1 /*
2 * Copyright 2011 Google Inc.
3 *
4 * Use of this source code is governed by a BSD-style license that can be
5 * found in the LICENSE file.
6 */
7
8 #include "include/core/SkMatrix.h"
9 #include "include/core/SkPoint.h"
10 #include "include/core/SkScalar.h"
11 #include "include/core/SkSpan.h"
12 #include "include/core/SkTypes.h"
13 #include "include/private/base/SkDebug.h"
14 #include "src/base/SkRandom.h"
15 #include "src/core/SkGeometry.h"
16 #include "src/core/SkPointPriv.h"
17 #include "tests/Test.h"
18
19 #include <array>
20 #include <cmath>
21 #include <cstdlib>
22 #include <limits>
23 #include <string>
24
nearly_equal(const SkPoint & a,const SkPoint & b)25 static bool nearly_equal(const SkPoint& a, const SkPoint& b) {
26 return SkScalarNearlyEqual(a.fX, b.fX) && SkScalarNearlyEqual(a.fY, b.fY);
27 }
28
testChopCubic(skiatest::Reporter * reporter)29 static void testChopCubic(skiatest::Reporter* reporter) {
30 /*
31 Inspired by this test, which used to assert that the tValues had dups
32
33 <path stroke="#202020" d="M0,0 C0,0 1,1 2190,5130 C2190,5070 2220,5010 2205,4980" />
34 */
35 const SkPoint src[] = {
36 { SkIntToScalar(2190), SkIntToScalar(5130) },
37 { SkIntToScalar(2190), SkIntToScalar(5070) },
38 { SkIntToScalar(2220), SkIntToScalar(5010) },
39 { SkIntToScalar(2205), SkIntToScalar(4980) },
40 };
41 SkPoint dst[13];
42 SkScalar tValues[3];
43 // make sure we don't assert internally
44 int count = SkChopCubicAtMaxCurvature(src, dst, tValues);
45 if ((false)) { // avoid bit rot, suppress warning
46 REPORTER_ASSERT(reporter, count);
47 }
48 // Make sure src and dst can be the same pointer.
49 {
50 SkPoint pts[7];
51 for (int i = 0; i < 7; ++i) {
52 pts[i].set(i, i);
53 }
54 SkChopCubicAt(pts, pts, .5f);
55 for (int i = 0; i < 7; ++i) {
56 REPORTER_ASSERT(reporter, pts[i].fX == pts[i].fY);
57 REPORTER_ASSERT(reporter, pts[i].fX == i * .5f);
58 }
59 }
60
61 static const float chopTs[] = {
62 0, 3/83.f, 3/79.f, 3/73.f, 3/71.f, 3/67.f, 3/61.f, 3/59.f, 3/53.f, 3/47.f, 3/43.f, 3/41.f,
63 3/37.f, 3/31.f, 3/29.f, 3/23.f, 3/19.f, 3/17.f, 3/13.f, 3/11.f, 3/7.f, 3/5.f, 1,
64 };
65 float ones[] = {1,1,1,1,1};
66
67 // Ensure an odd number of T values so we exercise the single chop code at the end of
68 // SkChopCubicAt form multiple T.
69 static_assert(std::size(chopTs) % 2 == 1);
70 static_assert(std::size(ones) % 2 == 1);
71
72 SkRandom rand;
73 for (int iterIdx = 0; iterIdx < 5; ++iterIdx) {
74 SkPoint pts[4] = {{rand.nextF(), rand.nextF()}, {rand.nextF(), rand.nextF()},
75 {rand.nextF(), rand.nextF()}, {rand.nextF(), rand.nextF()}};
76
77 SkPoint allChops[4 + std::size(chopTs)*3];
78 SkChopCubicAt(pts, allChops, chopTs, std::size(chopTs));
79 int i = 3;
80 for (float chopT : chopTs) {
81 // Ensure we chop at approximately the correct points when we chop an entire list.
82 SkPoint expectedPt;
83 SkEvalCubicAt(pts, chopT, &expectedPt, nullptr, nullptr);
84 REPORTER_ASSERT(reporter, SkScalarNearlyEqual(allChops[i].x(), expectedPt.x()));
85 REPORTER_ASSERT(reporter, SkScalarNearlyEqual(allChops[i].y(), expectedPt.y()));
86 if (chopT == 0) {
87 REPORTER_ASSERT(reporter, allChops[i] == pts[0]);
88 }
89 if (chopT == 1) {
90 REPORTER_ASSERT(reporter, allChops[i] == pts[3]);
91 }
92 i += 3;
93
94 // Ensure the middle is exactly degenerate when we chop at two equal points.
95 SkPoint localChops[10];
96 SkChopCubicAt(pts, localChops, chopT, chopT);
97 REPORTER_ASSERT(reporter, localChops[3] == localChops[4]);
98 REPORTER_ASSERT(reporter, localChops[3] == localChops[5]);
99 REPORTER_ASSERT(reporter, localChops[3] == localChops[6]);
100 if (chopT == 0) {
101 // Also ensure the first curve is exactly p0 when we chop at T=0.
102 REPORTER_ASSERT(reporter, localChops[0] == pts[0]);
103 REPORTER_ASSERT(reporter, localChops[1] == pts[0]);
104 REPORTER_ASSERT(reporter, localChops[2] == pts[0]);
105 REPORTER_ASSERT(reporter, localChops[3] == pts[0]);
106 }
107 if (chopT == 1) {
108 // Also ensure the last curve is exactly p3 when we chop at T=1.
109 REPORTER_ASSERT(reporter, localChops[6] == pts[3]);
110 REPORTER_ASSERT(reporter, localChops[7] == pts[3]);
111 REPORTER_ASSERT(reporter, localChops[8] == pts[3]);
112 REPORTER_ASSERT(reporter, localChops[9] == pts[3]);
113 }
114 }
115
116 // Now test what happens when SkChopCubicAt does 0/0 and gets NaN values.
117 SkPoint oneChops[4 + std::size(ones)*3];
118 SkChopCubicAt(pts, oneChops, ones, std::size(ones));
119 REPORTER_ASSERT(reporter, oneChops[0] == pts[0]);
120 REPORTER_ASSERT(reporter, oneChops[1] == pts[1]);
121 REPORTER_ASSERT(reporter, oneChops[2] == pts[2]);
122 for (size_t index = 3; index < std::size(oneChops); ++index) {
123 REPORTER_ASSERT(reporter, oneChops[index] == pts[3]);
124 }
125 }
126 }
127
check_pairs(skiatest::Reporter * reporter,int index,SkScalar t,const char name[],SkScalar x0,SkScalar y0,SkScalar x1,SkScalar y1)128 static void check_pairs(skiatest::Reporter* reporter, int index, SkScalar t, const char name[],
129 SkScalar x0, SkScalar y0, SkScalar x1, SkScalar y1) {
130 bool eq = SkScalarNearlyEqual(x0, x1) && SkScalarNearlyEqual(y0, y1);
131 if (!eq) {
132 SkDebugf("%s [%d %g] p0 [%10.8f %10.8f] p1 [%10.8f %10.8f]\n",
133 name, index, t, x0, y0, x1, y1);
134 REPORTER_ASSERT(reporter, eq);
135 }
136 }
137
test_evalquadat(skiatest::Reporter * reporter)138 static void test_evalquadat(skiatest::Reporter* reporter) {
139 SkRandom rand;
140 for (int i = 0; i < 1000; ++i) {
141 SkPoint pts[3];
142 for (int j = 0; j < 3; ++j) {
143 pts[j].set(rand.nextSScalar1() * 100, rand.nextSScalar1() * 100);
144 }
145 const SkScalar dt = SK_Scalar1 / 128;
146 SkScalar t = dt;
147 for (int j = 1; j < 128; ++j) {
148 SkPoint r0;
149 SkEvalQuadAt(pts, t, &r0);
150 SkPoint r1 = SkEvalQuadAt(pts, t);
151 check_pairs(reporter, i, t, "quad-pos", r0.fX, r0.fY, r1.fX, r1.fY);
152
153 SkVector v0;
154 SkEvalQuadAt(pts, t, nullptr, &v0);
155 SkVector v1 = SkEvalQuadTangentAt(pts, t);
156 check_pairs(reporter, i, t, "quad-tan", v0.fX, v0.fY, v1.fX, v1.fY);
157
158 t += dt;
159 }
160 }
161 }
162
test_conic_eval_pos(skiatest::Reporter * reporter,const SkConic & conic,SkScalar t)163 static void test_conic_eval_pos(skiatest::Reporter* reporter, const SkConic& conic, SkScalar t) {
164 SkPoint p0, p1;
165 conic.evalAt(t, &p0, nullptr);
166 p1 = conic.evalAt(t);
167 check_pairs(reporter, 0, t, "conic-pos", p0.fX, p0.fY, p1.fX, p1.fY);
168 }
169
test_conic_eval_tan(skiatest::Reporter * reporter,const SkConic & conic,SkScalar t)170 static void test_conic_eval_tan(skiatest::Reporter* reporter, const SkConic& conic, SkScalar t) {
171 SkVector v0, v1;
172 conic.evalAt(t, nullptr, &v0);
173 v1 = conic.evalTangentAt(t);
174 check_pairs(reporter, 0, t, "conic-tan", v0.fX, v0.fY, v1.fX, v1.fY);
175 }
176
test_conic(skiatest::Reporter * reporter)177 static void test_conic(skiatest::Reporter* reporter) {
178 SkRandom rand;
179 for (int i = 0; i < 1000; ++i) {
180 SkPoint pts[3];
181 for (int j = 0; j < 3; ++j) {
182 pts[j].set(rand.nextSScalar1() * 100, rand.nextSScalar1() * 100);
183 }
184 for (int k = 0; k < 10; ++k) {
185 SkScalar w = rand.nextUScalar1() * 2;
186 SkConic conic(pts, w);
187
188 const SkScalar dt = SK_Scalar1 / 128;
189 SkScalar t = dt;
190 for (int j = 1; j < 128; ++j) {
191 test_conic_eval_pos(reporter, conic, t);
192 test_conic_eval_tan(reporter, conic, t);
193 t += dt;
194 }
195 }
196 }
197 }
198
test_quad_tangents(skiatest::Reporter * reporter)199 static void test_quad_tangents(skiatest::Reporter* reporter) {
200 SkPoint pts[] = {
201 {10, 20}, {10, 20}, {20, 30},
202 {10, 20}, {15, 25}, {20, 30},
203 {10, 20}, {20, 30}, {20, 30},
204 };
205 int count = (int) std::size(pts) / 3;
206 for (int index = 0; index < count; ++index) {
207 SkConic conic(&pts[index * 3], 0.707f);
208 SkVector start = SkEvalQuadTangentAt(&pts[index * 3], 0);
209 SkVector mid = SkEvalQuadTangentAt(&pts[index * 3], .5f);
210 SkVector end = SkEvalQuadTangentAt(&pts[index * 3], 1);
211 REPORTER_ASSERT(reporter, start.fX && start.fY);
212 REPORTER_ASSERT(reporter, mid.fX && mid.fY);
213 REPORTER_ASSERT(reporter, end.fX && end.fY);
214 REPORTER_ASSERT(reporter, SkScalarNearlyZero(start.cross(mid)));
215 REPORTER_ASSERT(reporter, SkScalarNearlyZero(mid.cross(end)));
216 }
217 }
218
test_conic_tangents(skiatest::Reporter * reporter)219 static void test_conic_tangents(skiatest::Reporter* reporter) {
220 SkPoint pts[] = {
221 { 10, 20}, {10, 20}, {20, 30},
222 { 10, 20}, {15, 25}, {20, 30},
223 { 10, 20}, {20, 30}, {20, 30}
224 };
225 int count = (int) std::size(pts) / 3;
226 for (int index = 0; index < count; ++index) {
227 SkConic conic(&pts[index * 3], 0.707f);
228 SkVector start = conic.evalTangentAt(0);
229 SkVector mid = conic.evalTangentAt(.5f);
230 SkVector end = conic.evalTangentAt(1);
231 REPORTER_ASSERT(reporter, start.fX && start.fY);
232 REPORTER_ASSERT(reporter, mid.fX && mid.fY);
233 REPORTER_ASSERT(reporter, end.fX && end.fY);
234 REPORTER_ASSERT(reporter, SkScalarNearlyZero(start.cross(mid)));
235 REPORTER_ASSERT(reporter, SkScalarNearlyZero(mid.cross(end)));
236 }
237 }
238
test_this_conic_to_quad(skiatest::Reporter * r,const SkPoint pts[3],SkScalar w)239 static void test_this_conic_to_quad(skiatest::Reporter* r, const SkPoint pts[3], SkScalar w) {
240 SkAutoConicToQuads quadder;
241 const SkPoint* qpts = quadder.computeQuads(pts, w, 0.25);
242 const int qcount = quadder.countQuads();
243 const int pcount = qcount * 2 + 1;
244
245 REPORTER_ASSERT(r, SkPointPriv::AreFinite(qpts, pcount));
246 }
247
248 /**
249 * We need to ensure that when a conic is approximated by quads, that we always return finite
250 * values in the quads.
251 *
252 * Inspired by crbug_627414
253 */
test_conic_to_quads(skiatest::Reporter * reporter)254 static void test_conic_to_quads(skiatest::Reporter* reporter) {
255 const SkPoint triples[] = {
256 { 0, 0 }, { 1, 0 }, { 1, 1 },
257 { 0, 0 }, { 3.58732e-43f, 2.72084f }, { 3.00392f, 3.00392f },
258 { 0, 0 }, { 100000, 0 }, { 100000, 100000 },
259 { 0, 0 }, { 1e30f, 0 }, { 1e30f, 1e30f },
260 };
261 const int N = sizeof(triples) / sizeof(SkPoint);
262
263 for (int i = 0; i < N; i += 3) {
264 const SkPoint* pts = &triples[i];
265
266 SkScalar w = 1e30f;
267 do {
268 w *= 2;
269 test_this_conic_to_quad(reporter, pts, w);
270 } while (SkScalarIsFinite(w));
271 test_this_conic_to_quad(reporter, pts, SK_ScalarNaN);
272 }
273 }
274
test_cubic_tangents(skiatest::Reporter * reporter)275 static void test_cubic_tangents(skiatest::Reporter* reporter) {
276 SkPoint pts[] = {
277 { 10, 20}, {10, 20}, {20, 30}, {30, 40},
278 { 10, 20}, {15, 25}, {20, 30}, {30, 40},
279 { 10, 20}, {20, 30}, {30, 40}, {30, 40},
280 };
281 int count = (int) std::size(pts) / 4;
282 for (int index = 0; index < count; ++index) {
283 SkConic conic(&pts[index * 3], 0.707f);
284 SkVector start, mid, end;
285 SkEvalCubicAt(&pts[index * 4], 0, nullptr, &start, nullptr);
286 SkEvalCubicAt(&pts[index * 4], .5f, nullptr, &mid, nullptr);
287 SkEvalCubicAt(&pts[index * 4], 1, nullptr, &end, nullptr);
288 REPORTER_ASSERT(reporter, start.fX && start.fY);
289 REPORTER_ASSERT(reporter, mid.fX && mid.fY);
290 REPORTER_ASSERT(reporter, end.fX && end.fY);
291 REPORTER_ASSERT(reporter, SkScalarNearlyZero(start.cross(mid)));
292 REPORTER_ASSERT(reporter, SkScalarNearlyZero(mid.cross(end)));
293 }
294 }
295
check_cubic_type(skiatest::Reporter * reporter,const std::array<SkPoint,4> & bezierPoints,SkCubicType expectedType,bool undefined=false)296 static void check_cubic_type(skiatest::Reporter* reporter,
297 const std::array<SkPoint, 4>& bezierPoints, SkCubicType expectedType,
298 bool undefined = false) {
299 // Classify the cubic even if the results will be undefined: check for crashes and asserts.
300 SkCubicType actualType = SkClassifyCubic(bezierPoints.data());
301 if (!undefined) {
302 REPORTER_ASSERT(reporter, actualType == expectedType);
303 }
304 }
305
check_cubic_around_rect(skiatest::Reporter * reporter,float x1,float y1,float x2,float y2,bool undefined=false)306 static void check_cubic_around_rect(skiatest::Reporter* reporter,
307 float x1, float y1, float x2, float y2,
308 bool undefined = false) {
309 static constexpr SkCubicType expectations[24] = {
310 SkCubicType::kLoop,
311 SkCubicType::kCuspAtInfinity,
312 SkCubicType::kLocalCusp,
313 SkCubicType::kLocalCusp,
314 SkCubicType::kCuspAtInfinity,
315 SkCubicType::kLoop,
316 SkCubicType::kCuspAtInfinity,
317 SkCubicType::kLoop,
318 SkCubicType::kCuspAtInfinity,
319 SkCubicType::kLoop,
320 SkCubicType::kLocalCusp,
321 SkCubicType::kLocalCusp,
322 SkCubicType::kLocalCusp,
323 SkCubicType::kLocalCusp,
324 SkCubicType::kLoop,
325 SkCubicType::kCuspAtInfinity,
326 SkCubicType::kLoop,
327 SkCubicType::kCuspAtInfinity,
328 SkCubicType::kLoop,
329 SkCubicType::kCuspAtInfinity,
330 SkCubicType::kLocalCusp,
331 SkCubicType::kLocalCusp,
332 SkCubicType::kCuspAtInfinity,
333 SkCubicType::kLoop,
334 };
335 SkPoint points[] = {{x1, y1}, {x2, y1}, {x2, y2}, {x1, y2}};
336 std::array<SkPoint, 4> bezier;
337 for (int i=0; i < 4; ++i) {
338 bezier[0] = points[i];
339 for (int j=0; j < 3; ++j) {
340 int jidx = (j < i) ? j : j+1;
341 bezier[1] = points[jidx];
342 for (int k=0, kidx=0; k < 2; ++k, ++kidx) {
343 for (int n = 0; n < 2; ++n) {
344 kidx = (kidx == i || kidx == jidx) ? kidx+1 : kidx;
345 }
346 bezier[2] = points[kidx];
347 for (int l = 0; l < 4; ++l) {
348 if (l != i && l != jidx && l != kidx) {
349 bezier[3] = points[l];
350 break;
351 }
352 }
353 check_cubic_type(reporter, bezier, expectations[i*6 + j*2 + k], undefined);
354 }
355 }
356 }
357 for (int i=0; i < 4; ++i) {
358 bezier[0] = points[i];
359 for (int j=0; j < 3; ++j) {
360 int jidx = (j < i) ? j : j+1;
361 bezier[1] = points[jidx];
362 bezier[2] = points[jidx];
363 for (int k=0, kidx=0; k < 2; ++k, ++kidx) {
364 for (int n = 0; n < 2; ++n) {
365 kidx = (kidx == i || kidx == jidx) ? kidx+1 : kidx;
366 }
367 bezier[3] = points[kidx];
368 check_cubic_type(reporter, bezier, SkCubicType::kSerpentine, undefined);
369 }
370 }
371 }
372 }
373
374 static std::array<SkPoint, 4> kSerpentines[] = {
375 {{{149.325f, 107.705f}, {149.325f, 103.783f}, {151.638f, 100.127f}, {156.263f, 96.736f}}},
376 {{{225.694f, 223.15f}, {209.831f, 224.837f}, {195.994f, 230.237f}, {184.181f, 239.35f}}},
377 {{{4.873f, 5.581f}, {5.083f, 5.2783f}, {5.182f, 4.8593f}, {5.177f, 4.3242f}}},
378 {{{285.625f, 499.687f}, {411.625f, 808.188f}, {1064.62f, 135.688f}, {1042.63f, 585.187f}}}
379 };
380
381 static std::array<SkPoint, 4> kLoops[] = {
382 {{{635.625f, 614.687f}, {171.625f, 236.188f}, {1064.62f, 135.688f}, {516.625f, 570.187f}}},
383 {{{653.050f, 725.049f}, {663.000f, 176.000f}, {1189.000f, 508.000f}, {288.050f, 564.950f}}},
384 {{{631.050f, 478.049f}, {730.000f, 302.000f}, {870.000f, 350.000f}, {905.050f, 528.950f}}},
385 {{{631.050f, 478.0499f}, {221.000f, 230.000f}, {1265.000f, 451.000f}, {905.050f, 528.950f}}}
386 };
387
388 static std::array<SkPoint, 4> kLinearCubics[] = {
389 {{{0, 0}, {0, 1}, {0, 2}, {0, 3}}}, // 0-degree flat line.
390 {{{0, 0}, {1, 0}, {1, 0}, {0, 0}}}, // 180-degree flat line
391 {{{0, 1}, {0, 0}, {0, 2}, {0, 3}}}, // 180-degree flat line
392 {{{0, 1}, {0, 0}, {0, 3}, {0, 2}}}, // 360-degree flat line
393 {{{0, 0}, {2, 0}, {1, 0}, {64, 0}}}, // 360-degree flat line
394 {{{1, 0}, {0, 0}, {3, 0}, {-64, 0}}} // 360-degree flat line
395 };
396
test_classify_cubic(skiatest::Reporter * reporter)397 static void test_classify_cubic(skiatest::Reporter* reporter) {
398 for (const auto& serp : kSerpentines) {
399 check_cubic_type(reporter, serp, SkCubicType::kSerpentine);
400 }
401 for (const auto& loop : kLoops) {
402 check_cubic_type(reporter, loop, SkCubicType::kLoop);
403 }
404 for (const auto& loop : kLinearCubics) {
405 check_cubic_type(reporter, loop, SkCubicType::kLineOrPoint);
406 }
407 check_cubic_around_rect(reporter, 0, 0, 1, 1);
408 check_cubic_around_rect(reporter,
409 -std::numeric_limits<float>::max(),
410 -std::numeric_limits<float>::max(),
411 +std::numeric_limits<float>::max(),
412 +std::numeric_limits<float>::max());
413 check_cubic_around_rect(reporter, 1, 1,
414 +std::numeric_limits<float>::min(),
415 +std::numeric_limits<float>::max());
416 check_cubic_around_rect(reporter,
417 -std::numeric_limits<float>::min(),
418 -std::numeric_limits<float>::min(),
419 +std::numeric_limits<float>::min(),
420 +std::numeric_limits<float>::min());
421 check_cubic_around_rect(reporter, +1, -std::numeric_limits<float>::min(), -1, -1);
422 check_cubic_around_rect(reporter,
423 -std::numeric_limits<float>::infinity(),
424 -std::numeric_limits<float>::infinity(),
425 +std::numeric_limits<float>::infinity(),
426 +std::numeric_limits<float>::infinity(),
427 true);
428 check_cubic_around_rect(reporter, 0, 0, 1, +std::numeric_limits<float>::infinity(), true);
429 check_cubic_around_rect(reporter,
430 -std::numeric_limits<float>::quiet_NaN(),
431 -std::numeric_limits<float>::quiet_NaN(),
432 +std::numeric_limits<float>::quiet_NaN(),
433 +std::numeric_limits<float>::quiet_NaN(),
434 true);
435 check_cubic_around_rect(reporter, 0, 0, 1, +std::numeric_limits<float>::quiet_NaN(), true);
436 }
437
438 static std::array<SkPoint, 4> kCusps[] = {
439 {{{0, 0}, {1, 1}, {1, 0}, {0, 1}}},
440 {{{0, 0}, {1, 1}, {0, 1}, {1, 0}}},
441 {{{0, 1}, {1, 0}, {0, 0}, {1, 1}}},
442 {{{0, 1}, {1, 0}, {1, 1}, {0, 0}}},
443 };
444
test_cubic_cusps(skiatest::Reporter * reporter)445 static void test_cubic_cusps(skiatest::Reporter* reporter) {
446 std::array<SkPoint, 4> noCusps[] = {
447 {{{0, 0}, {1, 1}, {2, 2}, {3, 3}}},
448 {{{0, 0}, {1, 0}, {1, 1}, {0, 1}}},
449 {{{0, 0}, {1, 0}, {2, 1}, {2, 2}}},
450 {{{0, 0}, {1, 0}, {1, 1}, {2, 1}}},
451 };
452 for (auto noCusp : noCusps) {
453 REPORTER_ASSERT(reporter, SkFindCubicCusp(noCusp.data()) < 0);
454 }
455 for (auto cusp : kCusps) {
456 REPORTER_ASSERT(reporter, SkFindCubicCusp(cusp.data()) > 0);
457 }
458 }
459
460 static SkMatrix kSkewMatrices[] = {
461 SkMatrix::MakeAll(1,0,0, 0,1,0, 0,0,1),
462 SkMatrix::MakeAll(1,-1,0, 1,1,0, 0,0,1),
463 SkMatrix::MakeAll(.889f,.553f,0, -.443f,.123f,0, 0,0,1),
464 };
465
test_chop_quad_at_midtangent(skiatest::Reporter * reporter,const SkPoint pts[3])466 static void test_chop_quad_at_midtangent(skiatest::Reporter* reporter, const SkPoint pts[3]) {
467 constexpr float kTolerance = 1e-3f;
468 for (const SkMatrix& m : kSkewMatrices) {
469 SkPoint mapped[3];
470 m.mapPoints(mapped, pts, 3);
471 float fullRotation = SkMeasureQuadRotation(pts);
472 SkPoint chopped[5];
473 SkChopQuadAtMidTangent(pts, chopped);
474 float leftRotation = SkMeasureQuadRotation(chopped);
475 float rightRotation = SkMeasureQuadRotation(chopped+2);
476 REPORTER_ASSERT(reporter, SkScalarNearlyEqual(leftRotation, fullRotation/2, kTolerance));
477 REPORTER_ASSERT(reporter, SkScalarNearlyEqual(rightRotation, fullRotation/2, kTolerance));
478 }
479 }
480
test_chop_cubic_at_midtangent(skiatest::Reporter * reporter,const SkPoint pts[4],SkCubicType cubicType)481 static void test_chop_cubic_at_midtangent(skiatest::Reporter* reporter, const SkPoint pts[4],
482 SkCubicType cubicType) {
483 constexpr float kTolerance = 1e-3f;
484 int n = std::size(kSkewMatrices);
485 if (cubicType == SkCubicType::kLocalCusp || cubicType == SkCubicType::kLineOrPoint) {
486 // FP precision isn't always enough to get the exact correct T value of the mid-tangent on
487 // cusps and lines. Only test the identity matrix and the matrix with all 1's.
488 n = 2;
489 }
490 for (int i = 0; i < n; ++i) {
491 SkPoint mapped[4];
492 kSkewMatrices[i].mapPoints(mapped, pts, 4);
493 float fullRotation = SkMeasureNonInflectCubicRotation(mapped);
494 SkPoint chopped[7];
495 SkChopCubicAtMidTangent(mapped, chopped);
496 float leftRotation = SkMeasureNonInflectCubicRotation(chopped);
497 float rightRotation = SkMeasureNonInflectCubicRotation(chopped+3);
498 if (cubicType == SkCubicType::kLineOrPoint &&
499 (SkScalarNearlyEqual(fullRotation, 2*SK_ScalarPI, kTolerance) ||
500 SkScalarNearlyEqual(fullRotation, 0, kTolerance))) {
501 // 0- and 360-degree flat lines don't have single points of midtangent.
502 // (tangent == midtangent at every point on these curves except the cusp points.)
503 // Instead verify the promise from SkChopCubicAtMidTangent that neither side will rotate
504 // more than 180 degrees.
505 REPORTER_ASSERT(reporter, std::abs(leftRotation) - kTolerance <= SK_ScalarPI);
506 REPORTER_ASSERT(reporter, std::abs(rightRotation) - kTolerance <= SK_ScalarPI);
507 continue;
508 }
509 float expectedChoppedRotation = fullRotation/2;
510 if (cubicType == SkCubicType::kLocalCusp ||
511 (cubicType == SkCubicType::kLineOrPoint &&
512 SkScalarNearlyEqual(fullRotation, SK_ScalarPI, kTolerance))) {
513 // If we chop a cubic at a cusp, we lose 180 degrees of rotation.
514 expectedChoppedRotation = (fullRotation - SK_ScalarPI)/2;
515 }
516 REPORTER_ASSERT(reporter, SkScalarNearlyEqual(leftRotation, expectedChoppedRotation,
517 kTolerance));
518 REPORTER_ASSERT(reporter, SkScalarNearlyEqual(rightRotation, expectedChoppedRotation,
519 kTolerance));
520 }
521 }
522
523 static std::array<SkPoint, 3> kQuads[] = {
524 {{{10, 20}, {15, 35}, {30, 40}}},
525 {{{176.324f, 392.705f}, {719.325f, 205.782f}, {297.263f, 347.735f}}},
526 {{{652.050f, 602.049f}, {481.000f, 533.000f}, {288.050f, 564.950f}}},
527 {{{460.625f, 557.187f}, {707.121f, 209.688f}, {779.628f, 577.687f}}},
528 {{{359.050f, 578.049f}, {759.000f, 274.000f}, {288.050f, 564.950f}}}
529 };
530
lerp(const SkPoint & a,const SkPoint & b,float t)531 SkPoint lerp(const SkPoint& a, const SkPoint& b, float t) {
532 return a * (1 - t) + b * t;
533 }
534
test_measure_rotation(skiatest::Reporter * reporter)535 static void test_measure_rotation(skiatest::Reporter* reporter) {
536 static SkPoint kFlatCubic[4] = {{0, 0}, {0, 1}, {0, 2}, {0, 3}};
537 REPORTER_ASSERT(reporter, SkScalarNearlyZero(SkMeasureNonInflectCubicRotation(kFlatCubic)));
538
539 static SkPoint kFlatCubic180_1[4] = {{0, 0}, {1, 0}, {3, 0}, {2, 0}};
540 REPORTER_ASSERT(reporter, SkScalarNearlyEqual(SkMeasureNonInflectCubicRotation(kFlatCubic180_1),
541 SK_ScalarPI));
542
543 static SkPoint kFlatCubic180_2[4] = {{0, 1}, {0, 0}, {0, 2}, {0, 3}};
544 REPORTER_ASSERT(reporter, SkScalarNearlyEqual(SkMeasureNonInflectCubicRotation(kFlatCubic180_2),
545 SK_ScalarPI));
546
547 static SkPoint kFlatCubic360[4] = {{0, 1}, {0, 0}, {0, 3}, {0, 2}};
548 REPORTER_ASSERT(reporter, SkScalarNearlyEqual(SkMeasureNonInflectCubicRotation(kFlatCubic360),
549 2*SK_ScalarPI));
550
551 static SkPoint kSquare180[4] = {{0, 0}, {0, 1}, {1, 1}, {1, 0}};
552 REPORTER_ASSERT(reporter, SkScalarNearlyEqual(SkMeasureNonInflectCubicRotation(kSquare180),
553 SK_ScalarPI));
554
555 auto checkQuadRotation = [=](const SkPoint pts[3], float expectedRotation) {
556 float r = SkMeasureQuadRotation(pts);
557 REPORTER_ASSERT(reporter, SkScalarNearlyEqual(r, expectedRotation));
558
559 SkPoint cubic1[4] = {pts[0], pts[0], pts[1], pts[2]};
560 REPORTER_ASSERT(reporter, SkScalarNearlyEqual(SkMeasureNonInflectCubicRotation(cubic1),
561 expectedRotation));
562
563 SkPoint cubic2[4] = {pts[0], pts[1], pts[1], pts[2]};
564 REPORTER_ASSERT(reporter, SkScalarNearlyEqual(SkMeasureNonInflectCubicRotation(cubic2),
565 expectedRotation));
566
567 SkPoint cubic3[4] = {pts[0], pts[1], pts[2], pts[2]};
568 REPORTER_ASSERT(reporter, SkScalarNearlyEqual(SkMeasureNonInflectCubicRotation(cubic3),
569 expectedRotation));
570 };
571
572 static SkPoint kFlatQuad[4] = {{0, 0}, {0, 1}, {0, 2}};
573 checkQuadRotation(kFlatQuad, 0);
574
575 static SkPoint kFlatQuad180_1[4] = {{1, 0}, {0, 0}, {2, 0}};
576 checkQuadRotation(kFlatQuad180_1, SK_ScalarPI);
577
578 static SkPoint kFlatQuad180_2[4] = {{0, 0}, {0, 2}, {0, 1}};
579 checkQuadRotation(kFlatQuad180_2, SK_ScalarPI);
580
581 static SkPoint kTri120[3] = {{0, 0}, {.5f, std::sqrt(3.f)/2}, {1, 0}};
582 checkQuadRotation(kTri120, 2*SK_ScalarPI/3);
583 }
584
test_chop_at_midtangent(skiatest::Reporter * reporter)585 static void test_chop_at_midtangent(skiatest::Reporter* reporter) {
586 SkPoint chops[10];
587 for (const auto& serp : kSerpentines) {
588 REPORTER_ASSERT(reporter, SkClassifyCubic(serp.data()) == SkCubicType::kSerpentine);
589 int n = SkChopCubicAtInflections(serp.data(), chops);
590 for (int i = 0; i < n; ++i) {
591 test_chop_cubic_at_midtangent(reporter, chops + i*3, SkCubicType::kSerpentine);
592 }
593 }
594 for (const auto& loop : kLoops) {
595 REPORTER_ASSERT(reporter, SkClassifyCubic(loop.data()) == SkCubicType::kLoop);
596 test_chop_cubic_at_midtangent(reporter, loop.data(), SkCubicType::kLoop);
597 }
598 for (const auto& line : kLinearCubics) {
599 REPORTER_ASSERT(reporter, SkClassifyCubic(line.data()) == SkCubicType::kLineOrPoint);
600 test_chop_cubic_at_midtangent(reporter, line.data(), SkCubicType::kLineOrPoint);
601 }
602 for (const auto& cusp : kCusps) {
603 REPORTER_ASSERT(reporter, SkClassifyCubic(cusp.data()) == SkCubicType::kLocalCusp);
604 test_chop_cubic_at_midtangent(reporter, cusp.data(), SkCubicType::kLocalCusp);
605 }
606 for (const auto& quad : kQuads) {
607 test_chop_quad_at_midtangent(reporter, quad.data());
608 SkPoint asCubic[4] = {
609 quad[0], lerp(quad[0], quad[1], 2/3.f), lerp(quad[1], quad[2], 1/3.f), quad[2]};
610 test_chop_cubic_at_midtangent(reporter, asCubic, SkCubicType::kQuadratic);
611 }
612
613 static const SkPoint kExactQuad[4] = {{0,0}, {6,2}, {10,2}, {12,0}};
614 REPORTER_ASSERT(reporter, SkClassifyCubic(kExactQuad) == SkCubicType::kQuadratic);
615 test_chop_cubic_at_midtangent(reporter, kExactQuad, SkCubicType::kQuadratic);
616
617 static const SkPoint kExactCuspAtInf[4] = {{0,0}, {1,0}, {0,1}, {1,1}};
618 REPORTER_ASSERT(reporter, SkClassifyCubic(kExactCuspAtInf) == SkCubicType::kCuspAtInfinity);
619 int n = SkChopCubicAtInflections(kExactCuspAtInf, chops);
620 for (int i = 0; i < n; ++i) {
621 test_chop_cubic_at_midtangent(reporter, chops + i*3, SkCubicType::kCuspAtInfinity);
622 }
623 }
624
DEF_TEST(Geometry,reporter)625 DEF_TEST(Geometry, reporter) {
626 SkPoint pts[5];
627
628 pts[0].set(0, 0);
629 pts[1].set(100, 50);
630 pts[2].set(0, 100);
631
632 int count = SkChopQuadAtMaxCurvature(pts, pts); // Ensure src and dst can be the same pointer.
633 REPORTER_ASSERT(reporter, count == 1 || count == 2);
634
635 // This previously crashed because the computed t of max curvature is NaN and SkChopQuadAt
636 // asserts that the passed t is in 0..1. Passes by not asserting.
637 pts[0].set(15.1213f, 7.77647f);
638 pts[1].set(6.2168e+19f, 1.51338e+20f);
639 pts[2].set(1.4579e+19f, 1.55558e+21f);
640 count = SkChopQuadAtMaxCurvature(pts, pts);
641
642 pts[0].set(0, 0);
643 pts[1].set(3, 0);
644 pts[2].set(3, 3);
645 SkConvertQuadToCubic(pts, pts);
646 const SkPoint cubic[] = {
647 { 0, 0, }, { 2, 0, }, { 3, 1, }, { 3, 3 },
648 };
649 for (int i = 0; i < 4; ++i) {
650 REPORTER_ASSERT(reporter, nearly_equal(cubic[i], pts[i]));
651 }
652
653 testChopCubic(reporter);
654 test_evalquadat(reporter);
655 test_conic(reporter);
656 test_cubic_tangents(reporter);
657 test_quad_tangents(reporter);
658 test_conic_tangents(reporter);
659 test_conic_to_quads(reporter);
660 test_classify_cubic(reporter);
661 test_cubic_cusps(reporter);
662 test_measure_rotation(reporter);
663 test_chop_at_midtangent(reporter);
664 }
665
testChopMonoCubicAtY(skiatest::Reporter * reporter,std::string name,SkSpan<const SkPoint> curveInputs,SkScalar yToChopAt,SkSpan<const SkPoint> expectedOutputs)666 static void testChopMonoCubicAtY(skiatest::Reporter* reporter, std::string name,
667 SkSpan<const SkPoint> curveInputs, SkScalar yToChopAt,
668 SkSpan<const SkPoint> expectedOutputs) {
669 skiatest::ReporterContext subtest(reporter, name);
670 REPORTER_ASSERT(reporter, SkScalarNearlyEqual(expectedOutputs[3].y(), yToChopAt),
671 "Invalid test case. 4th point's Y should be %f", yToChopAt);
672
673 SkPoint outputs[7];
674 // Make sure it actually chopped
675 REPORTER_ASSERT(reporter, SkChopMonoCubicAtY(curveInputs.begin(), yToChopAt, outputs));
676
677 for (int i = 0; i < 7; ++i) {
678 REPORTER_ASSERT(reporter, nearly_equal(expectedOutputs[i], outputs[i]),
679 "(%f, %f) != (%f, %f) at index %d",
680 expectedOutputs[i].x(), expectedOutputs[i].y(),
681 outputs[i].x(), outputs[i].y(), i);
682 }
683 }
684
DEF_TEST(GeometryChopMonoCubicAtY_Successful,reporter)685 DEF_TEST(GeometryChopMonoCubicAtY_Successful, reporter) {
686 // These cubics are all arbitrary, picked using Desmos for something that looked "nice".
687
688 testChopMonoCubicAtY(reporter, "straight, positive slope @ 2.5",
689 {{ 0, 0 }, { 0, 0 }, { 10, 10 }, { 10, 10 }},
690 2.5f,
691 {{ 0.000000f, 0.000000f }, { 0.000000f, 0.000000f }, { 1.065055f, 1.065055f },
692 { 2.500000f, 2.500000f },
693 { 5.461981f, 5.461981f }, { 10.000000f, 10.000000f }, { 10.000000f, 10.000000f }}
694 );
695 testChopMonoCubicAtY(reporter, "straight, positive slope @ 5.0",
696 {{ 0, 0 }, { 0, 0 }, { 10, 10 }, { 10, 10 }},
697 5.0f,
698 {{ 0.000000f, 0.000000f }, { 0.000000f, 0.000000f }, { 2.500000f, 2.500000f },
699 { 5.000000f, 5.000000f },
700 { 7.500000f, 7.500000f }, { 10.000000f, 10.000000f }, { 10.000000f, 10.000000f }}
701 );
702 testChopMonoCubicAtY(reporter, "straight, positive slope @ 9.0",
703 {{ 0, 0 }, { 0, 0 }, { 10, 10 }, { 10, 10 }},
704 9.0f,
705 {{ 0.000000f, 0.000000f }, { 0.000000f, 0.000000f }, { 6.467375f, 6.467375f },
706 { 9.000000f, 9.000000f },
707 { 9.616623f, 9.616623f }, { 10.000000f, 10.000000f }, { 10.000000f, 10.000000f }}
708 );
709 testChopMonoCubicAtY(reporter, "straight, positive slope @ 10.0",
710 {{ 0, 0 }, { 0, 0 }, { 10, 10 }, { 10, 10 }},
711 10.0f,
712 {{ 0.000000f, 0.000000f }, { 0.000000f, 0.000000f }, { 10.000000f, 10.000000f },
713 { 10.000000f, 10.000000f },
714 { 10.000000f, 10.000000f }, { 10.000000f, 10.000000f }, { 10.000000f, 10.000000f }}
715 );
716
717 testChopMonoCubicAtY(reporter, "curve, positive slope @ 2.0",
718 {{ 1, 1 }, { 5, 2 }, { 7, 4 }, { 8, 7 }},
719 2.0f,
720 {{ 1.000000f, 1.000000f }, { 2.055050f, 1.263763f }, { 2.970959f, 1.597096f },
721 { 3.766077f, 2.000000f },
722 { 5.985480f, 3.124621f }, { 7.263762f, 4.791288f }, { 8.000000f, 7.000000f }}
723 );
724 testChopMonoCubicAtY(reporter, "curve, positive slope @ 5.0",
725 {{ 1, 1 }, { 5, 2 }, { 7, 4 }, { 8, 7 }},
726 5.0f,
727 {{ 1.000000f, 1.000000f }, { 4.033223f, 1.758306f }, { 5.916391f, 3.091639f },
728 { 7.085550f, 5.000000f },
729 { 7.458195f, 5.608251f }, { 7.758306f, 6.274917f }, { 8.000000f, 7.000000f }}
730 );
731
732 testChopMonoCubicAtY(reporter, "curve, negative slope @ 5.0",
733 {{ 2, 7 }, { 3, 2 }, { 6, 3 }, { 11, 2 }},
734 5.0f,
735 {{ 2.000000f, 7.000000f }, { 2.162856f, 6.185719f }, { 2.378757f, 5.530570f },
736 { 2.647702f, 5.000000f },
737 { 4.030182f, 2.272668f }, { 6.814281f, 2.837144f }, { 11.000000f, 2.000000f }}
738 );
739 testChopMonoCubicAtY(reporter, "curve, negative slope @ 3.0",
740 {{ 2, 7 }, { 3, 2 }, { 6, 3 }, { 11, 2 }},
741 3.0f,
742 {{ 2.000000f, 7.000000f }, { 2.500000f, 4.500000f }, { 3.500000f, 3.500000f },
743 { 5.000000f, 3.000000f },
744 { 6.500000f, 2.500000f }, { 8.500000f, 2.500000f }, { 11.000000f, 2.000000f }}
745 );
746 testChopMonoCubicAtY(reporter, "curve, negative slope @ 2.5",
747 {{ 2, 7 }, { 3, 2 }, { 6, 3 }, { 11, 2 }},
748 2.5f,
749 {{ 2.000000f, 7.000000f }, { 2.750000f, 3.250000f }, { 4.625000f, 2.875000f },
750 { 7.625000f, 2.500000f },
751 { 8.625000f, 2.375000f }, { 9.750000f, 2.250000f }, { 11.000000f, 2.000000f }}
752 );
753
754 // This is the same curve as above, just the 4 points given in the opposite order.
755 // We would expect the math to result in the same chop points, with the outputs
756 // in the opposite order too.
757 testChopMonoCubicAtY(reporter, "inverted curve, negative slope @ 5.0",
758 {{ 11, 2 }, { 6, 3 }, { 3, 2 }, { 2, 7 }},
759 5.0f,
760 {{ 11.000000f, 2.000000f }, { 6.814281f, 2.837144f }, { 4.030182f, 2.272668f },
761 { 2.647702f, 5.000000f },
762 { 2.378757f, 5.530570f }, { 2.162856f, 6.185719f }, { 2.000000f, 7.000000f }}
763 );
764 testChopMonoCubicAtY(reporter, "inverted curve, negative slope @ 3.0",
765 {{ 11, 2 }, { 6, 3 }, { 3, 2 }, { 2, 7 }},
766 3.0f,
767 {{ 11.000000f, 2.000000f }, { 8.500000f, 2.500000f }, { 6.500000f, 2.500000f },
768 { 5.000000f, 3.000000f },
769 { 3.500000f, 3.500000f }, { 2.500000f, 4.500000f }, { 2.000000f, 7.000000f }}
770 );
771 testChopMonoCubicAtY(reporter, "inverted curve, negative slope @ 2.5",
772 {{ 11, 2 }, { 6, 3 }, { 3, 2 }, { 2, 7 }},
773 2.5f,
774 {{ 11.000000f, 2.000000f }, { 9.750000f, 2.250000f }, { 8.625000f, 2.375000f },
775 { 7.625000f, 2.500000f },
776 { 4.625000f, 2.875000f }, { 2.750000f, 3.250000f }, { 2.000000f, 7.000000f }}
777 );
778
779 testChopMonoCubicAtY(reporter, "big curve, negative slope @ 90",
780 {{ -2, 100 }, { 0, 0 }, { 0, 0 }, { 100, -2 }},
781 90.f,
782 {{ -2.000000f,100.000000f }, { -1.930979f, 96.548965f }, { -1.864341f, 93.217033f },
783 { -1.795892f, 90.000000f },
784 { 0.119096f, -0.002382f }, { 3.451032f, -0.069021f }, {100.000000f, -2.000000f }}
785 );
786 testChopMonoCubicAtY(reporter, "big curve, negative slope @ 10",
787 {{ -2, 100 }, { 0, 0 }, { 0, 0 }, { 100, -2 }},
788 10.f,
789 {{ -2.000000f,100.000000f }, { -0.937505f, 46.875271f }, { -0.439458f, 21.972910f },
790 { 14.787060f, 10.000000f },
791 { 28.222368f, -0.564447f }, { 53.124729f, -1.062495f }, {100.000000f, -2.000000f }}
792 );
793 testChopMonoCubicAtY(reporter, "big curve, negative slope @ 0",
794 {{ -2, 100 }, { 0, 0 }, { 0, 0 }, { 100, -2 }},
795 0.f,
796 {{ -2.000000f,100.000000f }, { -0.426983f, 21.349131f }, { -0.091157f, 4.557854f },
797 { 48.633648f, 0.000000f },
798 { 61.859592f, -1.237192f }, { 78.650871f, -1.573017f }, {100.000000f, -2.000000f }}
799 );
800
801 testChopMonoCubicAtY(reporter, "ossfuzz:55680 curve barely crosses Y axis",
802 {{-250.121582f, -1180.09509f}, {10.007843f, -1180.09509f},
803 {20.015685f, -786.041259f}, {40.0313721f, 2.0664072f}},
804 0.f,
805 {{-250.121582f, -1180.095093f}, {9.780392f, -1180.095093f}, {19.997992f, -786.730042f},
806 {39.978889f, 0.000000f},
807 {39.996376f, 0.688501f}, {40.013870f, 1.377304f}, {40.031372f, 2.066407f}}
808 );
809 }
810
DEF_TEST(GeometryChopMonoCubicAtY_OutOfRangeReturnFalse,reporter)811 DEF_TEST(GeometryChopMonoCubicAtY_OutOfRangeReturnFalse, reporter) {
812 SkPoint inputs[] = {{ 0, 0 }, { 0, 0 }, { 10, 10 }, { 10, 10 }};
813 SkPoint outputs[7];
814
815 // Too low
816 REPORTER_ASSERT(reporter, !SkChopMonoCubicAtY(inputs, -10, outputs));
817 // Too high
818 REPORTER_ASSERT(reporter, !SkChopMonoCubicAtY(inputs, 20, outputs));
819 }
820
testChopMonoCubicAtX(skiatest::Reporter * reporter,std::string name,SkSpan<const SkPoint> curveInputs,SkScalar xToChopAt,SkSpan<const SkPoint> expectedOutputs)821 static void testChopMonoCubicAtX(skiatest::Reporter* reporter, std::string name,
822 SkSpan<const SkPoint> curveInputs, SkScalar xToChopAt,
823 SkSpan<const SkPoint> expectedOutputs) {
824 skiatest::ReporterContext subtest(reporter, name);
825 REPORTER_ASSERT(reporter, curveInputs.size() == 4,
826 "Invalid test case. Input curve should have 4 points");
827 REPORTER_ASSERT(reporter, expectedOutputs.size() == 7,
828 "Invalid test case. Outputs should have 7 points");
829 REPORTER_ASSERT(reporter, SkScalarNearlyEqual(expectedOutputs[3].x(), xToChopAt),
830 "Invalid test case. 4th point's X should be %f", xToChopAt);
831
832 SkPoint outputs[7];
833 // Make sure it actually chopped
834 REPORTER_ASSERT(reporter, SkChopMonoCubicAtX(curveInputs.begin(), xToChopAt, outputs));
835
836 for (int i = 0; i < 7; ++i) {
837 REPORTER_ASSERT(reporter, nearly_equal(expectedOutputs[i], outputs[i]),
838 "(%f, %f) != (%f, %f) at index %d",
839 expectedOutputs[i].x(), expectedOutputs[i].y(),
840 outputs[i].x(), outputs[i].y(), i);
841 }
842 }
843
DEF_TEST(GeometryChopMonoCubicAtX_Successful,reporter)844 DEF_TEST(GeometryChopMonoCubicAtX_Successful, reporter) {
845 // These cubics are all arbitrary, picked using Desmos for something that looked "nice".
846
847 testChopMonoCubicAtX(reporter, "straight, positive slope @ 2.5",
848 {{ 0, 0 }, { 0, 0 }, { 10, 10 }, { 10, 10 }},
849 2.5f,
850 {{ 0.000000f, 0.000000f }, { 0.000000f, 0.000000f }, { 1.065055f, 1.065055f },
851 { 2.500000f, 2.500000f },
852 { 5.461981f, 5.461981f }, { 10.000000f, 10.000000f }, { 10.000000f, 10.000000f }}
853 );
854 testChopMonoCubicAtX(reporter, "straight, positive slope @ 5.0",
855 {{ 0, 0 }, { 0, 0 }, { 10, 10 }, { 10, 10 }},
856 5.0f,
857 {{ 0.000000f, 0.000000f }, { 0.000000f, 0.000000f }, { 2.500000f, 2.500000f },
858 { 5.000000f, 5.000000f },
859 { 7.500000f, 7.500000f }, { 10.000000f, 10.000000f }, { 10.000000f, 10.000000f }}
860 );
861 testChopMonoCubicAtX(reporter, "straight, positive slope @ 9.0",
862 {{ 0, 0 }, { 0, 0 }, { 10, 10 }, { 10, 10 }},
863 9.0f,
864 {{ 0.000000f, 0.000000f }, { 0.000000f, 0.000000f }, { 6.467375f, 6.467375f },
865 { 9.000000f, 9.000000f },
866 { 9.616623f, 9.616623f }, { 10.000000f, 10.000000f }, { 10.000000f, 10.000000f }}
867 );
868 testChopMonoCubicAtX(reporter, "straight, positive slope @ 10.0",
869 {{ 0, 0 }, { 0, 0 }, { 10, 10 }, { 10, 10 }},
870 10.0f,
871 {{ 0.000000f, 0.000000f }, { 0.000000f, 0.000000f }, { 10.000000f, 10.000000f },
872 { 10.000000f, 10.000000f },
873 { 10.000000f, 10.000000f }, { 10.000000f, 10.000000f }, { 10.000000f, 10.000000f }}
874 );
875
876 testChopMonoCubicAtX(reporter, "curve, positive slope @ 2.0",
877 {{ 1, 1 }, { 5, 2 }, { 7, 4 }, { 8, 7 }},
878 2.0f,
879 {{ 1.000000f, 1.000000f }, { 1.348275f, 1.087069f }, { 1.681389f, 1.181719f },
880 { 2.000000f, 1.283949f },
881 { 5.340694f, 2.355856f }, { 7.087069f, 4.261207f }, { 8.000000f, 7.000000f }}
882 );
883 testChopMonoCubicAtX(reporter, "curve, positive slope @ 5.0",
884 {{ 1, 1 }, { 5, 2 }, { 7, 4 }, { 8, 7 }},
885 5.0f,
886 {{ 1.000000f, 1.000000f }, { 2.650396f, 1.412599f }, { 3.960316f, 1.995436f },
887 { 5.000000f, 2.748511f },
888 { 6.480158f, 3.820634f }, { 7.412599f, 5.237797f }, { 8.000000f, 7.000000f }}
889 );
890
891 testChopMonoCubicAtX(reporter, "curve, negative slope @ 5.0",
892 {{ 2, 7 }, { 3, 2 }, { 6, 3 }, { 11, 2 }},
893 5.0f,
894 {{ 2.000000f, 7.000000f }, { 2.500000f, 4.500000f }, { 3.500000f, 3.500000f },
895 { 5.000000f, 3.000000f },
896 { 6.500000f, 2.500000f }, { 8.500000f, 2.500000f }, { 11.000000f, 2.000000f }}
897 );
898 testChopMonoCubicAtX(reporter, "curve, negative slope @ 3.0",
899 {{ 2, 7 }, { 3, 2 }, { 6, 3 }, { 11, 2 }},
900 3.0f,
901 {{ 2.000000f, 7.000000f }, { 2.228714f, 5.856432f }, { 2.562047f, 5.026724f },
902 { 3.000000f, 4.415163f },
903 { 4.476901f, 2.352807f }, { 7.143568f, 2.771286f }, { 11.000000f, 2.000000f }}
904 );
905 testChopMonoCubicAtX(reporter, "curve, negative slope @ 2.5",
906 {{ 2, 7 }, { 3, 2 }, { 6, 3 }, { 11, 2 }},
907 2.5f,
908 {{ 2.000000f, 7.000000f }, { 2.131881f, 6.340593f }, { 2.298548f, 5.785543f },
909 { 2.500000f, 5.316498f },
910 { 3.826073f, 2.228977f }, { 6.659407f, 2.868119f }, { 11.000000f, 2.000000f }}
911 );
912
913 // This is the same curve as above, just the 4 points given in the opposite order.
914 // We would expect the math to result in the same chop points, with the outputs
915 // in the opposite order too.
916 testChopMonoCubicAtX(reporter, "inverted curve, negative slope @ 5.0",
917 {{ 11, 2 }, { 6, 3 }, { 3, 2 }, { 2, 7 }},
918 5.0f,
919 {{ 11.000000f, 2.000000f }, { 8.500000f, 2.500000f }, { 6.500000f, 2.500000f },
920 { 5.000000f, 3.000000f },
921 { 3.500000f, 3.500000f }, { 2.500000f, 4.500000f }, { 2.000000f, 7.000000f }}
922 );
923 testChopMonoCubicAtX(reporter, "inverted curve, negative slope @ 3.0",
924 {{ 11, 2 }, { 6, 3 }, { 3, 2 }, { 2, 7 }},
925 3.0f,
926 {{ 11.000000f, 2.000000f }, { 7.143568f, 2.771286f }, { 4.476901f, 2.352807f },
927 { 3.000000f, 4.415163f },
928 { 2.562047f, 5.026724f }, { 2.228714f, 5.856432f }, { 2.000000f, 7.000000f }}
929 );
930 testChopMonoCubicAtX(reporter, "inverted curve, negative slope @ 2.5",
931 {{ 11, 2 }, { 6, 3 }, { 3, 2 }, { 2, 7 }},
932 2.5f,
933 {{ 11.000000f, 2.000000f }, { 6.659407f, 2.868119f }, { 3.826073f, 2.228977f },
934 { 2.500000f, 5.316498f },
935 { 2.298548f, 5.785543f }, { 2.131881f, 6.340593f }, { 2.000000f, 7.000000f }}
936 );
937
938 testChopMonoCubicAtX(reporter, "big curve, negative slope @ 90",
939 {{ -2, 100 }, { 0, 0 }, { 0, 0 }, { 100, -2 }},
940 90.f,
941 {{ -2.000000f,100.000000f }, { -0.069021f, 3.451032f }, { -0.002382f, 0.119096f },
942 { 90.000000f, -1.795892f },
943 { 93.217033f, -1.864341f }, { 96.548965f, -1.930979f }, {100.000000f, -2.000000f }}
944 );
945 testChopMonoCubicAtX(reporter, "big curve, negative slope @ 10",
946 {{ -2, 100 }, { 0, 0 }, { 0, 0 }, { 100, -2 }},
947 10.f,
948 {{ -2.000000f,100.000000f }, { -1.062495f, 53.124729f }, { -0.564447f, 28.222368f },
949 { 10.000000f, 14.787060f },
950 { 21.972910f, -0.439458f }, { 46.875271f, -0.937505f }, {100.000000f, -2.000000f }}
951 );
952 testChopMonoCubicAtX(reporter, "big curve, negative slope @ 0",
953 {{ -2, 100 }, { 0, 0 }, { 0, 0 }, { 100, -2 }},
954 0.f,
955 {{ -2.000000f,100.000000f }, { -1.573017f, 78.650871f }, { -1.237192f, 61.859592f },
956 { 0.000000f, 48.633648f },
957 { 4.557854f, -0.091157f }, { 21.349131f, -0.426983f }, {100.000000f, -2.000000f }}
958 );
959 }
960
DEF_TEST(GeometryChopMonoCubicAtX_OutOfRangeReturnFalse,reporter)961 DEF_TEST(GeometryChopMonoCubicAtX_OutOfRangeReturnFalse, reporter) {
962 SkPoint inputs[] = {{ 0, 0 }, { 0, 0 }, { 10, 10 }, { 10, 10 }};
963 SkPoint outputs[7];
964
965 // Too low
966 REPORTER_ASSERT(reporter, !SkChopMonoCubicAtX(inputs, -10, outputs));
967 // Too high
968 REPORTER_ASSERT(reporter, !SkChopMonoCubicAtX(inputs, 20, outputs));
969 }
970