Function Image_GetAstcHeader

engine/gamesys/src/gamesys/scripts/script_image.cpp:359–396

get the header of an .astc buffer * get the header of an .astc buffer * * @name image.get_astc_header * @param buffer [type:string] .astc file data buffer * * @return table [type:table|nil] header or `nil` if buffer is not a valid .astc. The header has these fields: * * - [type:number] `width`: image width * - [type:number] `height`: image height * - [type:n

    * ```
    */
    int Image_GetAstcHeader(lua_State* L)
    {
        int top = lua_gettop(L);
        luaL_checktype(L, 1, LUA_TSTRING);
        size_t data_len = 0;
        const char* data = lua_tolstring(L, 1, &data_len);

        uint32_t width, height, depth;
        if (!dmImage::GetAstcDimensions((void*)data, (uint32_t)data_len, &width, &height, &depth))
        {
            return luaL_error(L, "Data is not a valid .astc file");
        }

        uint32_t block_size_x, block_size_y, block_size_z;
        if (!dmImage::GetAstcBlockSize((void*)data, (uint32_t)data_len, &block_size_x, &block_size_y, &block_size_z))
        {
            return luaL_error(L, "Data is not a valid .astc file");
        }

        lua_newtable(L);

            lua_pushinteger(L, width);
            lua_setfield(L, -2, "width");
            lua_pushinteger(L, height);
            lua_setfield(L, -2, "height");
            lua_pushinteger(L, depth);
            lua_setfield(L, -2, "depth");

            lua_pushinteger(L, block_size_x);
            lua_setfield(L, -2, "block_size_x");
            lua_pushinteger(L, block_size_y);
            lua_setfield(L, -2, "block_size_y");
            lua_pushinteger(L, block_size_z);
            lua_setfield(L, -2, "block_size_z");

        assert(top + 1 == lua_gettop(L));
        return 1;
    }

    static const luaL_reg ScriptImage_methods[] =
    {