#include <windows.h>

// 画直线
void DrawLine(HDC hdc, int x1, int y1, int x2, int y2, COLORREF color)
{
    HPEN pen = CreatePen(PS_SOLID, 2, color);  // 创建画笔
    HPEN oldPen = SelectObject(hdc, pen);      // 选入画笔

    MoveToEx(hdc, x1, y1, NULL);               // 起点
    LineTo(hdc, x2, y2);                       // 终点

    SelectObject(hdc, oldPen);
    DeleteObject(pen);
}

// 画空心矩形（正方形只要宽高相等）
void DrawRect(HDC hdc, int x, int y, int w, int h, COLORREF color)
{
    HPEN pen = CreatePen(PS_SOLID, 2, color);
    HPEN oldPen = SelectObject(hdc, pen);

    Rectangle(hdc, x, y, x+w, y+h);

    SelectObject(hdc, oldPen);
    DeleteObject(pen);
}

// 画实心矩形
void DrawFillRect(HDC hdc, int x, int y, int w, int h, COLORREF color)
{
    HBRUSH brush = CreateSolidBrush(color);
    HBRUSH oldBrush = SelectObject(hdc, brush);

    Rectangle(hdc, x, y, x+w, y+h);

    SelectObject(hdc, oldBrush);
    DeleteObject(brush);
}

// 画空心圆
void DrawCircle(HDC hdc, int x, int y, int r, COLORREF color)
{
    HPEN pen = CreatePen(PS_SOLID, 2, color);
    HPEN oldPen = SelectObject(hdc, pen);

    Ellipse(hdc, x-r, y-r, x+r, y+r);  // 圆心(x,y) 半径r

    SelectObject(hdc, oldPen);
    DeleteObject(pen);
}

// 画实心圆
void DrawFillCircle(HDC hdc, int x, int y, int r, COLORREF color)
{
    HBRUSH brush = CreateSolidBrush(color);
    HBRUSH oldBrush = SelectObject(hdc, brush);

    Ellipse(hdc, x-r, y-r, x+r, y+r);

    SelectObject(hdc, oldBrush);
    DeleteObject(brush);
}

// 画空心三角形
void DrawTriangle(HDC hdc, int x1,int y1, int x2,int y2, int x3,int y3, COLORREF color)
{
    HPEN pen = CreatePen(PS_SOLID, 2, color);
    HPEN oldPen = SelectObject(hdc, pen);

    MoveToEx(hdc, x1, y1, NULL);
    LineTo(hdc, x2, y2);
    LineTo(hdc, x3, y3);
    LineTo(hdc, x1, y1);

    SelectObject(hdc, oldPen);
    DeleteObject(pen);
}

// 画实心三角形
void DrawFillTriangle(HDC hdc, int x1,int y1, int x2,int y2, int x3,int y3, COLORREF color)
{
    POINT pts[3] = {{x1,y1},{x2,y2},{x3,y3}};
    HBRUSH brush = CreateSolidBrush(color);
    HBRUSH oldBrush = SelectObject(hdc, brush);

    Polygon(hdc, pts, 3);

    SelectObject(hdc, oldBrush);
    DeleteObject(brush);
}