env.grid_colours(c + coord_def(x, y)) = colour;

                dgn_set_grid_colour_at(c + coord_def(x, y), colour);

void dgn_set_grid_colour_at(const coord_def &c, int colour);

static void dgn_load_colour_grid();
static void dgn_map_colour_fixup();

struct coloured_feature
{
    dungeon_feature_type feature;
    int                  colour;
    coloured_feature() : feature(DNGN_UNSEEN), colour(BLACK) { }
    coloured_feature(dungeon_feature_type f, int c)
        : feature(f), colour(c)
    {
    }
};

struct dgn_colour_override_manager
{
    dgn_colour_override_manager()
    {
        dgn_load_colour_grid();
    }
    ~dgn_colour_override_manager()
    {
        dgn_map_colour_fixup();
    }
};
typedef FixedArray< coloured_feature, GXM, GYM > dungeon_colour_grid;
static std::auto_ptr<dungeon_colour_grid> dgn_colour_grid;

        {
            dgn_map_colour_fixup();

        }

static void dgn_load_colour_grid()
{
    dgn_colour_grid.reset(new dungeon_colour_grid);
    dungeon_colour_grid &dcgrid(*dgn_colour_grid);
    for (int y = Y_BOUND_1; y <= Y_BOUND_2; ++y)
        for (int x = X_BOUND_1; x <= X_BOUND_2; ++x)
            if (env.grid_colours[x][y] != BLACK)
                dcgrid[x][y] =
                    coloured_feature(grd[x][y], env.grid_colours[x][y]);
}
static void dgn_map_colour_fixup()
{
    if (!dgn_colour_grid.get())
        return;
    // If the original coloured feature has been changed, reset the colour.
    const dungeon_colour_grid &dcgrid(*dgn_colour_grid);
    for (int y = Y_BOUND_1; y <= Y_BOUND_2; ++y)
        for (int x = X_BOUND_1; x <= X_BOUND_2; ++x)
            if (dcgrid[x][y].colour != BLACK
                && grd[x][y] != dcgrid[x][y].feature)
            {
                env.grid_colours[x][y] = BLACK;
            }
    dgn_colour_grid.reset(NULL);
}

void dgn_set_grid_colour_at(const coord_def &c, int colour)
{
    if (colour != BLACK)
    {
        env.grid_colours(c) = colour;
        if (!dgn_colour_grid.get())
            dgn_colour_grid.reset( new dungeon_colour_grid );
        (*dgn_colour_grid)(c) = coloured_feature(grd(c), colour);
    }
}

    dgn_colour_grid.reset(NULL);
    

    const dgn_colour_override_manager colour_man;