1#include "Test.h"
2#include "SkColor.h"
3#include "SkUnPreMultiply.h"
4
5static void test_premul(skiatest::Reporter* reporter) {
6    for (int a = 0; a <= 255; a++) {
7        for (int x = 0; x <= 255; x++) {
8            SkColor c0 = SkColorSetARGB(a, x, x, x);
9            SkPMColor p0 = SkPreMultiplyColor(c0);
10
11            SkColor c1 = SkUnPreMultiply::PMColorToColor(p0);
12            SkPMColor p1 = SkPreMultiplyColor(c1);
13
14            // we can't promise that c0 == c1, since c0 -> p0 is a many to one
15            // function, however, we can promise that p0 -> c1 -> p1 : p0 == p1
16            REPORTER_ASSERT(reporter, p0 == p1);
17
18            {
19                int ax = SkMulDiv255Ceiling(x, a);
20                REPORTER_ASSERT(reporter, ax <= a);
21            }
22        }
23    }
24}
25
26
27static void TestColor(skiatest::Reporter* reporter) {
28    test_premul(reporter);
29}
30
31#include "TestClassDef.h"
32DEFINE_TESTCLASS("Color", ColorTestClass, TestColor)
33