|
||
|
|
// we did allocate memory, so release it
|
||
|
|
//
|
||
|
|
EngFreeMem (pFreeEdges);
|
||
|
|
}
|
||
|
|
|
||
|
|
return(bRetVal);
|
||
|
|
}
|
||
|
|
|
||
|
|
// Advance the edges in the AET to the next scan, dropping any for which we've
|
||
|
|
// done all scans. Assumes there is at least one edge in the AET.
|
||
|
|
VOID AdvanceAETEdges(EDGE *pAETHead)
|
||
|
|
{
|
||
|
|
EDGE *pLastEdge, *pCurrentEdge;
|
||
|
|
|
||
|
|
pLastEdge = pAETHead;
|
||
|
|
pCurrentEdge = pLastEdge->pNext;
|
||
|
|
do {
|
||
|
|
|
||
|
|
// Count down this edge's remaining scans
|
||
|
|
if (--pCurrentEdge->iScansLeft == 0) {
|
||
|
|
// We've done all scans for this edge; drop this edge from the AET
|
||
|
|
pLastEdge->pNext = pCurrentEdge->pNext;
|
||
|
|
} else {
|
||
|
|
// Advance the edge's X coordinate for a 1-scan Y advance
|
||
|
|
// Advance by the minimum amount
|
||
|
|
pCurrentEdge->X += pCurrentEdge->iXWhole;
|
||
|
|
// Advance the error term and see if we got one extra pixel this
|
||
|
|
// time
|
||
|
|
pCurrentEdge->iErrorTerm += pCurrentEdge->iErrorAdjustUp;
|
||
|
|
if (pCurrentEdge->iErrorTerm >= 0) {
|
||
|
|
// The error term turned over, so adjust the error term and
|
||
|
|
// advance the extra pixel
|
||
|
|
pCurrentEdge->iErrorTerm -= pCurrentEdge->iErrorAdjustDown;
|
||
|
|
pCurrentEdge->X += pCurrentEdge->iXDirection;
|
||
|
|
}
|
||
|
|
|
||
|
|
pLastEdge = pCurrentEdge;
|
||
|
|
}
|
||
|
|
} while ((pCurrentEdge = pLastEdge->pNext) != pAETHead);
|
||
|
|
}
|
||
|
|
|
||
|
|
// X-sort the AET, because the edges may have moved around relative to
|
||
|
|
// one another when we advanced them. We'll use a multipass bubble
|
||
|
|
// sort, which is actually okay for this application because edges
|
||
|
|
// rarely move relative to one another, so we usually do just one pass.
|
||
|
|
// Also, this makes it easy to keep just a singly-linked list. Assumes there
|
||
|
|
// are at least two edges in the AET.
|
||
|
|
VOID XSortAETEdges(EDGE *pAETHead)
|
||
|
|
{
|
||
|
|
BOOL bEdgesSwapped;
|
||
|
|
EDGE *pLastEdge, *pCurrentEdge, *pNextEdge;
|
||
|
|
|
||
|
|
do {
|
||
|
|
|
||
|
|
bEdgesSwapped = FALSE;
|
||
|
|
pLastEdge = pAETHead;
|
||
|
|
pCurrentEdge = pLastEdge->pNext;
|
||
|
|
pNextEdge = pCurrentEdge->pNext;
|
||
|
|
|
||
|
|
do {
|
||
|
|
if (pNextEdge->X < pCurrentEdge->X) {
|
||
|
|
|
||
|
|
// Next edge is to the left of the current edge; swap them
|
||
|
|
pLastEdge->pNext = pNextEdge;
|
||
|
|
pCurrentEdge->pNext = pNextEdge->pNext;
|
||
|
|
pNextEdge->pNext = pCurrentEdge;
|
||
|
|
bEdgesSwapped = TRUE;
|
||
|
|
pCurrentEdge = pNextEdge; // continue sorting before the edge
|
||
|
|
// we just swapped; it might move
|
||
|
|
// farther yet
|
||
|
|
}
|
||
|
|
pLastEdge = pCurrentEdge;
|
||
|
|
pCurrentEdge = pLastEdge->pNext;
|
||
|
|
} while ((pNextEdge = pCurrentEdge->pNext) != pAETHead);
|
||
|
|
} while (bEdgesSwapped);
|
||
|
|
}
|
||
|
|
|
||
|
|
// Moves all edges that start on the current scan from the GET to the AET in
|
||
|
|
// X-sorted order. Parameters are pointer to head of GET and pointer to dummy
|
||
|
|
// edge at head of AET, plus current scan line. Assumes there's at least one
|
||
|
|
// edge to be moved.
|
||
|
|
VOID MoveNewEdges(EDGE *pGETHead, EDGE *pAETHead, INT iCurrentY)
|
||
|
|
{
|
||
|
|
EDGE *pCurrentEdge = pAETHead;
|
||
|
|
EDGE *pGETNext = pGETHead->pNext;
|
||
|
|
|
||
|
|
do {
|
||
|
|
|
||
|
|
// Scan through the AET until the X-sorted insertion point for this
|
||
|
|
// edge is found. We can continue from where the last search left
|
||
|
|
// off because the edges in the GET are in X sorted order, as is
|
||
|
|
// the AET. The search always terminates because the AET sentinel
|
||
|
|
// is greater than any valid X
|
||
|
|
while (pGETNext->X > ((EDGE *)pCurrentEdge->pNext)->X) {
|
||
|
|
pCurrentEdge = pCurrentEdge->pNext;
|
||
|
|
}
|
||
|
|
|
||
|
|
// We've found the insertion point; add the GET edge to the AET, and
|
||
|
|
// remove it from the GET
|
||
|
|
pGETHead->pNext = pGETNext->pNext;
|
||
|
|
pGETNext->pNext = pCurrentEdge->pNext;
|
||
|
|
pCurrentEdge->pNext = pGETNext;
|
||
|
|
pCurrentEdge = pGETNext; // continue insertion search for the next
|
||
|
|
// GET edge after the edge we just added
|
||
|
|
pGETNext = pGETHead->pNext;
|
||
|
|
|
||
|
|
} while (pGETNext->Y == iCurrentY);
|
||
|
|
}
|
||
|
|
|
||
|
|
|
||
|
|
|
||
|
|
|
||
|
|
|
||
|
|
// Build the Global Edge Table from the path. There must be enough memory in
|
||
|
|
// the free edge area to hold all edges. The GET is constructed in Y-X order,
|
||
|
|
// and has a head/tail/sentinel node at pGETHead.
|
||
|
|
|
||
|
|
BOOL ConstructGET(
|
||
|
|
EDGE *pGETHead,
|
||
|
|
EDGE *pFreeEdges,
|
||
|
|
PATHOBJ *ppo,
|
||
|
|
PATHDATA *pd,
|
||
|
|
BOOL bMore,
|
||
|
|
RECTL *pClipRect)
|
||
|
|
{
|
||
|
|
POINTFIX pfxPathStart; // point that started the current subpath
|
||
|
|
POINTFIX pfxPathPrevious; // point before the current point in a subpath;
|
||
|
|
// starts the current edge
|
||
|
|
|
||
|
|
/* Create an empty GET with the head node also a tail sentinel */
|
||
|
|
|
||
|
|
pGETHead->pNext = pGETHead; // mark that the GET is empty
|
||
|
|
pGETHead->Y = 0x7FFFFFFF; // this is greater than any valid Y value, so
|
||
|
|
// searches will always terminate
|
||
|
|
|
||
|
|
/* PATHOBJ_vEnumStart is implicitly performed by engine
|
||
|
|
already and first path is enumerated by the caller */
|
||
|
|
|
||
|
|
next_subpath:
|
||
|
|
|
||
|
|
/* Make sure the PATHDATA is not empty (is this necessary) */
|
||
|
|
|
||
|
|
if (pd->count != 0) {
|
||
|
|
|
||
|
|
/* If first point starts a subpath, remember it as such
|
||
|
|
and go on to the next point, so we can get an edge */
|
||
|
|
|
||
|
|
if (pd->flags & PD_BEGINSUBPATH) {
|
||
|
|
|
||
|
|
/* the first point starts the subpath; remember it */
|
||
|
|
|
||
|
|
|
||
|
|
pfxPathStart = *pd->pptfx; /* the subpath starts here */
|
||
|
|
pfxPathPrevious = *pd->pptfx; /* this points starts the next edge */
|
||
|
|
pd->pptfx++; /* advance to the next point */
|
||
|
|
pd->count--; /* count off this point */
|
||
|
|
}
|
||
|
|
|
||
|
|
|
||
|
|
/* add edges in PATHDATA to GET, in Y-X sorted order */
|
||
|
|
|
||
|
|
while (pd->count--) {
|
||
|
|
if ((pFreeEdges =
|
||
|
|
AddEdgeToGET(pGETHead, pFreeEdges, &pfxPathPrevious, pd->pptfx,
|
||
|
|
pClipRect)) == NULL) {
|
||
|
|
goto ReturnFalse;
|
||
|
|
}
|
||
|
|
pfxPathPrevious = *pd->pptfx; /* current point becomes previous */
|
||
|
|
pd->pptfx++; /* advance to the next point */
|
||
|
|
}
|
||
|
|
|
||
|
|
|
||
|
|
/* If last point ends the subpath, insert the edge that
|
||
|
|
connects to first point (is this built in already?) */
|
||
|
|
|
||
|
|
if (pd->flags & PD_ENDSUBPATH) {
|
||
|
|
if ((pFreeEdges = AddEdgeToGET(pGETHead, pFreeEdges, &pfxPathPrevious,
|
||
|
|
&pfxPathStart, pClipRect)) == NULL) {
|
||
|
|
goto ReturnFalse;
|
||
|
|
}
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
/* the initial loop conditions preclude a do, while or for */
|
||
|
|
|
||
|
|
if (bMore) {
|
||
|
|
bMore = PATHOBJ_bEnum(ppo, pd);
|
||
|
|
goto next_subpath;
|
||
|
|
}
|
||
|
|
|
||
|
|
return(TRUE); // done successfully
|
||
|
|
|
||
|
|
ReturnFalse:
|
||
|
|
return(FALSE); // failed
|
||
|
|
}
|
||
|
|
|
||
|
|
// Adds the edge described by the two passed-in points to the Global Edge
|
||
|
|
// Table, if the edge spans at least one pixel vertically.
|
||
|
|
EDGE * AddEdgeToGET(EDGE *pGETHead, EDGE *pFreeEdge,
|
||
|
|
POINTFIX *ppfxEdgeStart, POINTFIX *ppfxEdgeEnd, RECTL *pClipRect)
|
||
|
|
{
|
||
|
|
INT iYStart, iYEnd, iXStart, iXEnd, iYHeight, iXWidth;
|
||
|
|
INT yJump, yTop;
|
||
|
|
|
||
|
|
// Set the winding-rule direction of the edge, and put the endpoints in
|
||
|
|
// top-to-bottom order
|
||
|
|
iYHeight = ppfxEdgeEnd->y - ppfxEdgeStart->y;
|
||
|
|
if (iYHeight == 0) {
|
||
|
|
return(pFreeEdge); // zero height; ignore this edge
|
||
|
|
} else if (iYHeight >= 0) {
|
||
|
|
iXStart = ppfxEdgeStart->x;
|
||
|
|
iYStart = ppfxEdgeStart->y;
|
||
|
|
iXEnd = ppfxEdgeEnd->x;
|
||
|
|
iYEnd = ppfxEdgeEnd->y;
|
||
|
|
pFreeEdge->iWindingDirection = 1;
|
||
|
|
} else {
|
||
|
|
iYHeight = -iYHeight;
|
||
|
|
iXEnd = ppfxEdgeStart->x;
|
||
|
|
iYEnd = ppfxEdgeStart->y;
|
||
|
|
iXStart = ppfxEdgeEnd->x;
|
||
|
|
iYStart = ppfxEdgeEnd->y;
|
||
|
|
pFreeEdge->iWindingDirection = -1;
|
||
|
|
}
|
||
|
|
|
||
|
|
if (iYHeight & 0x80000000) {
|
||
|
|
return(NULL); // too large; outside 2**27 GDI range
|
||
|
|
}
|
||
|
|
|
||
|
|
// Set the error term and adjustment factors, all in GIQ coordinates for
|
||
|
|
// now
|
||
|
|
iXWidth = iXEnd - iXStart;
|
||
|
|
if (iXWidth >= 0) {
|
||
|
|
// Left to right, so we change X as soon as we move at all
|
||
|
|
pFreeEdge->iXDirection = 1;
|
||
|
|
pFreeEdge->iErrorTerm = -1;
|
||
|
|
} else {
|
||
|
|
// Right to left, so we don't change X until we've moved a full GIQ
|
||
|
|
// coordinate
|
||
|
|
iXWidth = -iXWidth;
|
||
|
|
pFreeEdge->iXDirection = -1;
|
||
|
|
pFreeEdge->iErrorTerm = -iYHeight;
|
||
|
|
}
|
||
|
|
|
||
|
|
if (iXWidth & 0x80000000) {
|
||
|
|
return(NULL); // too large; outside 2**27 GDI range
|
||
|
|
}
|
||
|
|
|
||
|
|
if (iXWidth >= iYHeight) {
|
||
|
|
// Calculate base run length (minimum distance advanced in X for a 1-
|
||
|
|
// scan advance in Y)
|
||
|
|
pFreeEdge->iXWhole = iXWidth / iYHeight;
|
||
|
|
// Add sign back into base run length if going right to left
|
||
|
|
if (pFreeEdge->iXDirection == -1) {
|
||
|
|
pFreeEdge->iXWhole = -pFreeEdge->iXWhole;
|
||
|
|
}
|
||
|
|
pFreeEdge->iErrorAdjustUp = iXWidth % iYHeight;
|
||
|
|
} else {
|
||
|
|
// Base run length is 0, because line is closer to vertical than
|
||
|
|
// horizontal
|
||
|
|
pFreeEdge->iXWhole = 0;
|
||
|
|
pFreeEdge->iErrorAdjustUp = iXWidth;
|
||
|
|
}
|
||
|
|
pFreeEdge->iErrorAdjustDown = iYHeight;
|
||
|
|
|
||
|
|
// Calculate the number of pixels spanned by this edge, accounting for
|
||
|
|
// clipping
|
||
|
|
|
||
|
|
// Top true pixel scan in GIQ coordinates
|
||
|
|
// Shifting to divide and multiply by 16 is okay because the clip rect
|
||
|
|
// always contains positive numbers
|
||
|
|
yTop = max(pClipRect->top << 4, (iYStart + 15) & ~0x0F);
|
||
|
|
pFreeEdge->Y = yTop >> 4; // initial scan line on which to fill edge
|
||
|
|
|
||
|
|
// Calculate # of scans to actually fill, accounting for clipping
|
||
|
|
if ((pFreeEdge->iScansLeft = min(pClipRect->bottom, ((iYEnd + 15) >> 4))
|
||
|
|
- pFreeEdge->Y) <= 0) {
|
||
|
|
|
||
|
|
return(pFreeEdge); // no pixels at all are spanned, so we can
|
||
|
|
// ignore this edge
|
||
|
|
}
|
||
|
|
|
||
|
|
// If the edge doesn't start on a pixel scan (that is, it starts at a
|
||
|
|
// fractional GIQ coordinate), advance it to the first pixel scan it
|
||
|
|
// intersects. Ditto if there's top clipping. Also clip to the bottom if
|
||
|
|
// needed
|
||
|
|
|
||
|
|
if (iYStart != yTop) {
|
||
|
|
// Jump ahead by the Y distance in GIQ coordinates to the first pixel
|
||
|
|
// to draw
|
||
|
|
yJump = yTop - iYStart;
|
||
|
|
|
||
|
|
// Advance x the minimum amount for the number of scans traversed
|
||
|
|
iXStart += pFreeEdge->iXWhole * yJump;
|
||
|
|
|
||
|
|
AdjustErrorTerm(&pFreeEdge->iErrorTerm, pFreeEdge->iErrorAdjustUp,
|
||
|
|
pFreeEdge->iErrorAdjustDown, yJump, &iXStart,
|
||
|
|
pFreeEdge->iXDirection);
|
||
|
|
}
|
||
|
|
// Turn the calculations into pixel rather than GIQ calculations
|
||
|
|
|
||
|
|
// Move the X coordinate to the nearest pixel, and adjust the error term
|
||
|
|
// accordingly
|
||
|
|
// Dividing by 16 with a shift is okay because X is always positive
|
||
|
|
pFreeEdge->X = (iXStart + 15) >> 4; // convert from GIQ to pixel coordinates
|
||
|
|
|
||
|
|
// LATER adjust only if needed (if prestepped above)?
|
||
|
|
if (pFreeEdge->iXDirection == 1) {
|
||
|
|
// Left to right
|
||
|
|
pFreeEdge->iErrorTerm -= pFreeEdge->iErrorAdjustDown *
|
||
|
|
(((iXStart + 15) & ~0x0F) - iXStart);
|
||
|
|
} else {
|
||
|
|
// Right to left
|
||
|
|
pFreeEdge->iErrorTerm -= pFreeEdge->iErrorAdjustDown *
|
||
|
|
((iXStart - 1) & 0x0F);
|
||
|
|
}
|
||
|
|
|
||
|
|
// Scale the error term down 16 times to switch from GIQ to pixels.
|
||
|
|
// Shifts work to do the multiplying because these values are always
|
||
|
|
// non-negative
|
||
|
|
pFreeEdge->iErrorTerm >>= 4;
|
||
|
|
|
||
|
|
// Insert the edge into the GET in YX-sorted order. The search always ends
|
||
|
|
// because the GET has a sentinel with a greater-than-possible Y value
|
||
|
|
while ((pFreeEdge->Y > ((EDGE *)pGETHead->pNext)->Y) ||
|
||
|
|
((pFreeEdge->Y == ((EDGE *)pGETHead->pNext)->Y) &&
|
||
|
|
(pFreeEdge->X > ((EDGE *)pGETHead->pNext)->X))) {
|
||
|
|
pGETHead = pGETHead->pNext;
|
||
|
|
}
|
||
|
|
|
||
|
|
pFreeEdge->pNext = pGETHead->pNext; // link the edge into the GET
|
||
|
|
pGETHead->pNext = pFreeEdge;
|
||
|
|
|
||
|
|
return(++pFreeEdge); // point to the next edge storage location for next
|
||
|
|
// time
|
||
|
|
}
|
||
|
|
|
||
|
|
// Adjust the error term for a skip ahead in y. This is in ASM because there's
|
||
|
|
// a multiply/divide that may involve a larger than 32-bit value.
|
||
|
|
|
||
|
|
void AdjustErrorTerm(INT *pErrorTerm, INT iErrorAdjustUp, INT iErrorAdjustDown,
|
||
|
|
INT yJump, INT *pXStart, INT iXDirection)
|
||
|
|
{
|
||
|
|
#if defined(_X86_) || defined(i386)
|
||
|
|
// Adjust the error term up by the number of y coordinates we'll skip
|
||
|
|
//*pErrorTerm += iErrorAdjustUp * yJump;
|
||
|
|
_asm mov ebx,pErrorTerm
|
||
|
|
_asm mov eax,iErrorAdjustUp
|
||
|
|
_asm mul yJump
|
||
|
|
_asm add eax,[ebx]
|
||
|
|
_asm adc edx,-1 // the error term starts out negative
|
||
|
|
|
||
|
|
// See if the error term turned over even once while skipping
|
||
|
|
//if (*pErrorTerm >= 0) {
|
||
|
|
_asm js short NoErrorTurnover
|
||
|
|
|
||
|
|
// # of times we'll turn over the error term and step an extra x
|
||
|
|
// coordinate while skipping
|
||
|
|
// NumAdjustDowns = (*pErrorTerm / iErrorAdjustDown) + 1;
|
||
|
|
_asm div iErrorAdjustDown
|
||
|
|
_asm inc eax
|
||
|
|
// Note that EDX is the remainder; (EDX - iErrorAdjustDown) is where
|
||
|
|
// the error term ends up ultimately
|
||
|
|
|
||
|
|
// Advance x appropriately for the # of times the error term
|
||
|
|
// turned over
|
||
|
|
// if (iXDirection == 1) {
|
||
|
|
// *pXStart += NumAdjustDowns;
|
||
|
|
// } else {
|
||
|
|
// *pXStart -= NumAdjustDowns;
|
||
|
|
// }
|
||
|
|
_asm mov ecx,pXStart
|
||
|
|
_asm cmp iXDirection,1
|
||
|
|
_asm jz short GoingRight
|
||
|
|
_asm neg eax
|
||
|
|
GoingRight:
|
||
|
|
_asm add [ecx],eax
|
||
|
|
|
||
|
|
// Adjust the error term down to its proper post-skip value
|
||
|
|
// *pErrorTerm -= iErrorAdjustDown * NumAdjustDowns;
|
||
|
|
_asm sub edx,iErrorAdjustDown
|
||
|
|
_asm mov eax,edx // put into EAX for storing to pErrorTerm next
|
||
|
|
// }
|
||
|
|
NoErrorTurnover:
|
||
|
|
_asm mov [ebx],eax
|
||
|
|
#else
|
||
|
|
INT NumAdjustDowns;
|
||
|
|
|
||
|
|
// Adjust the error term up by the number of y coordinates we'll skip
|
||
|
|
*pErrorTerm += iErrorAdjustUp * yJump;
|
||
|
|
|
||
|
|
// See if the error term turned over even once while skipping
|
||
|
|
if (*pErrorTerm >= 0) {
|
||
|
|
// # of times we'll turn over the error term and step an extra x
|
||
|
|
// coordinate while skipping
|
||
|
|
NumAdjustDowns = (*pErrorTerm / iErrorAdjustDown) + 1;
|
||
|
|
|
||
|
|
// Advance x appropriately for the # of times the error term
|
||
|
|
// turned over
|
||
|
|
if (iXDirection == 1) {
|
||
|
|
*pXStart += NumAdjustDowns;
|
||
|
|
} else {
|
||
|
|
*pXStart -= NumAdjustDowns;
|
||
|
|
}
|
||
|
|
|
||
|
|
// Adjust the error term down to its proper post-skip value
|
||
|
|
*pErrorTerm -= iErrorAdjustDown * NumAdjustDowns;
|
||
|
|
}
|
||
|
|
#endif
|
||
|
|
}
|
||
|
|
|