Change patheffect to take a (new) StrokeRec object, which encapsulates the fill

or stroke parameters for a path.

Today, the patheffect only sees if the caller was going to stroke or fill, and
if stroke, it just sees the width. With this change, the effect can see all of the
related parameters (e.g. cap/join/miter). No other change is intended at this
time.

After this change, I hope to use this additional data to allow SkDashPathEffect
to, at times, apply the stroke as part of its effect, which may be much more
efficient than first dashing, and then reading that and stroking it.

Most of these files changed just because of the new parameter to filterPath. The
key changes are in SkPathEffect.[h,cpp], SkPaint.cpp and SkScalerContext.cpp
Review URL: https://codereview.appspot.com/6250051

git-svn-id: http://skia.googlecode.com/svn/trunk@4048 2bbb7eff-a529-9590-31e7-b0007b416f81

1 files changed, 82 insertions, 98 deletions

diff --git a/src/core/SkPathEffect.cpp b/src/core/SkPathEffect.cpp
index dcce6d6b56..48d165a52e 100644
--- a/src/core/SkPathEffect.cpp
+++ b/src/core/SkPathEffect.cpp
@@ -10,6 +10,83 @@
 #include "SkPathEffect.h"
 #include "SkPath.h"
 #include "SkBuffer.h"
+#include "SkPaintDefaults.h"
+
+// must be < 0, since ==0 means hairline, and >0 means normal stroke
+#define kStrokeRec_FillStyleWidth     (-SK_Scalar1)
+
+SkStrokeRec::SkStrokeRec(InitStyle s) {
+    fWidth          = (kFill_InitStyle == s) ? kStrokeRec_FillStyleWidth : 0;
+    fMiterLimit     = SkPaintDefaults_MiterLimit;
+    fCap            = SkPaint::kDefault_Cap;
+    fJoin           = SkPaint::kDefault_Join;
+    fStrokeAndFill  = false;
+}
+
+SkStrokeRec::SkStrokeRec(const SkStrokeRec& src) {
+    memcpy(this, &src, sizeof(src));
+}
+
+SkStrokeRec::SkStrokeRec(const SkPaint& paint) {
+    switch (paint.getStyle()) {
+        case SkPaint::kFill_Style:
+            fWidth = kStrokeRec_FillStyleWidth;
+            fStrokeAndFill = false;
+            break;
+        case SkPaint::kStroke_Style:
+            fWidth = paint.getStrokeWidth();
+            fStrokeAndFill = false;
+            break;
+        case SkPaint::kStrokeAndFill_Style:
+            fWidth = paint.getStrokeWidth();
+            fStrokeAndFill = true;
+            break;
+        default:
+            SkASSERT(!"unknown paint style");
+            // fall back on just fill
+            fWidth = kStrokeRec_FillStyleWidth;
+            fStrokeAndFill = false;
+            break;
+    }
+
+    // copy these from the paint, regardless of our "style"
+    fMiterLimit = paint.getStrokeMiter();
+    fCap        = paint.getStrokeCap();
+    fJoin       = paint.getStrokeJoin();
+}
+
+SkStrokeRec::Style SkStrokeRec::getStyle() const {
+    if (fWidth < 0) {
+        return kFill_Style;
+    } else if (0 == fWidth) {
+        return kHairline_Style;
+    } else {
+        return fStrokeAndFill ? kStrokeAndFill_Style : kStroke_Style;
+    }
+}
+
+void SkStrokeRec::setFillStyle() {
+    fWidth = kStrokeRec_FillStyleWidth;
+}
+
+#include "SkStroke.h"
+
+bool SkStrokeRec::applyToPath(SkPath* dst, const SkPath& src) const {
+    if (fWidth <= 0) {  // hairline or fill
+        return false;
+    }
+
+    SkStroke stroker;
+    stroker.setCap(fCap);
+    stroker.setJoin(fJoin);
+    stroker.setMiterLimit(fMiterLimit);
+    stroker.setWidth(fWidth);
+    stroker.setDoFill(fStrokeAndFill);
+    stroker.strokePath(src, dst);
+    return true;
+}
+
+///////////////////////////////////////////////////////////////////////////////
 
 void SkPathEffect::computeFastBounds(SkRect* dst, const SkRect& src) {
     *dst = src;
@@ -48,7 +125,7 @@ SkPairPathEffect::SkPairPathEffect(SkFlattenableReadBuffer& buffer) {
 ///////////////////////////////////////////////////////////////////////////////
 
 bool SkComposePathEffect::filterPath(SkPath* dst, const SkPath& src,
-                                     SkScalar* width) {
+                                     SkStrokeRec* rec) {
     // we may have failed to unflatten these, so we have to check
     if (!fPE0 || !fPE1) {
         return false;
@@ -57,115 +134,22 @@ bool SkComposePathEffect::filterPath(SkPath* dst, const SkPath& src,
     SkPath          tmp;
     const SkPath*   ptr = &src;
 
-    if (fPE1->filterPath(&tmp, src, width)) {
+    if (fPE1->filterPath(&tmp, src, rec)) {
         ptr = &tmp;
     }
-    return fPE0->filterPath(dst, *ptr, width);
+    return fPE0->filterPath(dst, *ptr, rec);
 }
 
 ///////////////////////////////////////////////////////////////////////////////
 
 bool SkSumPathEffect::filterPath(SkPath* dst, const SkPath& src,
-                                 SkScalar* width) {
+                                 SkStrokeRec* rec) {
     // use bit-or so that we always call both, even if the first one succeeds
-    return  fPE0->filterPath(dst, src, width) | fPE1->filterPath(dst, src, width);
-}
-
-///////////////////////////////////////////////////////////////////////////////
-
-#include "SkStroke.h"
-
-/** \class SkStrokePathEffect
- 
- SkStrokePathEffect simulates stroking inside a patheffect, allowing the
- caller to have explicit control of when to stroke a path. Typically this is
- used if the caller wants to stroke before another patheffect is applied
- (using SkComposePathEffect or SkSumPathEffect).
- */
-class SkStrokePathEffect : public SkPathEffect {
-public:
-    SkStrokePathEffect(const SkPaint&);
-    SkStrokePathEffect(SkScalar width, SkPaint::Style, SkPaint::Join,
-                       SkPaint::Cap, SkScalar miterLimit = -1);
-    
-    // overrides
-    virtual bool filterPath(SkPath* dst, const SkPath& src, SkScalar* width);
-    
-    SK_DECLARE_PUBLIC_FLATTENABLE_DESERIALIZATION_PROCS(SkStrokePathEffect)
-    
-protected:
-    SkStrokePathEffect(SkFlattenableReadBuffer&);
-    virtual void flatten(SkFlattenableWriteBuffer&) const SK_OVERRIDE;
-    
-private:
-    SkScalar    fWidth, fMiter;
-    uint8_t     fStyle, fJoin, fCap;
-    
-    typedef SkPathEffect INHERITED;
-    
-    // illegal
-    SkStrokePathEffect(const SkStrokePathEffect&);
-    SkStrokePathEffect& operator=(const SkStrokePathEffect&);
-};
-
-SkStrokePathEffect::SkStrokePathEffect(const SkPaint& paint)
-    : fWidth(paint.getStrokeWidth()), fMiter(paint.getStrokeMiter()),
-      fStyle(SkToU8(paint.getStyle())), fJoin(SkToU8(paint.getStrokeJoin())),
-      fCap(SkToU8(paint.getStrokeCap())) {
-}
-
-SkStrokePathEffect::SkStrokePathEffect(SkScalar width, SkPaint::Style style,
-                           SkPaint::Join join, SkPaint::Cap cap, SkScalar miter)
-        : fWidth(width), fMiter(miter), fStyle(SkToU8(style)),
-          fJoin(SkToU8(join)), fCap(SkToU8(cap)) {
-    if (miter < 0) {  // signal they want the default
-        fMiter = SkIntToScalar(4);
-    }
-}
-
-bool SkStrokePathEffect::filterPath(SkPath* dst, const SkPath& src,
-                                    SkScalar* width) {
-    if (fWidth < 0 || fStyle == SkPaint::kFill_Style) {
-        return false;
-    }
-
-    if (fStyle == SkPaint::kStroke_Style && fWidth == 0) {  // hairline
-        *width = 0;
-        return true;
-    }
-
-    SkStroke    stroke;
-
-    stroke.setWidth(fWidth);
-    stroke.setMiterLimit(fMiter);
-    stroke.setJoin((SkPaint::Join)fJoin);
-    stroke.setCap((SkPaint::Cap)fCap);
-    stroke.setDoFill(fStyle == SkPaint::kStrokeAndFill_Style);
-
-    stroke.strokePath(src, dst);
-    return true;
-}
-
-void SkStrokePathEffect::flatten(SkFlattenableWriteBuffer& buffer) const {
-    this->INHERITED::flatten(buffer);
-    buffer.writeScalar(fWidth);
-    buffer.writeScalar(fMiter);
-    buffer.write8(fStyle);
-    buffer.write8(fJoin);
-    buffer.write8(fCap);
-}
-
-SkStrokePathEffect::SkStrokePathEffect(SkFlattenableReadBuffer& buffer) {
-    fWidth = buffer.readScalar();
-    fMiter = buffer.readScalar();
-    fStyle = buffer.readU8();
-    fJoin = buffer.readU8();
-    fCap = buffer.readU8();
+    return fPE0->filterPath(dst, src, rec) | fPE1->filterPath(dst, src, rec);
 }
 
 ///////////////////////////////////////////////////////////////////////////////
 
 SK_DEFINE_FLATTENABLE_REGISTRAR(SkComposePathEffect)
-//SK_DEFINE_FLATTENABLE_REGISTRAR(SkStrokePathEffect)
 SK_DEFINE_FLATTENABLE_REGISTRAR(SkSumPathEffect)