內插(interpolation)

動作A ------> 動作B

a=0 .................a=1

你的動作(angle[...])

angle[0] = angleOld[0]*(1-a) + angleNew[0]*a;   //內插公式

口訣: 交叉相乘

ex.

a=0, angle[0] 是 angleOld[0]

a=0.1, angleOld[0]*0.9 + angleNew[0]*0.1

a=0.5,  angleOld[0]*0.5 + angleNew[0]*0.5

a=0.9,

a=1, anlge[0] 是 angleNew[0]

最後程式碼!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
紀錄+撥放~

#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("bbbbbbb.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]);

}

}

}

void timer(int t)

{

  glutTimerFunc(100,timer,0);

  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=1;}

else if(key=='s'){

if(fout==NULL)fout=fopen("aaaaaaa.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);

 glutMouseFunc(mouse);

 glutMotionFunc(motion);

 glutMainLoop();

}