Revert of allow canvas to force conservative clips (for speed) (patchset #7 id:120001 of https://codereview.chromium.org/541593005/)

Reason for revert:
multipicturedraw failed on nvprmsaa -- don't know why yet

Original issue's description:
> Allow SkCanvas to be initialized to force conservative rasterclips. This has the following effects:
>
> 1. Queries to the current clip will be conservatively large. This can mean the quickReject may return false more often.
>
> 2. The conservative clips mean less work is done.
>
> 3. Enabled by default for Gpu, Record, and NoSaveLayer canvases.
>
> 4. API is private for now.
>
> Committed: https://skia.googlesource.com/skia/+/27a5e656c3d6ef22f9cb34de18e1b960da3aa241

R=robertphillips@google.com, bsalomon@google.com, mtklein@google.com, junov@google.com
TBR=bsalomon@google.com, junov@google.com, mtklein@google.com, robertphillips@google.com
NOTREECHECKS=true
NOTRY=true

Author: reed@google.com

Review URL: https://codereview.chromium.org/554033003

1 files changed, 14 insertions, 124 deletions

diff --git a/src/core/SkRasterClip.cpp b/src/core/SkRasterClip.cpp
index f820c5a0a4..dab91d8f4c 100644
--- a/src/core/SkRasterClip.cpp
+++ b/src/core/SkRasterClip.cpp
@@ -6,12 +6,18 @@
  */
 
 #include "SkRasterClip.h"
-#include "SkPath.h"
+
+
+SkRasterClip::SkRasterClip() {
+    fIsBW = true;
+    fIsEmpty = true;
+    fIsRect = false;
+    SkDEBUGCODE(this->validate();)
+}
 
 SkRasterClip::SkRasterClip(const SkRasterClip& src) {
     AUTO_RASTERCLIP_VALIDATE(src);
 
-    fForceConservativeRects = src.fForceConservativeRects;
     fIsBW = src.fIsBW;
     if (fIsBW) {
         fBW = src.fBW;
@@ -24,22 +30,13 @@ SkRasterClip::SkRasterClip(const SkRasterClip& src) {
     SkDEBUGCODE(this->validate();)
 }
 
-SkRasterClip::SkRasterClip(const SkIRect& bounds, bool forceConservativeRects) : fBW(bounds) {
-    fForceConservativeRects = forceConservativeRects;
+SkRasterClip::SkRasterClip(const SkIRect& bounds) : fBW(bounds) {
     fIsBW = true;
     fIsEmpty = this->computeIsEmpty();  // bounds might be empty, so compute
     fIsRect = !fIsEmpty;
     SkDEBUGCODE(this->validate();)
 }
 
-SkRasterClip::SkRasterClip(bool forceConservativeRects) {
-    fForceConservativeRects = forceConservativeRects;
-    fIsBW = true;
-    fIsEmpty = true;
-    fIsRect = false;
-    SkDEBUGCODE(this->validate();)
-}
-
 SkRasterClip::~SkRasterClip() {
     SkDEBUGCODE(this->validate();)
 }
@@ -73,84 +70,9 @@ bool SkRasterClip::setRect(const SkIRect& rect) {
     return fIsRect;
 }
 
-/////////////////////////////////////////////////////////////////////////////////////
-
-bool SkRasterClip::setConservativeRect(const SkRect& r, const SkIRect& clipR, bool isInverse) {
-    SkIRect ir;
-    r.roundOut(&ir);
-
-    SkRegion::Op op;
-    if (isInverse) {
-        op = SkRegion::kDifference_Op;
-    } else {
-        op = SkRegion::kIntersect_Op;
-    }
-    fBW.setRect(clipR);
-    fBW.op(ir, op);
-    return this->updateCacheAndReturnNonEmpty();
-}
-
-/////////////////////////////////////////////////////////////////////////////////////
-
-enum MutateResult {
-    kDoNothing_MutateResult,
-    kReplaceClippedAgainstGlobalBounds_MutateResult,
-    kContinue_MutateResult,
-};
-
-static MutateResult mutate_conservative_op(SkRegion::Op* op, bool inverseFilled) {
-    if (inverseFilled) {
-        switch (*op) {
-            case SkRegion::kIntersect_Op:
-            case SkRegion::kDifference_Op:
-                // These ops can only shrink the current clip. So leaving
-                // the clip unchanged conservatively respects the contract.
-                return kDoNothing_MutateResult;
-            case SkRegion::kUnion_Op:
-            case SkRegion::kReplace_Op:
-            case SkRegion::kReverseDifference_Op:
-            case SkRegion::kXOR_Op: {
-                // These ops can grow the current clip up to the extents of
-                // the input clip, which is inverse filled, so we just set
-                // the current clip to the device bounds.
-                *op = SkRegion::kReplace_Op;
-                return kReplaceClippedAgainstGlobalBounds_MutateResult;
-            }
-        }
-    } else {
-        // Not inverse filled
-        switch (*op) {
-            case SkRegion::kIntersect_Op:
-            case SkRegion::kUnion_Op:
-            case SkRegion::kReplace_Op:
-                return kContinue_MutateResult;
-            case SkRegion::kDifference_Op:
-                // Difference can only shrink the current clip.
-                // Leaving clip unchanged conservatively fullfills the contract.
-                return kDoNothing_MutateResult;
-            case SkRegion::kReverseDifference_Op:
-                // To reverse, we swap in the bounds with a replace op.
-                // As with difference, leave it unchanged.
-                *op = SkRegion::kReplace_Op;
-                return kContinue_MutateResult;
-            case SkRegion::kXOR_Op:
-                // Be conservative, based on (A XOR B) always included in (A union B),
-                // which is always included in (bounds(A) union bounds(B))
-                *op = SkRegion::kUnion_Op;
-                return kContinue_MutateResult;
-        }
-    }
-    SkFAIL("should not get here");
-    return kDoNothing_MutateResult;
-}
-
 bool SkRasterClip::setPath(const SkPath& path, const SkRegion& clip, bool doAA) {
     AUTO_RASTERCLIP_VALIDATE(*this);
 
-    if (fForceConservativeRects) {
-        return this->setConservativeRect(path.getBounds(), clip.getBounds(), path.isInverseFillType());
-    }
-
     if (this->isBW() && !doAA) {
         (void)fBW.setPath(path, clip);
     } else {
@@ -168,22 +90,7 @@ bool SkRasterClip::op(const SkPath& path, const SkISize& size, SkRegion::Op op,
     // base is used to limit the size (and therefore memory allocation) of the
     // region that results from scan converting devPath.
     SkRegion base;
-
-    if (fForceConservativeRects) {
-        SkIRect ir;
-        switch (mutate_conservative_op(&op, path.isInverseFillType())) {
-            case kDoNothing_MutateResult:
-                return !this->isEmpty();
-            case kReplaceClippedAgainstGlobalBounds_MutateResult:
-                ir = SkIRect::MakeSize(size);
-                break;
-            case kContinue_MutateResult:
-                path.getBounds().roundOut(&ir);
-                break;
-        }
-        return this->op(ir, op);
-    }
-
+    
     if (SkRegion::kIntersect_Op == op) {
         // since we are intersect, we can do better (tighter) with currRgn's
         // bounds, than just using the device. However, if currRgn is complex,
@@ -195,7 +102,7 @@ bool SkRasterClip::op(const SkPath& path, const SkISize& size, SkRegion::Op op,
             return this->setPath(path, this->bwRgn(), doAA);
         } else {
             base.setRect(this->getBounds());
-            SkRasterClip clip(fForceConservativeRects);
+            SkRasterClip clip;
             clip.setPath(path, base, doAA);
             return this->op(clip, op);
         }
@@ -205,7 +112,7 @@ bool SkRasterClip::op(const SkPath& path, const SkISize& size, SkRegion::Op op,
         if (SkRegion::kReplace_Op == op) {
             return this->setPath(path, base, doAA);
         } else {
-            SkRasterClip clip(fForceConservativeRects);
+            SkRasterClip clip;
             clip.setPath(path, base, doAA);
             return this->op(clip, op);
         }
@@ -275,24 +182,9 @@ static bool nearly_integral(SkScalar x) {
     return x - SkScalarFloorToScalar(x) < domain;
 }
 
-bool SkRasterClip::op(const SkRect& r, const SkISize& size, SkRegion::Op op, bool doAA) {
+bool SkRasterClip::op(const SkRect& r, SkRegion::Op op, bool doAA) {
     AUTO_RASTERCLIP_VALIDATE(*this);
 
-    if (fForceConservativeRects) {
-        SkIRect ir;
-        switch (mutate_conservative_op(&op, false)) {
-            case kDoNothing_MutateResult:
-                return !this->isEmpty();
-            case kReplaceClippedAgainstGlobalBounds_MutateResult:
-                ir = SkIRect::MakeSize(size);
-                break;
-            case kContinue_MutateResult:
-                r.roundOut(&ir);
-                break;
-        }
-        return this->op(ir, op);
-    }
-    
     if (fIsBW && doAA) {
         // check that the rect really needs aa, or is it close enought to
         // integer boundaries that we can just treat it as a BW rect?
@@ -359,9 +251,7 @@ const SkRegion& SkRasterClip::forceGetBW() {
 
 void SkRasterClip::convertToAA() {
     AUTO_RASTERCLIP_VALIDATE(*this);
-    
-    SkASSERT(!fForceConservativeRects);
-    
+
     SkASSERT(fIsBW);
     fAA.setRegion(fBW);
     fIsBW = false;