球面線形補間

クォータニオンとクォータニオンを補間するには
『球面線形補間』を使います。

#pragma comment(linker, "/SUBSYSTEM:WINDOWS /ENTRY:mainCRTStartup")
#include <GL/freeglut/freeglut.h>
#include <stdio.h>
#include <math.h>

#define WIDTH 320
#define HEIGHT 240

#define PAI 3.14159

//黄色
GLfloat yellow[] = { 1.0, 1.0, 0.0, 1.0};

bool flag=true;
float t=0.0f;

struct Vector3f{
 float x;
 float y;
 float z;
}vec3d;

//クォータニオン構造体
struct Quaternion{
 float w;
 float x;
 float y;
 float z;
}qua;

//マトリクス構造体
struct MATRIX {
    union {
        struct {
            float _11, _12, _13, _14;
            float _21, _22, _23, _24;
            float _31, _32, _33, _34;
            float _41, _42, _43, _44;
        };
        float mat_4x4[4][4];
  float mat_16[16];
    };
 MATRIX(){//単位行列に初期化
  for(int i=0;i<16;i++){
   this->mat_16[i]=0;
  }
  this->_11=this->_22=this->_33=this->_44=1;
 }
 void PRINT(char* text){
  printf("%s\n%f,%f,%f,%f\n%f,%f,%f,%f\n%f,%f,%f,%f\n%f,%f,%f,%f\n\n",
   text,
   this->_11,this->_21,this->_31,this->_41,
   this->_12,this->_22,this->_32,this->_42,
   this->_13,this->_23,this->_33,this->_43,
   this->_14,this->_24,this->_34,this->_44);
 }
};


//任意軸回転をクォータニオンにする
Quaternion RotateToQuaternion(Vector3f vAxis,float Angle)
{
 Quaternion q;
    float radian = (float)(Angle * (PAI / 180.0) / 2.0);
    float s = sin(radian);
 q.w=cos(radian);
 q.x=vAxis.x*s;
 q.y=vAxis.y*s;
 q.z=vAxis.z*s;
 return q;
}

//クォータニオンを回転行列にする
MATRIX QuaternionToMatrix(Quaternion q){
 MATRIX ret;
    float sx = q.x * q.x;
    float sy = q.y * q.y;
    float sz = q.z * q.z;
    float cx = q.y * q.z;
    float cy = q.x * q.z;
    float cz = q.x * q.y;
    float wx = q.w * q.x;
    float wy = q.w * q.y;
    float wz = q.w * q.z;

 ret._11= 1.0f - 2.0f * (sy + sz);
 ret._12= 2.0f * (cz + wz);
 ret._13= 2.0f * (cy - wy);
 ret._21= 2.0f * (cz - wz);
 ret._22= 1.0f - 2.0f * (sx + sz);
 ret._23= 2.0f * (cx + wx);
 ret._31= 2.0f * (cy + wy);
 ret._32= 2.0f * (cx - wx);
 ret._33= 1.0f - 2.0f * (sx + sy);
 ret._41= 0.0f;
 ret._42= 0.0f;
 ret._43= 0.0f;
 return ret;
}

//回転行列をクォータニオンにする
Quaternion MatrixToQuaternion(MATRIX mat){
 Quaternion q;

    float s;
    float tr = mat._11 + mat._22 + mat._33 + 1.0f;
    if (tr >= 1.0f) {
        s = 0.5f / sqrt(tr);
  q.w= 0.25f / s;
  q.x= (mat._23 - mat._32) * s;
        q.y= (mat._31 - mat._13) * s;
  q.z= (mat._12 - mat._21) * s;
  return q;
    }else{
        float max;
  if(mat._22 > mat._33){
   max = mat._22;
  }else{
   max = mat._33;
  }
       
        if (max < mat._11) {
            s = sqrt(mat._11 - (mat._22 + mat._33) + 1.0f);
            float x = s * 0.5f;
            s = 0.5f / s;
   q.x= x;
   q.y= (mat._12 + mat._21) * s;
   q.z= (mat._31 + mat._13) * s;
   q.w= (mat._23 - mat._32) * s;
            return q;
        }else if (max == mat._22) {
            s = sqrt(mat._22 - (mat._33 + mat._11) + 1.0f);
            float y = s * 0.5f;
            s = 0.5f / s;
   q.x= (mat._12 + mat._21) * s;
            q.y= y;
   q.z= (mat._23 + mat._32) * s;
   q.w= (mat._31 - mat._13) * s;
            return q;
        }else{
            s = sqrt(mat._33 - (mat._11 + mat._22) + 1.0f);
            float z = s * 0.5f;
            s = 0.5f / s;
   q.x= (mat._31 + mat._13) * s;
   q.y= (mat._23 + mat._32) * s;
            q.z= z;
   q.w= (mat._12 - mat._21) * s;
            return q;
        }
    }
}

//球面線形補間
Quaternion Spherical_Linear_Interpolation( Quaternion q1, Quaternion q2, float t)
{
  Quaternion q;
  float qr = q1.w * q2.w + q1.x * q2.x + q1.y * q2.y + q1.z * q2.z;
  float ss = 1.0f - qr * qr;
 
  if (ss == 0.0f) {
   q.w = q1.w;
   q.x = q1.x;
   q.y = q1.y;
   q.z = q1.z;
   return q;
  }
  else {
    float sp = sqrt(ss);
    float ph = acos(qr);
    float pt = ph * t;
    float t1 = sin(pt) / sp;
    float t0 = sin(ph - pt) / sp;
   
 q.w = q1.w * t0 + q2.w * t1;
 q.x = q1.x * t0 + q2.x * t1;
 q.y = q1.y * t0 + q2.y * t1;
 q.z = q1.z * t0 + q2.z * t1;
 return q;
  }
}


MATRIX model;

void display(void)
{
 glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
 glViewport(0, 0, WIDTH, HEIGHT);
 glMatrixMode(GL_PROJECTION);
 glLoadIdentity();
 //視野角,アスペクト比(ウィンドウの幅/高さ),描画する範囲(最も近い距離,最も遠い距離)
 gluPerspective(30.0, (double)WIDTH / (double)HEIGHT, 1.0, 1000.0);
 glMatrixMode(GL_MODELVIEW);

 glLoadIdentity();

 glRotatef(36.8f,1.0f,0.0f,0.0f);
 glGetFloatv(GL_MODELVIEW_MATRIX,&model.mat_16[0]);
 Quaternion q1=MatrixToQuaternion(model);

 glLoadIdentity();

 glRotatef(240.4f,0.0f,1.0f,0.0f);
 glGetFloatv(GL_MODELVIEW_MATRIX,&model.mat_16[0]);
 Quaternion q2=MatrixToQuaternion(model);

 Quaternion q3=Spherical_Linear_Interpolation(q1,q2,t);
 MATRIX mat=QuaternionToMatrix(q3);

 glLoadIdentity();
  gluLookAt(0.0,500.0,500.0,
      0.0,0.0,0.0,
     0.0,1.0,0.0);

 glMultMatrixf(&mat.mat_16[0]);
 glMaterialfv(GL_FRONT, GL_DIFFUSE, yellow);
 glutSolidCube(150.0);

 glutSwapBuffers();
}
void idle(void)
{
 glutPostRedisplay();
}
void Init(){
 glClearColor(0.3f, 0.3f, 0.3f, 1.0f);
 glEnable(GL_DEPTH_TEST);
 glEnable(GL_LIGHTING);
 glEnable(GL_LIGHT0);
}

void timer(int value) {
 if(t>1.0f)flag=false;
 if(t<0.0f)flag=true;
 if(flag){t+=0.01f;}else{t-=0.01f;}
 glutTimerFunc(10 , timer , 0);
}

int main(int argc, char *argv[])
{
 glutInitWindowPosition(100, 100);
 glutInitWindowSize(WIDTH, HEIGHT);
 glutInit(&argc, argv);
 glutInitDisplayMode(GLUT_RGBA | GLUT_DOUBLE);
 glutCreateWindow("球面線形補間");
 glutDisplayFunc(display);
 glutIdleFunc(idle);
 glutTimerFunc(10 , timer , 0);
 Init();
 glutMainLoop();
 return 0;
}

 

 

 

最終更新:2014年04月16日 19:26
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