c++-Raylib为什么我的矩形列不能工作？

这是一张图片：https://i.stack.imgur.com/q5Th5.png

这是我的密码

struct Mat
{
    float X, Y;
    float SpeedX, SpeedY;
    float Force;
    float Gravity;
    Vector2 MousePos;
    Vector2 size;
    Color color;

    Rectangle GetShape() {
        return Rectangle{ MousePos.x, MousePos.y, size.x, size.y };
    }
    void DrawMat() {
       
 DrawRectangleRec(GetShape(), color);
        MousePos.y += 9.81f;

        if (MousePos.y < 0) {
            MousePos.y *= -1;
        }
        else if (MousePos.y > GetScreenHeight() - size.y) {
            MousePos.y = GetScreenHeight() - size.y;
        }
    }
};

int main() {
    InitWindow(800, 600, "Speed Z Presends to you... Satisfiying, Amazing, Niffty, Dreamy. SIMULATOR");
    SetWindowState(FLAG_VSYNC_HINT);
    Mat Sand;
    
    Sand.MousePos = { -100, -100 };
    Sand.size = { 5, 5 };
    Sand.color = YELLOW;
    Sand.X = Sand.MousePos.x;
    Sand.Y = Sand.MousePos.y;
    Sand.SpeedX = 300;
    Sand.SpeedY = 500;
    Mat Brick;

    Brick.MousePos = { -100, -100 };
    Brick.size = { 5, 5 };
    Brick.color = RED;


    Vector2 Mousepos = {-100, -100};
    bool Mouseclicked = false;
    Vector2 RectSize = { 2, 2 };
    int Numof = 0;
    std::vector positions = {};
    while (!WindowShouldClose())
    {
        if (CheckCollisionRecs(Sand.GetShape() , Brick.GetShape()))
        {
            
            Sand.color = GREEN;
        }
        
        
        
        BeginDrawing();



        ClearBackground(BLACK);
    
        for (size_t i = 0; i < positions.size(); i++)
        {
            positions[i].DrawMat();
        }



            if (IsKeyPressed(KEY_ONE)) {
                Numof = 1;
                
            }

            if (Numof == 1)
            {
                if (IsMouseButtonPressed(MOUSE_BUTTON_LEFT))
                {
                    Mouseclicked = true;
                    Mousepos = GetMousePosition();
                    Sand.MousePos = GetMousePosition();
                    positions.push_back(Sand);

                }
                
            }
            
            if (IsKeyPressed(KEY_TWO)) {
                Numof = 2;

            }

            if (Numof == 2) {
                if (IsMouseButtonPressed(MOUSE_BUTTON_LEFT))
                {
                    Mouseclicked = true;
                    Mousepos = GetMousePosition();
                    Brick.MousePos = GetMousePosition();
                    positions.push_back(Brick);
                }
            }
            
            
        DrawFPS(10, 10);
        EndDrawing();




        CloseWindow();
    }
    
    return 0;
}