unity/crnlib/crn_pixel_format.cpp

// File: crn_pixel_format.cpp
// See Copyright Notice and license at the end of inc/crnlib.h
#include "crn_core.h"
#include "crn_pixel_format.h"
#include "crn_image.h"

namespace crnlib {
namespace pixel_format_helpers {
const pixel_format g_all_pixel_formats[] =
    {
        PIXEL_FMT_DXT1,
        PIXEL_FMT_DXT2,
        PIXEL_FMT_DXT3,
        PIXEL_FMT_DXT4,
        PIXEL_FMT_DXT5,
        PIXEL_FMT_3DC,
        PIXEL_FMT_DXN,
        PIXEL_FMT_DXT5A,
        PIXEL_FMT_DXT5_CCxY,
        PIXEL_FMT_DXT5_xGxR,
        PIXEL_FMT_DXT5_xGBR,
        PIXEL_FMT_DXT5_AGBR,
        PIXEL_FMT_DXT1A,
        PIXEL_FMT_ETC1,
        PIXEL_FMT_R8G8B8,
        PIXEL_FMT_L8,
        PIXEL_FMT_A8,
        PIXEL_FMT_A8L8,
        PIXEL_FMT_A8R8G8B8};

uint get_num_formats() {
  return sizeof(g_all_pixel_formats) / sizeof(g_all_pixel_formats[0]);
}

pixel_format get_pixel_format_by_index(uint index) {
  CRNLIB_ASSERT(index < get_num_formats());
  return g_all_pixel_formats[index];
}

const char* get_pixel_format_string(pixel_format fmt) {
  switch (fmt) {
    case PIXEL_FMT_INVALID:
      return "INVALID";
    case PIXEL_FMT_DXT1:
      return "DXT1";
    case PIXEL_FMT_DXT1A:
      return "DXT1A";
    case PIXEL_FMT_DXT2:
      return "DXT2";
    case PIXEL_FMT_DXT3:
      return "DXT3";
    case PIXEL_FMT_DXT4:
      return "DXT4";
    case PIXEL_FMT_DXT5:
      return "DXT5";
    case PIXEL_FMT_3DC:
      return "3DC";
    case PIXEL_FMT_DXN:
      return "DXN";
    case PIXEL_FMT_DXT5A:
      return "DXT5A";
    case PIXEL_FMT_DXT5_CCxY:
      return "DXT5_CCxY";
    case PIXEL_FMT_DXT5_xGxR:
      return "DXT5_xGxR";
    case PIXEL_FMT_DXT5_xGBR:
      return "DXT5_xGBR";
    case PIXEL_FMT_DXT5_AGBR:
      return "DXT5_AGBR";
    case PIXEL_FMT_ETC1:
      return "ETC1";
    case PIXEL_FMT_R8G8B8:
      return "R8G8B8";
    case PIXEL_FMT_A8R8G8B8:
      return "A8R8G8B8";
    case PIXEL_FMT_A8:
      return "A8";
    case PIXEL_FMT_L8:
      return "L8";
    case PIXEL_FMT_A8L8:
      return "A8L8";
    default:
      break;
  }
  CRNLIB_ASSERT(false);
  return "?";
}

const char* get_crn_format_string(crn_format fmt) {
  switch (fmt) {
    case cCRNFmtDXT1:
      return "DXT1";
    case cCRNFmtDXT3:
      return "DXT3";
    case cCRNFmtDXT5:
      return "DXT5";
    case cCRNFmtDXT5_CCxY:
      return "DXT5_CCxY";
    case cCRNFmtDXT5_xGBR:
      return "DXT5_xGBR";
    case cCRNFmtDXT5_AGBR:
      return "DXT5_AGBR";
    case cCRNFmtDXT5_xGxR:
      return "DXT5_xGxR";
    case cCRNFmtDXN_XY:
      return "DXN_XY";
    case cCRNFmtDXN_YX:
      return "DXN_YX";
    case cCRNFmtDXT5A:
      return "DXT5A";
    case cCRNFmtETC1:
      return "ETC1";
    default:
      break;
  }
  CRNLIB_ASSERT(false);
  return "?";
}

component_flags get_component_flags(pixel_format fmt) {
  // These flags are for *uncooked* pixels, i.e. after after adding Z to DXN maps, or converting YCC maps to RGB, etc.

  uint flags = cCompFlagRValid | cCompFlagGValid | cCompFlagBValid | cCompFlagAValid | cCompFlagGrayscale;
  switch (fmt) {
    case PIXEL_FMT_DXT1:
    case PIXEL_FMT_ETC1: {
      flags = cCompFlagRValid | cCompFlagGValid | cCompFlagBValid;
      break;
    }
    case PIXEL_FMT_DXT1A: {
      flags = cCompFlagRValid | cCompFlagGValid | cCompFlagBValid | cCompFlagAValid;
      break;
    }
    case PIXEL_FMT_DXT2:
    case PIXEL_FMT_DXT3: {
      flags = cCompFlagRValid | cCompFlagGValid | cCompFlagBValid | cCompFlagAValid;
      break;
    }
    case PIXEL_FMT_DXT4:
    case PIXEL_FMT_DXT5: {
      flags = cCompFlagRValid | cCompFlagGValid | cCompFlagBValid | cCompFlagAValid;
      break;
    }
    case PIXEL_FMT_DXT5A: {
      flags = cCompFlagAValid;
      break;
    }
    case PIXEL_FMT_DXT5_CCxY: {
      flags = cCompFlagRValid | cCompFlagGValid | cCompFlagBValid | cCompFlagLumaChroma;
      break;
    }
    case PIXEL_FMT_DXT5_xGBR: {
      flags = cCompFlagRValid | cCompFlagGValid | cCompFlagBValid | cCompFlagNormalMap;
      break;
    }
    case PIXEL_FMT_DXT5_AGBR: {
      flags = cCompFlagRValid | cCompFlagGValid | cCompFlagBValid | cCompFlagAValid | cCompFlagNormalMap;
      break;
    }
    case PIXEL_FMT_DXT5_xGxR: {
      flags = cCompFlagRValid | cCompFlagGValid | cCompFlagBValid | cCompFlagNormalMap;
      break;
    }
    case PIXEL_FMT_3DC: {
      flags = cCompFlagRValid | cCompFlagGValid | cCompFlagBValid | cCompFlagNormalMap;
      break;
    }
    case PIXEL_FMT_DXN: {
      flags = cCompFlagRValid | cCompFlagGValid | cCompFlagBValid | cCompFlagNormalMap;
      break;
    }
    case PIXEL_FMT_R8G8B8: {
      flags = cCompFlagRValid | cCompFlagGValid | cCompFlagBValid;
      break;
    }
    case PIXEL_FMT_A8R8G8B8: {
      flags = cCompFlagRValid | cCompFlagGValid | cCompFlagBValid | cCompFlagAValid;
      break;
    }
    case PIXEL_FMT_A8: {
      flags = cCompFlagAValid;
      break;
    }
    case PIXEL_FMT_L8: {
      flags = cCompFlagRValid | cCompFlagGValid | cCompFlagBValid | cCompFlagGrayscale;
      break;
    }
    case PIXEL_FMT_A8L8: {
      flags = cCompFlagRValid | cCompFlagGValid | cCompFlagBValid | cCompFlagAValid | cCompFlagGrayscale;
      break;
    }
    default: {
      CRNLIB_ASSERT(0);
      break;
    }
  }
  return static_cast<component_flags>(flags);
}

crn_format convert_pixel_format_to_best_crn_format(pixel_format crn_fmt) {
  crn_format fmt = cCRNFmtDXT1;
  switch (crn_fmt) {
    case PIXEL_FMT_DXT1:
    case PIXEL_FMT_DXT1A:
      fmt = cCRNFmtDXT1;
      break;
    case PIXEL_FMT_DXT2:
    case PIXEL_FMT_DXT3:
    case PIXEL_FMT_DXT4:
    case PIXEL_FMT_DXT5:
      fmt = cCRNFmtDXT5;
      break;
    case PIXEL_FMT_3DC:
      fmt = cCRNFmtDXN_YX;
      break;
    case PIXEL_FMT_DXN:
      fmt = cCRNFmtDXN_XY;
      break;
    case PIXEL_FMT_DXT5A:
      fmt = cCRNFmtDXT5A;
      break;
    case PIXEL_FMT_R8G8B8:
    case PIXEL_FMT_L8:
      fmt = cCRNFmtDXT1;
      break;
    case PIXEL_FMT_A8R8G8B8:
    case PIXEL_FMT_A8:
    case PIXEL_FMT_A8L8:
      fmt = cCRNFmtDXT5;
      break;
    case PIXEL_FMT_DXT5_CCxY:
      fmt = cCRNFmtDXT5_CCxY;
      break;
    case PIXEL_FMT_DXT5_xGBR:
      fmt = cCRNFmtDXT5_xGBR;
      break;
    case PIXEL_FMT_DXT5_AGBR:
      fmt = cCRNFmtDXT5_AGBR;
      break;
    case PIXEL_FMT_DXT5_xGxR:
      fmt = cCRNFmtDXT5_xGxR;
      break;
    case PIXEL_FMT_ETC1:
      fmt = cCRNFmtETC1;
      break;
    default: {
      CRNLIB_ASSERT(false);
      break;
    }
  }
  return fmt;
}

pixel_format convert_crn_format_to_pixel_format(crn_format fmt) {
  switch (fmt) {
    case cCRNFmtDXT1:
      return PIXEL_FMT_DXT1;
    case cCRNFmtDXT3:
      return PIXEL_FMT_DXT3;
    case cCRNFmtDXT5:
      return PIXEL_FMT_DXT5;
    case cCRNFmtDXT5_CCxY:
      return PIXEL_FMT_DXT5_CCxY;
    case cCRNFmtDXT5_xGxR:
      return PIXEL_FMT_DXT5_xGxR;
    case cCRNFmtDXT5_xGBR:
      return PIXEL_FMT_DXT5_xGBR;
    case cCRNFmtDXT5_AGBR:
      return PIXEL_FMT_DXT5_AGBR;
    case cCRNFmtDXN_XY:
      return PIXEL_FMT_DXN;
    case cCRNFmtDXN_YX:
      return PIXEL_FMT_3DC;
    case cCRNFmtDXT5A:
      return PIXEL_FMT_DXT5A;
    case cCRNFmtETC1:
      return PIXEL_FMT_ETC1;
    default: {
      CRNLIB_ASSERT(false);
      break;
    }
  }

  return PIXEL_FMT_INVALID;
}

}  // namespace pixel_format

}  // namespace crnlib