Week15

寫程式 讓茶壺可以轉動九十度 利用按鍵"r"

#include<GL/glut.h>
float a=0;
float angle[20]={0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0};
float angleOld[20]={0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0};
float angleNew[20]={90,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0};
void display()
{
glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
glPushMatrix();
glRotatef(angle[0],0,0,1);
glutSolidTeapot(0.3);
glPopMatrix();
glutSwapBuffers();
}
void timer(int t)
{

}
void keyboard(unsigned char key,int x,int y)
{
if(key=='s'){

}else if(key=='r'){
a+=0.1;
angle[0]=angleOld[0]*(1-a)+angleNew[0]*a;
glutPostRedisplay();
}else if(key=='p'){

}
}
int main()
{
glutInitDisplayMode(GLUT_DOUBLE | GLUT_DEPTH);
glutCreateWindow("Week15");
glutKeyboardFunc(keyboard);
glutDisplayFunc(display);
glutMainLoop();
}

修改程式碼之後

#include <stdio.h>

#include<GL/glut.h>

int angleID=0;

float a=0;

float angle[20]={0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0};

float angleOld[20]={0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0};

float angleNew[20]={90,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0};

void display()

{

glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);

glPushMatrix();

glRotatef(angle[0],0,0,1);

glutSolidTeapot(0.3);

glPopMatrix();

glutSwapBuffers();

}

FILE*fout=NULL,*fin=NULL;

void keyboard(unsigned char key,int x,int y)

{

if(key=='0'){

angleID=1;

}else if(key=='1'){

angleID=1;

}else if(key=='2'){

angleID=2;

}else if(key=='s'){

if(fout==NULL)fout=fopen("this_is_my_saved_angles.txt","w+");

for(int i=0;i<20;i++)fprintf(fout,"%f",angle[i]);

fprintf(fout,"\n");

}else if(key=='r'){

if(fin==NULL) fin=fopen("this is my saved angles.txt","r");

a+=0.1;

angle[0]=angleOld[0]*(1-a)+angleNew[0]*a;

if(a>=1){

a=0;

for(int i=0;i<20;i++){

angleOld[i]=angleNew[i];

fscanf(fin,"%f",&angleNew[i]);

}

}

glutPostRedisplay();

}else if(key=='p'){

}

}

float oldX=0,oldY=0;

void mouse(int button,int state,int x,int y){

oldX=x;oldY=y;

}

void motion(int x,int y){

angle[angleID] += (x-oldX); oldX=x;

glutPostRedisplay();

}

int main()

{

glutInitDisplayMode(GLUT_DOUBLE | GLUT_DEPTH);

glutCreateWindow("Week15");

glutKeyboardFunc(keyboard);

glutDisplayFunc(display);

glutMainLoop();

}

加入程式碼 讓茶壺可以自動撥放 不用手動

#include <stdio.h>

#include<GL/glut.h>

int angleID=0;

float a=0;

float angle[20]={0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0};

float angleOld[20]={0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0};

float angleNew[20]={90,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0};

void display()

{

glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);

glPushMatrix();

glRotatef(angle[0],0,0,1);

glutSolidTeapot(0.3);

glPopMatrix();

glutSwapBuffers();

}

FILE*fout=NULL,*fin=NULL;

void readNext(){

if(fin==NULL) fin=fopen("this_is_my_saved_angles.txt","r");

a+=0.1;

for(int i=0;i<20;i++)

angle[i]=angleOld[i]*(1-a)+ angleNew[i]*a;

if(a>=1){

a=0;

for(int i=0;i<20;i++){

angleOld[i]=angleNew[i];

fscanf(fin,"%f",&angleNew[i]);

}

}

}

void timer (int t){

glutTimerFunc(100,timer,0);//100表示要100ms=0.1秒 就會在較一次timer

readNext();

glutPostRedisplay();

} 

void keyboard(unsigned char key,int x,int y)

{

if(key=='0'){

angleID=1;

}else if(key=='1'){

angleID=1;

}else if(key=='2'){

angleID=2;

}else if(key=='s'){

if(fout==NULL)fout=fopen("this_is_my_saved_angles.txt","w+");

for(int i=0;i<20;i++)fprintf(fout,"%f",angle[i]);

fprintf(fout,"\n");

}else if(key=='r'){

readNext();

glutPostRedisplay();

}else if(key=='p'){

glutTimerFunc(0,timer,0);

}

}

float oldX=0,oldY=0;

void mouse(int button,int state,int x,int y){

oldX=x;oldY=y;

}

void motion(int x,int y){

angle[angleID] += (x-oldX); oldX=x;

glutPostRedisplay();

}

int main()

{

glutInitDisplayMode(GLUT_DOUBLE | GLUT_DEPTH);

glutCreateWindow("Week15");

glutKeyboardFunc(keyboard);

glutDisplayFunc(display);

glutMainLoop();

}