add unittest for IntersectLine, used by hairlines

git-svn-id: http://skia.googlecode.com/svn/trunk@447 2bbb7eff-a529-9590-31e7-b0007b416f81

1 files changed, 89 insertions, 0 deletions

diff --git a/tests/ClipperTest.cpp b/tests/ClipperTest.cpp
new file mode 100644
index 0000000000..66301fcfdf
--- /dev/null
+++ b/tests/ClipperTest.cpp
@@ -0,0 +1,89 @@
+#include "Test.h"
+#include "SkPath.h"
+#include "SkLineClipper.h"
+#include "SkEdgeClipper.h"
+
+static void test_intersectline(skiatest::Reporter* reporter) {
+    static const SkScalar L = 0;
+    static const SkScalar T = 0;
+    static const SkScalar R = SkIntToScalar(100);
+    static const SkScalar B = SkIntToScalar(100);
+    static const SkScalar CX = SkScalarHalf(L + R);
+    static const SkScalar CY = SkScalarHalf(T + B);
+    static const SkRect gR = { L, T, R, B };
+
+    size_t i;
+    SkPoint dst[2];
+
+    static const SkPoint gEmpty[] = {
+        // sides
+        { L, CY }, { L - 10, CY },
+        { R, CY }, { R + 10, CY },
+        { CX, T }, { CX, T - 10 },
+        { CX, B }, { CX, B + 10 },
+        // corners
+        { L, T }, { L - 10, T - 10 },
+        { L, B }, { L - 10, B + 10 },
+        { R, T }, { R + 10, T - 10 },
+        { R, B }, { R + 10, B + 10 },
+    };
+    for (i = 0; i < SK_ARRAY_COUNT(gEmpty); i += 2) {
+        bool valid = SkLineClipper::IntersectLine(&gEmpty[i], gR, dst);
+        if (valid) {
+            SkDebugf("----- [%d] %g %g -> %g %g\n", i/2, dst[0].fX, dst[0].fY, dst[1].fX, dst[1].fY);
+        }
+        REPORTER_ASSERT(reporter, !valid);
+    }
+    
+    static const SkPoint gFull[] = {
+        // diagonals, chords
+        { L, T }, { R, B },
+        { L, B }, { R, T },
+        { CX, T }, { CX, B },
+        { L, CY }, { R, CY },
+        { CX, T }, { R, CY },
+        { CX, T }, { L, CY },
+        { L, CY }, { CX, B },
+        { R, CY }, { CX, B },
+        // edges
+        { L, T }, { L, B },
+        { R, T }, { R, B },
+        { L, T }, { R, T },
+        { L, B }, { R, B },
+    };
+    for (i = 0; i < SK_ARRAY_COUNT(gFull); i += 2) {
+        bool valid = SkLineClipper::IntersectLine(&gFull[i], gR, dst);
+        if (!valid || memcmp(&gFull[i], dst, sizeof(dst))) {
+            SkDebugf("++++ [%d] %g %g -> %g %g\n", i/2, dst[0].fX, dst[0].fY, dst[1].fX, dst[1].fY);
+        }
+        REPORTER_ASSERT(reporter, valid && !memcmp(&gFull[i], dst, sizeof(dst)));
+    }
+    
+    static const SkPoint gPartial[] = {
+        { L - 10, CY }, { CX, CY }, { L, CY }, { CX, CY },
+        { CX, T - 10 }, { CX, CY }, { CX, T }, { CX, CY },
+        { R + 10, CY }, { CX, CY }, { R, CY }, { CX, CY },
+        { CX, B + 10 }, { CX, CY }, { CX, B }, { CX, CY },
+        // extended edges
+        { L, T - 10 }, { L, B + 10 }, { L, T }, { L, B },
+        { R, T - 10 }, { R, B + 10 }, { R, T }, { R, B },
+        { L - 10, T }, { R + 10, T }, { L, T }, { R, T },
+        { L - 10, B }, { R + 10, B }, { L, B }, { R, B },
+    };
+    for (i = 0; i < SK_ARRAY_COUNT(gPartial); i += 4) {
+        bool valid = SkLineClipper::IntersectLine(&gPartial[i], gR, dst);
+        if (!valid || memcmp(&gPartial[i+2], dst, sizeof(dst))) {
+            SkDebugf("++++ [%d] %g %g -> %g %g\n", i/2, dst[0].fX, dst[0].fY, dst[1].fX, dst[1].fY);
+        }
+        REPORTER_ASSERT(reporter, valid &&
+                                  !memcmp(&gPartial[i+2], dst, sizeof(dst)));
+    }
+    
+}
+
+void TestClipper(skiatest::Reporter* reporter) {
+    test_intersectline(reporter);
+}
+
+#include "TestClassDef.h"
+DEFINE_TESTCLASS("Clipper", TestClipperClass, TestClipper)