skia2/third_party/skcms/skcms_internal.h

/*
 * Copyright 2018 Google Inc.
 *
 * Use of this source code is governed by a BSD-style license that can be
 * found in the LICENSE file.
 */

#pragma once

// skcms_internal.h contains APIs shared by skcms' internals and its test tools.
// Please don't use this header from outside the skcms repo.

#include "skcms.h"
#include <stdbool.h>
#include <stdint.h>

#ifdef __cplusplus
extern "C" {
#endif

// ~~~~ General Helper Macros ~~~~
    #define ARRAY_COUNT(arr) (int)(sizeof((arr)) / sizeof(*(arr)))

    typedef struct skcms_ICCTag {
        uint32_t       signature;
        uint32_t       type;
        uint32_t       size;
        const uint8_t* buf;
    } skcms_ICCTag;

    void skcms_GetTagByIndex    (const skcms_ICCProfile*, uint32_t idx, skcms_ICCTag*);
    bool skcms_GetTagBySignature(const skcms_ICCProfile*, uint32_t sig, skcms_ICCTag*);

    float skcms_MaxRoundtripError(const skcms_Curve* curve, const skcms_TransferFunction* inv_tf);

    // 252 of a random shuffle of all possible bytes.
    // 252 is evenly divisible by 3 and 4.  Only 192, 10, 241, and 43 are missing.
    // Used for ICC profile equivalence testing.
    extern const uint8_t skcms_252_random_bytes[252];

// ~~~~ Portable Math ~~~~
    static inline float floorf_(float x) {
        float roundtrip = (float)((int)x);
        return roundtrip > x ? roundtrip - 1 : roundtrip;
    }
    static inline float fabsf_(float x) { return x < 0 ? -x : x; }
    float powf_(float, float);

// ~~~~ Does this pixel format need a palette pointer to be usable? ~~~~
    static inline bool needs_palette(skcms_PixelFormat fmt) {
        return (fmt >> 1) == (skcms_PixelFormat_RGBA_8888_Palette8 >> 1);
    }

#ifdef __cplusplus
}
#endif