commit 4ccdaf6f2d6ed1da56a4012b89b24244a676bf9f
author Tyler Denniston <tdenniston@google.com> Wed Jul 22 14:04:59 2020 -0400
committer Skia Commit-Bot <skia-commit-bot@chromium.org> Wed Jul 22 18:49:20 2020 +0000
tree 88dc01ba0ae37141d46625b522de09b3a929a82b
parent baa2a7bdd2bcf49ce3290f8418b781372b2f281b

Show mirror drawn with SkStroke (toy stroker)

Improves the sample slide to draw the skeleton geometry, and a mirror
image of the current path with Skia's stroker, which makes it easier to
compare.

Change-Id: I804f4304aec6025112c8ccac3bb61139559022f5
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/305184
Reviewed-by: Tyler Denniston <tdenniston@google.com>
Commit-Queue: Tyler Denniston <tdenniston@google.com>

samplecode/SampleSimpleStroker.cpp

diff --git a/samplecode/SampleSimpleStroker.cpp b/samplecode/SampleSimpleStroker.cpp
index 28c3b24..c5c476e 100644
--- a/samplecode/SampleSimpleStroker.cpp
+++ b/samplecode/SampleSimpleStroker.cpp
@@ -348,15 +348,16 @@
 //////////////////////////////////////////////////////////////////////////////
 
 class SimpleStroker : public Sample {
-    bool fShowSkiaStroke, fShowHidden;
+    bool fShowSkiaStroke, fShowHidden, fShowSkeleton;
     float fWidth = 175;
-    SkPaint fPtsPaint, fStrokePaint, fNewFillPaint, fHiddenPaint;
+    SkPaint fPtsPaint, fStrokePaint, fMirrorStrokePaint, fNewFillPaint, fHiddenPaint,
+            fSkeletonPaint;
     static constexpr int kN = 3;
 
 public:
     SkPoint fPts[kN];
 
-    SimpleStroker() : fShowSkiaStroke(true), fShowHidden(false) {
+    SimpleStroker() : fShowSkiaStroke(true), fShowHidden(true), fShowSkeleton(true) {
         fPts[0] = {500, 200};
         fPts[1] = {300, 200};
         fPts[2] = {100, 100};
@@ -369,12 +370,20 @@
         fStrokePaint.setStyle(SkPaint::kStroke_Style);
         fStrokePaint.setColor(0x80FF0000);
 
+        fMirrorStrokePaint.setAntiAlias(true);
+        fMirrorStrokePaint.setStyle(SkPaint::kStroke_Style);
+        fMirrorStrokePaint.setColor(0x80FFFF00);
+
         fNewFillPaint.setAntiAlias(true);
         fNewFillPaint.setColor(0x8000FF00);
 
         fHiddenPaint.setAntiAlias(true);
         fHiddenPaint.setStyle(SkPaint::kStroke_Style);
         fHiddenPaint.setColor(0xFF0000FF);
+
+        fSkeletonPaint.setAntiAlias(true);
+        fSkeletonPaint.setStyle(SkPaint::kStroke_Style);
+        fSkeletonPaint.setColor(SK_ColorRED);
     }
 
     void toggle(bool& value) { value = !value; }
@@ -385,9 +394,12 @@
     bool onChar(SkUnichar uni) override {
         switch (uni) {
             case '1':
-                this->toggle(fShowSkiaStroke);
+                this->toggle(fShowSkeleton);
                 return true;
             case '2':
+                this->toggle(fShowSkiaStroke);
+                return true;
+            case '3':
                 this->toggle(fShowHidden);
                 return true;
             case '-':
@@ -430,8 +442,23 @@
         if (fShowHidden) {
             canvas->drawPath(fillPath, fHiddenPaint);
         }
-
+        if (fShowSkeleton) {
+            canvas->drawPath(path, fSkeletonPaint);
+        }
         canvas->drawPoints(SkCanvas::kPoints_PointMode, kN, fPts, fPtsPaint);
+
+        // Draw a mirror but using Skia's stroker.
+        canvas->translate(0, 400);
+        fMirrorStrokePaint.setStrokeWidth(fWidth);
+        canvas->drawPath(path, fMirrorStrokePaint);
+        if (fShowHidden) {
+            SkPath hidden;
+            fStrokePaint.getFillPath(path, &hidden);
+            canvas->drawPath(hidden, fHiddenPaint);
+        }
+        if (fShowSkeleton) {
+            canvas->drawPath(path, fSkeletonPaint);
+        }
     }
 
     Sample::Click* onFindClickHandler(SkScalar x, SkScalar y, skui::ModifierKey modi) override {