未解析的外部符号，但函数已定义并实现

问：

我有一个头文件，定义了类：chunk

#pragma once
#include <vector>

#include "Tile.h"
#include "Numerics.h"
namespace boch {
    class chunk {
    public:
        chunk();
        static const uint defsize_x = 16;
        static const uint defsize_y = 16;
        std::vector<std::vector<tile*>> tilespace;

        

        tile* getat(vint coords);
        void fillc(tile t);
    };
}

然后，我在文件中定义了类的实现：Chunk.cpp

#include "Chunk.h"

boch::chunk::chunk() {
    tilespace = std::vector<std::vector<tile*>>(defsize_x);
    for (int x = 0; x < defsize_x; x++) {
        std::vector<tile*> temp = std::vector<tile*>(defsize_y);
        tilespace[x] = temp;
    }
}

void boch::chunk::fillc(tile t) {
    for (int x = 0; x < defsize_x; x++) {
        for (int y = 0; y < defsize_y; y++) {
            tilespace[x][y] = new tile(t);
        }
    }
}

boch::tile* boch::chunk::getat(vint coords) {
    return tilespace[coords.x][coords.y];
}

(vint是一个 typedef，其是自定义 X，Y 向量，如果有帮助的话）boch::vector<int>

然后，我在文件的 main 函数中使用它：BochGrounds.cpp

#include <iostream>
#include "Layer.h"
#include "Gamegrid.h"

int main()
{
    boch::layer newlayer = boch::layer(boch::vuint(16, 16));
    boch::chunk newchunk = boch::chunk();
    boch::gamegrid newgrid = boch::gamegrid();

    newchunk.fillc(boch::tile());
    newgrid.addchunk(boch::cv_zero, &newchunk);
    newgrid.drawtolayer(&newlayer);
    newlayer.draw(std::cout);
}

Tile 类定义了 gamegrid 类，chunk 包括 tile 类，gamegrid 包括 chunk & entity（也包括 tile）。图层类仅包含切片。所有头文件都有指令。尝试编译时，出现以下错误：#pragma once

LNK2019 unresolved external symbol "public: __cdecl boch::chunk::chunk(void)" (??0chunk@boch@@QEAA@XZ) referenced in function main

LNK2019 unresolved external symbol "public: void __cdecl boch::chunk::fillc(class boch::tile)" (?fillc@chunk@boch@@QEAAXVtile@2@@Z) referenced in function main

结果：

LNK1120 2 unresolved externals

其他 StackOverflow 答案表明链接器无法看到 both 和 chunk 构造函数的实现，但我不明白为什么它甚至是这里的问题。请帮忙。（链接器设置尚未更改，并且是 MVSC 2019 的默认设置）fillc()