add fFx1 field, returning where to start the iterator for fCount1 range
add unittest
git-svn-id: http://skia.googlecode.com/svn/trunk@1145 2bbb7eff-a529-9590-31e7-b0007b416f81
diff --git a/tests/ClampRangeTest.cpp b/tests/ClampRangeTest.cpp
new file mode 100644
index 0000000..b3d1e78
--- /dev/null
+++ b/tests/ClampRangeTest.cpp
@@ -0,0 +1,86 @@
+#include "Test.h"
+#include "SkClampRange.h"
+#include "SkRandom.h"
+
+static skiatest::Reporter* gReporter;
+
+static int classify_value(SkFixed fx, int v0, int v1) {
+ if (fx <= 0) {
+ return v0;
+ }
+ if (fx >= 0xFFFF) {
+ return v1;
+ }
+ REPORTER_ASSERT(gReporter, false);
+ return 0;
+}
+
+#define V0 -42
+#define V1 1024
+
+static void slow_check(const SkClampRange& range,
+ SkFixed fx, SkFixed dx, int count) {
+ SkASSERT(range.fCount0 + range.fCount1 + range.fCount2 == count);
+
+ int i;
+ for (i = 0; i < range.fCount0; i++) {
+ int v = classify_value(fx, V0, V1);
+ REPORTER_ASSERT(gReporter, v == range.fV0);
+ fx += dx;
+ }
+ REPORTER_ASSERT(gReporter, range.fCount1 == 0 || fx == range.fFx1);
+ for (i = 0; i < range.fCount1; i++) {
+ REPORTER_ASSERT(gReporter, fx >= 0 && fx <= 0xFFFF);
+ fx += dx;
+ }
+ for (i = 0; i < range.fCount2; i++) {
+ int v = classify_value(fx, V0, V1);
+ REPORTER_ASSERT(gReporter, v == range.fV1);
+ fx += dx;
+ }
+}
+
+static void test_range(SkFixed fx, SkFixed dx, int count) {
+ SkClampRange range;
+ range.init(fx, dx, count, V0, V1);
+ slow_check(range, fx, dx, count);
+}
+
+#define ff(x) SkIntToFixed(x)
+
+static void TestClampRange(skiatest::Reporter* reporter) {
+ gReporter = reporter;
+
+ test_range(0, 0, 20);
+ test_range(0xFFFF, 0, 20);
+ test_range(-ff(2), 0, 20);
+ test_range( ff(2), 0, 20);
+
+ test_range(-10, 1, 20);
+ test_range(10, -1, 20);
+ test_range(-10, 3, 20);
+ test_range(10, -3, 20);
+
+ SkRandom rand;
+
+ // test non-overflow cases
+ for (int i = 0; i < 1000000; i++) {
+ SkFixed fx = rand.nextS() >> 1;
+ SkFixed sx = rand.nextS() >> 1;
+ int count = rand.nextU() % 1000 + 1;
+ SkFixed dx = (sx - fx) / count;
+ test_range(fx, dx, count);
+ }
+
+ // test overflow cases
+ for (int i = 0; i < 0*1000000; i++) {
+ SkFixed fx = rand.nextS();
+ SkFixed sx = rand.nextS();
+ int count = rand.nextU() % 1000 + 1;
+ SkFixed dx = (sx - fx) / count;
+ test_range(fx, dx, count);
+ }
+}
+
+#include "TestClassDef.h"
+DEFINE_TESTCLASS("ClampRange", ClampRangeClass, TestClampRange)