Add skia to the repository.

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@16 0039d316-1c4b-4281-b951-d872f2087c98

1 files changed, 43 insertions, 0 deletions

diff --git a/skia/corecg/SkFloatBits.h b/skia/corecg/SkFloatBits.h
new file mode 100644
index 0000000..012770a
--- /dev/null
+++ b/skia/corecg/SkFloatBits.h
@@ -0,0 +1,43 @@
+#ifndef SkFloatBits_DEFINED
+#define SkFloatBits_DEFINED
+
+#include "SkTypes.h"
+
+/** Convert a sign-bit int (i.e. float interpreted as int) into a 2s compliement
+    int. This also converts -0 (0x80000000) to 0. Doing this to a float allows
+    it to be compared using normal C operators (<, <=, etc.)
+*/
+static inline int32_t SkSignBitTo2sCompliment(int32_t x) {
+    if (x < 0) {
+        x &= 0x7FFFFFFF;
+        x = -x;
+    }
+    return x;
+}
+
+#ifdef SK_CAN_USE_FLOAT
+
+union SkFloatIntUnion {
+    float   fFloat;
+    int32_t fSignBitInt;
+};
+
+/** Return the float as a 2s compliment int. Just just be used to compare floats
+    to each other or against positive float-bit-constants (like 0)
+*/
+static int32_t SkFloatAsInt(float x) {
+    SkFloatIntUnion data;
+    data.fFloat = x;
+    return SkSignBitTo2sCompliment(data.fSignBitInt);
+}
+
+#endif
+
+#ifdef SK_SCALAR_IS_FLOAT
+    #define SkScalarAsInt(x)    SkFloatAsInt(x)
+#else
+    #define SkScalarAsInt(x)    (x)
+#endif
+
+#endif
+