Remove scaleToFit from DashPathEffect

src/effects/SkDashPathEffect.cpp

 
 /*
  * 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.
  */
 
 
 #include "SkDashPathEffect.h"
@@ skipping 17 matching lines @@
     }
     // If we get here, phase "appears" to be larger than our length. This
     // shouldn't happen with perfect precision, but we can accumulate errors
     // during the initial length computation (rounding can make our sum be too
     // big or too small. In that event, we just have to eat the error here.
     *index = 0;
     return intervals[0];
 }
 
 SkDashPathEffect::SkDashPathEffect(const SkScalar intervals[], int count,
-                                   SkScalar phase, bool scaleToFit)
-        : fScaleToFit(scaleToFit) {
+                                   SkScalar phase) {
     SkASSERT(intervals);
     SkASSERT(count > 1 && SkAlign2(count) == count);
 
     fIntervals = (SkScalar*)sk_malloc_throw(sizeof(SkScalar) * count);
     fCount = count;
 
     SkScalar len = 0;
     for (int i = 0; i < count; i++) {
         SkASSERT(intervals[i] >= 0);
         fIntervals[i] = intervals[i];
@@ skipping 199 matching lines @@
     SpecialLineRec lineRec;
     bool specialLine = lineRec.init(*srcPtr, dst, rec, fCount >> 1, fIntervalLength);
 
     SkPathMeasure   meas(*srcPtr, false);
 
     do {
         bool        skipFirstSegment = meas.isClosed();
         bool        addedSegment = false;
         SkScalar    length = meas.getLength();
         int         index = fInitialDashIndex;
-        SkScalar    scale = SK_Scalar1;
 
         // Since the path length / dash length ratio may be arbitrarily large, we can exert
         // significant memory pressure while attempting to build the filtered path. To avoid this,
         // we simply give up dashing beyond a certain threshold.
         //
         // The original bug report (http://crbug.com/165432) is based on a path yielding more than
         // 90 million dash segments and crashing the memory allocator. A limit of 1 million
         // segments seems reasonable: at 2 verbs per segment * 9 bytes per verb, this caps the
         // maximum dash memory overhead at roughly 17MB per path.
         static const SkScalar kMaxDashCount = 1000000;
         dashCount += length * (fCount >> 1) / fIntervalLength;
         if (dashCount > kMaxDashCount) {
             dst->reset();
             return false;
         }
 
-        if (fScaleToFit) {
-            if (fIntervalLength >= length) {
-                scale = SkScalarDiv(length, fIntervalLength);
-            } else {
-                SkScalar div = SkScalarDiv(length, fIntervalLength);
-                int n = SkScalarFloorToInt(div);
-                scale = SkScalarDiv(length, n * fIntervalLength);
-            }
-        }
-
         // Using double precision to avoid looping indefinitely due to single precision rounding
         // (for extreme path_length/dash_length ratios). See test_infinite_dash() unittest.
         double  distance = 0;
-        double  dlen = SkScalarMul(fInitialDashLength, scale);
+        double  dlen = fInitialDashLength;
 
         while (distance < length) {
             SkASSERT(dlen >= 0);
             addedSegment = false;
             if (is_even(index) && dlen > 0 && !skipFirstSegment) {
                 addedSegment = true;
                 ++segCount;
 
                 if (specialLine) {
                     lineRec.addSegment(SkDoubleToScalar(distance),
@@ skipping 11 matching lines @@
             skipFirstSegment = false;
 
             // wrap around our intervals array if necessary
             index += 1;
             SkASSERT(index <= fCount);
             if (index == fCount) {
                 index = 0;
             }
 
             // fetch our next dlen
-            dlen = SkScalarMul(intervals[index], scale);
+            dlen = intervals[index];
         }
 
         // extend if we ended on a segment and we need to join up with the (skipped) initial segment
         if (meas.isClosed() && is_even(fInitialDashIndex) &&
                 fInitialDashLength > 0) {
-            meas.getSegment(0, SkScalarMul(fInitialDashLength, scale), dst, !addedSegment);
+            meas.getSegment(0, fInitialDashLength, dst, !addedSegment);
             ++segCount;
         }
     } while (meas.nextContour());
 
     if (segCount > 1) {
         dst->setConvexity(SkPath::kConcave_Convexity);
     }
 
     return true;
 }
@@ skipping 17 matching lines @@
     // Additionally, they do not necessarily need to be integers.
     // We cannot allow arbitrary intervals since we want the returned points
     // to be uniformly sized.
     if (fCount != 2 ||
         !SkScalarNearlyEqual(fIntervals[0], fIntervals[1]) ||
         !SkScalarIsInt(fIntervals[0]) ||
         !SkScalarIsInt(fIntervals[1])) {
         return false;
     }
 
-    // TODO: this next test could be eased up. The rescaling should not impact
-    // the equality of the ons & offs. However, we would need to remove the
-    // integer intervals restriction first
-    if (fScaleToFit) {
-        return false;
-    }
-
     SkPoint pts[2];
 
     if (!src.isLine(pts)) {
         return false;
     }
 
     // TODO: this test could be eased up to allow circles
     if (SkPaint::kButt_Cap != rec.getCap()) {
         return false;
     }
@@ skipping 149 matching lines @@
 
 SkFlattenable::Factory SkDashPathEffect::getFactory() const {
     return CreateProc;
 }
 
 void SkDashPathEffect::flatten(SkWriteBuffer& buffer) const {
     this->INHERITED::flatten(buffer);
     buffer.writeInt(fInitialDashIndex);
     buffer.writeScalar(fInitialDashLength);
     buffer.writeScalar(fIntervalLength);
-    buffer.writeBool(fScaleToFit);
+    // Dummy write to stay compatible with old skps. Write will be removed in follow up patch.
+    buffer.writeBool(false);
     buffer.writeScalarArray(fIntervals, fCount);
 }
 
 SkFlattenable* SkDashPathEffect::CreateProc(SkReadBuffer& buffer) {
     return SkNEW_ARGS(SkDashPathEffect, (buffer));
 }
 
 SkDashPathEffect::SkDashPathEffect(SkReadBuffer& buffer) : INHERITED(buffer) {
     fInitialDashIndex = buffer.readInt();
     fInitialDashLength = buffer.readScalar();
     fIntervalLength = buffer.readScalar();
-    fScaleToFit = buffer.readBool();
+    buffer.readBool(); // dummy read to stay compatible with old skps
 
     fCount = buffer.getArrayCount();
     size_t allocSize = sizeof(SkScalar) * fCount;
     if (buffer.validateAvailable(allocSize)) {
         fIntervals = (SkScalar*)sk_malloc_throw(allocSize);
         buffer.readScalarArray(fIntervals, fCount);
     } else {
         fIntervals = NULL;
     }
 }