// first_3D.cpp : 定义控制台应用程序的入口点。

 //

 #include "stdafx.h"

 #include <GL/glut.h>

 #include <math.h>

 // 将立方体的八个顶点保存到一个数组里面

 static const GLfloat vertex_list[][] = {

     -0.5f, -0.5f, -0.5f,

      0.5f, -0.5f, -0.5f,

     -0.5f,  0.5f, -0.5f,

      0.5f,  0.5f, -0.5f,

     -0.5f, -0.5f,  0.5f,

      0.5f, -0.5f,  0.5f,

     -0.5f,  0.5f,  0.5f,

      0.5f,  0.5f,  0.5f,

 };

 //变换后数组

 GLfloat vertex_list_new[][] = {

     -0.5f, -0.5f, -0.5f,

      0.5f, -0.5f, -0.5f,

     -0.5f,  0.5f, -0.5f,

      0.5f,  0.5f, -0.5f,

     -0.5f, -0.5f,  0.5f,

      0.5f, -0.5f,  0.5f,

     -0.5f,  0.5f,  0.5f,

      0.5f,  0.5f,  0.5f,

 };

 void work(float T[][])

 {

     GLfloat list_temp[][];

     for(int i=;i<;i++)

         for(int j=;j<;j++)

             list_temp[i][j] = vertex_list_new[i][j];

     for(int i=;i<;i++)

     {

         for(int j=;j<;j++)

         {

             float sum = ;

             for(int k=;k<;k++)

             {

                 sum+=list_temp[i][k]*T[k][j];

             }

             vertex_list_new[i][j] = sum;

         }

     }

     return;

 }

 // 将要使用的顶点的序号保存到一个数组里面

 static const GLint index_list[][] = {

     , , , ,

     , , , ,

     , , , ,

     , , , ,

     , , , ,

     , , , ,

 };

 void display()

 {

     glClear(GL_COLOR_BUFFER_BIT);

     glMatrixMode(GL_MODELVIEW);

     glLoadIdentity();

     //gluLookAt(1.5,1.0,1.0,0.0,0.0,0.0,0.0,1.0,0.0);//视点

     /* /坐标轴

     glLineWidth(1);

     glColor3f( 0.0, 0.0, 0.0);     // 黑色

     glBegin(GL_LINES);

     glVertex3f(-0xFFFFFFF,0,0);

     glVertex3f(0xFFFFFFF,0,0);

     glVertex3f(0,-0xFFFFFFF,0);

     glVertex3f(0,0xFFFFFFF,0);

     glVertex3f(0,0,-0xFFFFFFF);

     glVertex3f(0,0,0xFFFFFFF);

     glEnd();

     //坐标轴绘制结束*/

     /* /绘制原立方体

     glColor3f( 1.0, 1.0, 0.0);

     //glBegin(GL_QUADS);

     for(int i=0; i<6; ++i)         // 有六个面，循环六次

     {

         glBegin( GL_LINE_LOOP);

         for(int j=0; j<4; ++j)     // 每个面有四个顶点，循环四次

         {

             glVertex3fv(vertex_list[index_list[i][j]]);

         }

         glEnd();

     }

     //立方体绘制结束*/

     //绘制新立方体

     glColor3f( 1.0, 0.0, 0.0);

     //glBegin(GL_QUADS);

     for(int i=; i<; ++i)         // 有六个面，循环六次

     {

         glBegin( GL_LINE_LOOP);

         for(int j=; j<; ++j)     // 每个面有四个顶点，循环四次

         {

             glVertex3fv(vertex_list_new[index_list[i][j]]);

         }

         glEnd();

     }

     //立方体绘制结束

     glFlush();

     glutSwapBuffers();

 }

 void reshape(int w,int h)

 {

     glViewport(,,w,h);

     glMatrixMode(GL_PROJECTION);

     glLoadIdentity();

     glOrtho(-1.0,1.0,-1.0,1.0,-1.0,1.0);

 } 

 void init()

 {

     glClearColor( , , , 0.0);

     glMatrixMode(GL_PROJECTION);

     glLoadIdentity();

     //glOrtho(-4.0,4.0,-4.0,4.0,-4.0,4.0);

     glMatrixMode(GL_MODELVIEW);

 }

 int main(int argc,char** argv)

 {

     //计算部分

     float a,b,c;//Ov

     a = ;

     b = ;

     c = ;

     float R = sqrt(a*a+b*b+c*c);

     float d = 1.0;

     float costh = c/sqrt(a*a+c*c);

     float sinth = a/sqrt(a*a+c*c);

     float cosfy = b/R;

     float sinfy = sqrt(a*a+c*c)/R;

     float T1[][] = {{,,,},{,,,},{,,,},{-a,-b,-c,}};                    //原点到视点平移变换矩阵

     float T2[][] = {{-costh,,-sinth,},{,,,},{sinth,,-costh,},{,,,}};    //绕y1轴旋转变换

     float T3[][] = {{,,,},{,sinfy,-cosfy,},{,cosfy,sinfy,},{,,,}};      //绕x2轴旋转变换

     float T4[][] = {{-,,,},{,,,},{,,,},{,,,}};                      //关于y3Ovz3面的反射变换

     //work(T1);work(T2);work(T3);work(T4);

     //世界--观察坐标系 合成矩阵

     float Tv[][] = {{cosfy,-cosfy*sinth,-sinfy*sinth,},{,sinfy,-cosfy,},{-sinth,-cosfy*costh,-sinfy*costh,},{,,R,}};

     //work(Tv);

     float Tpersp[][] = {{,,,},{,,,},{,,,/d},{,,,}}; //透视矩阵

     float Tproj[][] = {{-,,,},{,,,},{,,,},{,,,}};   //投影矩阵

     //work(Tpersp);work(Tproj);

     float Ts[][] = {{,,,},{,,,},{,,,/d},{,,,}};     //合成

     //work(Ts);

     //总合成

     float T[][] = {{costh,-costh*sinth,,-sinfy*sinth/d},{,sinfy,,-cosfy/d},{-sinth,-cosfy*costh,,-sinfy*costh/d},{,,,R/d}};

     work(T);

     float T_1[][] = {{,,,},{,,,},{,,,-/d},{,,,R/d}};

     //work(T_1);

     glutInit(&argc,argv);

     glutInitDisplayMode(GLUT_DOUBLE | GLUT_RGB);

     glutInitWindowSize(,);

     glutInitWindowPosition(,);

     glutCreateWindow("立方体");

     glutReshapeFunc(reshape);

     glutDisplayFunc(display);

     init();

     glutMainLoop();

     return ;

 }