对称算法(计算机图形学)

来源：互联网发布：java 字符串排列组合编辑：程序博客网时间：2024/05/22 00:41
#include<graphics.h>#include<conio.h>#include<iostream>using namespace std;class CPoint{public:int x;int y;CPoint(){}CPoint(int x1,int y1){x=x1;y=y1;}static CPoint ZeroMoveToXY(CPoint p, CPoint XY);//原始坐标向屏幕坐标XY的平移static CPoint ToZero(CPoint p);//关于原点对称static CPoint XYMoveToZero(CPoint p, CPoint XY);//XY坐标向屏幕坐标的平移static CPoint Charge_AllLine(CPoint p, CPoint line_start, CPoint line_end);//关于Ax+By+C = 0对称};//原始坐标向屏幕坐标XY的平移:p.x->(p.x-XY.x)  p.y->(p.y-XY.y)CPoint CPoint::ZeroMoveToXY(CPoint p, CPoint XY){CPoint result;int change[3][3] = {{1,0,0},{0,1,0},{-XY.x,-XY.y,1}};//平移矩阵int p1[3] = {0,0,0};for (int j = 0;j < 3;j++){   p1[j]=p.x * change[0][j] + p.y * change[1][j] + change[2][j];}result.x = p1[0];result.y = p1[1];return result;}//关于原点对称:p.x->p.-x   p.y->p.-yCPoint CPoint::ToZero(CPoint p){CPoint result;int change[3][3] = {{-1,0,0},{0,-1,0},{0,0,1}};int p1[3] = {0,0,0};for (int j = 0;j < 3;j++){    p1[j]=p.x * change[0][j] + p.y * change[1][j] + change[2][j];}result.x = p1[0];result.y = p1[1];return result;}//XY坐标向屏幕坐标的平移:p.x->(p.x+XY.x)  p.y->(p.y+XY.y)CPoint CPoint::XYMoveToZero(CPoint p, CPoint XY){CPoint result;int change[3][3] = {{1,0,0},{0,1,0},{XY.x,XY.y,1}};int p1[3] = {0,0,0};for (int j = 0;j < 3;j++){   p1[j]=p.x * change[0][j] + p.y * change[1][j] + change[2][j];}result.x = p1[0];result.y = p1[1];return result;}//关于直线Ax+By+C = 0对称CPoint CPoint::Charge_AllLine(CPoint p, CPoint line_start, CPoint line_end) {double A,B,C;if(line_start.x == line_end.x){    A = 1;B = 0;C = -line_start.x;}else if(line_start.y == line_end.y){     A = 0;B = 1;C = -line_start.y;}else{A = line_end.y - line_start.y;B = -(line_end.x - line_start.x);C = -line_start.x*(line_end.y-line_start.y)+line_start.y*(line_end.x - line_start.x);}CPoint result;float Y_f = (A*A*p.y - A*B*p.x - B*C)/(B*B+A*A);float X_f = (B*B*p.x - A*B*p.y - A*C)/(B*B+A*A);CPoint xy,m1,m2;//xy为(经过点p且垂直于直线Ax+By+C=0的直线)与(直线Ax+By+C=0)的交点xy.x=X_f;xy.y=Y_f;m1 = CPoint::ZeroMoveToXY(p, xy);//原始坐标向屏幕坐标XY的平移,p.x->(p.x-XY.x)  p.y->(p.y-XY.y)m2 = CPoint::ToZero(m1);//关于原点对称,(p.x-XY.x)->(XY.x-p.x)   (p.y-XY.y)->(XY.y-p.y)result = XYMoveToZero(m2, xy);//XY坐标向屏幕坐标的平移,(XY.x-p.x)->(XY.x-p.x+XY.x)  (XY.y-p.y)->(XY.y-p.y+XY.y)return result;}// 使用中点算法画任意斜率的直线（包括起始点，不包括终止点）void DisplayLine(int x1, int y1, int x2, int y2, int color){int x = x1, y = y1;int a = y1 - y2, b = x2 - x1;int cx = (b >= 0 ? 1 : (b = -b, -1));int cy = (a <= 0 ? 1 : (a = -a, -1));putpixel(x, y, color);int d, d1, d2;if (-a <= b)// 斜率绝对值 <= 1{d = 2 * a + b;d1 = 2 * a;d2 = 2 * (a + b);while(x != x2){if (d < 0)y += cy, d += d2;elsed += d1;x += cx;putpixel(x, y, color);}}else// 斜率绝对值 > 1{d = 2 * b + a; d1 = 2 * b;d2 = 2 * (a + b);while(y != y2) { if(d < 0)d += d1; else x += cx, d += d2; y += cy; putpixel(x, y, color);} }}//画正方形void DisplayRec(int x1,int y1,int x2,int y2,int color){    DisplayLine(x1-50,y1,x2+50,y1,color);DisplayLine(x2,y1-50,x2,y2+50,color);DisplayLine(x2+50,y2,x1-50,y2,color);DisplayLine(x1,y2+50,x1,y1-50,color);}//画三角形void DisplayTriangle(){   DisplayLine(100,100,300,125,RED);   DisplayLine(100,100,200,225,RED);   DisplayLine(300,125,200,225,RED);}//显示图形void Display(){int n=3,x,y,i;//画三角形CPoint *p=new CPoint[3];p[0].x=100;p[0].y=100;p[1].x=300;p[1].y=125;p[2].x=200;p[2].y=225;//画直线CPoint *p2=new CPoint[2];p2[0].x=350;p2[0].y=60;p2[1].x=180;p2[1].y=400;//DisplayLine(350,60,180,400,GREEN);int gdriver=DETECT, gmode;initgraph(&gdriver,&gmode,"");//根据测试结果初始化图形界面//画多边形for(i=1;i<n;i++){DisplayLine(p[i-1].x,p[i-1].y,p[i].x,p[i].y,RED);if(i==n-1){        DisplayLine(p[n-1].x,p[n-1].y,p[0].x,p[0].y,RED);}}       //画直线    DisplayLine(p2[0].x,p2[0].y,p2[1].x,p2[1].y,GREEN);//顶点按矩阵复合变换for(i=0;i<n;i++){p[i]=CPoint::Charge_AllLine(p[i], p2[0], p2[1]);}//画对称后的多边形    for(i=1;i<n;i++){DisplayLine(p[i-1].x,p[i-1].y,p[i].x,p[i].y,RED);if(i==n-1){        DisplayLine(p[n-1].x,p[n-1].y,p[0].x,p[0].y,RED);}}}// 主函数void main(){Display();// 按任意键退出getch();closegraph();}
0 0