[OpenGL]计算机图形学实验02：多边形世界

/************************************************************************/
/*Test02:			Polygon world
/*Author:			Wang Haiyang
/*Date:				2012/11/20
/*Email:			wanghaiyang@139.me
/************************************************************************/

#define MAX_POLYGONS 8
#define MAX_VERTICES 10
#define EDITRANGE 30

#include <GL/glut.h>
#include <stdlib.h>
#include<iostream>
#include<fstream>
#include <iostream>
#include <string>
using namespace std;

void myMouse(int, int, int, int);
void myMotion(int, int);
void myDisplay();
void myReshape(int, int);
void color_menu(int);
void main_menu(int);
int pick_polygon(int x, int y);
void myInit();

//定义多边形的结构体类型
typedef struct polygon {
int color;                                                //颜色索引
bool used;                                            //如果多边形已经被定义则返回true
int xmin, xmax, ymin, ymax;                //包围盒
float xc, yc;                                            //多边形的中心
int nvertices;                                        //顶点的数目
int x[MAX_VERTICES];                        //顶点
int y[MAX_VERTICES];                        //顶点
} polygon;

//定义标记变量
bool picking = false;                            //是否处于拾取状态
bool moving = false;                            //是否处于移动多边形的状态
int in_polygon = -1;                            //不在任何多边形的内部
int present_color = 0;                        //默认的颜色

int polygonCount = 0;                         //记录一共有多少个多边形

GLfloat  tempArrayX[MAX_VERTICES]={0};
GLfloat  tempArrayY[MAX_VERTICES]={0};
int tempCount = 0;                             //当前绘制的多边形的临时定点数目
bool tempDrawing = false;                      //当前是否在绘制多边形的判断

GLsizei wh = 500;                            //初始化窗口大小
GLsizei ww = 500;                            //初始化窗口大小
int draw_mode = 0;                            //绘制模式

bool editPointing = false;                    //当前是否在编辑顶点

GLfloat colors[8][3] = { { 0.0, 0.0, 0.0 }, { 1.0, 0.0, 0.0 },
{ 0.0, 1.0, 0.0 }, { 0.0, 0.0, 1.0 }, { 0.0, 1.0, 1.0 },
{ 1.0, 0.0, 1.0 }, { 1.0, 1.0, 0.0 }, { 1.0, 1.0, 1.0 } };

polygon polygons[MAX_POLYGONS];

void myReshape(int w, int h) {
glMatrixMode(GL_PROJECTION);
glLoadIdentity();
gluOrtho2D(0.0, (GLdouble) w, 0.0, (GLdouble) h);
glMatrixMode(GL_MODELVIEW);
glLoadIdentity();
glViewport(0, 0, w, h);
ww = w;
wh = h;
}

void myInit() {
glClearColor(0.1, 0.1, 0.5, 1.0);                        //清屏颜色颜色设置为蓝青色
for (int i = 0; i < MAX_POLYGONS; i++) {
polygons[i].used = false;                            //将所有多边形标记为未定义状态
}
}

void myMouse(int btn, int state, int x, int y) {
y = wh - y;

//增加顶点
if (btn == GLUT_LEFT_BUTTON && state == GLUT_DOWN && !picking && !moving&&tempDrawing) {
moving = false;
picking = false;

cout<<"添加了一个顶点！"<<endl;
cout<<"in_polygon："<<in_polygon<<endl;

if (polygons[in_polygon].nvertices == MAX_VERTICES) {
cout << "超出最大顶点数" << endl;
}else{
tempArrayX[tempCount]=x;
tempArrayY[tempCount]=y;
tempCount++;
glutPostRedisplay();
}

if (in_polygon >= 0) {
if (polygons[in_polygon].nvertices == MAX_VERTICES) {
cout << "超出最大顶点数" << endl;
}
else{
int i = polygons[in_polygon].nvertices;
polygons[in_polygon].x[i] = x;
cout<<"添加了一个顶点！polygons[in_polygon].x[i] :"<<polygons[in_polygon].x[i] <<endl;
polygons[in_polygon].y[i] = y;
cout<<"添加了一个顶点！polygons[in_polygon].Y[i] :"<<polygons[in_polygon].y[i] <<endl;
polygons[in_polygon].nvertices++;
}
}
}
if (btn == GLUT_LEFT_BUTTON && state == GLUT_DOWN && picking && !moving) {
moving = false;
picking = false;
int j = pick_polygon(x, y);
if (j >= 0) {
polygons[j].used = false;
polygonCount--;
in_polygon = -1;
glutPostRedisplay();
}
}
}

int pick_polygon(int x, int y) {
for (int i=MAX_POLYGONS; i >=0; i--) {
cout<<"polygons[i].used="<<polygons[i].used<<endl;

if (polygons[i].used) {

if ((x >= polygons[i].xmin) && (x <= polygons[i].xmax)
&& (y >= polygons[i].ymin) && (y <= polygons[i].ymax)) {
in_polygon = i;
moving = true;
return i;
}
}
}
cout << "不在多边形里面" << endl;
return -1;
}

void myMotion(int x, int y) {
float dx, dy;
y = wh - y;
int i, j;

if(editPointing){
for (int i = 0; i < MAX_POLYGONS; ++i) {
if (polygons[i].used) {
for (int j = 0; j < polygons[i].nvertices; ++j) {
if(x<polygons[i].x[j]+EDITRANGE&&x>polygons[i].x[j]-EDITRANGE
&&y<polygons[i].y[j]+EDITRANGE&&y>polygons[i].y[j]-EDITRANGE){
polygons[i].x[j]=x;
polygons[i].y[j]=y;
}
}
}
}
glutPostRedisplay();
}

if(tempDrawing){
tempArrayX[tempCount-1]=x;
tempArrayY[tempCount-1]=y;

glutPostRedisplay();
}

if (moving) {
j = pick_polygon(x, y);
if (j < 0) {
cout << "不在多边形里面" << endl;
return;
}

dx = x - polygons[j].xc;
dy = y - polygons[j].yc;
for (i = 0; i < polygons[j].nvertices; i++) {
polygons[j].x[i] += dx;
polygons[j].y[i] += dy;
}
polygons[j].xc += dx;
polygons[j].yc += dy;

polygons[j].xmax += dx;
polygons[j].xmin += dx;
polygons[j].ymax += dy;
polygons[j].ymin += dy;

glutPostRedisplay();
}
}

void color_menu(int index) {
present_color = index;
if (in_polygon >= 0) {
polygons[in_polygon].color = index;
}
}

void main_menu(int index) {
int i= 0;
switch (index) {
case 1:                                    //    建立一个新的多边形
{
tempDrawing = true;
tempCount = 0;
moving = false;
picking = false;
editPointing=false;
moving = false;
for (i = 0; i < MAX_POLYGONS; i++) {
if (polygons[i].used == false) {
break;
}
}

if (i == MAX_POLYGONS) {
cout << "已经达到最大值\n" << endl;
exit(0);
}
cout << "i=" << i << endl;
polygons[i].color = present_color;
polygons[i].used = true;
polygons[i].nvertices = 0;
in_polygon = i;
picking = false;
break;
}
case 2:                                    //    结束多边形的定义并计算多边形的包围盒和它的中心位置
tempDrawing = false;
tempCount = 0;
moving = false;
picking = false;
editPointing=false;

if (in_polygon >= 0) {
polygons[in_polygon].xmax = polygons[in_polygon].xmin =
polygons[in_polygon].x[0];
polygons[in_polygon].ymax = polygons[in_polygon].ymin =
polygons[in_polygon].y[0];
polygons[in_polygon].xc = polygons[in_polygon].x[0];
polygons[in_polygon].yc = polygons[in_polygon].y[0];
for (int i = 1; i < polygons[in_polygon].nvertices; i++) {
if (polygons[in_polygon].x[i] < polygons[in_polygon].xmin) {
polygons[in_polygon].xmin = polygons[in_polygon].x[i];
} else if (polygons[in_polygon].x[i]
> polygons[in_polygon].xmax) {
polygons[in_polygon].xmax = polygons[in_polygon].x[i];
}
if (polygons[in_polygon].y[i] < polygons[in_polygon].ymin) {
polygons[in_polygon].ymin = polygons[in_polygon].y[i];
} else if (polygons[in_polygon].y[i]
> polygons[in_polygon].ymax) {
polygons[in_polygon].ymax = polygons[in_polygon].y[i];
}
polygons[in_polygon].xc += polygons[in_polygon].x[i];
polygons[in_polygon].yc += polygons[in_polygon].y[i];
cout<<"polygons[in_polygon].x"<<i<<":"<<polygons[in_polygon].x[i]<<endl;
cout<<"polygons[in_polygon].y"<<i<<":"<<polygons[in_polygon].y[i]<<endl;
}
polygons[in_polygon].xc = polygons[in_polygon].xc
/ polygons[in_polygon].nvertices;
polygons[in_polygon].yc = polygons[in_polygon].yc
/ polygons[in_polygon].nvertices;
}
in_polygon = -1;
polygonCount++;
glutPostRedisplay();
break;

case 3:                                    //    设立拾取模式
tempDrawing = false;
tempCount = 0;
moving = false;
picking = true;
editPointing=false;
break;

case 4:                            //是否移动
tempDrawing = false;
tempCount = 0;
moving = true;
picking = false;
editPointing=false;
break;

case 5:                        //存储文件
{
tempDrawing = false;
tempCount = 0;
moving = false;
picking = false;
editPointing=false;
in_polygon=-1;

std::ofstream file("Polygon.dat",std::ios::ate|std::ios::binary);
if(!file)
{
std::cout<<"文件打开失败!";
abort();//等同于exit
}
//写文件
for(int i=0;i<MAX_POLYGONS;i++){
cout<<"polygons["<<i<<"].used"<<polygons[i].used<<endl;
if(polygons[i].used){
cout<<"我写了一个！！"<<endl;
file.write((char*) &polygons[i],sizeof(polygons[i]));
cout<<"&polygons[i],sizeof(polygons[i])"<<&polygons[i]<<"size"<<sizeof(polygons[i])<<endl;
}
}
//关闭文件
file.close();
break;
}
case 6:                            //读取文件
{
in_polygon=-1;
tempDrawing = false;
tempCount = 0;
moving = false;
picking = false;
editPointing=false;

std::ifstream rfile("Polygon.dat",std::ios::binary);
//打开文件
//std::ofstream file("Polygon.dat",std::ios::ate|std::ios::binary);
if(!rfile)
{
std::cout<<"文件打开失败!";
return ;//等同于exit
}

//读文件
for(int i=0;i<MAX_POLYGONS;i++)
{
cout<<"polygons["<<i<<"].used"<<polygons[i].used<<endl;
rfile.read((char*) &polygons[i],sizeof(polygons[i]));
cout<<"polygons["<<i<<"].used"<<polygons[i].used<<endl;
}

glutPostRedisplay();
//关闭文件
rfile.close();
break;
}
case 7:
in_polygon=-1;
tempDrawing = false;
tempCount = 0;
moving = false;
picking = false;
editPointing = true ;
break;
}

}

void myDisplay() {
cout<<"myDisplay!"<<endl;
glClear(GL_COLOR_BUFFER_BIT);

for (int i = 0; i < MAX_POLYGONS; ++i) {
if (polygons[i].used&&(i!=in_polygon||moving)) {
cout<<"polygons[i].used="<<polygons[i].used<<endl;
glColor3fv(colors[polygons[i].color]);
cout<<colors[polygons[i].color]<<endl;
glBegin(GL_POLYGON);
for (int j = 0; j < polygons[i].nvertices; ++j) {
glVertex2i(polygons[i].x[j], polygons[i].y[j]);
cout<<"X:"<<polygons[i].x[j]<< "Y:"<<polygons[i].y[j]<<endl;
}
glEnd();
}
}

if(tempDrawing){
glColor3fv(colors[present_color]);
glBegin(GL_LINE_STRIP);
for (int j = 0; j <tempCount; ++j) {
glVertex2f(tempArrayX[j],tempArrayY[j]);
}
glEnd();
}

glFlush();
}

int main(int argc, char **argv) {

int c_menu;
glutInit(&argc, argv);
glutInitDisplayMode(GLUT_SINGLE | GLUT_RGB);
glutInitWindowPosition(400, 100);
glutInitWindowSize(500, 500);
glutCreateWindow("Polygon Test");
glutDisplayFunc(myDisplay);
myInit();
c_menu = glutCreateMenu(color_menu);

glutAddMenuEntry("黑色", 0);
glutAddMenuEntry("红色", 1);
glutAddMenuEntry("绿色", 2);
glutAddMenuEntry("蓝色", 3);
glutAddMenuEntry("青色", 4);
glutAddMenuEntry("紫色", 5);
glutAddMenuEntry("黄色", 6);
glutAddMenuEntry("白色", 7);

glutCreateMenu(main_menu);
glutAddMenuEntry("新建多边形", 1);
glutAddMenuEntry("结束新建", 2);
glutAddMenuEntry("删除", 3);
glutAddMenuEntry("移动", 4);
glutAddMenuEntry("存档本地文件", 5);//将四边形数据存储到本地文件的选项
glutAddMenuEntry("读取本地文件", 6);
glutAddMenuEntry("编辑顶点", 7);
glutAddSubMenu("颜色", c_menu);
cout <<"c_menu="<< c_menu << endl;
glutAttachMenu(GLUT_RIGHT_BUTTON);
glutReshapeFunc(myReshape);
glutMouseFunc(myMouse);
glutMotionFunc(myMotion);

glutMainLoop();
}