Revert of Analytic AntiAlias for Convex Shapes (patchset #14 id:260001 of https://codereview.chromium.org/2221103002/ )

Reason for revert:
Breaks iOS build.

Original issue's description:
> Implement AnalyticAA for convex shapes.
>
> Design doc: go/analyticAA
>
> A performance test can be found here: https://docs.google.com/a/google.com/spreadsheets/d/1n9LSjFzrQzx0hovFddWey0GSMXNRjl1oFuSypMlHWZk/edit?usp=sharing
>
> Our best case is filling big triangles, which according to our experiment has ~2.9x speedup. Our worst case is filling small ovals/circles, which has a ~1.06x slowdown.
>
> To see how our new algorithm changes the DM images, see: https://x20web.corp.google.com/~liyuqian/dmdiff/index.html
> The most significant changes are in convexpaths and analytic_antialias_convex
>
> BUG=skia:
> GOLD_TRYBOT_URL= https://gold.skia.org/search?issue=2221103002
>
> Committed: https://skia.googlesource.com/skia/+/7795822807478143120c33228b68d2ab3918af2c

TBR=reed@google.com,caryclark@google.com,liyuqian@google.com
# Skipping CQ checks because original CL landed less than 1 days ago.
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=skia:

Review-Url: https://codereview.chromium.org/2388213003

1 files changed, 0 insertions, 154 deletions

diff --git a/src/core/SkAnalyticEdge.h b/src/core/SkAnalyticEdge.h
deleted file mode 100644
index f4b23ba2b6..0000000000
--- a/src/core/SkAnalyticEdge.h
+++ /dev/null
@@ -1,154 +0,0 @@
-/*
- * Copyright 2006 The Android Open Source Project
- *
- * Use of this source code is governed by a BSD-style license that can be
- * found in the LICENSE file.
- */
-
-#ifndef SkAnalyticEdge_DEFINED
-#define SkAnalyticEdge_DEFINED
-
-#include "SkEdge.h"
-
-inline SkFixed SkFixedMul_lowprec(SkFixed a, SkFixed b) {
-    SkASSERT(((int64_t)a >> 8) * (b >> 8) <= SK_MaxS32);
-    return (a >> 8) * (b >> 8);
-}
-
-struct SkAnalyticEdge {
-    // Similar to SkEdge, the conic edges will be converted to quadratic edges
-    enum Type {
-        kLine_Type,
-        kQuad_Type,
-        kCubic_Type
-    };
-
-    SkAnalyticEdge* fNext;
-    SkAnalyticEdge* fPrev;
-
-    SkFixed fX;
-    SkFixed fDX;
-    SkFixed fUpperX;        // The x value when y = fUpperY
-    SkFixed fY;             // The current y
-    SkFixed fUpperY;        // The upper bound of y (our edge is from y = fUpperY to y = fLowerY)
-    SkFixed fLowerY;        // The lower bound of y (our edge is from y = fUpperY to y = fLowerY)
-    SkFixed fDY;            // abs(1/fDX); may be SK_MaxS32 when fDX is close to 0.
-                            // fDY is only used for blitting trapezoids.
-
-    int8_t  fCurveCount;    // only used by kQuad(+) and kCubic(-)
-    uint8_t fCurveShift;    // appled to all Dx/DDx/DDDx except for fCubicDShift exception
-    uint8_t fCubicDShift;   // applied to fCDx and fCDy only in cubic
-    int8_t  fWinding;       // 1 or -1
-
-    static const int kDefaultAccuracy = 2; // default accuracy for snapping
-
-    static inline SkFixed snapY(SkFixed y, int accuracy = kDefaultAccuracy) {
-        return SkFixedRoundToFixed(y << accuracy) >> accuracy;
-    }
-
-    // Update fX, fY of this edge so fY = y
-    inline void goY(SkFixed y) {
-        if (y == fY + SK_Fixed1) {
-            fX = fX + fDX;
-            fY = y;
-        } else if (y != fY) {
-            // Drop lower digits as our alpha only has 8 bits
-            // (fDX and y - fUpperY may be greater than SK_Fixed1)
-            fX = fUpperX + SkFixedMul_lowprec(fDX, y - fUpperY);
-            fY = y;
-        }
-    }
-
-    inline bool setLine(const SkPoint& p0, const SkPoint& p1, const SkIRect* clip = nullptr);
-    inline bool updateLine(SkFixed ax, SkFixed ay, SkFixed bx, SkFixed by, SkFixed slope);
-    void chopLineWithClip(const SkIRect& clip);
-
-    inline bool intersectsClip(const SkIRect& clip) const {
-        SkASSERT(SkFixedFloorToInt(fUpperY) < clip.fBottom);
-        return SkFixedCeilToInt(fLowerY) > clip.fTop;
-    }
-
-#ifdef SK_DEBUG
-    void dump() const {
-        SkDebugf("edge: upperY:%d lowerY:%d y:%g x:%g dx:%g w:%d\n",
-                 fUpperY, fLowerY, SkFixedToFloat(fY), SkFixedToFloat(fX),
-                 SkFixedToFloat(fDX), fWinding);
-    }
-
-    void validate() const {
-         SkASSERT(fPrev && fNext);
-         SkASSERT(fPrev->fNext == this);
-         SkASSERT(fNext->fPrev == this);
-
-         SkASSERT(fUpperY < fLowerY);
-         SkASSERT(SkAbs32(fWinding) == 1);
-    }
-#endif
-};
-
-struct SkAnalyticQuadraticEdge : public SkAnalyticEdge {
-    SkQuadraticEdge fQEdge;
-
-    // snap y to integer points in the middle of the curve to accelerate AAA path filling
-    SkFixed fSnappedX, fSnappedY;
-
-    bool setQuadratic(const SkPoint pts[3]);
-    bool updateQuadratic();
-};
-
-struct SkAnalyticCubicEdge : public SkAnalyticEdge {
-    SkCubicEdge fCEdge;
-
-    bool setCubic(const SkPoint pts[4]);
-    bool updateCubic();
-};
-
-bool SkAnalyticEdge::setLine(const SkPoint& p0, const SkPoint& p1, const SkIRect* clip) {
-    // We must set X/Y using the same way (times 4, to FDot6, then to Fixed) as Quads/Cubics.
-    // Otherwise the order of the edge might be wrong due to precision limit.
-    SkFixed x0 = SkFDot6ToFixed(SkScalarToFDot6(p0.fX * 4)) >> 2;
-    SkFixed y0 = snapY(SkFDot6ToFixed(SkScalarToFDot6(p0.fY * 4)) >> 2);
-    SkFixed x1 = SkFDot6ToFixed(SkScalarToFDot6(p1.fX * 4)) >> 2;
-    SkFixed y1 = snapY(SkFDot6ToFixed(SkScalarToFDot6(p1.fY * 4)) >> 2);
-
-    // are we a zero-height line?
-    if (y0 == y1) {
-        return false;
-    }
-
-    int top = SkFixedFloorToInt(y0);
-    int bot = SkFixedCeilToInt(y1);
-
-    // are we completely above or below the clip?
-    if (clip && (top >= clip->fBottom || bot <= clip->fTop)) {
-        return false;
-    }
-
-    int winding = 1;
-
-    if (y0 > y1) {
-        SkTSwap(x0, x1);
-        SkTSwap(y0, y1);
-        winding = -1;
-    }
-
-    SkFixed slope = SkFixedDiv(x1 - x0, y1 - y0);
-
-    fX          = x0;
-    fDX         = slope;
-    fUpperX     = x0;
-    fY          = y0;
-    fUpperY     = y0;
-    fLowerY     = y1;
-    fDY         = x1 != x0 ? SkAbs32(SkFixedDiv(y1 - y0, x1 - x0)) : SK_MaxS32;
-    fCurveCount = 0;
-    fWinding    = SkToS8(winding);
-    fCurveShift = 0;
-
-    if (clip) {
-        this->chopLineWithClip(*clip);
-    }
-    return true;
-}
-
-#endif