///////////////////////////////////////////////////////////////////////////////
-bool SkMatrix44::invert(SkMatrix44* inverse) const {
+static bool is_matrix_finite(const SkMatrix44& matrix) {
+ SkMScalar accumulator = 0;
+ for (int row = 0; row < 4; ++row) {
+ for (int col = 0; col < 4; ++col) {
+ accumulator *= matrix.get(row, col);
+ }
+ }
+ return accumulator == 0;
+}
+
+bool SkMatrix44::invert(SkMatrix44* storage) const {
if (this->isIdentity()) {
- if (inverse) {
- inverse->setIdentity();
+ if (storage) {
+ storage->setIdentity();
}
return true;
}
if (this->isTranslate()) {
- if (inverse) {
- inverse->setTranslate(-fMat[3][0], -fMat[3][1], -fMat[3][2]);
+ if (storage) {
+ storage->setTranslate(-fMat[3][0], -fMat[3][1], -fMat[3][2]);
}
return true;
}
+ SkMatrix44 tmp(kUninitialized_Constructor);
+ // Use storage if it's available and distinct from this matrix.
+ SkMatrix44* inverse = (storage && storage != this) ? storage : &tmp;
if (this->isScaleTranslate()) {
if (0 == fMat[0][0] * fMat[1][1] * fMat[2][2]) {
return false;
}
- if (inverse) {
- double invXScale = 1 / fMat[0][0];
- double invYScale = 1 / fMat[1][1];
- double invZScale = 1 / fMat[2][2];
+ double invXScale = 1 / fMat[0][0];
+ double invYScale = 1 / fMat[1][1];
+ double invZScale = 1 / fMat[2][2];
- inverse->fMat[0][0] = SkDoubleToMScalar(invXScale);
- inverse->fMat[0][1] = 0;
- inverse->fMat[0][2] = 0;
- inverse->fMat[0][3] = 0;
+ inverse->fMat[0][0] = SkDoubleToMScalar(invXScale);
+ inverse->fMat[0][1] = 0;
+ inverse->fMat[0][2] = 0;
+ inverse->fMat[0][3] = 0;
- inverse->fMat[1][0] = 0;
- inverse->fMat[1][1] = SkDoubleToMScalar(invYScale);
- inverse->fMat[1][2] = 0;
- inverse->fMat[1][3] = 0;
+ inverse->fMat[1][0] = 0;
+ inverse->fMat[1][1] = SkDoubleToMScalar(invYScale);
+ inverse->fMat[1][2] = 0;
+ inverse->fMat[1][3] = 0;
- inverse->fMat[2][0] = 0;
- inverse->fMat[2][1] = 0;
- inverse->fMat[2][2] = SkDoubleToMScalar(invZScale);
- inverse->fMat[2][3] = 0;
+ inverse->fMat[2][0] = 0;
+ inverse->fMat[2][1] = 0;
+ inverse->fMat[2][2] = SkDoubleToMScalar(invZScale);
+ inverse->fMat[2][3] = 0;
- inverse->fMat[3][0] = SkDoubleToMScalar(-fMat[3][0] * invXScale);
- inverse->fMat[3][1] = SkDoubleToMScalar(-fMat[3][1] * invYScale);
- inverse->fMat[3][2] = SkDoubleToMScalar(-fMat[3][2] * invZScale);
- inverse->fMat[3][3] = 1;
+ inverse->fMat[3][0] = SkDoubleToMScalar(-fMat[3][0] * invXScale);
+ inverse->fMat[3][1] = SkDoubleToMScalar(-fMat[3][1] * invYScale);
+ inverse->fMat[3][2] = SkDoubleToMScalar(-fMat[3][2] * invZScale);
+ inverse->fMat[3][3] = 1;
- inverse->setTypeMask(this->getType());
- }
+ inverse->setTypeMask(this->getType());
+ if (!is_matrix_finite(*inverse)) {
+ return false;
+ }
+ if (storage && inverse != storage) {
+ *storage = *inverse;
+ }
return true;
}
if (!sk_float_isfinite(invdet)) {
return false;
}
- if (NULL == inverse) {
- return true;
- }
b00 *= invdet;
b01 *= invdet;
inverse->fMat[3][3] = 1;
inverse->setTypeMask(this->getType());
+ if (!is_matrix_finite(*inverse)) {
+ return false;
+ }
+ if (storage && inverse != storage) {
+ *storage = *inverse;
+ }
return true;
}
if (!sk_float_isfinite(invdet)) {
return false;
}
- if (NULL == inverse) {
- return true;
- }
b00 *= invdet;
b01 *= invdet;
inverse->fMat[3][3] = SkDoubleToMScalar(a20 * b03 - a21 * b01 + a22 * b00);
inverse->dirtyTypeMask();
+ inverse->setTypeMask(this->getType());
+ if (!is_matrix_finite(*inverse)) {
+ return false;
+ }
+ if (storage && inverse != storage) {
+ *storage = *inverse;
+ }
return true;
}
0, 0, -1, 1};
expected.setRowMajord(expectedInverseAffineAndPerspective);
REPORTER_ASSERT(reporter, nearly_equal(expected, inverse));
+
+ SkMatrix44 tinyScale(SkMatrix44::kIdentity_Constructor);
+ tinyScale.setDouble(0, 0, 1e-39);
+ REPORTER_ASSERT(reporter, tinyScale.getType() == SkMatrix44::kScale_Mask);
+ REPORTER_ASSERT(reporter, !tinyScale.invert(NULL));
+ REPORTER_ASSERT(reporter, !tinyScale.invert(&inverse));
+
+ SkMatrix44 tinyScaleTranslate(SkMatrix44::kIdentity_Constructor);
+ tinyScaleTranslate.setDouble(0, 0, 1e-38);
+ REPORTER_ASSERT(reporter, tinyScaleTranslate.invert(NULL));
+ tinyScaleTranslate.setDouble(0, 3, 10);
+ REPORTER_ASSERT(
+ reporter, tinyScaleTranslate.getType() ==
+ (SkMatrix44::kScale_Mask | SkMatrix44::kTranslate_Mask));
+ REPORTER_ASSERT(reporter, !tinyScaleTranslate.invert(NULL));
+ REPORTER_ASSERT(reporter, !tinyScaleTranslate.invert(&inverse));
+
+ SkMatrix44 tinyScalePerspective(SkMatrix44::kIdentity_Constructor);
+ tinyScalePerspective.setDouble(0, 0, 1e-39);
+ tinyScalePerspective.setDouble(3, 2, -1);
+ REPORTER_ASSERT(reporter, (tinyScalePerspective.getType() &
+ SkMatrix44::kPerspective_Mask) ==
+ SkMatrix44::kPerspective_Mask);
+ REPORTER_ASSERT(reporter, !tinyScalePerspective.invert(NULL));
+ REPORTER_ASSERT(reporter, !tinyScalePerspective.invert(&inverse));
}
static void test_transpose(skiatest::Reporter* reporter) {