skia2/tests/Float16Test.cpp
mtklein cbefc5e4ca Revert of SkHalfToFloat_01 / SkFloatToHalf_01 (patchset #11 id:200001 of https://codereview.chromium.org/1685133005/ )
Reason for revert:
Gotta fix Test-Ubuntu-GCC-GCE-CPU-AVX2-x86_64-Release-SKNX_NO_SIMD

Original issue's description:
> SkHalfToFloat_01 / SkFloatToHalf_01
>
> These are basically inlined, 4-at-a-time versions of our existing functions,
> but cut down to avoid any work that's only necessary outside [0,1].
>
> Both f16 and f32 denorms should work fine modulo the usual ARMv7 NEON denorm==zero caveat.
>
> In exchange for a little speed, f32->f16 does not round properly.
> Instead it truncates, so it's never off by more than 1 bit.
>
> Support for finite values >1 or <0 is straightforward to add back.
> >1 might already work as-is.
>
> Getting close to _u16 performance:
>     micros   	bench
>     261.13  	xferu64_bw_1_opaque_u16
>    1833.51  	xferu64_bw_1_alpha_u16
>    2762.32 ?	xferu64_aa_1_opaque_u16
>    3334.29  	xferu64_aa_1_alpha_u16
>     249.78  	xferu64_bw_1_opaque_f16
>    3383.18  	xferu64_bw_1_alpha_f16
>    4214.72  	xferu64_aa_1_opaque_f16
>    4701.19  	xferu64_aa_1_alpha_f16
>
>
> BUG=skia:
> GOLD_TRYBOT_URL= https://gold.skia.org/search2?unt=true&query=source_type%3Dgm&master=false&issue=1685133005
>
> Committed: https://skia.googlesource.com/skia/+/9ea11a4235b3e3521cc8bf914a27c2d0dc062db9

TBR=jvanverth@google.com,reed@google.com,mtklein@chromium.org
# Skipping CQ checks because original CL landed less than 1 days ago.
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=skia:

Review URL: https://codereview.chromium.org/1693443003
2016-02-11 06:00:49 -08:00

67 lines
1.9 KiB
C++

/*
* Copyright 2016 Google Inc.
*
* Use of this source code is governed by a BSD-style license that can be
* found in the LICENSE file.
*/
#include "Test.h"
#include "SkColor.h"
#include "SkHalf.h"
#include "SkOpts.h"
#include "SkPixmap.h"
static bool eq_within_half_float(float a, float b) {
const float kTolerance = 1.0f / (1 << (8 + 10));
SkHalf ha = SkFloatToHalf(a);
SkHalf hb = SkFloatToHalf(b);
float a2 = SkHalfToFloat(ha);
float b2 = SkHalfToFloat(hb);
return fabsf(a2 - b2) <= kTolerance;
}
static bool eq_within_half_float(const SkPM4f& a, const SkPM4f& b) {
for (int i = 0; i < 4; ++i) {
if (!eq_within_half_float(a.fVec[i], b.fVec[i])) {
return false;
}
}
return true;
}
DEF_TEST(color_half_float, reporter) {
const int w = 100;
const int h = 100;
SkImageInfo info = SkImageInfo::Make(w, h, kRGBA_F16_SkColorType, kPremul_SkAlphaType);
SkAutoPixmapStorage pm;
pm.alloc(info);
REPORTER_ASSERT(reporter, pm.getSafeSize() == SkToSizeT(w * h * sizeof(uint64_t)));
SkColor4f c4 { 0.5f, 1, 0.5f, 0.25f };
pm.erase(c4);
SkPM4f origpm4 = c4.premul();
for (int y = 0; y < pm.height(); ++y) {
for (int x = 0; x < pm.width(); ++x) {
SkPM4f pm4 = SkPM4f::FromF16(pm.addrF16(x, y));
REPORTER_ASSERT(reporter, eq_within_half_float(origpm4, pm4));
}
}
}
DEF_TEST(float_to_half, reporter) {
const float fs[] = { 1.0, 2.0, 3.0, 4.0, 5.0, 6.0, 7.0 };
const uint16_t hs[] = { 0x3c00, 0x4000, 0x4200, 0x4400, 0x4500, 0x4600, 0x4700 };
uint16_t hscratch[7];
SkOpts::float_to_half(hscratch, fs, 7);
REPORTER_ASSERT(reporter, 0 == memcmp(hscratch, hs, sizeof(hs)));
float fscratch[7];
SkOpts::half_to_float(fscratch, hs, 7);
REPORTER_ASSERT(reporter, 0 == memcmp(fscratch, fs, sizeof(fs)));
}