我想把直线和矩形的绘制记录放在一个vector数组中，并且能够一直画直线或者矩形，但是在用当前形状为直线时，测试之后只能画出一条直线，猜测是无法获取鼠标左键再次按下的消息，所以在此请教

#include <iostream>
#include <easyx.h>
#include <vector>
using namespace std;


//定义形状类型枚举
enum ShapeType
{
	ShapeLine,  //线段
	ShapeRect   //矩形
};

int g_begx, g_begy;
bool isPress = false;  //鼠标是否按下
int g_shapetype = ShapeLine;  //当前形状
vector<void*> g_shapes;  //存储所有形状


class Line
{
private:
	int type;  //形状
	int x1;
	int y1;
	int x2;
	int y2;
	COLORREF color;  //颜色
	int line_Th;  //线宽
	vector<void*> g_shapes;  //存储所有形状

public:
	Line()
	{
	}

	Line(int x1, int y1, int x2, int y2, COLORREF color, int line_Th)
	{
		this->type = ShapeLine;
		this->x1 = x1;
		this->y1 = y1;
		this->x2 = x2;
		this->y2 = y2;
		this->color = color;
		this->line_Th = line_Th;
	}

	~Line()
	{
	}

	void line_draw()
	{
		setlinecolor(this->color);
		setlinestyle(PS_SOLID, this->line_Th);
		line(this->x1, this->y1, this->x2, this->y2);
	}

	int GetType()
	{
		return this->type;
	}

	void SetType(int t)
	{
		this->type = t;
	}

	int GetX1()
	{
		return this->x1;
	}

	void SetX1(int x)
	{
		this->x1 = x;
	}

	int GetY1()
	{
		return this->y1;
	}

	void SetY1(int y)
	{
		this->y1 = y;
	}

	int GetX2()
	{
		return this->x2;
	}

	void SetX2(int x)
	{
		this->x2 = x;
	}

	int GetY2()
	{
		return this->y2;
	}

	void SetY2(int y)
	{
		this->y2 = y;
	}

	COLORREF GetColor()
	{
		return this->color;
	}

	void SetColor(COLORREF c)
	{
		this->color = c;
	}

	int Getline_Th()
	{
		return this->line_Th;
	}

	void Setline_Th(int lt)
	{
		this->line_Th = lt;
	}
};


class Rect :public Line
{
public:
	Rect()
	{
	}

	Rect(int x1, int y1, int x2, int y2, COLORREF color, int line_Th)
	{
		Rect r(int x1, int y1, int x2, int y2, COLORREF color, int line_Th);
		this->SetType(ShapeRect);
	}

	~Rect()
	{
	}

	void rect_draw()
	{
		setlinecolor(this->GetColor());
		setlinestyle(PS_SOLID, this->Getline_Th());
		rectangle(this->GetX1(), this->GetY1(), this->GetX2(), this->GetY2());
	}
};


//消息处理函数
//鼠标左键按下处理
void mouseButtomDown(ExMessage* msg)
{
	isPress = true;
	//记录鼠标按下的坐标
	g_begx = msg->x;
	g_begy = msg->y;
}

//鼠标左键弹起处理
void mouseButtomUP(ExMessage* msg)
{
	isPress = false;

	//判断当前绘制的形状是什么
	if (g_shapetype == ShapeLine)
	{
		Line line(g_begx, g_begy, msg->x, msg->y, RED, 2);
		Line* l = new Line;
		l = &line;
		g_shapes.push_back(l);
	}
	else if (g_shapetype == ShapeRect)
	{
		Rect rect(g_begx, g_begy, msg->x, msg->y, RED, 2);
		Line* r = new Rect;
		r = &rect;
		g_shapes.push_back(r);
	}
}

//鼠标移动处理
void mouseButtomMOVE(ExMessage* msg)
{
	//鼠标左键按下并移动，就开始绘制
	if (isPress)
	{
		cleardevice();  //清屏重绘
		setlinecolor(RED);
		switch (g_shapetype)
		{
		case ShapeLine:
			//画直线
			line(g_begx, g_begy, msg->x, msg->y);
			break;
		case ShapeRect:
			//画矩形
			rectangle(g_begx, g_begy, msg->x, msg->y);
			break;
		}

	}
}


int main()
{
	initgraph(640, 480, EX_SHOWCONSOLE);//创建窗口
	setbkcolor(WHITE);//设置背景颜色为白色
	cleardevice();//清屏

	BeginBatchDraw();  //双缓冲，防止闪屏
	while (true)
	{
		//绘制
		for (int i = 0; i < g_shapes.size(); i++)
		{
			(*(Line*)g_shapes[i]).line_draw();
		}


		//消息处理 鼠标消息
		static ExMessage msg;
		if (peekmessage(&msg, EX_MOUSE))
		{
			//消息分发
			switch (msg.message)
			{
			case WM_LBUTTONDOWN:  //鼠标左键按下
				mouseButtomDown(&msg);
				break;
			case WM_LBUTTONUP:  //鼠标左键弹起
				mouseButtomUP(&msg);
				break;
			case WM_MOUSEMOVE:  //鼠标移动
				mouseButtomMOVE(&msg);
				break;
			}
		}

		FlushBatchDraw();
	}
	EndBatchDraw();

	getchar();
	return 0;
}