use pinned value during lerp for vertical gradients
slight formatting clean up on associated gm
BUG=skia:
Review URL: https://codereview.chromium.org/1471543002
diff --git a/gm/gradients.cpp b/gm/gradients.cpp
index 92e22ee..9c4d621 100644
--- a/gm/gradients.cpp
+++ b/gm/gradients.cpp
@@ -610,19 +610,20 @@
SkPoint pts[2];
SkScalar pos[kStopCount];
} configs[] = {
- { { SkPoint::Make(0, 0), SkPoint::Make(10, 0) }, { 0, 0.999999f, 1 }},
- { { SkPoint::Make(0, 0), SkPoint::Make(10, 0) }, { 0, 0.000001f, 1 }},
- { { SkPoint::Make(0, 0), SkPoint::Make(10, 0) }, { 0, 0.999999999f, 1 }},
- { { SkPoint::Make(0, 0), SkPoint::Make(10, 0) }, { 0, 0.000000001f, 1 }},
- { { SkPoint::Make(0, 0), SkPoint::Make(0, 10) }, { 0, 0.999999f, 1 }},
- { { SkPoint::Make(0, 0), SkPoint::Make(0, 10) }, { 0, 0.000001f, 1 }},
- { { SkPoint::Make(0, 0), SkPoint::Make(0, 10) }, { 0, 0.999999999f, 1 }},
- { { SkPoint::Make(0, 0), SkPoint::Make(0, 10) }, { 0, 0.000000001f, 1 }},
+ { { SkPoint::Make(0, 0), SkPoint::Make(10, 0) }, { 0, 0.999999f, 1 }},
+ { { SkPoint::Make(0, 0), SkPoint::Make(10, 0) }, { 0, 0.000001f, 1 }},
+ { { SkPoint::Make(0, 0), SkPoint::Make(10, 0) }, { 0, 0.999999999f, 1 }},
+ { { SkPoint::Make(0, 0), SkPoint::Make(10, 0) }, { 0, 0.000000001f, 1 }},
- { { SkPoint::Make(0, 0), SkPoint::Make(0.00001f, 0) } , { 0, 0.5f, 1 }},
- { { SkPoint::Make(9.99999f, 0), SkPoint::Make(10, 0) }, { 0, 0.5f, 1 }},
- { { SkPoint::Make(0, 0), SkPoint::Make(0, 0.00001f) }, { 0, 0.5f, 1 }},
- { { SkPoint::Make(0, 9.99999f), SkPoint::Make(0, 10) }, { 0, 0.5f, 1 }},
+ { { SkPoint::Make(0, 0), SkPoint::Make(0, 10) }, { 0, 0.999999f, 1 }},
+ { { SkPoint::Make(0, 0), SkPoint::Make(0, 10) }, { 0, 0.000001f, 1 }},
+ { { SkPoint::Make(0, 0), SkPoint::Make(0, 10) }, { 0, 0.999999999f, 1 }},
+ { { SkPoint::Make(0, 0), SkPoint::Make(0, 10) }, { 0, 0.000000001f, 1 }},
+
+ { { SkPoint::Make(0, 0), SkPoint::Make(0.00001f, 0) }, { 0, 0.5f, 1 }},
+ { { SkPoint::Make(9.99999f, 0), SkPoint::Make(10, 0) }, { 0, 0.5f, 1 }},
+ { { SkPoint::Make(0, 0), SkPoint::Make(0, 0.00001f) }, { 0, 0.5f, 1 }},
+ { { SkPoint::Make(0, 9.99999f), SkPoint::Make(0, 10) }, { 0, 0.5f, 1 }},
};
SkPaint paint;
diff --git a/src/effects/gradients/SkLinearGradient.cpp b/src/effects/gradients/SkLinearGradient.cpp
index 013c1f1..bfa473c 100644
--- a/src/effects/gradients/SkLinearGradient.cpp
+++ b/src/effects/gradients/SkLinearGradient.cpp
@@ -727,6 +727,9 @@
*/
static Sk4f lerp_color(float fx, const SkLinearGradient::LinearGradientContext::Rec* rec) {
+ SkASSERT(fx >= rec[0].fPos);
+ SkASSERT(fx <= rec[1].fPos);
+
const float p0 = rec[0].fPos;
const Sk4f c0 = rec[0].fColor;
const Sk4f c1 = rec[1].fColor;
@@ -894,7 +897,8 @@
const float invDx = 1 / dx;
if (SkScalarNearlyZero(dx)) { // gradient is vertical
- Sk4f c = lerp_color(fx, find_forward(fRecs.begin(), SkTPin(fx, 0.0f, 1.0f)));
+ const float pinFx = SkTPin(fx, 0.0f, 1.0f);
+ Sk4f c = lerp_color(pinFx, find_forward(fRecs.begin(), pinFx));
if (fApplyAlphaAfterInterp) {
fill<true>(dstC, count, c + dither0, c + dither1);
} else {