SkAnalyticCubicEdge Struct Reference

#include <SkAnalyticEdge.h>

Inheritance diagram for SkAnalyticCubicEdge:

Public Member Functions
bool	setCubic (const SkPoint pts[4], bool sortY=true)
bool	updateCubic (bool sortY=true)
void	keepContinuous ()
Public Member Functions inherited from SkAnalyticEdge
void	goY (SkFixed y)
void	goY (SkFixed y, int yShift)
void	saveXY (SkFixed x, SkFixed y, SkFixed dY)
bool	setLine (const SkPoint &p0, const SkPoint &p1)
bool	updateLine (SkFixed ax, SkFixed ay, SkFixed bx, SkFixed by, SkFixed slope)
bool	update (SkFixed last_y, bool sortY=true)

Public Attributes
SkCubicEdge	fCEdge
SkFixed	fSnappedY
Public Attributes inherited from SkAnalyticEdge
SkAnalyticEdge *	fNext
SkAnalyticEdge *	fPrev
SkAnalyticEdge *	fRiteE
SkFixed	fX
SkFixed	fDX
SkFixed	fUpperX
SkFixed	fY
SkFixed	fUpperY
SkFixed	fLowerY
SkFixed	fDY
SkFixed	fSavedX
SkFixed	fSavedY
SkFixed	fSavedDY
Type	fEdgeType
int8_t	fCurveCount
uint8_t	fCurveShift
uint8_t	fCubicDShift
int8_t	fWinding

Additional Inherited Members
Public Types inherited from SkAnalyticEdge
enum	Type { kLine_Type , kQuad_Type , kCubic_Type }
Static Public Member Functions inherited from SkAnalyticEdge
static SkFixed	SnapY (SkFixed y)
Static Public Attributes inherited from SkAnalyticEdge
static const int	kDefaultAccuracy = 2

Detailed Description

Definition at line 132 of file SkAnalyticEdge.h.

Member Function Documentation

keepContinuous()

void SkAnalyticCubicEdge::keepContinuous ( )

inline

Definition at line 139 of file SkAnalyticEdge.h.

                                 {
        SkASSERT(SkAbs32(fX - SkFixedMul(fDX, fY - SnapY(fCEdge.fCy)) - fCEdge.fCx) < SK_Fixed1);
        fCEdge.fCx = fX;
        fSnappedY = fY;
    }

setCubic()

bool SkAnalyticCubicEdge::setCubic	(	const SkPoint	pts[4],
		bool	sortY = true
	)

Definition at line 356 of file SkAnalyticEdge.cpp.

                                                                   {
    fRiteE = nullptr;
 
    if (!fCEdge.setCubicWithoutUpdate(pts, kDefaultAccuracy, sortY)) {
        return false;
    }
 
    fCEdge.fCx >>= kDefaultAccuracy;
    fCEdge.fCy >>= kDefaultAccuracy;
    fCEdge.fCDx >>= kDefaultAccuracy;
    fCEdge.fCDy >>= kDefaultAccuracy;
    fCEdge.fCDDx >>= kDefaultAccuracy;
    fCEdge.fCDDy >>= kDefaultAccuracy;
    fCEdge.fCDDDx >>= kDefaultAccuracy;
    fCEdge.fCDDDy >>= kDefaultAccuracy;
    fCEdge.fCLastX >>= kDefaultAccuracy;
    fCEdge.fCLastY >>= kDefaultAccuracy;
    fCEdge.fCy = SnapY(fCEdge.fCy);
    fCEdge.fCLastY = SnapY(fCEdge.fCLastY);
 
    fWinding = fCEdge.fWinding;
    fEdgeType = kCubic_Type;
    fCurveCount = fCEdge.fCurveCount;
    fCurveShift = fCEdge.fCurveShift;
    fCubicDShift = fCEdge.fCubicDShift;
 
    fSnappedY = fCEdge.fCy;
 
    return this->updateCubic(sortY);
}

updateCubic()

bool SkAnalyticCubicEdge::updateCubic

(

bool

sortY = true

)

Definition at line 387 of file SkAnalyticEdge.cpp.

                                                {
    int     success;
    int     count = fCurveCount;
    SkFixed oldx = fCEdge.fCx;
    SkFixed oldy = fCEdge.fCy;
    SkFixed newx, newy;
    const int ddshift = fCurveShift;
    const int dshift = fCubicDShift;
 
    SkASSERT(count < 0);
 
    do {
        if (++count < 0) {
            newx    = oldx + (fCEdge.fCDx >> dshift);
            fCEdge.fCDx    += fCEdge.fCDDx >> ddshift;
            fCEdge.fCDDx   += fCEdge.fCDDDx;
 
            newy    = oldy + (fCEdge.fCDy >> dshift);
            fCEdge.fCDy    += fCEdge.fCDDy >> ddshift;
            fCEdge.fCDDy   += fCEdge.fCDDDy;
        }
        else {    // last segment
            newx    = fCEdge.fCLastX;
            newy    = fCEdge.fCLastY;
        }
 
        // we want to say SkASSERT(oldy <= newy), but our finite fixedpoint
        // doesn't always achieve that, so we have to explicitly pin it here.
        if (sortY && newy < oldy) {
            newy = oldy;
        }
 
        SkFixed newSnappedY = SnapY(newy);
        // we want to SkASSERT(snappedNewY <= fCEdge.fCLastY), but our finite fixedpoint
        // doesn't always achieve that, so we have to explicitly pin it here.
        if (sortY && fCEdge.fCLastY < newSnappedY) {
            newSnappedY = fCEdge.fCLastY;
            count = 0;
        }
 
        SkFixed slope = SkFixedToFDot6(newSnappedY - fSnappedY) == 0
                        ? SK_MaxS32
                        : SkFDot6Div(SkFixedToFDot6(newx - oldx),
                                     SkFixedToFDot6(newSnappedY - fSnappedY));
 
        success = this->updateLine(oldx, fSnappedY, newx, newSnappedY, slope);
 
        oldx = newx;
        oldy = newy;
        fSnappedY = newSnappedY;
    } while (count < 0 && !success);
 
    fCEdge.fCx  = newx;
    fCEdge.fCy  = newy;
    fCurveCount = SkToS8(count);
    return success;
}

Member Data Documentation

fCEdge

SkCubicEdge SkAnalyticCubicEdge::fCEdge

Definition at line 133 of file SkAnalyticEdge.h.

fSnappedY

SkFixed SkAnalyticCubicEdge::fSnappedY

Definition at line 135 of file SkAnalyticEdge.h.

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The documentation for this struct was generated from the following files:

• third_party/skia/src/core/SkAnalyticEdge.h
• third_party/skia/src/core/SkAnalyticEdge.cpp