平面物理引擎（我們的星星）3.0 -- 測試程序示例

（我們的星星）3.0 – 測試程序示例

前面已經有了源碼，這邊就放一個測試程序

#include<iostream>//輸入輸出流
#include<time.h>//時間
#include<vector>//vector容器
#include<starx.h>//我們的星星類頭文件

#include<fstream>//文件讀寫流


using namespace std;//引用命名空間std

void Write2file(ofstream& output, const double &data)
{
    output<<data<<endl;
}


//void cd(const starx& g){
//    g.speed(x);
//}

int main()
{
	/*準備三個文件流用以存放座標數據*/
    ofstream output1x("D:\\Lists\\Matlab\\application\\movedatax.txt",ofstream::out|ofstream::trunc);
    ofstream output1y("D:\\Lists\\Matlab\\application\\movedatay.txt",ofstream::out|ofstream::trunc);

    ofstream output2x("D:\\Lists\\Matlab\\application\\movedata2x.txt",ofstream::out|ofstream::trunc);
    ofstream output2y("D:\\Lists\\Matlab\\application\\movedata2y.txt",ofstream::out|ofstream::trunc);

    ofstream output3x("D:\\Lists\\Matlab\\application\\movedata3x.txt",ofstream::out|ofstream::trunc);
    ofstream output3y("D:\\Lists\\Matlab\\application\\movedata3y.txt",ofstream::out|ofstream::trunc);

	/* 定義三顆星星 */
    starx xx2(2,3,0,-18,1);//(0,1.3)位置 初始速度（0，-1）質量1
    starx xx(0,0,0,-18,1);//(0,1)位置 初始速度（0，-1）質量1
    starx t0(1,0,0,0,50);
   
	/*設置計時器（作爲時間基準，參考頭文件<time.h>）*/
    clock_t now;
    double dtime=0;
    now = clock();//zero = now;


    int tt=0;
    while(tt<70000)//計算星星們的座標70000次
    {
		/* 當時間變化可見時 （避免循環間隔過短造成計算次數不足）*/
        if(now != clock())
        {
        		/* 指明受力集合 */
        		vector<starx> stx1={t0};//xx受力來源
                vector<starx> stx2={t0,xx};
                vector<starx> stx3={xx,xx2};

                dtime = ((double)(clock()-now))/CLK_TCK;
                /* 計算上一個時間間隔的位移 */
                xx.kinesis(dtime);
                xx2.kinesis(dtime);
                //t0.kinesis(dtime);
                /*計算受力（實際上是合力）*/
                xx.gravitation(stx1);
                xx2.gravitation(stx2);
                //t0.gravitation(stx3);
                /*加速度*/
                xx.accelerate();
                xx2.accelerate();
                //t0.accelerate();
                /* 速度 */
                xx.velocity(dtime);
                xx2.velocity(dtime);
                //t0.velocity(dtime);
                now = clock();
                tt++;

                cout<<"location:"<<xx.location(x)<<","<<xx.location(y)
                <<"\tvelocity:"<<xx.speed(y)
                <<"\tforce:"<<xx.force(x)<<","<<xx.force(y)<<endl;

                //記錄x、y座標到對應文件中
                Write2file(output1x,xx.location(x));
                Write2file(output1y,xx.location(y));

                Write2file(output2x,xx2.location(x));
                Write2file(output2y,xx2.location(y));

                Write2file(output3x,t0.location(x));
                Write2file(output3y,t0.location(y));

        }
    }
    now = clock();

    //cout<<"run time:"<<(double)(now-zero)/CLK_TCK<<endl;
    return 0;
}

---

然後使用matlab繪製軌跡曲線

• 代碼如下：

%分析平面物理模型的數據

%載入數據
load movedatax.txt;
load movedatay.txt;
load movedata2x.txt;
load movedata2y.txt;
load movedata3x.txt;
load movedata3y.txt;
data1x = movedatax;
data1y = movedatay;
data2x = movedata2x;
data2y = movedata2y;
data3x = movedata3x;
data3y = movedata3y;
%構建x軸離散點   --與data等長
%xis = 1:length(data);
%繪製散點圖
%plot(xis,data,'x');
%hold on;
%subplot(1,2,2);
%format;
hold on;
plot(data1x,data1y);
plot(data2x,data2y);
plot(data3x,data3y);%平滑曲線方便觀察數據特徵
title("質點運動軌跡(70000點數據)");
xlabel("x座標");
ylabel("y座標");
% hold on;
plot(2,3,'bx');
plot(0,0,'rx');
plot(1,0,'gx');

---

看看結果

放大看看

ok

準備工作(類的設計思路&頭文件)：https://blog.csdn.net/qq_33904382/article/details/102757667

類源文件(.cpp)：
https://blog.csdn.net/qq_33904382/article/details/102789576