Lm's圖學筆記week17

• step 01 
• 先做一個茶壺

#include <GL/glut.h>
void display(){
    glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
        glutSolidTeapot( 0.3 );
    glutSwapBuffers();
}
int main( int argc, char ** argv )
{
    glutInit( &argc, argv);
    glutInitDisplayMode(GLUT_DOUBLE|GLUT_DEPTH);
    glutCreateWindow("week17 review");

    glutDisplayFunc(display);
    glutMainLoop();
}

• 放大視窗(預設300x300)

        移動視窗(預設會照著前一個位置往下移一點點)

glutInitWindowSize(500,500);  //正方形圖形才不會變形
glutInitWindowPosition(700,0);

• 色彩: glClearColor() glColor3f()

void display(){
    glClearColor( 1,0,0,0);///用來Clear的Color 用紅色
    glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
        glColor3f( 1,1,0 );
        glutSolidTeapot( 0.3 );
    glutSwapBuffers();
}

#include <GL/glut.h>
void display(){
    glClearColor( 1,0,0,0);///用來Clear的Color 用紅色
    glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
        glColor3f( 1,1,0 );
        glutSolidTeapot( 0.3 );
    glutSwapBuffers();
}
int main( int argc, char ** argv )
{
    glutInit( &argc, argv);
    glutInitWindowSize(500,500);
    glutInitWindowPosition(700,200);
    glutInitDisplayMode(GLUT_DOUBLE|GLUT_DEPTH);
    glutCreateWindow("week17 review");

    glutDisplayFunc(display);
    glutMainLoop();
}

• 打光試看看(可從 GLUT 範例拿來用)

          打光陣列

const GLfloat light_ambient[]  = { 0.0f, 0.0f, 0.0f, 1.0f };
const GLfloat light_diffuse[]  = { 1.0f, 1.0f, 1.0f, 1.0f };
const GLfloat light_specular[] = { 1.0f, 1.0f, 1.0f, 1.0f };
const GLfloat light_position[] = { 2.0f, 5.0f, 5.0f, 0.0f };///+5會背光

const GLfloat mat_ambient[]    = { 0.7f, 0.7f, 0.7f, 1.0f };
const GLfloat mat_diffuse[]    = { 0.8f, 0.8f, 0.8f, 1.0f };
const GLfloat mat_specular[]   = { 1.0f, 1.0f, 1.0f, 1.0f };
const GLfloat high_shininess[] = { 100.0f };

      同時要有打光的函式, 在 main()呼叫

    glEnable(GL_DEPTH_TEST);
    glDepthFunc(GL_LESS);

    glEnable(GL_LIGHT0);
    glEnable(GL_NORMALIZE);
    glEnable(GL_COLOR_MATERIAL);
    glEnable(GL_LIGHTING);

    glLightfv(GL_LIGHT0, GL_AMBIENT,  light_ambient);
    glLightfv(GL_LIGHT0, GL_DIFFUSE,  light_diffuse);
    glLightfv(GL_LIGHT0, GL_SPECULAR, light_specular);
    glLightfv(GL_LIGHT0, GL_POSITION, light_position);

    glMaterialfv(GL_FRONT, GL_AMBIENT,   mat_ambient);
    glMaterialfv(GL_FRONT, GL_DIFFUSE,   mat_diffuse);
    glMaterialfv(GL_FRONT, GL_SPECULAR,  mat_specular);
    glMaterialfv(GL_FRONT, GL_SHININESS, high_shininess);




• 整合上面

#include <GL/glut.h>

void display(){
    glClearColor( 1,0,0,0);///用來Clear的Color 用紅色
    glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
        glColor3f( 1,1,0 );
        glutSolidTeapot( 0.3 );
    glutSwapBuffers();
}
const GLfloat light_ambient[]  = { 0.0f, 0.0f, 0.0f, 1.0f };
const GLfloat light_diffuse[]  = { 1.0f, 1.0f, 1.0f, 1.0f };
const GLfloat light_specular[] = { 1.0f, 1.0f, 1.0f, 1.0f };
const GLfloat light_position[] = { 2.0f, 5.0f, -5.0f, 0.0f };///改成-5會變正面的光

const GLfloat mat_ambient[]    = { 0.7f, 0.7f, 0.7f, 1.0f };
const GLfloat mat_diffuse[]    = { 0.8f, 0.8f, 0.8f, 1.0f };
const GLfloat mat_specular[]   = { 1.0f, 1.0f, 1.0f, 1.0f };
const GLfloat high_shininess[] = { 100.0f };
int main( int argc, char ** argv )
{
    glutInit( &argc, argv);
    glutInitWindowSize(300,300);
    glutInitWindowPosition(700,200);
    glutInitDisplayMode(GLUT_DOUBLE|GLUT_DEPTH);
    glutCreateWindow("week17 review");

    glutDisplayFunc(display);

    glEnable(GL_DEPTH_TEST);
    glDepthFunc(GL_LESS);

    glEnable(GL_LIGHT0);
    glEnable(GL_NORMALIZE);
    glEnable(GL_COLOR_MATERIAL);
    glEnable(GL_LIGHTING);

    glLightfv(GL_LIGHT0, GL_AMBIENT,  light_ambient);
    glLightfv(GL_LIGHT0, GL_DIFFUSE,  light_diffuse);
    glLightfv(GL_LIGHT0, GL_SPECULAR, light_specular);
    glLightfv(GL_LIGHT0, GL_POSITION, light_position);

    glMaterialfv(GL_FRONT, GL_AMBIENT,   mat_ambient);
    glMaterialfv(GL_FRONT, GL_DIFFUSE,   mat_diffuse);
    glMaterialfv(GL_FRONT, GL_SPECULAR,  mat_specular);
    glMaterialfv(GL_FRONT, GL_SHININESS, high_shininess);

    glutMainLoop();
}

解決 T-R-T的問題
        先把身體註解掉,T-R-T只留下最下面的T
void display(){
    glClearColor( 1,0,0,0);///用來Clear的Color 用紅色
    glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
    glPushMatrix();
        glColor3f( 1,1,0 );
        //glutSolidTeapot( 0.3 );///身體先註解掉身體,只看手臂
        glPushMatrix();
            //glTranslatef();///(3)再把轉動中的手臂,掛到肩上
            //glRotatef();///(2)再轉動它
            glTranslatef(-.3, .1, 0);///(1)移動旋轉中心,放正中心
            glutSolidTeapot(0.3);///左手臂
        glPopMatrix();
    glPopMatrix();
    glutSwapBuffers();
}
再把 R弄好, 再把 T 及身體都放出來
float angle=90;
void display(){
    glClearColor( 1,0,0,0);///用來Clear的Color 用紅色
    glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
    glPushMatrix();
        glColor3f( 1,1,0 );
        glutSolidTeapot( 0.3 );///身體先註解掉身體,只看手臂
        glPushMatrix();
            glTranslatef(-.3, 0, 0);///(3)再把轉動中的手臂,掛到肩上
            glRotatef(angle, 0,0,1);///(2)再轉動它
            glTranslatef(-.3, .1, 0);///(1)移動旋轉中心,放正中心
            glutSolidTeapot(0.3);///左手臂
        glPopMatrix();
    glPopMatrix();
    glutSwapBuffers();
}
接下來要用 mouse motion 讓它可以轉起來
float oldX=0;
void mouse(int button, int state, int x, int y){
    oldX = x;
}
void motoin( int x, int y ){
    angle += x-oldX;
    oldX = x;//小心,不要漏掉了
    glutPostRedisplay();///重畫畫面
}
int main( int argc, char ** argv )
{
    glutInit( &argc, argv);
    glutInitWindowSize(300,300);
    glutInitWindowPosition(700,200);
    glutInitDisplayMode(GLUT_DOUBLE|GLUT_DEPTH);
    glutCreateWindow("week17 review");

    glutMouseFunc(mouse);
    glutMotionFunc(motion);
    glutDisplayFunc(display);
    //...
}
step02 用 mouse() motion() 讓關節動起來
#include <GL/glut.h>
float angle=90;
float oldX=0;
void mouse(int button, int state, int x, int y){
    oldX = x;
}
void motion( int x, int y ){
    angle += x-oldX;
    oldX = x;
    glutPostRedisplay(); ///重畫畫面
}
void display(){
    glClearColor( 1,0,0,0);///用來Clear的Color 用紅色
    glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
    glPushMatrix();
        glColor3f( 1,1,0 );
        glutSolidTeapot( 0.3 );///身體先註解掉身體,只看手臂
        glPushMatrix();
            glTranslatef(-.3, 0, 0);///(3)再把轉動中的手臂,掛到肩上
            glRotatef(angle, 0,0,1);///(2)再轉動它
            glTranslatef(-.3, .1, 0);///(1)移動旋轉中心,放正中心
            glutSolidTeapot(0.3);///左手臂
        glPopMatrix();
    glPopMatrix();
    glutSwapBuffers();
}
const GLfloat light_ambient[]  = { 0.0f, 0.0f, 0.0f, 1.0f };
const GLfloat light_diffuse[]  = { 1.0f, 1.0f, 1.0f, 1.0f };
const GLfloat light_specular[] = { 1.0f, 1.0f, 1.0f, 1.0f };
const GLfloat light_position[] = { 2.0f, 5.0f, -5.0f, 0.0f };

const GLfloat mat_ambient[]    = { 0.7f, 0.7f, 0.7f, 1.0f };
const GLfloat mat_diffuse[]    = { 0.8f, 0.8f, 0.8f, 1.0f };
const GLfloat mat_specular[]   = { 1.0f, 1.0f, 1.0f, 1.0f };
const GLfloat high_shininess[] = { 100.0f };
int main( int argc, char ** argv )
{
    glutInit( &argc, argv);
    glutInitWindowSize(300,300);
    glutInitWindowPosition(700,200);
    glutInitDisplayMode(GLUT_DOUBLE|GLUT_DEPTH);
    glutCreateWindow("week17 review");

    glutMouseFunc(mouse);
    glutMotionFunc(motion);
    glutDisplayFunc(display);

    glEnable(GL_DEPTH_TEST);
    glDepthFunc(GL_LESS);

    glEnable(GL_LIGHT0);
    glEnable(GL_NORMALIZE);
    glEnable(GL_COLOR_MATERIAL);
    glEnable(GL_LIGHTING);

    glLightfv(GL_LIGHT0, GL_AMBIENT,  light_ambient);
    glLightfv(GL_LIGHT0, GL_DIFFUSE,  light_diffuse);
    glLightfv(GL_LIGHT0, GL_SPECULAR, light_specular);
    glLightfv(GL_LIGHT0, GL_POSITION, light_position);

    glMaterialfv(GL_FRONT, GL_AMBIENT,   mat_ambient);
    glMaterialfv(GL_FRONT, GL_DIFFUSE,   mat_diffuse);
    glMaterialfv(GL_FRONT, GL_SPECULAR,  mat_specular);
    glMaterialfv(GL_FRONT, GL_SHININESS, high_shininess);

    glutMainLoop();
}
Step03 keyboard() 可切換關節 & 存檔讀檔
float angle[20]={};///先都設成0
int angleID=0;///現在要動的關節是誰?
void keyboard(unsigned char key, int x, int y){
    if(key=='0') angleID=0;
    if(key=='1') angleID=1;
    if(key=='2') angleID=2;
    if(key=='3') angleID=3;
    if(key=='4') angleID=4;
    if(key=='5') angleID=5;
    if(key=='6') angleID=6;
}///如果關節很多, 可能要用迴圈來讓程式只要2行 for(int i=0; i<10; i++)
///可能也要用到英文字母
int main( int argc, char ** argv )
{
    glutInit( &argc, argv);
    glutInitWindowSize(300,300);
    glutInitWindowPosition(700,200);
    glutInitDisplayMode(GLUT_DOUBLE|GLUT_DEPTH);
    glutCreateWindow("week17 review");

    glutKeyboardFunc(keyboard);//要有這行, 註冊 keyboard()
    glutMouseFunc(mouse);
    glutMotionFunc(motion);
    glutDisplayFunc(display);
void motion( int x, int y ){
    angle[angleID] += x-oldX;///0: angle[0], 1: angle[1]..
    oldX = x;
    glutPostRedisplay();///重畫畫面
}
void display(){
    glClearColor( 1,0,0,0);///用來Clear的Color 用紅色
    glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
    glPushMatrix();
        glColor3f( 1,1,0 );
        glutSolidTeapot( 0.3 );///身體先註解掉身體,只看手臂
        glPushMatrix();
            glTranslatef(-.3, 0, 0);///(3)再把轉動中的手臂,掛到肩上
            glRotatef(angle[0], 0,0,1);///(2)再轉動它
            glTranslatef(-.3, .1, 0);///(1)移動旋轉中心,放正中心
            glutSolidTeapot(0.3);///左手臂
            glPushMatrix();
                glTranslatef(-.3, 0, 0);///(3)再把轉動中的手臂,掛到肩上
                glRotatef(angle[1], 0,0,1);///(2)再轉動它
                glTranslatef(-.3, 0, 0);///(1)移動旋轉中心,放正中心
                glutSolidTeapot(0.3);///左手肘
            glPopMatrix();
        glPopMatrix();
    glPopMatrix();
    glutSwapBuffers();
}
右半邊,也照著做出來
void display(){
    glClearColor( 1,0,0,0);///用來Clear的Color 用紅色
    glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
    glPushMatrix();
        glColor3f( 1,1,0 );
        glutSolidTeapot( 0.3 );///身體先註解掉身體,只看手臂
        glPushMatrix();///左半邊
            glTranslatef(-.3, 0, 0);///(3)再把轉動中的手臂,掛到肩上
            glRotatef(angle[0], 0,0,1);///(2)再轉動它
            glTranslatef(-.3, .1, 0);///(1)移動旋轉中心,放正中心
            glutSolidTeapot(0.3);///左手臂
            glPushMatrix();
                glTranslatef(-.3, 0, 0);///(3)再把轉動中的手臂,掛到肩上
                glRotatef(angle[1], 0,0,1);///(2)再轉動它
                glTranslatef(-.3, 0, 0);///(1)移動旋轉中心,放正中心
                glutSolidTeapot(0.3);///左手肘
            glPopMatrix();
        glPopMatrix();
        glPushMatrix();///右半邊
            glTranslatef(+.3, 0, 0);///(3)再把轉動中的手臂,掛到肩上
            glRotatef(angle[2], 0,0,1);///(2)再轉動它
            glTranslatef(+.3, .1, 0);///(1)移動旋轉中心,放正中心
            glutSolidTeapot(0.3);///右手臂
            glPushMatrix();
                glTranslatef(+.3, 0, 0);///(3)再把轉動中的手臂,掛到肩上
                glRotatef(angle[3], 0,0,1);///(2)再轉動它
                glTranslatef(+.3, 0, 0);///(1)移動旋轉中心,放正中心
                glutSolidTeapot(0.3);///右手肘
            glPopMatrix();
        glPopMatrix();
    glPopMatrix();
    glutSwapBuffers();
}
step04 存檔、讀檔
#include <stdio.h>
FILE * fout = NULL;
FILE * fin = NULL;
void keyboard(unsigned char key, int x, int y){
    if(key=='0') angleID=0;
    if(key=='1') angleID=1;
    if(key=='2') angleID=2;
    if(key=='3') angleID=3;
    if(key=='4') angleID=4;
    if(key=='5') angleID=5;
    if(key=='6') angleID=6;
    if(key=='s'){///存檔
        if( fout==NULL ) fout = fopen("angle.txt", "w+");
        for(int i=0; i<20; i++) fprintf(fout, "%.2f ", angle[i]);
        fprintf(fout, "\n");
        printf("save angle.txt\n");
    }else if(key=='r'){///讀檔 (不能和存檔同時做,因angle.txt不能開2次)
        if( fin==NULL ) fin = fopen("angle.txt", "r");
        for(int i=0; i<20; i++) fscanf(fin, "%f", &angle[i]);
        glutPostRedisplay();///重畫畫面
        printf("read angle.txt\n");
    }
}
完整程式
#include <GL/glut.h>
#include <stdio.h>
FILE * fout = NULL;
FILE * fin = NULL;
float angle[20]={};///先都設成0
int angleID=0;///現在要動的關節是誰?
void keyboard(unsigned char key, int x, int y){
    if(key=='0') angleID=0;
    if(key=='1') angleID=1;
    if(key=='2') angleID=2;
    if(key=='3') angleID=3;
    if(key=='4') angleID=4;
    if(key=='5') angleID=5;
    if(key=='6') angleID=6;
    if(key=='s'){///存檔
        if( fout==NULL ) fout = fopen("angle.txt", "w+");
        for(int i=0; i<20; i++) fprintf(fout, "%.2f ", angle[i]);
        fprintf(fout, "\n");
        printf("save angle.txt\n");
    }else if(key=='r'){///讀檔 (不能和存檔同時做,因angle.txt不能開2次)
        if( fin==NULL ) fin = fopen("angle.txt", "r");
        for(int i=0; i<20; i++) fscanf(fin, "%f", &angle[i]);
        glutPostRedisplay();///重畫畫面
        printf("read angle.txt\n");
    }
}///如果關節很多, 可能要用迴圈來讓程式只要2行 for(int i=0; i<10; i++)
///可能也要用到英文字母
float oldX=0;
void mouse(int button, int state, int x, int y){
    oldX = x;
}
void motion( int x, int y ){
    angle[angleID] += x-oldX;///0: angle[0], 1: angle[1]..
    oldX = x;
    glutPostRedisplay();///重畫畫面
}
void display(){
    glClearColor( 1,0,0,0);///用來Clear的Color 用紅色
    glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
    glPushMatrix();
        glColor3f( 1,1,0 );
        glutSolidTeapot( 0.3 );///身體先註解掉身體,只看手臂
        glPushMatrix();///左半邊
            glTranslatef(-.3, 0, 0);///(3)再把轉動中的手臂,掛到肩上
            glRotatef(angle[0], 0,0,1);///(2)再轉動它
            glTranslatef(-.3, .1, 0);///(1)移動旋轉中心,放正中心
            glutSolidTeapot(0.3);///左手臂
            glPushMatrix();
                glTranslatef(-.3, 0, 0);///(3)再把轉動中的手臂,掛到肩上
                glRotatef(angle[1], 0,0,1);///(2)再轉動它
                glTranslatef(-.3, 0, 0);///(1)移動旋轉中心,放正中心
                glutSolidTeapot(0.3);///左手肘
            glPopMatrix();
        glPopMatrix();
        glPushMatrix();///右半邊
            glTranslatef(+.3, 0, 0);///(3)再把轉動中的手臂,掛到肩上
            glRotatef(angle[2], 0,0,1);///(2)再轉動它
            glTranslatef(+.3, .1, 0);///(1)移動旋轉中心,放正中心
            glutSolidTeapot(0.3);///右手臂
            glPushMatrix();
                glTranslatef(+.3, 0, 0);///(3)再把轉動中的手臂,掛到肩上
                glRotatef(angle[3], 0,0,1);///(2)再轉動它
                glTranslatef(+.3, 0, 0);///(1)移動旋轉中心,放正中心
                glutSolidTeapot(0.3);///右手肘
            glPopMatrix();
        glPopMatrix();
    glPopMatrix();
    glutSwapBuffers();
}
const GLfloat light_ambient[]  = { 0.0f, 0.0f, 0.0f, 1.0f };
const GLfloat light_diffuse[]  = { 1.0f, 1.0f, 1.0f, 1.0f };
const GLfloat light_specular[] = { 1.0f, 1.0f, 1.0f, 1.0f };
const GLfloat light_position[] = { 2.0f, 5.0f, -5.0f, 0.0f };

const GLfloat mat_ambient[]    = { 0.7f, 0.7f, 0.7f, 1.0f };
const GLfloat mat_diffuse[]    = { 0.8f, 0.8f, 0.8f, 1.0f };
const GLfloat mat_specular[]   = { 1.0f, 1.0f, 1.0f, 1.0f };
const GLfloat high_shininess[] = { 100.0f };
int main( int argc, char ** argv )
{
    glutInit( &argc, argv);
    glutInitWindowSize(300,300);
    glutInitWindowPosition(700,200);
    glutInitDisplayMode(GLUT_DOUBLE|GLUT_DEPTH);
    glutCreateWindow("week17 review");

    glutKeyboardFunc(keyboard);
    glutMouseFunc(mouse);
    glutMotionFunc(motion);
    glutDisplayFunc(display);

    glEnable(GL_DEPTH_TEST);
    glDepthFunc(GL_LESS);

    glEnable(GL_LIGHT0);
    glEnable(GL_NORMALIZE);
    glEnable(GL_COLOR_MATERIAL);
    glEnable(GL_LIGHTING);

    glLightfv(GL_LIGHT0, GL_AMBIENT,  light_ambient);
    glLightfv(GL_LIGHT0, GL_DIFFUSE,  light_diffuse);
    glLightfv(GL_LIGHT0, GL_SPECULAR, light_specular);
    glLightfv(GL_LIGHT0, GL_POSITION, light_position);

    glMaterialfv(GL_FRONT, GL_AMBIENT,   mat_ambient);
    glMaterialfv(GL_FRONT, GL_DIFFUSE,   mat_diffuse);
    glMaterialfv(GL_FRONT, GL_SPECULAR,  mat_specular);
    glMaterialfv(GL_FRONT, GL_SHININESS, high_shininess);

    glutMainLoop();
}
step05 要做動畫、內插
void timer(int t){
    glutTimerFunc( 500, timer, t+1);
    if( fin==NULL ) fin = fopen("angle.txt", "r");
    for(int i=0; i<20; i++) fscanf(fin, "%f", &angle[i]);
    glutPostRedisplay();///重畫畫面
    printf("read angle.txt\n");
}
void keyboard(unsigned char key, int x, int y){
    if(key=='0') angleID=0;
    if(key=='1') angleID=1;
    if(key=='2') angleID=2;
    if(key=='3') angleID=3;
    if(key=='4') angleID=4;
    if(key=='5') angleID=5;
    if(key=='6') angleID=6;
    if(key=='p'){///Play播放
        glutTimerFunc(0, timer, 0);///一開始的第1個timer
    }
它就會開始動囉!!!
但是, 想要動得更順, 利用 alpha 來內插
#include <GL/glut.h>
#include <stdio.h>
FILE * fout = NULL;
FILE * fin = NULL;
float angle[20]={}, angleOld[20], angleNew[20];///先都設成0
int angleID=0;///現在要動的關節是誰?
void timer(int t){
    glutTimerFunc( 50, timer, t+1);
    if(t%10==0){
        for(int i=0; i<20; i++) angleOld[i] = angleNew[i];

        if( fin==NULL ) fin = fopen("angle.txt", "r");
        for(int i=0; i<20; i++) fscanf(fin, "%f", &angleNew[i]);
        printf("read angle.txt\n");
    }
    float alpha = (t%10)/10.0;///介於 0.0 - 1.0 之間
    for(int i=0; i<20; i++) angle[i] = alpha*angleNew[i]+(1-alpha)*angleOld[i];
    glutPostRedisplay();///重畫畫面
}
全部的程式碼
#include <GL/glut.h>
#include <stdio.h>
FILE * fout = NULL;
FILE * fin = NULL;
float angle[20]={}, angleOld[20], angleNew[20];///先都設成0
int angleID=0;///現在要動的關節是誰?
void timer(int t){
    glutTimerFunc( 20, timer, t+1);
    if(t%25==0){
        for(int i=0; i<20; i++) angleOld[i] = angleNew[i];

        if( fin==NULL ) fin = fopen("angle.txt", "r");
        for(int i=0; i<20; i++) fscanf(fin, "%f", &angleNew[i]);
        printf("read angle.txt\n");
    }
    float alpha = (t%25)/25.0;///介於 0.0 舊 - 1.0 新 之間 (請代入 0, 0.5, 1 觀察)
    for(int i=0; i<20; i++) angle[i] = alpha*angleNew[i]+(1-alpha)*angleOld[i];
    glutPostRedisplay();///重畫畫面
}
void keyboard(unsigned char key, int x, int y){
    if(key=='0') angleID=0;
    if(key=='1') angleID=1;
    if(key=='2') angleID=2;
    if(key=='3') angleID=3;
    if(key=='4') angleID=4;
    if(key=='5') angleID=5;
    if(key=='6') angleID=6;
    if(key=='p'){///Play播放
        glutTimerFunc(0, timer, 0);///一開始的第1個timer
    }
    if(key=='s'){///存檔
        if( fout==NULL ) fout = fopen("angle.txt", "w+");
        for(int i=0; i<20; i++) fprintf(fout, "%.2f ", angle[i]);
        fprintf(fout, "\n");
        printf("save angle.txt\n");
    }else if(key=='r'){///讀檔 (不能和存檔同時做,因angle.txt不能開2次)
        if( fin==NULL ) fin = fopen("angle.txt", "r");
        for(int i=0; i<20; i++) fscanf(fin, "%f", &angle[i]);
        glutPostRedisplay();///重畫畫面
        printf("read angle.txt\n");
    }
}///如果關節很多, 可能要用迴圈來讓程式只要2行 for(int i=0; i<10; i++)
///可能也要用到英文字母
float oldX=0;
void mouse(int button, int state, int x, int y){
    oldX = x;
}
void motion( int x, int y ){
    angle[angleID] += x-oldX;///0: angle[0], 1: angle[1]..
    oldX = x;
    glutPostRedisplay();///重畫畫面
}
void display(){
    glClearColor( 1,0,0,0);///用來Clear的Color 用紅色
    glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
    glPushMatrix();
        glColor3f( 1,1,0 );
        glutSolidTeapot( 0.3 );///身體先註解掉身體,只看手臂
        glPushMatrix();///左半邊
            glTranslatef(-.3, 0, 0);///(3)再把轉動中的手臂,掛到肩上
            glRotatef(angle[0], 0,0,1);///(2)再轉動它
            glTranslatef(-.3, .1, 0);///(1)移動旋轉中心,放正中心
            glutSolidTeapot(0.3);///左手臂
            glPushMatrix();
                glTranslatef(-.3, 0, 0);///(3)再把轉動中的手臂,掛到肩上
                glRotatef(angle[1], 0,0,1);///(2)再轉動它
                glTranslatef(-.3, 0, 0);///(1)移動旋轉中心,放正中心
                glutSolidTeapot(0.3);///左手肘
            glPopMatrix();
        glPopMatrix();
        glPushMatrix();///右半邊
            glTranslatef(+.3, 0, 0);///(3)再把轉動中的手臂,掛到肩上
            glRotatef(angle[2], 0,0,1);///(2)再轉動它
            glTranslatef(+.3, .1, 0);///(1)移動旋轉中心,放正中心
            glutSolidTeapot(0.3);///右手臂
            glPushMatrix();
                glTranslatef(+.3, 0, 0);///(3)再把轉動中的手臂,掛到肩上
                glRotatef(angle[3], 0,0,1);///(2)再轉動它
                glTranslatef(+.3, 0, 0);///(1)移動旋轉中心,放正中心
                glutSolidTeapot(0.3);///右手肘
            glPopMatrix();
        glPopMatrix();
    glPopMatrix();
    glutSwapBuffers();
}
const GLfloat light_ambient[]  = { 0.0f, 0.0f, 0.0f, 1.0f };
const GLfloat light_diffuse[]  = { 1.0f, 1.0f, 1.0f, 1.0f };
const GLfloat light_specular[] = { 1.0f, 1.0f, 1.0f, 1.0f };
const GLfloat light_position[] = { 2.0f, 5.0f, -5.0f, 0.0f };

const GLfloat mat_ambient[]    = { 0.7f, 0.7f, 0.7f, 1.0f };
const GLfloat mat_diffuse[]    = { 0.8f, 0.8f, 0.8f, 1.0f };
const GLfloat mat_specular[]   = { 1.0f, 1.0f, 1.0f, 1.0f };
const GLfloat high_shininess[] = { 100.0f };
int main( int argc, char ** argv )
{
    glutInit( &argc, argv);
    glutInitWindowSize(300,300);
    glutInitWindowPosition(700,200);
    glutInitDisplayMode(GLUT_DOUBLE|GLUT_DEPTH);
    glutCreateWindow("week17 review");

    glutKeyboardFunc(keyboard);
    glutMouseFunc(mouse);
    glutMotionFunc(motion);
    glutDisplayFunc(display);

    glEnable(GL_DEPTH_TEST);
    glDepthFunc(GL_LESS);

    glEnable(GL_LIGHT0);
    glEnable(GL_NORMALIZE);
    glEnable(GL_COLOR_MATERIAL);
    glEnable(GL_LIGHTING);

    glLightfv(GL_LIGHT0, GL_AMBIENT,  light_ambient);
    glLightfv(GL_LIGHT0, GL_DIFFUSE,  light_diffuse);
    glLightfv(GL_LIGHT0, GL_SPECULAR, light_specular);
    glLightfv(GL_LIGHT0, GL_POSITION, light_position);

    glMaterialfv(GL_FRONT, GL_AMBIENT,   mat_ambient);
    glMaterialfv(GL_FRONT, GL_DIFFUSE,   mat_diffuse);
    glMaterialfv(GL_FRONT, GL_SPECULAR,  mat_specular);
    glMaterialfv(GL_FRONT, GL_SHININESS, high_shininess);

    glutMainLoop();
}
記得要有 angle.txt 要有內容, 才會內插(會動哦)
-54.00 -63.00 48.00 70.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 
45.00 32.00 -38.00 -40.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 
-54.00 -63.00 48.00 70.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 
45.00 32.00 -38.00 -40.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 
-54.00 -63.00 48.00 70.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 
45.00 32.00 -38.00 -40.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 
-54.00 -63.00 48.00 70.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 
45.00 32.00 -38.00 -40.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 
-54.00 -63.00 48.00 70.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 
45.00 32.00 -38.00 -40.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 
-54.00 -63.00 48.00 70.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 
45.00 32.00 -38.00 -40.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 
-54.00 -63.00 48.00 70.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 
45.00 32.00 -38.00 -40.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 
-54.00 -63.00 48.00 70.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 
45.00 32.00 -38.00 -40.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00