Add "enabled" flag to affectors, fix curve interaction with stable random
Flag is helpful while editing things (and could be a useful property to
animate, as well). The curve change fixes a bug where the stable generator
gets out of phase if all segments of a curve don't use the same options.
Bug: skia:
Change-Id: Ie151e775aee22957e79fa88feaafad72b6c781ff
Reviewed-on: https://skia-review.googlesource.com/c/195120
Reviewed-by: Brian Osman <brianosman@google.com>
Commit-Queue: Brian Osman <brianosman@google.com>
diff --git a/modules/particles/src/SkCurve.cpp b/modules/particles/src/SkCurve.cpp
index aa03853..1f14a79 100644
--- a/modules/particles/src/SkCurve.cpp
+++ b/modules/particles/src/SkCurve.cpp
@@ -24,12 +24,12 @@
return pts[0]*(ix*ix*ix) + pts[1]*(3*ix*ix*x) + pts[2]*(3*ix*x*x) + pts[3]*(x*x*x);
}
-SkScalar SkCurveSegment::eval(SkScalar x, SkRandom& random) const {
+SkScalar SkCurveSegment::eval(SkScalar x, SkScalar t, bool negate) const {
SkScalar result = fConstant ? fMin[0] : eval_cubic(fMin, x);
if (fRanged) {
- result += ((fConstant ? fMax[0] : eval_cubic(fMax, x)) - result) * random.nextF();
+ result += ((fConstant ? fMax[0] : eval_cubic(fMax, x)) - result) * t;
}
- if (fBidirectional && random.nextBool()) {
+ if (fBidirectional && negate) {
result = -result;
}
return result;
@@ -66,7 +66,12 @@
segmentX = rangeMin;
}
SkASSERT(0.0f <= segmentX && segmentX <= 1.0f);
- return fSegments[i].eval(segmentX, random);
+
+ // Always pull t and negate here, so that the stable generator behaves consistently, even if
+ // our segments use an inconsistent feature-set.
+ SkScalar t = random.nextF();
+ bool negate = random.nextBool();
+ return fSegments[i].eval(segmentX, t, negate);
}
void SkCurve::visitFields(SkFieldVisitor* v) {