skia/config/SkUserConfig.h

/*
 * Copyright (C) 2006 The Android Open Source Project
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

#ifndef SkUserConfig_DEFINED
#define SkUserConfig_DEFINED
#pragma once

/*  SkTypes.h, the root of the public header files, does the following trick:
 
    #include <SkPreConfig.h>
    #include <SkUserConfig.h>
    #include <SkPostConfig.h>
 
    SkPreConfig.h runs first, and it is responsible for initializing certain
    skia defines.
 
    SkPostConfig.h runs last, and its job is to just check that the final
    defines are consistent (i.e. that we don't have mutually conflicting
    defines).
 
    SkUserConfig.h (this file) runs in the middle. It gets to change or augment
    the list of flags initially set in preconfig, and then postconfig checks
    that everything still makes sense.

    Below are optional defines that add, subtract, or change default behavior
    in Skia. Your port can locally edit this file to enable/disable flags as
    you choose, or these can be delared on your command line (i.e. -Dfoo).

    By default, this include file will always default to having all of the flags
    commented out, so including it will have no effect.
*/

///////////////////////////////////////////////////////////////////////////////

/*  Scalars (the fractional value type in skia) can be implemented either as
    floats or 16.16 integers (fixed). Exactly one of these two symbols must be
    defined.
*/
//#define SK_SCALAR_IS_FLOAT
//#define SK_SCALAR_IS_FIXED


/*  Somewhat independent of how SkScalar is implemented, Skia also wants to know
    if it can use floats at all. Naturally, if SK_SCALAR_IS_FLOAT is defined,
    then so muse SK_CAN_USE_FLOAT, but if scalars are fixed, SK_CAN_USE_FLOAT
    can go either way.
 */
//#define SK_CAN_USE_FLOAT

/*  Temporarily turn on SK_USE_FLOATBITS so critical float->int conversions in Skia
    are done with saturation.
    TODO(wjmaclean@chromium.org): Remove this once saturating float->int implemented
    throughout Skia.
 */
#define SK_USE_FLOATBITS

/*  For some performance-critical scalar operations, skia will optionally work
    around the standard float operators if it knows that the CPU does not have
    native support for floats. If your environment uses software floating point,
    define this flag.
 */
//#define SK_SOFTWARE_FLOAT


/*  Skia has lots of debug-only code. Often this is just null checks or other
    parameter checking, but sometimes it can be quite intrusive (e.g. check that
    each 32bit pixel is in premultiplied form). This code can be very useful
    during development, but will slow things down in a shipping product.
 
    By default, these mutually exclusive flags are defined in SkPreConfig.h,
    based on the presence or absence of NDEBUG, but that decision can be changed
    here.
 */
//#define SK_DEBUG
//#define SK_RELEASE


/*  If, in debugging mode, Skia needs to stop (presumably to invoke a debugger)
    it will call SK_CRASH(). If this is not defined it, it is defined in
    SkPostConfig.h to write to an illegal address
 */
//#define SK_CRASH() *(int *)(uintptr_t)0 = 0


/*  preconfig will have attempted to determine the endianness of the system,
    but you can change these mutually exclusive flags here.
 */
//#define SK_CPU_BENDIAN
//#define SK_CPU_LENDIAN


/*  Some compilers don't support long long for 64bit integers. If yours does
    not, define this to the appropriate type.
 */
//#define SkLONGLONG int64_t


/*  Some envorinments do not suport writable globals (eek!). If yours does not,
    define this flag.
 */
//#define SK_USE_RUNTIME_GLOBALS

/*  If zlib is available and you want to support the flate compression
    algorithm (used in PDF generation), define SK_ZLIB_INCLUDE to be the
    include path.
 */
//#define SK_ZLIB_INCLUDE <zlib.h>
#if defined(USE_SYSTEM_ZLIB)
#define SK_ZLIB_INCLUDE <zlib.h>
#else
#define SK_ZLIB_INCLUDE "third_party/zlib/zlib.h"
#endif

/*  Define this to allow PDF scalars above 32k.  The PDF/A spec doesn't allow
    them, but modern PDF interpreters should handle them just fine.
 */
//#define SK_ALLOW_LARGE_PDF_SCALARS

/*  Define this to provide font subsetter for font subsetting when generating
    PDF documents.
 */
#define SK_SFNTLY_SUBSETTER "third_party/sfntly/src/subsetter/font_subsetter.h"

/*  Define this to remove dimension checks on bitmaps. Not all blits will be
    correct yet, so this is mostly for debugging the implementation.
 */
//#define SK_ALLOW_OVER_32K_BITMAPS


/*  To write debug messages to a console, skia will call SkDebugf(...) following
    printf conventions (e.g. const char* format, ...). If you want to redirect
    this to something other than printf, define yours here
 */
//#define SkDebugf(...)  MyFunction(__VA_ARGS__)


/*  If SK_DEBUG is defined, then you can optionally define SK_SUPPORT_UNITTEST
    which will run additional self-tests at startup. These can take a long time,
    so this flag is optional.
 */
#ifdef SK_DEBUG
#define SK_SUPPORT_UNITTEST
#endif

/* If this is not defined, skia dithers gradients. Turning this on will make
   gradients look better, but might have a performance impact. When it's turned
   on, several webkit pixel tests will need to be rebaselined, too.
   http://crbug.com/41756
 */
#define SK_DISABLE_DITHER_32BIT_GRADIENT

// ===== Begin Chrome-specific definitions =====

#define SK_SCALAR_IS_FLOAT
#undef SK_SCALAR_IS_FIXED

#define GR_MAX_OFFSCREEN_AA_DIM     512

// Log the file and line number for assertions.
#define SkDebugf(...) SkDebugf_FileLine(__FILE__, __LINE__, false, __VA_ARGS__)
SK_API void SkDebugf_FileLine(const char* file, int line, bool fatal,
                              const char* format, ...);

// Marking the debug print as "fatal" will cause a debug break, so we don't need
// a separate crash call here.
#define SK_DEBUGBREAK(cond) do { if (!(cond)) { \
    SkDebugf_FileLine(__FILE__, __LINE__, true, \
    "%s:%d: failed assertion \"%s\"\n", \
    __FILE__, __LINE__, #cond); } } while (false)

// All little-endian Chrome platforms agree:  BGRA is the optimal pixel layout.
#define SK_A32_SHIFT    24
#define SK_R32_SHIFT    16
#define SK_G32_SHIFT    8
#define SK_B32_SHIFT    0

#if defined(SK_BUILD_FOR_WIN32)

#define SK_BUILD_FOR_WIN

// VC8 doesn't support stdint.h, so we define those types here.
#define SK_IGNORE_STDINT_DOT_H
typedef signed char int8_t;
typedef unsigned char uint8_t;
typedef short int16_t;
typedef unsigned short uint16_t;
typedef int int32_t;
typedef unsigned uint32_t;

// VC doesn't support __restrict__, so make it a NOP.
#undef SK_RESTRICT
#define SK_RESTRICT

// Skia uses this deprecated bzero function to fill zeros into a string.
#define bzero(str, len) memset(str, 0, len)

#elif defined(SK_BUILD_FOR_MAC)

#define SK_CPU_LENDIAN
#undef  SK_CPU_BENDIAN

#elif defined(SK_BUILD_FOR_UNIX)

// Prefer FreeType's emboldening algorithm to Skia's (which does a hairline
// outline and doesn't look very good).
#define SK_USE_FREETYPE_EMBOLDEN

#ifdef SK_CPU_BENDIAN
// Above we set the order for ARGB channels in registers. I suspect that, on
// big endian machines, you can keep this the same and everything will work.
// The in-memory order will be different, of course, but as long as everything
// is reading memory as words rather than bytes, it will all work. However, if
// you find that colours are messed up I thought that I would leave a helpful
// locator for you. Also see the comments in
// base/gfx/bitmap_platform_device_linux.h
#error Read the comment at this location
#endif

#endif

// The default crash macro writes to badbeef which can cause some strange
// problems. Instead, pipe this through to the logging function as a fatal
// assertion.
#define SK_CRASH() SkDebugf_FileLine(__FILE__, __LINE__, true, "SK_CRASH")

// ===== End Chrome-specific definitions =====

#endif