/*
* 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 "Test.h"
#include "SkMath.h"
#include "SkMatrix.h"
#include "SkRandom.h"
static bool nearly_equal_scalar(SkScalar a, SkScalar b) {
// Note that we get more compounded error for multiple operations when
// SK_SCALAR_IS_FIXED.
#ifdef SK_SCALAR_IS_FLOAT
const SkScalar tolerance = SK_Scalar1 / 200000;
#else
const SkScalar tolerance = SK_Scalar1 / 1024;
#endif
return SkScalarAbs(a - b) <= tolerance;
}
static bool nearly_equal(const SkMatrix& a, const SkMatrix& b) {
for (int i = 0; i < 9; i++) {
if (!nearly_equal_scalar(a[i], b[i])) {
printf("not equal %g %g\n", (float)a[i], (float)b[i]);
return false;
}
}
return true;
}
static bool is_identity(const SkMatrix& m) {
SkMatrix identity;
identity.reset();
return nearly_equal(m, identity);
}
static void test_flatten(skiatest::Reporter* reporter, const SkMatrix& m) {
// add 100 in case we have a bug, I don't want to kill my stack in the test
char buffer[SkMatrix::kMaxFlattenSize + 100];
uint32_t size1 = m.flatten(NULL);
uint32_t size2 = m.flatten(buffer);
REPORTER_ASSERT(reporter, size1 == size2);
REPORTER_ASSERT(reporter, size1 <= SkMatrix::kMaxFlattenSize);
SkMatrix m2;
uint32_t size3 = m2.unflatten(buffer);
REPORTER_ASSERT(reporter, size1 == size2);
REPORTER_ASSERT(reporter, m == m2);
char buffer2[SkMatrix::kMaxFlattenSize + 100];
size3 = m2.flatten(buffer2);
REPORTER_ASSERT(reporter, size1 == size2);
REPORTER_ASSERT(reporter, memcmp(buffer, buffer2, size1) == 0);
}
void test_matrix_max_stretch(skiatest::Reporter* reporter) {
SkMatrix identity;
identity.reset();
REPORTER_ASSERT(reporter, SK_Scalar1 == identity.getMaxStretch());
SkMatrix scale;
scale.setScale(SK_Scalar1 * 2, SK_Scalar1 * 4);
REPORTER_ASSERT(reporter, SK_Scalar1 * 4 == scale.getMaxStretch());
SkMatrix rot90Scale;
rot90Scale.setRotate(90 * SK_Scalar1);
rot90Scale.postScale(SK_Scalar1 / 4, SK_Scalar1 / 2);
REPORTER_ASSERT(reporter, SK_Scalar1 / 2 == rot90Scale.getMaxStretch());
SkMatrix rotate;
rotate.setRotate(128 * SK_Scalar1);
REPORTER_ASSERT(reporter, SkScalarAbs(SK_Scalar1 - rotate.getMaxStretch()) <= SK_ScalarNearlyZero);
SkMatrix translate;
translate.setTranslate(10 * SK_Scalar1, -5 * SK_Scalar1);
REPORTER_ASSERT(reporter, SK_Scalar1 == translate.getMaxStretch());
SkMatrix perspX;
perspX.reset();
perspX.setPerspX(SkScalarToPersp(SK_Scalar1 / 1000));
REPORTER_ASSERT(reporter, -SK_Scalar1 == perspX.getMaxStretch());
SkMatrix perspY;
perspY.reset();
perspY.setPerspX(SkScalarToPersp(-SK_Scalar1 / 500));
REPORTER_ASSERT(reporter, -SK_Scalar1 == perspY.getMaxStretch());
SkMatrix baseMats[] = {scale, rot90Scale, rotate,
translate, perspX, perspY};
SkMatrix mats[2*SK_ARRAY_COUNT(baseMats)];
for (size_t i = 0; i < SK_ARRAY_COUNT(baseMats); ++i) {
mats[i] = baseMats[i];
bool invertable = mats[i].invert(&mats[i + SK_ARRAY_COUNT(baseMats)]);
REPORTER_ASSERT(reporter, invertable);
}
SkRandom rand;
for (int m = 0; m < 1000; ++m) {
SkMatrix mat;
mat.reset();
for (int i = 0; i < 4; ++i) {
int x = rand.nextU() % SK_ARRAY_COUNT(mats);
mat.postConcat(mats[x]);
}
SkScalar stretch = mat.getMaxStretch();
if ((stretch < 0) != mat.hasPerspective()) {
stretch = mat.getMaxStretch();
}
REPORTER_ASSERT(reporter, (stretch < 0) == mat.hasPerspective());
if (mat.hasPerspective()) {
m -= 1; // try another non-persp matrix
continue;
}
// test a bunch of vectors. None should be scaled by more than stretch
// (modulo some error) and we should find a vector that is scaled by
// almost stretch.
static const SkScalar gStretchTol = (105 * SK_Scalar1) / 100;
static const SkScalar gMaxStretchTol = (97 * SK_Scalar1) / 100;
SkScalar max = 0;
SkVector vectors[1000];
for (size_t i = 0; i < SK_ARRAY_COUNT(vectors); ++i) {
vectors[i].fX = rand.nextSScalar1();
vectors[i].fY = rand.nextSScalar1();
if (!vectors[i].normalize()) {
i -= 1;
continue;
}
}
mat.mapVectors(vectors, SK_ARRAY_COUNT(vectors));
for (size_t i = 0; i < SK_ARRAY_COUNT(vectors); ++i) {
SkScalar d = vectors[i].length();
REPORTER_ASSERT(reporter, SkScalarDiv(d, stretch) < gStretchTol);
if (max < d) {
max = d;
}
}
REPORTER_ASSERT(reporter, SkScalarDiv(max, stretch) >= gMaxStretchTol);
}
}
void TestMatrix(skiatest::Reporter* reporter) {
SkMatrix mat, inverse, iden1, iden2;
mat.reset();
mat.setTranslate(SK_Scalar1, SK_Scalar1);
mat.invert(&inverse);
iden1.setConcat(mat, inverse);
REPORTER_ASSERT(reporter, is_identity(iden1));
mat.setScale(SkIntToScalar(2), SkIntToScalar(2));
mat.invert(&inverse);
iden1.setConcat(mat, inverse);
REPORTER_ASSERT(reporter, is_identity(iden1));
test_flatten(reporter, mat);
mat.setScale(SK_Scalar1/2, SK_Scalar1/2);
mat.invert(&inverse);
iden1.setConcat(mat, inverse);
REPORTER_ASSERT(reporter, is_identity(iden1));
test_flatten(reporter, mat);
mat.setScale(SkIntToScalar(3), SkIntToScalar(5), SkIntToScalar(20), 0);
mat.postRotate(SkIntToScalar(25));
REPORTER_ASSERT(reporter, mat.invert(NULL));
mat.invert(&inverse);
iden1.setConcat(mat, inverse);
REPORTER_ASSERT(reporter, is_identity(iden1));
iden2.setConcat(inverse, mat);
REPORTER_ASSERT(reporter, is_identity(iden2));
test_flatten(reporter, mat);
test_flatten(reporter, iden2);
// rectStaysRect test
{
static const struct {
SkScalar m00, m01, m10, m11;
bool mStaysRect;
}
gRectStaysRectSamples[] = {
{ 0, 0, 0, 0, false },
{ 0, 0, 0, SK_Scalar1, false },
{ 0, 0, SK_Scalar1, 0, false },
{ 0, 0, SK_Scalar1, SK_Scalar1, false },
{ 0, SK_Scalar1, 0, 0, false },
{ 0, SK_Scalar1, 0, SK_Scalar1, false },
{ 0, SK_Scalar1, SK_Scalar1, 0, true },
{ 0, SK_Scalar1, SK_Scalar1, SK_Scalar1, false },
{ SK_Scalar1, 0, 0, 0, false },
{ SK_Scalar1, 0, 0, SK_Scalar1, true },
{ SK_Scalar1, 0, SK_Scalar1, 0, false },
{ SK_Scalar1, 0, SK_Scalar1, SK_Scalar1, false },
{ SK_Scalar1, SK_Scalar1, 0, 0, false },
{ SK_Scalar1, SK_Scalar1, 0, SK_Scalar1, false },
{ SK_Scalar1, SK_Scalar1, SK_Scalar1, 0, false },
{ SK_Scalar1, SK_Scalar1, SK_Scalar1, SK_Scalar1, false }
};
for (size_t i = 0; i < SK_ARRAY_COUNT(gRectStaysRectSamples); i++) {
SkMatrix m;
m.reset();
m.set(SkMatrix::kMScaleX, gRectStaysRectSamples[i].m00);
m.set(SkMatrix::kMSkewX, gRectStaysRectSamples[i].m01);
m.set(SkMatrix::kMSkewY, gRectStaysRectSamples[i].m10);
m.set(SkMatrix::kMScaleY, gRectStaysRectSamples[i].m11);
REPORTER_ASSERT(reporter,
m.rectStaysRect() == gRectStaysRectSamples[i].mStaysRect);
}
}
mat.reset();
mat.set(SkMatrix::kMScaleX, SkIntToScalar(1));
mat.set(SkMatrix::kMSkewX, SkIntToScalar(2));
mat.set(SkMatrix::kMTransX, SkIntToScalar(3));
mat.set(SkMatrix::kMSkewY, SkIntToScalar(4));
mat.set(SkMatrix::kMScaleY, SkIntToScalar(5));
mat.set(SkMatrix::kMTransY, SkIntToScalar(6));
SkScalar affine[6];
REPORTER_ASSERT(reporter, mat.asAffine(affine));
#define affineEqual(e) affine[SkMatrix::kA##e] == mat.get(SkMatrix::kM##e)
REPORTER_ASSERT(reporter, affineEqual(ScaleX));
REPORTER_ASSERT(reporter, affineEqual(SkewY));
REPORTER_ASSERT(reporter, affineEqual(SkewX));
REPORTER_ASSERT(reporter, affineEqual(ScaleY));
REPORTER_ASSERT(reporter, affineEqual(TransX));
REPORTER_ASSERT(reporter, affineEqual(TransY));
#undef affineEqual
mat.set(SkMatrix::kMPersp1, SkScalarToPersp(SK_Scalar1 / 2));
REPORTER_ASSERT(reporter, !mat.asAffine(affine));
test_matrix_max_stretch(reporter);
}
#include "TestClassDef.h"
DEFINE_TESTCLASS("Matrix", MatrixTestClass, TestMatrix)