skia2/tests/GeometryTest.cpp

237 lines
8.0 KiB
C++

/*
* Copyright 2011 Google Inc.
*
* Use of this source code is governed by a BSD-style license that can be
* found in the LICENSE file.
*/
#include "SkGeometry.h"
#include "Test.h"
#include "SkRandom.h"
static bool nearly_equal(const SkPoint& a, const SkPoint& b) {
return SkScalarNearlyEqual(a.fX, b.fX) && SkScalarNearlyEqual(a.fY, b.fY);
}
static void testChopCubic(skiatest::Reporter* reporter) {
/*
Inspired by this test, which used to assert that the tValues had dups
<path stroke="#202020" d="M0,0 C0,0 1,1 2190,5130 C2190,5070 2220,5010 2205,4980" />
*/
const SkPoint src[] = {
{ SkIntToScalar(2190), SkIntToScalar(5130) },
{ SkIntToScalar(2190), SkIntToScalar(5070) },
{ SkIntToScalar(2220), SkIntToScalar(5010) },
{ SkIntToScalar(2205), SkIntToScalar(4980) },
};
SkPoint dst[13];
SkScalar tValues[3];
// make sure we don't assert internally
int count = SkChopCubicAtMaxCurvature(src, dst, tValues);
if (false) { // avoid bit rot, suppress warning
REPORTER_ASSERT(reporter, count);
}
}
static void check_pairs(skiatest::Reporter* reporter, int index, SkScalar t, const char name[],
SkScalar x0, SkScalar y0, SkScalar x1, SkScalar y1) {
bool eq = SkScalarNearlyEqual(x0, x1) && SkScalarNearlyEqual(y0, y1);
if (!eq) {
SkDebugf("%s [%d %g] p0 [%10.8f %10.8f] p1 [%10.8f %10.8f]\n",
name, index, t, x0, y0, x1, y1);
REPORTER_ASSERT(reporter, eq);
}
}
static void test_evalquadat(skiatest::Reporter* reporter) {
SkRandom rand;
for (int i = 0; i < 1000; ++i) {
SkPoint pts[3];
for (int j = 0; j < 3; ++j) {
pts[j].set(rand.nextSScalar1() * 100, rand.nextSScalar1() * 100);
}
const SkScalar dt = SK_Scalar1 / 128;
SkScalar t = dt;
for (int j = 1; j < 128; ++j) {
SkPoint r0;
SkEvalQuadAt(pts, t, &r0);
SkPoint r1 = SkEvalQuadAt(pts, t);
check_pairs(reporter, i, t, "quad-pos", r0.fX, r0.fY, r1.fX, r1.fY);
SkVector v0;
SkEvalQuadAt(pts, t, nullptr, &v0);
SkVector v1 = SkEvalQuadTangentAt(pts, t);
check_pairs(reporter, i, t, "quad-tan", v0.fX, v0.fY, v1.fX, v1.fY);
t += dt;
}
}
}
static void test_conic_eval_pos(skiatest::Reporter* reporter, const SkConic& conic, SkScalar t) {
SkPoint p0, p1;
conic.evalAt(t, &p0, nullptr);
p1 = conic.evalAt(t);
check_pairs(reporter, 0, t, "conic-pos", p0.fX, p0.fY, p1.fX, p1.fY);
}
static void test_conic_eval_tan(skiatest::Reporter* reporter, const SkConic& conic, SkScalar t) {
SkVector v0, v1;
conic.evalAt(t, nullptr, &v0);
v1 = conic.evalTangentAt(t);
check_pairs(reporter, 0, t, "conic-tan", v0.fX, v0.fY, v1.fX, v1.fY);
}
static void test_conic(skiatest::Reporter* reporter) {
SkRandom rand;
for (int i = 0; i < 1000; ++i) {
SkPoint pts[3];
for (int j = 0; j < 3; ++j) {
pts[j].set(rand.nextSScalar1() * 100, rand.nextSScalar1() * 100);
}
for (int k = 0; k < 10; ++k) {
SkScalar w = rand.nextUScalar1() * 2;
SkConic conic(pts, w);
const SkScalar dt = SK_Scalar1 / 128;
SkScalar t = dt;
for (int j = 1; j < 128; ++j) {
test_conic_eval_pos(reporter, conic, t);
test_conic_eval_tan(reporter, conic, t);
t += dt;
}
}
}
}
static void test_quad_tangents(skiatest::Reporter* reporter) {
SkPoint pts[] = {
{10, 20}, {10, 20}, {20, 30},
{10, 20}, {15, 25}, {20, 30},
{10, 20}, {20, 30}, {20, 30},
};
int count = (int) SK_ARRAY_COUNT(pts) / 3;
for (int index = 0; index < count; ++index) {
SkConic conic(&pts[index * 3], 0.707f);
SkVector start = SkEvalQuadTangentAt(&pts[index * 3], 0);
SkVector mid = SkEvalQuadTangentAt(&pts[index * 3], .5f);
SkVector end = SkEvalQuadTangentAt(&pts[index * 3], 1);
REPORTER_ASSERT(reporter, start.fX && start.fY);
REPORTER_ASSERT(reporter, mid.fX && mid.fY);
REPORTER_ASSERT(reporter, end.fX && end.fY);
REPORTER_ASSERT(reporter, SkScalarNearlyZero(start.cross(mid)));
REPORTER_ASSERT(reporter, SkScalarNearlyZero(mid.cross(end)));
}
}
static void test_conic_tangents(skiatest::Reporter* reporter) {
SkPoint pts[] = {
{ 10, 20}, {10, 20}, {20, 30},
{ 10, 20}, {15, 25}, {20, 30},
{ 10, 20}, {20, 30}, {20, 30}
};
int count = (int) SK_ARRAY_COUNT(pts) / 3;
for (int index = 0; index < count; ++index) {
SkConic conic(&pts[index * 3], 0.707f);
SkVector start = conic.evalTangentAt(0);
SkVector mid = conic.evalTangentAt(.5f);
SkVector end = conic.evalTangentAt(1);
REPORTER_ASSERT(reporter, start.fX && start.fY);
REPORTER_ASSERT(reporter, mid.fX && mid.fY);
REPORTER_ASSERT(reporter, end.fX && end.fY);
REPORTER_ASSERT(reporter, SkScalarNearlyZero(start.cross(mid)));
REPORTER_ASSERT(reporter, SkScalarNearlyZero(mid.cross(end)));
}
}
static void test_this_conic_to_quad(skiatest::Reporter* r, const SkPoint pts[3], SkScalar w) {
SkAutoConicToQuads quadder;
const SkPoint* qpts = quadder.computeQuads(pts, w, 0.25);
const int qcount = quadder.countQuads();
const int pcount = qcount * 2 + 1;
REPORTER_ASSERT(r, SkPointsAreFinite(qpts, pcount));
}
/**
* We need to ensure that when a conic is approximated by quads, that we always return finite
* values in the quads.
*
* Inspired by crbug_627414
*/
static void test_conic_to_quads(skiatest::Reporter* reporter) {
const SkPoint triples[] = {
{ 0, 0 }, { 1, 0 }, { 1, 1 },
{ 0, 0 }, { 3.58732e-43f, 2.72084f }, { 3.00392f, 3.00392f },
{ 0, 0 }, { 100000, 0 }, { 100000, 100000 },
{ 0, 0 }, { 1e30f, 0 }, { 1e30f, 1e30f },
};
const int N = sizeof(triples) / sizeof(SkPoint);
for (int i = 0; i < N; i += 3) {
const SkPoint* pts = &triples[i];
SkRect bounds;
bounds.set(pts, 3);
SkScalar w = 1e30f;
do {
w *= 2;
test_this_conic_to_quad(reporter, pts, w);
} while (SkScalarIsFinite(w));
test_this_conic_to_quad(reporter, pts, SK_ScalarNaN);
}
}
static void test_cubic_tangents(skiatest::Reporter* reporter) {
SkPoint pts[] = {
{ 10, 20}, {10, 20}, {20, 30}, {30, 40},
{ 10, 20}, {15, 25}, {20, 30}, {30, 40},
{ 10, 20}, {20, 30}, {30, 40}, {30, 40},
};
int count = (int) SK_ARRAY_COUNT(pts) / 4;
for (int index = 0; index < count; ++index) {
SkConic conic(&pts[index * 3], 0.707f);
SkVector start, mid, end;
SkEvalCubicAt(&pts[index * 4], 0, nullptr, &start, nullptr);
SkEvalCubicAt(&pts[index * 4], .5f, nullptr, &mid, nullptr);
SkEvalCubicAt(&pts[index * 4], 1, nullptr, &end, nullptr);
REPORTER_ASSERT(reporter, start.fX && start.fY);
REPORTER_ASSERT(reporter, mid.fX && mid.fY);
REPORTER_ASSERT(reporter, end.fX && end.fY);
REPORTER_ASSERT(reporter, SkScalarNearlyZero(start.cross(mid)));
REPORTER_ASSERT(reporter, SkScalarNearlyZero(mid.cross(end)));
}
}
DEF_TEST(Geometry, reporter) {
SkPoint pts[3], dst[5];
pts[0].set(0, 0);
pts[1].set(100, 50);
pts[2].set(0, 100);
int count = SkChopQuadAtMaxCurvature(pts, dst);
REPORTER_ASSERT(reporter, count == 1 || count == 2);
pts[0].set(0, 0);
pts[1].set(3, 0);
pts[2].set(3, 3);
SkConvertQuadToCubic(pts, dst);
const SkPoint cubic[] = {
{ 0, 0, }, { 2, 0, }, { 3, 1, }, { 3, 3 },
};
for (int i = 0; i < 4; ++i) {
REPORTER_ASSERT(reporter, nearly_equal(cubic[i], dst[i]));
}
testChopCubic(reporter);
test_evalquadat(reporter);
test_conic(reporter);
test_cubic_tangents(reporter);
test_quad_tangents(reporter);
test_conic_tangents(reporter);
test_conic_to_quads(reporter);
}