我想知道您是否可以帮助我调试我的一些代码。我已经为一个我们正在实现多边形逼近算法的类项目编写了以下代码。但我似乎无法让代码做我想做的事情。这是该算法的维基文章的链接：http ://en.wikipedia.org/wiki/Ramer%E2%80%93Douglas%E2%80%93Peucker_algorithm
我遇到的问题是第二个数组 closedStack 要么没有正确更新内部的值，要么没有正确显示。但是第一个数组，即从文件中读取的数组正确显示。我还不断收到已满的 closedStack 错误，因此我将 if 语句更改为不使用 fileSize 变量，因此它也可能存在问题。如果您需要我解释任何逻辑或变量等，请询问，我会解释。
#include "math.h"
#include <iostream>
#include <fstream>
#include "glut.h"
using namespace std;
struct point{
int x, y;
};
void display(void);
void fileRead();
void oPush(point);
void cPush(point);
point oPop();
int deviation();
point pixel[2000];
int fileSize = 0;
int errorAllowed= 5;
int errorDeviation=0;
int oTop = 0;
int cTop = 0;
point first;
point last;
point openStack[5000];
point closedStack[5000];
int V1 = 0;
int V2 = 0;
void main(int argc, char **argv){
fileRead();
glutInit(&argc, argv);
glutInitDisplayMode(GLUT_SINGLE | GLUT_RGB);
glutInitWindowSize(500,500);
glutInitWindowPosition(75,75);
glutCreateWindow("Ramer's Iterative Algorithm");
glutDisplayFunc(display);
gluOrtho2D(0,500,0,500);
fileSize = fileSize/2;
int tmp1 = pixel[0].x+pixel[0].y;
int tmp2 = 0;
for(int i = 0; i<2000; i++){
tmp2 = pixel[i].x+pixel[i].y;
if(tmp2 < tmp1){
tmp1 = tmp2;
V1 = i;
}
}
for(int i = 0; i<2000; i++){
tmp2 = pixel[i].x+pixel[i].y;
if(tmp2 > tmp1){
tmp1 = tmp2;
V2 = i;
}
}
oPush(pixel[V1]);
oPush(pixel[V2]);
oPush(pixel[V1]);
do{
first = oPop();
last = oPop();
int Mid = deviation();
if(errorDeviation>errorAllowed){
oPush(last);
oPush(pixel[Mid]);
oPush(first);
}
else if(errorDeviation<=errorAllowed){
oPush(last);
cPush(first);
}
}while(oTop>=2);
glutMainLoop();
cin >> V1;
}
void display(void){
glClearColor(0,0,0,0);
glClear(GL_COLOR_BUFFER_BIT);
glColor3f(1,1,1);
glBegin(GL_POINTS);
for(int i=0; i<2000; i++)
glVertex2i(pixel[i].x,pixel[i].y);
glEnd();
glColor3f(1,0,0);
glBegin(GL_LINE_STRIP);
for(int i=0;i<=cTop; i++)
glVertex2i(closedStack[i].x,closedStack[i].y);
glEnd();
glFlush();
}
void fileRead(){
char fileName[20];
cout << "Enter the name of the file you would like to parse data from: ";
cin >> fileName;
ifstream boundary;
boundary.open(fileName);
if(boundary.fail()){
cout << "Could not open '" << fileName << "' for reading.\n";
exit(0);
}
for(int i=0; !boundary.eof(); i++){
boundary >> pixel[i].x;
boundary >> pixel[i].y;
fileSize ++;
}
}
void oPush(point p){
if(oTop>fileSize){
cout << "Full Stack--Open\n";
exit(0);
}
else{
oTop++;
openStack[oTop]= p;
}
}
void cPush(point p){
if(cTop>10000){
cout << "Full Stack--Closed\n";
exit(0);
}
else{
cTop++;
closedStack[cTop]= p;
}
}
point oPop(){
point temp;
if(oTop<=0){
cout << "Stack Empty\n";
exit(0);
}
else{
temp = pixel[oTop];
oTop--;
}
return temp;
}
int deviation(){
float y = last.y-first.y;
float x = last.x-first.x;
float theta = atan(y/x);
int most = 0;
for(int i = V1+1; i < V2; i++){
float ped = (-(pixel[i].x-first.x)*sin(theta))+((pixel[i].y-last.y)*cos(theta));
float errDev= abs(ped);
if(errDev>most)
most = i;
errorDeviation = (int)errDev;
}
return most;
}
为了详细说明 V1 和 V2，它们应该是数组的左下角和右上角。检查我的循环已简化为：
for(int i = 0; i<fileSize; i++){
tmp2 = (pixel[i].x)+(pixel[i].y);
if(tmp2 <= tmp1){
tmp1 = tmp2;
V1 = i;
}
if(tmp2 >= tmp1){
tmp1 = tmp2;
V2 = i;
}
循环将点的 x+y 加在一起，然后将其与前一个点进行检查以更新它。x+y 最低的点最终应该是 V1，最高的点应该是 V2。但我认为循环运行不正常。通过放大绘制的内容，显示循环的第二部分只有三个点。它看起来像初始数组的第一个和第二个点以及 0,0 被绘制。不知道为什么会这样。