gecko/gfx/skia/include/core/SkScalarCompare.h
2013-04-02 16:49:07 -04:00

39 lines
1.2 KiB
C

/*
* Copyright 2006 The Android Open Source Project
*
* Use of this source code is governed by a BSD-style license that can be
* found in the LICENSE file.
*/
#ifndef SkScalarCompare_DEFINED
#define SkScalarCompare_DEFINED
#include "SkFloatBits.h"
#include "SkRect.h"
/** Skia can spend a lot of time just comparing scalars (e.g. quickReject).
When scalar==fixed, this is very fast, and when scalar==hardware-float, this
is also reasonable, but if scalar==software-float, then each compare can be
a function call and take real time. To account for that, we have the flag
SK_SCALAR_SLOW_COMPARES.
If this is defined, we have a special trick where we quickly convert floats
to a 2's compliment form, and then treat them as signed 32bit integers. In
this form we lose a few subtlties (e.g. NaNs always comparing false) but
we gain the speed of integer compares.
*/
#ifdef SK_SCALAR_SLOW_COMPARES
typedef int32_t SkScalarCompareType;
typedef SkIRect SkRectCompareType;
#define SkScalarToCompareType(x) SkScalarAs2sCompliment(x)
#else
typedef SkScalar SkScalarCompareType;
typedef SkRect SkRectCompareType;
#define SkScalarToCompareType(x) (x)
#endif
#endif