skia2/tests/M44Test.cpp
Michael Ludwig 68e4e20fae Add unit test to cover incorrect image filter layer bounds bug
Pulls the matrix and layer bounds from the captured skp that was
originally clipped, and asserts that both SkMatrix and SkM44's
separate mapRect functions don't regress.

Bug: skia:12335
Change-Id: I092d60b8a38fcd3cb70a8123802d730644cffda1
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/439276
Commit-Queue: Michael Ludwig <michaelludwig@google.com>
Commit-Queue: Florin Malita <fmalita@google.com>
Auto-Submit: Michael Ludwig <michaelludwig@google.com>
Reviewed-by: Florin Malita <fmalita@google.com>
2021-08-13 14:25:14 +00:00

375 lines
15 KiB
C++

/*
* Copyright 2020 Google Inc.
*
* Use of this source code is governed by a BSD-style license that can be
* found in the LICENSE file.
*/
#include "include/core/SkM44.h"
#include "include/utils/SkRandom.h"
#include "src/core/SkMatrixPriv.h"
#include "tests/Test.h"
static bool eq(const SkM44& a, const SkM44& b, float tol) {
float fa[16], fb[16];
a.getColMajor(fa);
b.getColMajor(fb);
for (int i = 0; i < 16; ++i) {
if (!SkScalarNearlyEqual(fa[i], fb[i], tol)) {
return false;
}
}
return true;
}
DEF_TEST(M44, reporter) {
SkM44 m, im;
REPORTER_ASSERT(reporter, SkM44(1, 0, 0, 0,
0, 1, 0, 0,
0, 0, 1, 0,
0, 0, 0, 1) == m);
REPORTER_ASSERT(reporter, SkM44() == m);
REPORTER_ASSERT(reporter, m.invert(&im));
REPORTER_ASSERT(reporter, SkM44() == im);
m.setTranslate(3, 4, 2);
REPORTER_ASSERT(reporter, SkM44(1, 0, 0, 3,
0, 1, 0, 4,
0, 0, 1, 2,
0, 0, 0, 1) == m);
const float f[] = { 1, 0, 0, 2, 3, 1, 2, 5, 0, 5, 3, 0, 0, 1, 0, 2 };
m = SkM44::ColMajor(f);
REPORTER_ASSERT(reporter, SkM44(f[0], f[4], f[ 8], f[12],
f[1], f[5], f[ 9], f[13],
f[2], f[6], f[10], f[14],
f[3], f[7], f[11], f[15]) == m);
{
SkM44 t = m.transpose();
REPORTER_ASSERT(reporter, t != m);
REPORTER_ASSERT(reporter, t.rc(1,0) == m.rc(0,1));
SkM44 tt = t.transpose();
REPORTER_ASSERT(reporter, tt == m);
}
m = SkM44::RowMajor(f);
REPORTER_ASSERT(reporter, SkM44(f[ 0], f[ 1], f[ 2], f[ 3],
f[ 4], f[ 5], f[ 6], f[ 7],
f[ 8], f[ 9], f[10], f[14],
f[12], f[13], f[14], f[15]) == m);
REPORTER_ASSERT(reporter, m.invert(&im));
m = m * im;
// m should be identity now, but our calc is not perfect...
REPORTER_ASSERT(reporter, eq(SkM44(), m, 0.0000005f));
REPORTER_ASSERT(reporter, SkM44() != m);
}
DEF_TEST(M44_v3, reporter) {
SkV3 a = {1, 2, 3},
b = {1, 2, 2};
REPORTER_ASSERT(reporter, a.lengthSquared() == 1 + 4 + 9);
REPORTER_ASSERT(reporter, b.length() == 3);
REPORTER_ASSERT(reporter, a.dot(b) == 1 + 4 + 6);
REPORTER_ASSERT(reporter, b.dot(a) == 1 + 4 + 6);
REPORTER_ASSERT(reporter, (a.cross(b) == SkV3{-2, 1, 0}));
REPORTER_ASSERT(reporter, (b.cross(a) == SkV3{ 2, -1, 0}));
SkM44 m = {
2, 0, 0, 3,
0, 1, 0, 5,
0, 0, 3, 1,
0, 0, 0, 1
};
SkV3 c = m * a;
REPORTER_ASSERT(reporter, (c == SkV3{2, 2, 9}));
SkV4 d = m.map(4, 3, 2, 1);
REPORTER_ASSERT(reporter, (d == SkV4{11, 8, 7, 1}));
}
DEF_TEST(M44_v4, reporter) {
SkM44 m( 1, 2, 3, 4,
5, 6, 7, 8,
9, 10, 11, 12,
13, 14, 15, 16);
SkV4 r0 = m.row(0),
r1 = m.row(1),
r2 = m.row(2),
r3 = m.row(3);
REPORTER_ASSERT(reporter, (r0 == SkV4{ 1, 2, 3, 4}));
REPORTER_ASSERT(reporter, (r1 == SkV4{ 5, 6, 7, 8}));
REPORTER_ASSERT(reporter, (r2 == SkV4{ 9, 10, 11, 12}));
REPORTER_ASSERT(reporter, (r3 == SkV4{13, 14, 15, 16}));
REPORTER_ASSERT(reporter, SkM44::Rows(r0, r1, r2, r3) == m);
SkV4 c0 = m.col(0),
c1 = m.col(1),
c2 = m.col(2),
c3 = m.col(3);
REPORTER_ASSERT(reporter, (c0 == SkV4{1, 5, 9, 13}));
REPORTER_ASSERT(reporter, (c1 == SkV4{2, 6, 10, 14}));
REPORTER_ASSERT(reporter, (c2 == SkV4{3, 7, 11, 15}));
REPORTER_ASSERT(reporter, (c3 == SkV4{4, 8, 12, 16}));
REPORTER_ASSERT(reporter, SkM44::Cols(c0, c1, c2, c3) == m);
// implement matrix * vector using column vectors
SkV4 v = {1, 2, 3, 4};
SkV4 v1 = m * v;
SkV4 v2 = c0 * v.x + c1 * v.y + c2 * v.z + c3 * v.w;
REPORTER_ASSERT(reporter, v1 == v2);
REPORTER_ASSERT(reporter, (c0 + r0 == SkV4{c0.x+r0.x, c0.y+r0.y, c0.z+r0.z, c0.w+r0.w}));
REPORTER_ASSERT(reporter, (c0 - r0 == SkV4{c0.x-r0.x, c0.y-r0.y, c0.z-r0.z, c0.w-r0.w}));
REPORTER_ASSERT(reporter, (c0 * r0 == SkV4{c0.x*r0.x, c0.y*r0.y, c0.z*r0.z, c0.w*r0.w}));
}
DEF_TEST(M44_rotate, reporter) {
const SkV3 x = {1, 0, 0},
y = {0, 1, 0},
z = {0, 0, 1};
// We have radians version of setRotateAbout methods, but even with our best approx
// for PI, sin(SK_ScalarPI) != 0, so to make the comparisons in the unittest clear,
// I'm using the variants that explicitly take the sin,cos values.
struct {
SkScalar sinAngle, cosAngle;
SkV3 aboutAxis;
SkV3 expectedX, expectedY, expectedZ;
} recs[] = {
{ 0, 1, x, x, y, z}, // angle = 0
{ 0, 1, y, x, y, z}, // angle = 0
{ 0, 1, z, x, y, z}, // angle = 0
{ 0,-1, x, x,-y,-z}, // angle = 180
{ 0,-1, y, -x, y,-z}, // angle = 180
{ 0,-1, z, -x,-y, z}, // angle = 180
// Skia coordinate system is right-handed
{ 1, 0, x, x, z,-y}, // angle = 90
{ 1, 0, y, -z, y, x}, // angle = 90
{ 1, 0, z, y,-x, z}, // angle = 90
{-1, 0, x, x,-z, y}, // angle = -90
{-1, 0, y, z, y,-x}, // angle = -90
{-1, 0, z, -y, x, z}, // angle = -90
};
for (const auto& r : recs) {
SkM44 m(SkM44::kNaN_Constructor);
m.setRotateUnitSinCos(r.aboutAxis, r.sinAngle, r.cosAngle);
auto mx = m * x;
auto my = m * y;
auto mz = m * z;
REPORTER_ASSERT(reporter, mx == r.expectedX);
REPORTER_ASSERT(reporter, my == r.expectedY);
REPORTER_ASSERT(reporter, mz == r.expectedZ);
// flipping the axis-of-rotation should flip the results
mx = m * -x;
my = m * -y;
mz = m * -z;
REPORTER_ASSERT(reporter, mx == -r.expectedX);
REPORTER_ASSERT(reporter, my == -r.expectedY);
REPORTER_ASSERT(reporter, mz == -r.expectedZ);
}
}
DEF_TEST(M44_rectToRect, reporter) {
SkV2 dstScales[] = {
{1.f, 1.f}, // no aspect ratio change, nor up/down scaling
{0.25f, 0.5f}, // aspect ratio narrows, downscale x and y
{0.5f, 0.25f}, // aspect ratio widens, downscale x and y
{0.5f, 0.5f}, // no aspect ratio change, downscale x and y
{2.f, 3.f}, // aspect ratio narrows, upscale x and y
{3.f, 2.f}, // aspect ratio widens, upscale x and y
{2.f, 2.f}, // no aspect ratio change, upscale x and y
{0.5f, 2.f}, // aspect ratio narrows, downscale x and upscale y
{2.f, 0.5f} // aspect ratio widens, upscale x and downscale y
};
auto map2d = [&](const SkM44& m, SkV2 p) {
SkV4 mapped = m.map(p.x, p.y, 0.f, 1.f);
REPORTER_ASSERT(reporter, mapped.z == 0.f);
REPORTER_ASSERT(reporter, mapped.w == 1.f);
return SkV2{mapped.x, mapped.y};
};
auto assertNearlyEqual = [&](float actual, float expected) {
REPORTER_ASSERT(reporter, SkScalarNearlyEqual(actual, expected),
"Expected %g == %g", actual, expected);
};
auto assertEdges = [&](float actualLow, float actualHigh,
float expectedLow, float expectedHigh) {
SkASSERT(expectedLow < expectedHigh);
REPORTER_ASSERT(reporter, actualLow < actualHigh,
"Expected %g < %g", actualLow, actualHigh);
assertNearlyEqual(actualLow, expectedLow);
assertNearlyEqual(actualHigh, expectedHigh);
};
SkRandom rand;
for (const auto& r : dstScales) {
SkRect src = SkRect::MakeXYWH(rand.nextRangeF(-10.f, 10.f),
rand.nextRangeF(-10.f, 10.f),
rand.nextRangeF(1.f, 10.f),
rand.nextRangeF(1.f, 10.f));
SkRect dst = SkRect::MakeXYWH(rand.nextRangeF(-10.f, 10.f),
rand.nextRangeF(-10.f, 10.f),
r.x * src.width(),
r.y * src.height());
SkM44 m = SkM44::RectToRect(src, dst);
// Regardless of the factory, center of src maps to center of dst
SkV2 center = map2d(m, {src.centerX(), src.centerY()});
assertNearlyEqual(center.x, dst.centerX());
assertNearlyEqual(center.y, dst.centerY());
// Map the four corners of src and validate against expected edge mapping
SkV2 tl = map2d(m, {src.fLeft, src.fTop});
SkV2 tr = map2d(m, {src.fRight, src.fTop});
SkV2 br = map2d(m, {src.fRight, src.fBottom});
SkV2 bl = map2d(m, {src.fLeft, src.fBottom});
assertEdges(tl.x, tr.x, dst.fLeft, dst.fRight);
assertEdges(bl.x, br.x, dst.fLeft, dst.fRight);
assertEdges(tl.y, bl.y, dst.fTop, dst.fBottom);
assertEdges(tr.y, br.y, dst.fTop, dst.fBottom);
}
}
DEF_TEST(M44_mapRect, reporter) {
auto assertRectsNearlyEqual = [&](const SkRect& actual, const SkRect& expected,
const SkRect& e) {
REPORTER_ASSERT(reporter, SkScalarNearlyEqual(actual.fLeft, expected.fLeft, e.fLeft),
"Expected %g == %g", actual.fLeft, expected.fLeft);
REPORTER_ASSERT(reporter, SkScalarNearlyEqual(actual.fTop, expected.fTop, e.fTop),
"Expected %g == %g", actual.fTop, expected.fTop);
REPORTER_ASSERT(reporter, SkScalarNearlyEqual(actual.fRight, expected.fRight, e.fRight),
"Expected %g == %g", actual.fRight, expected.fRight);
REPORTER_ASSERT(reporter, SkScalarNearlyEqual(actual.fBottom, expected.fBottom, e.fBottom),
"Expected %g == %g", actual.fBottom, expected.fBottom);
};
auto assertMapRect = [&](const SkM44& m, const SkRect& src, const SkRect* expected) {
SkRect epsilon = {1e-5f, 1e-5f, 1e-5f, 1e-5f};
SkRect actual = SkMatrixPriv::MapRect(m, src);
REPORTER_ASSERT(reporter, !actual.isEmpty());
if (expected) {
assertRectsNearlyEqual(actual, *expected, epsilon);
}
SkV4 corners[4] = {{src.fLeft, src.fTop, 0.f, 1.f},
{src.fRight, src.fTop, 0.f, 1.f},
{src.fRight, src.fBottom, 0.f, 1.f},
{src.fLeft, src.fBottom, 0.f, 1.f}};
bool leftFound = false;
bool topFound = false;
bool rightFound = false;
bool bottomFound = false;
bool clipped = false;
for (int i = 0; i < 4; ++i) {
SkV4 mapped = m * corners[i];
if (mapped.w > 0.f) {
// Should be contained in actual and might be on one or two of actual's edges
float x = mapped.x / mapped.w;
float y = mapped.y / mapped.w;
// Can't use SkRect::contains() since it treats right and bottom edges as exclusive
REPORTER_ASSERT(reporter, actual.fLeft <= x && x <= actual.fRight,
"Expected %g contained in [%g, %g]",
x, actual.fLeft, actual.fRight);
REPORTER_ASSERT(reporter, actual.fTop <= y && y <= actual.fBottom,
"Expected %g contained in [%g, %g]",
y, actual.fTop, actual.fBottom);
leftFound |= SkScalarNearlyEqual(x, actual.fLeft);
topFound |= SkScalarNearlyEqual(y, actual.fTop);
rightFound |= SkScalarNearlyEqual(x, actual.fRight);
bottomFound |= SkScalarNearlyEqual(y, actual.fBottom);
} else {
// The mapped point would be clipped so the clipped mapped bounds don't necessarily
// contain it
clipped = true;
}
}
if (clipped) {
// At least one of the mapped corners should have contributed to the rect
REPORTER_ASSERT(reporter, leftFound || topFound || rightFound || bottomFound);
// For any edge that came from a clipped corner, increase its error tolerance relative
// to what SkPath::ApplyPerspectiveClip calculates.
// TODO(michaelludwig): skbug.com/12335 required updating the w epsilon distance which
// greatly increased noise for coords projecting to infinity. They aren't "wrong", since
// the intent was clearly to pick a big number that's definitely offscreen, but
// MapRect should have a more robust solution than a fixed w > epsilon and when it does,
// these expectations for clipped points should be more accurate.
if (!leftFound) { epsilon.fLeft = .01f * actual.fLeft; }
if (!topFound) { epsilon.fTop = .01f * actual.fTop; }
if (!rightFound) { epsilon.fRight = .01f * actual.fRight; }
if (!bottomFound) { epsilon.fBottom = .01f * actual.fBottom; }
} else {
// The mapped corners should have contributed to all four edges of the returned rect
REPORTER_ASSERT(reporter, leftFound && topFound && rightFound && bottomFound);
}
SkPath path = SkPath::Rect(src);
path.transform(m.asM33(), SkApplyPerspectiveClip::kYes);
assertRectsNearlyEqual(actual, path.getBounds(), epsilon);
};
// src chosen arbitrarily
const SkRect src = SkRect::MakeLTRB(4.83f, -0.48f, 5.53f, 30.68f);
// Identity maps src to src
assertMapRect(SkM44(), src, &src);
// Scale+Translate just offsets src
SkRect st = SkRect::MakeLTRB(10.f + 2.f * src.fLeft, 8.f + 4.f * src.fTop,
10.f + 2.f * src.fRight, 8.f + 4.f * src.fBottom);
assertMapRect(SkM44::Scale(2.f, 4.f).postTranslate(10.f, 8.f), src, &st);
// Rotate 45 degrees about center
assertMapRect(SkM44::Rotate({0.f, 0.f, 1.f}, SK_ScalarPI / 4.f)
.preTranslate(-src.centerX(), -src.centerY())
.postTranslate(src.centerX(), src.centerY()),
src, nullptr);
// Perspective matrix where src does not need to be clipped w > 0
SkM44 p = SkM44::Perspective(0.01f, 10.f, SK_ScalarPI / 3.f);
p.preTranslate(0.f, 5.f, -0.1f);
p.preConcat(SkM44::Rotate({0.f, 1.f, 0.f}, 0.008f /* radians */));
assertMapRect(p, src, nullptr);
// Perspective matrix where src *does* need to be clipped w > 0
p.setIdentity();
p.setRow(3, {-.2f, -.6f, 0.f, 8.f});
assertMapRect(p, src, nullptr);
}
DEF_TEST(M44_mapRect_skbug12335, r) {
// Stripped down test case from skbug.com/12335. Essentially, the corners of this rect would
// map to homogoneous coords with very small w's (below the old value of kW0PlaneDistance) and
// so they would be clipped "behind" the plane, resulting in an empty mapped rect. Coordinates
// with positive that wouldn't overflow when divided by w should still be included in the mapped
// rectangle.
SkRect rect = SkRect::MakeLTRB(0, 0, 319, 620);
SkM44 m(SkMatrix::MakeAll( 0.000152695269f, 0.00000000f, -6.53848401e-05f,
-1.75697533e-05f, 0.000157153074f, -1.10847975e-06f,
-6.00415362e-08f, 0.00000000f, 0.000169880834f));
SkRect out = SkMatrixPriv::MapRect(m, rect);
REPORTER_ASSERT(r, !out.isEmpty());
}