我编写了一个程序，它接收一个文本文件作为输入并返回另一个文本文件作为输出。文本文件是使用 3D 应用程序 (Blender) 中的脚本 (python) 创建的，它包含一个顶点列表，这些顶点是方形网格的一部分。该程序接收该数据，将其存储在一个结构中，并返回一个形成较小正方形的顶点列表。然后，3D 应用程序再次使用脚本读取此顶点并将它们与原始网格分开。这样做几次，原来的网格将被分成许多相同面积的正方形。到现在为止，它可以工作了；）但是非常低..在 200k 顶点上执行它需要一段时间，但是在 1kk 顶点上运行它需要很长时间
这里的来源：
#include <stdio.h>
#include <stdlib.h>
#include <malloc.h>
typedef struct{
int index;
float x,y,z;
} vertex;
vertex *find_vertex(vertex *list, int len)
{
int i;
vertex lower,highter;
lower=list[0];
highter=list[1];
//find the lower lefter and the upper righter vertices
for(i=0;i<len;i++)
{
if ((list[i].x<=lower.x) && (list[i].y<=lower.y))
lower=list[i];
if ((list[i].x>=highter.x) && (list[i].y>=highter.y))
highter=list[i];
}
vertex *ret;//create a pointer for returning 2 structs
ret=(vertex*)malloc(sizeof(vertex)*2);
if (ret==NULL)
{
printf("Can't allocate the memory");
return 0;
}
ret[0]=lower;
ret[1]=highter;
return ret;
}
vertex *square_list_of_vertex(vertex *list,int len,vertex start, float size)
{
int i=0,a=0;
unsigned int *num;
num=(int*)malloc(sizeof(unsigned int)*len);
if (num==NULL)
{
printf("Can't allocate the memory");
return 0;
}
//controlls if point is in the right position and adds its index in the main list in another array
for(i=0;i<len;i++)
{
if ((list[i].x-start.x)<size && (list[i].y-start.y<size))
{
if (list[i].y-start.y>-size/100)//it was adding also wrong vertices. This line is to solve a bug
{
num[a]=i;
a++;//len of the return list
}
}
}
//create the list with the right vertices
vertex *retlist;
retlist=(vertex*)malloc(sizeof(vertex)*(a+1));
if (retlist==NULL)
{
printf("Can't allocate the memory");
return 0;
}
//the first index is used only as an info container
vertex infos;
infos.index=a+1;
retlist[0]=infos;
//set the value for the return pointer
for(i=1;i<=a;i++)
{
retlist[i]=list[num[i-1]];
}
return retlist;
}
//the function that pass the data to python
void return_funct_1(vertex lower,vertex highter)
{
FILE* ret;
ret=fopen("max_min.txt","w");
if (ret==NULL)
{
printf("Error opening the file\n");
return;
}
fprintf(ret,"%i\n",lower.index);
fprintf(ret,"%i\n",highter.index);
fclose(ret);
}
//the function that pass the data to python
void return_funct_2(vertex *squarelist)
{
FILE* ret;
int i,len;
ret=fopen("square_list.txt","w");
if (ret==NULL)
{
printf("Error opening the file\n");
return;
}
len=squarelist[0].index;
for(i=1;i<len;i++)
{
//return all the informations
//fprintf(ret,"%i %f %f %f\n",squarelist[i].index,squarelist[i].x,squarelist[i].y,squarelist[i].z);
//just return the index(it's enought for the python script)
fprintf(ret,"%i\n",squarelist[i].index);
}
fclose(ret);
}
//argv:
//function[1/2] number_of_vert(int) size_of_square(int) v_index(int) v_xcoord(float) v_ycoord(float) v_zcoord(float)...
//example of file: 2 4 2 0 1 2 3 1 1 2 3 2 1 2 3 3 1 2 3 4 1 2 3 //function 1, number of ver=4, size=2 and then the 4 vertex with their coords
int main(int argc, char *argv[])
{
if(argc==1)
{
printf("%s need a path to a vectorlist file\n",argv[0]);
return 0;
}
FILE* input;
input=fopen(argv[1],"r");
if (input==NULL)
{
printf("Error opening the file\n");
return(0);
}
int func=0,i=0,a=0,u=0;
char read;
char* argument;
argument=(char*)malloc(sizeof(char)*50);//yeah, i know, i should use list instead of an array, but when i first coded this i was quite in hurry (and i'm still learning )
//get the first paramater in the file
argument[0]=fgetc(input);
argument[1]='\0';
func=atoi(argument);
//skipp the space
read=fgetc(input);
//get the number of vertices;
i=0;
do {
read=fgetc(input);
argument[i]=read;
i++;
}while(read!=' ' && !feof(input) );
//set the end of the string
argument[i]='\0';
//set the variable to the correct integer value;
int vnumber=atoi(argument);
i=0;
do {
read=fgetc(input);
argument[i]=read;
i++;
} while(read!=' ' && !feof(input));
//set the end of the string
argument[i]='\0';
float sqsize=atof(argument);
vertex *list;
//allocate memory in the array to fit the number of vertex needed
list=(vertex*)malloc(sizeof(vertex)*vnumber);
//control if the memory get allocated
if (list==NULL)
{
printf("Can't allocate the memory");
return 0;
}
//do the cycle for each vertex
for(u=0;u<vnumber;u++)
{
//read the number and assign it to the proper value of the vertex
for(a=0;a<4;a++)
{
i=0;
do
{
read=fgetc(input);
argument[i]=read;
i++;
} while(read!=' ' && !feof(input));
argument[i]='\0';
if(a==0)
list[u].index=atoi(argument);
if(a==1)
list[u].x=atof(argument);
if(a==2)
list[u].y=atof(argument);
if(a==3)
list[u].z=atof(argument);
}
}
//close the file
fclose(input);
if (func==1)
{
//find the lowest vertex and the higtest vertex
vertex lower;
vertex highter;
vertex *lohi;
lohi=(vertex*)find_vertex(list, vnumber);
lower=lohi[0];
highter=lohi[1];
free(lohi);
return_funct_1(lower,highter);//the function that return the data to python
return 1;
}
if(func==2)
{
//find the list to return
vertex *lohi;
lohi=(vertex*)find_vertex(list, vnumber);
vertex lower;
lower=lohi[0];
free(lohi);
return_funct_2(square_list_of_vertex(list,vnumber, lower, sqsize));//the function that return the data to python
return 1;
}
printf("Function argument was wrong: nothing was done\n");
}
我非常感谢制作这个多线程的任何帮助。处理真正的大数据需要很长时间（今天我尝试了一个 50mb 的文本文件，20 分钟后它只运行了 30 次（在我需要的 26000 上） )，而且由于所有使用它的电脑都至少有 4 个内核，我真的很想让它多线程！谢谢指教！:)
Ps：如果你需要，我也可以发布python脚本代码，但是它充满了对程序内部api的调用，所以我真的不知道它是否有用。