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])) {
SkDebugf("not equal %g %g\n", (float)a[i], (float)b[i]);
return false;
}
}
return true;
}
static bool nearly_equal(const SkMatrix44& a, const SkMatrix44& b) {
for (int i = 0; i < 4; ++i) {
for (int j = 0; j < 4; ++j) {
if (!nearly_equal_scalar(a.get(i, j), b.get(i, j))) {
printf("not equal %g %g\n", a.get(i, j), b.get(i, j));
return false;
}
}
}
return true;
}
static void test_3x3_conversion(skiatest::Reporter* reporter) {
SkMScalar values4x4[16] = { 1, 2, 3, 4,
5, 6, 7, 8,
9, 10, 11, 12,
13, 14, 15, 16
};
SkScalar values3x3[9] = { 1, 2, 4,
5, 6, 8,
13, 14, 16
};
SkMScalar values4x4flattened[16] = { 1, 2, 0, 4,
5, 6, 0, 8,
0, 0, 1, 0,
13, 14, 0, 16
};
SkMatrix44 a44(SkMatrix44::kUninitialized_Constructor);
a44.setRowMajor(values4x4);
SkMatrix a33 = a44;
SkMatrix expected33;
for (int i = 0; i < 9; i++) expected33[i] = values3x3[i];
REPORTER_ASSERT(reporter, expected33 == a33);
SkMatrix44 a44flattened = a33;
SkMatrix44 expected44flattened(SkMatrix44::kUninitialized_Constructor);
expected44flattened.setRowMajor(values4x4flattened);
REPORTER_ASSERT(reporter, nearly_equal(a44flattened, expected44flattened));
// Test that a point with a Z value of 0 is transformed the same way.
SkScalar vec4[4] = { 2, 4, 0, 8 };
SkScalar vec3[3] = { 2, 4, 8 };
SkScalar vec4transformed[4];
SkScalar vec3transformed[3];
SkScalar vec4transformed2[4];
a44.mapScalars(vec4, vec4transformed);
a33.mapHomogeneousPoints(vec3transformed, vec3, 1);
a44flattened.mapScalars(vec4, vec4transformed2);
REPORTER_ASSERT(reporter, nearly_equal_scalar(vec4transformed[0], vec3transformed[0]));
REPORTER_ASSERT(reporter, nearly_equal_scalar(vec4transformed[1], vec3transformed[1]));
REPORTER_ASSERT(reporter, nearly_equal_scalar(vec4transformed[3], vec3transformed[2]));
REPORTER_ASSERT(reporter, nearly_equal_scalar(vec4transformed[0], vec4transformed2[0]));
REPORTER_ASSERT(reporter, nearly_equal_scalar(vec4transformed[1], vec4transformed2[1]));
REPORTER_ASSERT(reporter, !nearly_equal_scalar(vec4transformed[2], vec4transformed2[2]));
REPORTER_ASSERT(reporter, nearly_equal_scalar(vec4transformed[3], vec4transformed2[3]));
}