ispc-texcomp 0.1.20

////////////////////////////////////////////////////////////////////////////////
// Copyright (c) 2016-2019, Intel Corporation
//
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// of this software and associated documentation files (the "Software"), to
// deal in the Software without restriction, including without limitation the
// rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
// sell copies of the Software, and to permit persons to whom the Software is
// furnished to do so, subject to the following conditions:
//
// The above copyright notice and this permission notice shall be included in
// all copies or substantial portions of the Software.
//
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
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// IN THE SOFTWARE.
////////////////////////////////////////////////////////////////////////////////

#include <stdint.h>

struct rgba_surface
{
    uint8_t* ptr;
    int32_t width;
    int32_t height;
    int32_t stride; // in bytes
};

struct bc7_enc_settings
{
    bool mode_selection[4];
    int refineIterations[8];

    bool skip_mode2;
    int fastSkipTreshold_mode1;
    int fastSkipTreshold_mode3;
    int fastSkipTreshold_mode7;

    int mode45_channel0;
    int refineIterations_channel;

    int channels;
};

struct bc6h_enc_settings
{
    bool slow_mode;
    bool fast_mode;
    int refineIterations_1p;
    int refineIterations_2p;
    int fastSkipTreshold;
};

struct etc_enc_settings
{
    int fastSkipTreshold;
};

struct astc_enc_settings
{
    int block_width;
    int block_height;
    int channels;

    int fastSkipTreshold;
    int refineIterations;
};

// profiles for RGB data (alpha channel will be ignored)
extern "C" void GetProfile_ultrafast(bc7_enc_settings* settings);
extern "C" void GetProfile_veryfast(bc7_enc_settings* settings);
extern "C" void GetProfile_fast(bc7_enc_settings* settings);
extern "C" void GetProfile_basic(bc7_enc_settings* settings);
extern "C" void GetProfile_slow(bc7_enc_settings* settings);

// profiles for RGBA inputs
extern "C" void GetProfile_alpha_ultrafast(bc7_enc_settings* settings);
extern "C" void GetProfile_alpha_veryfast(bc7_enc_settings* settings);
extern "C" void GetProfile_alpha_fast(bc7_enc_settings* settings);
extern "C" void GetProfile_alpha_basic(bc7_enc_settings* settings);
extern "C" void GetProfile_alpha_slow(bc7_enc_settings* settings);

// profiles for BC6H (RGB HDR)
extern "C" void GetProfile_bc6h_veryfast(bc6h_enc_settings* settings);
extern "C" void GetProfile_bc6h_fast(bc6h_enc_settings* settings);
extern "C" void GetProfile_bc6h_basic(bc6h_enc_settings* settings);
extern "C" void GetProfile_bc6h_slow(bc6h_enc_settings* settings);
extern "C" void GetProfile_bc6h_veryslow(bc6h_enc_settings* settings);

// profiles for ETC
extern "C" void GetProfile_etc_slow(etc_enc_settings* settings);

// profiles for ASTC
extern "C" void GetProfile_astc_fast(astc_enc_settings* settings, int block_width, int block_height);
extern "C" void GetProfile_astc_alpha_fast(astc_enc_settings* settings, int block_width, int block_height);
extern "C" void GetProfile_astc_alpha_slow(astc_enc_settings* settings, int block_width, int block_height);

// helper function to replicate border pixels for the desired block sizes (bpp = 32 or 64)
extern "C" void ReplicateBorders(rgba_surface* dst_slice, const rgba_surface* src_tex, int x, int y, int bpp);

/*
Notes:
    - input width and height need to be a multiple of block size
    - LDR input is 32 bit/pixel (sRGB), HDR is 64 bit/pixel (half float)
        - for BC4 input is 8bit/pixel (R8), for BC5 input is 16bit/pixel (RG8)
    - dst buffer must be allocated with enough space for the compressed texture:
        - 8 bytes/block for BC1/BC4/ETC1,
        - 16 bytes/block for BC3/BC5/BC6H/BC7/ASTC
    - the blocks are stored in raster scan order (natural CPU texture layout)
    - use the GetProfile_* functions to select various speed/quality tradeoffs
    - the RGB profiles are slightly faster as they ignore the alpha channel
*/

extern "C" void CompressBlocksBC1(const rgba_surface* src, uint8_t* dst);
extern "C" void CompressBlocksBC3(const rgba_surface* src, uint8_t* dst);
extern "C" void CompressBlocksBC4(const rgba_surface* src, uint8_t* dst);
extern "C" void CompressBlocksBC5(const rgba_surface* src, uint8_t* dst);
extern "C" void CompressBlocksBC6H(const rgba_surface* src, uint8_t* dst, bc6h_enc_settings* settings);
extern "C" void CompressBlocksBC7(const rgba_surface* src, uint8_t* dst, bc7_enc_settings* settings);
extern "C" void CompressBlocksETC1(const rgba_surface* src, uint8_t* dst, etc_enc_settings* settings);
extern "C" void CompressBlocksASTC(const rgba_surface* src, uint8_t* dst, astc_enc_settings* settings);