show flatness vectors in sample
Bug: skia:
Change-Id: I5a3882c993138dc5e1da92a7a4b1a9f96c740d1c
Reviewed-on: https://skia-review.googlesource.com/121461
Reviewed-by: Mike Reed <reed@google.com>
Commit-Queue: Mike Reed <reed@google.com>
diff --git a/samplecode/SamplePath.cpp b/samplecode/SamplePath.cpp
index 11b4167..f523fe6 100644
--- a/samplecode/SamplePath.cpp
+++ b/samplecode/SamplePath.cpp
@@ -590,6 +590,7 @@
SkPoint* fQuad = fPts + 4;
SkScalar fT = 0.5f;
bool fShowSub = false;
+ bool fShowFlatness = false;
CubicCurve2() {
fPts[0] = { 90, 300 };
@@ -612,6 +613,7 @@
if (SampleCode::CharQ(*evt, &uni)) {
switch (uni) {
case 's': fShowSub = !fShowSub; break;
+ case 'f': fShowFlatness = !fShowFlatness; break;
case '-': fT -= 1.0f / 32; break;
case '=': fT += 1.0f / 32; break;
default: goto DONE;
@@ -645,6 +647,29 @@
canvas->drawCircle(storage[i].fX, storage[i].fY, 4, paint);
}
}
+
+ void showFlattness(SkCanvas* canvas) {
+ SkPaint paint;
+ paint.setStyle(SkPaint::kStroke_Style);
+ paint.setAntiAlias(true);
+
+ paint.setColor(0xFF888888);
+ canvas->drawLine(fPts[0], fPts[3], paint);
+ canvas->drawLine(fQuad[0], fQuad[2], paint);
+
+ paint.setColor(0xFF0000FF);
+ SkPoint pts[2];
+ pts[0] = (fQuad[0] + fQuad[1] + fQuad[1] + fQuad[2])*0.25;
+ pts[1] = (fQuad[0] + fQuad[2]) * 0.5;
+ canvas->drawLine(pts[0], pts[1], paint);
+
+ SkVector v = fPts[0] - fPts[1] - fPts[1] + fPts[2];
+ v = v * 0.75;
+ canvas->drawLine(fPts[1], fPts[1] + v, paint);
+ v = fPts[1] - fPts[2] - fPts[2] + fPts[3];
+ v = v * 0.75;
+ canvas->drawLine(fPts[2], fPts[2] + v, paint);
+ }
void onDrawContent(SkCanvas* canvas) override {
SkPaint paint;
@@ -674,6 +699,10 @@
canvas->drawText(str.c_str(), str.size(), 20, 20, paint);
}
+ if (fShowFlatness) {
+ this->showFlattness(canvas);
+ }
+
paint.setStyle(SkPaint::kFill_Style);
paint.setColor(SK_ColorRED);
for (SkPoint p : fPts) {
