Reland of Add fast normalize for SkLightingImageFilter. (patchset #1 id:1 of https://codereview.chromium.org/1244523002/)

Reason for revert:
Florin will rebaseline the images.

Original issue's description:
> Revert of Add fast normalize for SkLightingImageFilter. (patchset #2 id:20001 of https://codereview.chromium.org/1240023002/)
>
> Reason for revert:
> Speculative revert -- DEPS roll block on linux_blink_rel
>
> https://storage.googleapis.com/chromium-layout-test-archives/linux_blink_rel/71483/layout-test-results/results.html
>
> Original issue's description:
> > Add fast normalize for SkLightingImageFilter.
> >
> > The normalize routine in SkPoint3 is very robust. However, for simple
> > lighting cases we prefer speed over robustness. This fixes a perf
> > regression in smoothness.tough_filters_cases.
> >
> > BUG=chromium:510562
> >
> > Committed: https://skia.googlesource.com/skia/+/dfa0ecf169db87f7afddd93bc1c500de481a62c7
>
> TBR=reed@google.com,senorblanco@google.com,senorblanco@chromium.org,jvanverth@google.com
> NOPRESUBMIT=true
> NOTREECHECKS=true
> NOTRY=true
> BUG=chromium:510562
>
> Committed: https://skia.googlesource.com/skia/+/ac66a8122b27c388cc74b3913d9a9be351a44e54

TBR=reed@google.com,senorblanco@google.com,senorblanco@chromium.org,reed@chromium.org
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=chromium:510562

Review URL: https://codereview.chromium.org/1241583007
This commit is contained in:
jvanverth 2015-07-17 07:22:30 -07:00 committed by Commit bot
parent 84984efeb6
commit 992c761239

View File

@ -60,6 +60,15 @@ inline void shiftMatrixLeft(int m[9]) {
m[7] = m[8];
}
static inline void fast_normalize(SkPoint3* vector) {
// add a tiny bit so we don't have to worry about divide-by-zero
SkScalar magSq = vector->dot(*vector) + SK_ScalarNearlyZero;
SkScalar scale = sk_float_rsqrt(magSq);
vector->fX *= scale;
vector->fY *= scale;
vector->fZ *= scale;
}
class DiffuseLightingType {
public:
DiffuseLightingType(SkScalar kd)
@ -90,7 +99,7 @@ public:
const SkPoint3& lightColor) const {
SkPoint3 halfDir(surfaceTolight);
halfDir.fZ += SK_Scalar1; // eye position is always (0, 0, 1)
halfDir.normalize();
fast_normalize(&halfDir);
SkScalar colorScale = SkScalarMul(fKS,
SkScalarPow(normal.dot(halfDir), fShininess));
colorScale = SkScalarClampMax(colorScale, SK_Scalar1);
@ -113,7 +122,7 @@ inline SkPoint3 pointToNormal(SkScalar x, SkScalar y, SkScalar surfaceScale) {
SkPoint3 vector = SkPoint3::Make(SkScalarMul(-x, surfaceScale),
SkScalarMul(-y, surfaceScale),
SK_Scalar1);
vector.normalize();
fast_normalize(&vector);
return vector;
}
@ -800,7 +809,7 @@ public:
fLocation.fY - SkIntToScalar(y),
fLocation.fZ - SkScalarMul(SkIntToScalar(z),
surfaceScale));
direction.normalize();
fast_normalize(&direction);
return direction;
};
const SkPoint3& lightColor(const SkPoint3&) const { return this->color(); }
@ -866,7 +875,7 @@ public:
fSpecularExponent(SkScalarPin(specularExponent, kSpecularExponentMin, kSpecularExponentMax))
{
fS = target - location;
fS.normalize();
fast_normalize(&fS);
fCosOuterConeAngle = SkScalarCos(SkDegreesToRadians(cutoffAngle));
const SkScalar antiAliasThreshold = 0.016f;
fCosInnerConeAngle = fCosOuterConeAngle + antiAliasThreshold;
@ -888,7 +897,7 @@ public:
SkPoint3 target = SkPoint3::Make(target2.fX, target2.fY,
SkScalarAve(targetZ.fX, targetZ.fY));
SkPoint3 s = target - location;
s.normalize();
fast_normalize(&s);
return new SkSpotLight(location,
target,
fSpecularExponent,
@ -904,7 +913,7 @@ public:
fLocation.fY - SkIntToScalar(y),
fLocation.fZ - SkScalarMul(SkIntToScalar(z),
surfaceScale));
direction.normalize();
fast_normalize(&direction);
return direction;
};
SkPoint3 lightColor(const SkPoint3& surfaceToLight) const {