add initial unittest framework (tests)

move some previous unittests out of core classes and into tests



git-svn-id: http://skia.googlecode.com/svn/trunk@96 2bbb7eff-a529-9590-31e7-b0007b416f81

1 files changed, 400 insertions, 0 deletions

diff --git a/tests/MathTest.cpp b/tests/MathTest.cpp
new file mode 100644
index 0000000000..a759ab19a1
--- /dev/null
+++ b/tests/MathTest.cpp
@@ -0,0 +1,400 @@
+#include "Test.h"
+#include "SkPoint.h"
+#include "SkRandom.h"
+
+#if defined(SkLONGLONG)
+static int symmetric_fixmul(int a, int b) {
+    int sa = SkExtractSign(a);
+    int sb = SkExtractSign(b);
+    
+    a = SkApplySign(a, sa);
+    b = SkApplySign(b, sb);
+    
+#if 1
+    int c = (int)(((SkLONGLONG)a * b) >> 16);
+    
+    return SkApplySign(c, sa ^ sb);
+#else
+    SkLONGLONG ab = (SkLONGLONG)a * b;
+    if (sa ^ sb) {
+        ab = -ab;
+    }
+    return ab >> 16;
+#endif
+}
+#endif
+
+static void check_length(skiatest::Reporter* reporter,
+                         const SkPoint& p, SkScalar targetLen) {
+#ifdef SK_CAN_USE_FLOAT
+    float x = SkScalarToFloat(p.fX);
+    float y = SkScalarToFloat(p.fY);
+    float len = sk_float_sqrt(x*x + y*y);
+    
+    len /= SkScalarToFloat(targetLen);
+    
+    REPORTER_ASSERT(reporter, len > 0.999f && len < 1.001f);
+#endif
+}
+
+#if defined(SK_CAN_USE_FLOAT)
+
+static float nextFloat(SkRandom& rand) {
+    SkFloatIntUnion data;
+    data.fSignBitInt = rand.nextU();
+    return data.fFloat;
+}
+
+/*  returns true if a == b as resulting from (int)x. Since it is undefined
+ what to do if the float exceeds 2^32-1, we check for that explicitly.
+ */
+static bool equal_float_native_skia(float x, uint32_t ni, uint32_t si) {
+    if (!(x == x)) {    // NAN
+        return si == SK_MaxS32 || si == SK_MinS32;
+    }
+    // for out of range, C is undefined, but skia always should return NaN32
+    if (x > SK_MaxS32) {
+        return si == SK_MaxS32;
+    }
+    if (x < -SK_MaxS32) {
+        return si == SK_MinS32;
+    }
+    return si == ni;
+}
+
+static void assert_float_equal(skiatest::Reporter* reporter, const char op[],
+                               float x, uint32_t ni, uint32_t si) {
+    if (!equal_float_native_skia(x, ni, si)) {
+        SkString desc;
+        desc.printf("%s float %g bits %x native %x skia %x\n", op, x, ni, si);
+        reporter->reportFailed(desc);
+    }
+}
+
+static void test_float_cast(skiatest::Reporter* reporter, float x) {
+    int ix = (int)x;
+    int iix = SkFloatToIntCast(x);
+    assert_float_equal(reporter, "cast", x, ix, iix);
+}
+
+static void test_float_floor(skiatest::Reporter* reporter, float x) {
+    int ix = (int)floor(x);
+    int iix = SkFloatToIntFloor(x);
+    assert_float_equal(reporter, "floor", x, ix, iix);
+}
+
+static void test_float_round(skiatest::Reporter* reporter, float x) {
+    double xx = x + 0.5;    // need intermediate double to avoid temp loss
+    int ix = (int)floor(xx);
+    int iix = SkFloatToIntRound(x);
+    assert_float_equal(reporter, "round", x, ix, iix);
+}
+
+static void test_float_ceil(skiatest::Reporter* reporter, float x) {
+    int ix = (int)ceil(x);
+    int iix = SkFloatToIntCeil(x);
+    assert_float_equal(reporter, "ceil", x, ix, iix);
+}
+
+static void test_float_conversions(skiatest::Reporter* reporter, float x) {
+    test_float_cast(reporter, x);
+    test_float_floor(reporter, x);
+    test_float_round(reporter, x);
+    test_float_ceil(reporter, x);
+}
+
+static void test_int2float(skiatest::Reporter* reporter, int ival) {
+    float x0 = (float)ival;
+    float x1 = SkIntToFloatCast(ival);
+    float x2 = SkIntToFloatCast_NoOverflowCheck(ival);
+    REPORTER_ASSERT(reporter, x0 == x1);
+    REPORTER_ASSERT(reporter, x0 == x2);
+}
+
+static void unittest_fastfloat(skiatest::Reporter* reporter) {
+    SkRandom rand;
+    size_t i;
+    
+    static const float gFloats[] = {
+        0.f, 1.f, 0.5f, 0.499999f, 0.5000001f, 1.f/3,
+        0.000000001f, 1000000000.f,     // doesn't overflow
+        0.0000000001f, 10000000000.f    // does overflow
+    };
+    for (i = 0; i < SK_ARRAY_COUNT(gFloats); i++) {
+        //        SkDebugf("---- test floats %g %d\n", gFloats[i], (int)gFloats[i]);
+        test_float_conversions(reporter, gFloats[i]);
+        test_float_conversions(reporter, -gFloats[i]);
+    }
+    
+    for (int outer = 0; outer < 100; outer++) {
+        rand.setSeed(outer);
+        for (i = 0; i < 100000; i++) {
+            float x = nextFloat(rand);
+            test_float_conversions(reporter, x);
+        }
+        
+        test_int2float(reporter, 0);
+        test_int2float(reporter, 1);
+        test_int2float(reporter, -1);
+        for (i = 0; i < 100000; i++) {
+            // for now only test ints that are 24bits or less, since we don't
+            // round (down) large ints the same as IEEE...
+            int ival = rand.nextU() & 0xFFFFFF;
+            test_int2float(reporter, ival);
+            test_int2float(reporter, -ival);
+        }
+    }
+}
+
+#endif
+
+static void test_muldiv255(skiatest::Reporter* reporter) {
+#ifdef SK_CAN_USE_FLOAT
+    for (int a = 0; a <= 255; a++) {
+        for (int b = 0; b <= 255; b++) {
+            int ab = a * b;
+            float s = ab / 255.0f;
+            int round = (int)floorf(s + 0.5f);
+            int trunc = (int)floorf(s);
+            
+            int iround = SkMulDiv255Round(a, b);
+            int itrunc = SkMulDiv255Trunc(a, b);
+            
+            REPORTER_ASSERT(reporter, iround == round);
+            REPORTER_ASSERT(reporter, itrunc == trunc);
+            
+            REPORTER_ASSERT(reporter, itrunc <= iround);
+            REPORTER_ASSERT(reporter, iround <= a);
+            REPORTER_ASSERT(reporter, iround <= b);
+        }
+    }
+#endif
+}
+
+static void TestMath(skiatest::Reporter* reporter) {    
+    int         i;
+    int32_t     x;
+    SkRandom    rand;
+    
+    // these should not assert
+    SkToS8(127);    SkToS8(-128);       SkToU8(255);
+    SkToS16(32767); SkToS16(-32768);    SkToU16(65535);
+    SkToS32(2*1024*1024);   SkToS32(-2*1024*1024);  SkToU32(4*1024*1024);
+    
+    // these should assert
+#if 0
+    SkToS8(128);
+    SkToS8(-129);
+    SkToU8(256);
+    SkToU8(-5);
+    
+    SkToS16(32768);
+    SkToS16(-32769);
+    SkToU16(65536);
+    SkToU16(-5);
+    
+    if (sizeof(size_t) > 4) {
+        SkToS32(4*1024*1024);
+        SkToS32(-4*1024*1024);
+        SkToU32(5*1024*1024);
+        SkToU32(-5);
+    }
+#endif
+    
+    test_muldiv255(reporter);
+    
+    {
+        SkScalar x = SK_ScalarNaN;
+        REPORTER_ASSERT(reporter, SkScalarIsNaN(x));
+    }
+    
+    for (i = 1; i <= 10; i++) {
+        x = SkCubeRootBits(i*i*i, 11);
+        REPORTER_ASSERT(reporter, x == i);
+    }
+    
+    REPORTER_ASSERT(reporter, !"test the reporter");
+    
+    x = SkFixedSqrt(SK_Fixed1);
+    REPORTER_ASSERT(reporter, x == SK_Fixed1);
+    x = SkFixedSqrt(SK_Fixed1/4);
+    REPORTER_ASSERT(reporter, x == SK_Fixed1/2);
+    x = SkFixedSqrt(SK_Fixed1*4);
+    REPORTER_ASSERT(reporter, x == SK_Fixed1*2);
+    
+    x = SkFractSqrt(SK_Fract1);
+    REPORTER_ASSERT(reporter, x == SK_Fract1);
+    x = SkFractSqrt(SK_Fract1/4);
+    REPORTER_ASSERT(reporter, x == SK_Fract1/2);
+    x = SkFractSqrt(SK_Fract1/16);
+    REPORTER_ASSERT(reporter, x == SK_Fract1/4);
+    
+    for (i = 1; i < 100; i++) {
+        x = SkFixedSqrt(SK_Fixed1 * i * i);
+        REPORTER_ASSERT(reporter, x == SK_Fixed1 * i);
+    }
+    
+    for (i = 0; i < 1000; i++) {
+        int value = rand.nextS16();
+        int max = rand.nextU16();
+        
+        int clamp = SkClampMax(value, max);
+        int clamp2 = value < 0 ? 0 : (value > max ? max : value);
+        REPORTER_ASSERT(reporter, clamp == clamp2);
+    }
+    
+    for (i = 0; i < 100000; i++) {
+        SkPoint p;
+        
+        p.setLength(rand.nextS(), rand.nextS(), SK_Scalar1);
+        check_length(reporter, p, SK_Scalar1);
+        p.setLength(rand.nextS() >> 13, rand.nextS() >> 13, SK_Scalar1);
+        check_length(reporter, p, SK_Scalar1);
+    }
+    
+    {
+        SkFixed result = SkFixedDiv(100, 100);
+        REPORTER_ASSERT(reporter, result == SK_Fixed1);
+        result = SkFixedDiv(1, SK_Fixed1);
+        REPORTER_ASSERT(reporter, result == 1);
+    }
+    
+#ifdef SK_CAN_USE_FLOAT
+    unittest_fastfloat(reporter);
+#endif
+    
+#ifdef SkLONGLONG
+    for (i = 0; i < 100000; i++) {
+        SkFixed numer = rand.nextS();
+        SkFixed denom = rand.nextS();
+        SkFixed result = SkFixedDiv(numer, denom);
+        SkLONGLONG check = ((SkLONGLONG)numer << 16) / denom;
+        
+        (void)SkCLZ(numer);
+        (void)SkCLZ(denom);
+        
+        REPORTER_ASSERT(reporter, result != (SkFixed)SK_NaN32);
+        if (check > SK_MaxS32) {
+            check = SK_MaxS32;
+        } else if (check < -SK_MaxS32) {
+            check = SK_MinS32;
+        }
+        REPORTER_ASSERT(reporter, result == (int32_t)check);
+        
+        result = SkFractDiv(numer, denom);
+        check = ((SkLONGLONG)numer << 30) / denom;
+        
+        REPORTER_ASSERT(reporter, result != (SkFixed)SK_NaN32);
+        if (check > SK_MaxS32) {
+            check = SK_MaxS32;
+        } else if (check < -SK_MaxS32) {
+            check = SK_MinS32;
+        }
+        REPORTER_ASSERT(reporter, result == (int32_t)check);
+        
+        // make them <= 2^24, so we don't overflow in fixmul
+        numer = numer << 8 >> 8;
+        denom = denom << 8 >> 8;
+        
+        result = SkFixedMul(numer, denom);
+        SkFixed r2 = symmetric_fixmul(numer, denom);
+        //        SkASSERT(result == r2);
+        
+        result = SkFixedMul(numer, numer);
+        r2 = SkFixedSquare(numer);
+        REPORTER_ASSERT(reporter, result == r2);
+        
+#ifdef SK_CAN_USE_FLOAT
+        if (numer >= 0 && denom >= 0) {
+            SkFixed mean = SkFixedMean(numer, denom);
+            float fm = sk_float_sqrt(sk_float_abs(SkFixedToFloat(numer) * SkFixedToFloat(denom)));
+            SkFixed mean2 = SkFloatToFixed(fm);
+            int diff = SkAbs32(mean - mean2);
+            REPORTER_ASSERT(reporter, diff <= 1);
+        }
+        
+        {
+            SkFixed mod = SkFixedMod(numer, denom);
+            float n = SkFixedToFloat(numer);
+            float d = SkFixedToFloat(denom);
+            float m = sk_float_mod(n, d);
+            REPORTER_ASSERT(reporter, mod == 0 || (mod < 0) == (m < 0)); // ensure the same sign
+            int diff = SkAbs32(mod - SkFloatToFixed(m));
+            REPORTER_ASSERT(reporter, (diff >> 7) == 0);
+        }
+#endif
+    }
+#endif
+    
+#ifdef SK_CAN_USE_FLOAT
+    for (i = 0; i < 100000; i++) {
+        SkFract x = rand.nextU() >> 1;
+        double xx = (double)x / SK_Fract1;
+        SkFract xr = SkFractSqrt(x);
+        SkFract check = SkFloatToFract(sqrt(xx));
+        REPORTER_ASSERT(reporter, xr == check || xr == check-1 || xr == check+1);
+        
+        xr = SkFixedSqrt(x);
+        xx = (double)x / SK_Fixed1;
+        check = SkFloatToFixed(sqrt(xx));
+        REPORTER_ASSERT(reporter, xr == check || xr == check-1);
+        
+        xr = SkSqrt32(x);
+        xx = (double)x;
+        check = (int32_t)sqrt(xx);
+        REPORTER_ASSERT(reporter, xr == check || xr == check-1);
+    }
+#endif
+    
+#if !defined(SK_SCALAR_IS_FLOAT) && defined(SK_CAN_USE_FLOAT)
+    {
+        SkFixed s, c;
+        s = SkFixedSinCos(0, &c);
+        REPORTER_ASSERT(reporter, s == 0);
+        REPORTER_ASSERT(reporter, c == SK_Fixed1);
+    }
+    
+    int maxDiff = 0;
+    for (i = 0; i < 10000; i++) {
+        SkFixed rads = rand.nextS() >> 10;
+        double frads = SkFixedToFloat(rads);
+        
+        SkFixed s, c;
+        s = SkScalarSinCos(rads, &c);
+        
+        double fs = sin(frads);
+        double fc = cos(frads);
+        
+        SkFixed is = SkFloatToFixed(fs);
+        SkFixed ic = SkFloatToFixed(fc);
+        
+        maxDiff = SkMax32(maxDiff, SkAbs32(is - s));
+        maxDiff = SkMax32(maxDiff, SkAbs32(ic - c));
+    }
+    SkDebugf("SinCos: maximum error = %d\n", maxDiff);
+#endif
+}
+
+///////////////////////////////////////////////////////////////////////////////
+
+namespace skiatest {
+
+    class MathTest : public Test {
+    public:
+        static Test* Factory(void*) {
+            return SkNEW(MathTest);
+        }
+
+    protected:
+        virtual void onGetName(SkString* name) {
+            name->set("Math");
+        }
+        
+        virtual void onRun(Reporter* reporter) {
+            TestMath(reporter);
+        }
+    };
+
+    static TestRegistry gReg(MathTest::Factory);
+}
+