1
2/*
3 * Copyright 2006 The Android Open Source Project
4 *
5 * Use of this source code is governed by a BSD-style license that can be
6 * found in the LICENSE file.
7 */
8
9
10#ifndef SkScalarCompare_DEFINED
11#define SkScalarCompare_DEFINED
12
13#include "SkFloatBits.h"
14#include "SkRect.h"
15
16/** Skia can spend a lot of time just comparing scalars (e.g. quickReject).
17    When scalar==fixed, this is very fast, and when scalar==hardware-float, this
18    is also reasonable, but if scalar==software-float, then each compare can be
19    a function call and take real time. To account for that, we have the flag
20    SK_SCALAR_SLOW_COMPARES.
21
22    If this is defined, we have a special trick where we quickly convert floats
23    to a 2's compliment form, and then treat them as signed 32bit integers. In
24    this form we lose a few subtlties (e.g. NaNs always comparing false) but
25    we gain the speed of integer compares.
26 */
27
28#ifdef SK_SCALAR_SLOW_COMPARES
29    typedef int32_t SkScalarCompareType;
30    typedef SkIRect SkRectCompareType;
31    #define SkScalarToCompareType(x)    SkScalarAs2sCompliment(x)
32#else
33    typedef SkScalar SkScalarCompareType;
34    typedef SkRect SkRectCompareType;
35    #define SkScalarToCompareType(x)    (x)
36#endif
37
38#endif
39
40