3dgraphics1_toushi.c

计算机图形学

   x0 = Q.x;
   y0 = Q.y;

   x = x0;
   y = y0 + radius;
   d = 5 - 4*radius;
   deltaE = 12;
   deltaSE = 20 - 8*radius;
   CirclePoints(x0,y0,x,y,color);
   while((y-y0)>(x-x0))
   {
      if(d<=0)
      {
        d = d + deltaE;
        deltaSE=deltaSE + 8;
      }
      else
      {
         d = d + deltaSE;
         deltaSE=deltaSE + 16;
         y--;
      }
      deltaE=deltaE + 8;
      x++;
      CirclePoints(x0,y0,x,y,color);
   }

}



/***********************/
/*   椭圆的中点算法    */
/***********************/


/* 椭圆的4对称点的显示 */
void EllipsePoints(int x0,int y0,int x,int y,int color) /*椭圆的中心为:(x0,y0)*/
{
  putpixel(x,y,color);              /*(x,  y) */
  putpixel(2*x0-x,y,color);         /*(-x, y) */
  putpixel(2*x0-x,2*y0-y,color);    /*(-x,-y) */
  putpixel(x,2*y0-y,color);         /*(x, -y) */
}


/* 椭圆的中点算法 */
void MidPointEllipse(Point Q,int a,int b,int color)
{
  int x,y,xP,yP,x0,y0;
  float d,squrarea,squrareb;
   x0 = Q.x;
   y0 = Q.y;


  squrarea = a * a;
  squrareb = b * b;

  /*计算分解点P*/
  xP = (int)(0.5 + squrarea/sqrt(squrarea + squrareb));
  yP = (int)(0.5 + squrareb/sqrt(squrarea + squrareb));

 /* 生成上半部椭圆*/
  x = x0;
  y = y0 + b;
  d = 4 * (squrareb - squrarea * b) + squrarea;
  EllipsePoints(x0,y0,x,y,color);
  while((x - x0)<xP)
  {
    if(d<=0)
       d = d + 4 * squrareb * (2 * (x - x0) + 3);
    else
       {
         d = d + 4 * squrareb * (2 * (x - x0) + 3)-8 * squrarea * ((y - y0) - 1);
         y--;
       }
    x++;
    EllipsePoints(x0,y0,x,y,color);
  }

  /* 生成下半部椭圆*/
  x = x0 + a;
  y = y0;
  d = 4 * (squrarea - squrareb * a) + squrareb;
  EllipsePoints(x0,y0,x,y,color);
  while((y-y0) < yP)
  {
    if(d<=0)
       d = d + 4 * squrarea * (2 * (y - y0) + 3);
    else
       {
         d = d + 4 * squrarea * (2 * (y - y0) + 3)-8 * squrareb * ((x - x0) - 1);
         x--;
       }
     y++;
   EllipsePoints(x0,y0,x,y,color);
  }
}


/***********************/
/*     矩形的算法      */
/***********************/
void Rectangle(Point LeftTop,Point RightDown,int color)
{
  int x1,y1,x2,y2,x,y;
  x1 = LeftTop.x;
  x2 = RightDown.x;
  y1 = LeftTop.y;
  y2 = RightDown.y;
  x = x1;
  while(x<=x2)
  {
    putpixel(x,y1,color);
    putpixel(x,y2,color);
    x++;
  }

  y = y1;
  while(y<=y2)
  {
     putpixel(x1,y,color);
     putpixel(x2,y,color);
     y++;
  }

}


/*************************/
/******   网格球     *****/
/*************************/

void QiuEC(Point o,int r,int color) /*  球心为(x,y) */
{
  float i,X,Y,ra,rb;
  int k,x,y;
  x = o.x;
  y = o.y;
  MidPointEllipse(o,r,15,color);
  MidPointCircle_1(o,r,color);
  for(i=1;i<=(r/5);i++)
  {

     MidPointEllipse(o,5*i,r,color);

  }
  k = (int)(r/4);
  for(i=1;i<4;i++)
  {
     o.y = y-(4-i)*k;
     MidPointEllipse(o,sqrt(2*r*(k*i)-k*i*k*i),i*4,color);
     o.y = y+(4-i)*k;
     MidPointEllipse(o,sqrt(2*r*(k*i)-k*i*k*i),i*4,color);
  }
}





/*****************************/
/**                         **/
/**     矩形的旋转          **/
/**                         **/
/*****************************/
void Rectangle_XuanZhuan(Rect R,float q)
{
  int x1,y1,x2,y2,x,y,color,X,Y;

  color = R.color;

  x1 = R.LeftTop.x;
  y1 = R.LeftTop.y;

  x2 = R.RightDown.x;
  y2 = R.RightDown.y;

  x = x1;
  while(x<=x2)
  {
    X = x;
    Y = y1;
    XuanZhuan(&X,&Y,q);
       putpixel(X,Y,color);

    X = x;
    Y = y2;
    XuanZhuan(&X,&Y,q);
       putpixel(X,Y,color);

    x++;
  }

  y = y1;
  while(y<=y2)
  {
     X = x1;
     Y = y;
     XuanZhuan(&X,&Y,q);
       putpixel(X,Y,color);

     X = x2;
     Y = y;
     XuanZhuan(&X,&Y,q);
       putpixel(X,Y,color);
     y++;
  }

}




/******************************/
/*                            */
/*       椭圆的平移           */
/*                            */
/******************************/

/*平移后椭圆的4对称点的显示*/
void EllipsePoints_PinYi(int x0,int y0,int x,int y,int color,int tx,int ty) /*椭圆的中心为:(x0,y0)*/
{
  int X,Y;
  X = x;
  Y = y;
  PinYi(&X,&Y,tx,ty);
     putpixel(X,Y,color);      /*(x,  y)*/

  X = 2*x0-x;
  Y = y;
  PinYi(&X,&Y,tx,ty);
     putpixel(X,Y,color);      /*(-x, y)*/

  X = 2*x0-x;
  Y = 2*y0-y;
  PinYi(&X,&Y,tx,ty);
     putpixel(X,Y,color);      /*(-x,-y)*/

  X = x;
  Y = 2*y0-y;
  PinYi(&X,&Y,tx,ty);
     putpixel(X,Y,color);       /*(x, -y)*/
}

/* 椭圆的平移*/

void MidPointEllipse_PinYi(TuoYuan E,int tx,int ty)
{
  int x,y,xP,yP,x0,y0,a,b,color;
  float d,squrarea,squrareb;

   a = E.a;
   b = E.b;
   color = E.color;
   x0 = E.o.x;
   y0 = E.o.y;


  squrarea = a * a;
  squrareb = b * b;

  /*计算分解点P*/
  xP = (int)(0.5 + squrarea/sqrt(squrarea + squrareb));
  yP = (int)(0.5 + squrareb/sqrt(squrarea + squrareb));

 /* 生成上半部椭圆*/
  x = x0;
  y = y0 + b;
  d = 4 * (squrareb - squrarea * b) + squrarea;

  EllipsePoints_PinYi(x0,y0,x,y,color,tx,ty);

  while((x - x0)<xP)
  {
    if(d<=0)
       d = d + 4 * squrareb * (2 * (x - x0) + 3);
    else
       {
         d = d + 4 * squrareb * (2 * (x - x0) + 3)-8 * squrarea * ((y - y0) - 1);
         y--;
       }
    x++;

    EllipsePoints_PinYi(x0,y0,x,y,color,tx,ty);

  }

  /* 生成下半部椭圆*/
  x = x0 + a;
  y = y0;
  d = 4 * (squrarea - squrareb * a) + squrareb;

  EllipsePoints_PinYi(x0,y0,x,y,color,tx,ty);

  while((y-y0) < yP)
  {
    if(d<=0)
       d = d + 4 * squrarea * (2 * (y - y0) + 3);
    else
       {
         d = d + 4 * squrarea * (2 * (y - y0) + 3)-8 * squrareb * ((x - x0) - 1);
         x--;
       }
     y++;

   EllipsePoints_PinYi(x0,y0,x,y,color,tx,ty);

  }
}

/******************************/
/*                            */
/*       椭圆的旋转           */
/*                            */
/******************************/

/* 椭圆旋转后的4对称点的显示 */
void EllipsePoints_XuanZhuan(int m,int n,int x0,int y0,int x,int y,int color,float q) /*椭圆的中心为:(x0,y0),绕点(m,n)旋转*/
{
  int X,Y;
  X = x;
  Y = y;
  XuanZhuan_RY(m,n,&X,&Y,q);
     putpixel(X,Y,color);               /*(x,  y) */


  X = 2*x0-x;
  Y = y;
  XuanZhuan_RY(m,n,&X,&Y,q);
     putpixel(X,Y,color);              /*(-x, y) */


  X = 2*x0-x;
  Y = 2*y0-y;
  XuanZhuan_RY(m,n,&X,&Y,q);
     putpixel(X,Y,color);             /*(-x,-y) */

  X = x;
  Y = 2*y0-y;
  XuanZhuan_RY(m,n,&X,&Y,q);
     putpixel(X,Y,color);             /*(x, -y) */

}

/*        椭圆的旋转    */

MidPointEllipse_XuanZhuan(TuoYuan E,Point A,float q) /*绕A点旋转*/
{
  int x,y,xP,yP,x0,y0,a,b,color,m,n;
  float  d,squrarea,squrareb;
  m = A.x;
  n = A.y;
  x0 = E.o.x;
  y0 = E.o.y;
  a = E.a;
  b = E.b;
  color  = E.color;


  squrarea = a * a;
  squrareb = b * b;

  /*计算分解点P*/
  xP = (int)(0.5 + squrarea/sqrt(squrarea + squrareb));
  yP = (int)(0.5 + squrareb/sqrt(squrarea + squrareb));

 /* 生成上半部椭圆*/
  x = x0;
  y = y0 + b;
  d = 4 * (squrareb - squrarea * b) + squrarea;

  EllipsePoints_XuanZhuan(m,n,x0,y0,x,y,color,q);

  while((x - x0)<=xP)
  {
    if(d<=0)
       d = d + 4 * squrareb * (2 * (x - x0) + 3);
    else
       {
         d = d + 4 * squrareb * (2 * (x - x0) + 3)-8 * squrarea * ((y - y0) - 1);
         y--;
       }
    x++;

  EllipsePoints_XuanZhuan(m,n,x0,y0,x,y,color,q);

  }
  /* 生成下半部椭圆*/
  x = x0 + a;
  y = y0;
  d = 4 * (squrarea - squrareb * a) + squrareb;

 EllipsePoints_XuanZhuan(m,n,x0,y0,x,y,color,q);

  while((y-y0) < yP)
  {
    if(d<=0)
       d = d + 4 * squrarea * (2 * (y - y0) + 3);
    else
       {
         d = d + 4 * squrarea * (2 * (y - y0) + 3)-8 * squrareb * ((x - x0) - 1);
         x--;
       }
     y++;

  EllipsePoints_XuanZhuan(m,n,x0,y0,x,y,color,q);
  }
}


/******************************/
/*                            */
/*       椭圆的放缩           */
/*                            */
/******************************/

/* 椭圆放缩后的4对称点的显示 */
void EllipsePoints_FangSuo(int m,int n,int x0,int y0,int x,int y,int color,float sx,float sy) /*椭圆的中心为:(x0,y0),以(m,n)为参考点放缩*/
{
  int X,Y;
  X = x;
  Y = y;
  FangSuo_RY(m,n,&X,&Y,sx,sy);
     putpixel(X,Y,color);               /*(x,  y) */


  X = 2*x0-x;
  Y = y;
  FangSuo_RY(m,n,&X,&Y,sx,sy);
     putpixel(X,Y,color);              /*(-x, y) */


  X = 2*x0-x;
  Y = 2*y0-y;
  FangSuo_RY(m,n,&X,&Y,sx,sy);
     putpixel(X,Y,color);             /*(-x,-y) */

  X = x;
  Y = 2*y0-y;
  FangSuo_RY(m,n,&X,&Y,sx,sy);
     putpixel(X,Y,color);             /*(x, -y) */

}

/*        椭圆的放缩     */

void MidPointEllipse_FangSuo(TuoYuan E,Point A,float sx,float sy) /*以A点为参考点放缩*/
{
  int x,y,xP,yP,x0,y0,a,b,color,m,n;
  float  d,squrarea,squrareb;
  m = A.x;
  n = A.y;
  x0 = E.o.x;
  y0 = E.o.y;
  a = E.a;
  b = E.b;
  color  = E.color;


  squrarea = a * a;
  squrareb = b * b;

  /*计算分解点P*/
  xP = (int)(0.5 + squrarea/sqrt(squrarea + squrareb));
  yP = (int)(0.5 + squrareb/sqrt(squrarea + squrareb));

 /* 生成上半部椭圆*/
  x = x0;
  y = y0 + b;
  d = 4 * (squrareb - squrarea * b) + squrarea;

  EllipsePoints_FangSuo(m,n,x0,y0,x,y,color,sx,sy);

  while((x - x0)<=xP)
  {
    if(d<=0)
       d = d + 4 * squrareb * (2 * (x - x0) + 3);
    else
       {
         d = d + 4 * squrareb * (2 * (x - x0) + 3)-8 * squrarea * ((y - y0) - 1);
         y--;
       }
    x++;

  EllipsePoints_FangSuo(m,n,x0,y0,x,y,color,sx,sy);

  }
  /* 生成下半部椭圆*/
  x = x0 + a;
  y = y0;
  d = 4 * (squrarea - squrareb * a) + squrareb;

 EllipsePoints_FangSuo(m,n,x0,y0,x,y,color,sx,sy);

  while((y-y0) < yP)
  {
    if(d<=0)
       d = d + 4 * squrarea * (2 * (y - y0) + 3);
    else
       {
         d = d + 4 * squrarea * (2 * (y - y0) + 3)-8 * squrareb * ((x - x0) - 1);
         x--;
       }
     y++;

  EllipsePoints_FangSuo(m,n,x0,y0,x,y,color,sx,sy);
  }
}


/************************/
/**                    **/
/**   圆的错切变换     **/
/**                    **/
/************************/


/* 错切后圆的8对称点的显示 */
void CirclePoints_CuoQie(int m,int n,int x0,int y0,int x,int y,int color,float q,int flag)/* 圆心为（x0,y0);以(m,n)为参考点*/
{
  int X,Y;
  X = x;
  Y = y;
  CuoQie_RY(m,n,&X,&Y,q,flag);
       putpixel(X,Y,color);                /*(x,  y) */

  X = x0-y0+y;
  Y = y0-x0+x;
  CuoQie_RY(m,n,&X,&Y,q,flag);
        putpixel(X,Y,color);               /*(y,  x) */

  X = x0+y0-y;
  Y = y0-x0+x;
  CuoQie_RY(m,n,&X,&Y,q,flag);
        putpixel(X,Y,color);              /*(-y, x) */

  X = 2*x0-x;
  Y = y;
  CuoQie_RY(m,n,&X,&Y,q,flag);
        putpixel(X,Y,color);              /*(-x, y) */

  X = x0-y0+y;
  Y = y0+x0-x;
  CuoQie_RY(m,n,&X,&Y,q,flag);
        putpixel(X,Y,color);              /*(y, -x) */

  X = x;
  Y = 2*y0-y;
  CuoQie_RY(m,n,&X,&Y,q,flag);
       putpixel(X,Y,color);               /*(x, -y) */

  X =2*x0-x;
  Y =2*y0-y;
  CuoQie_RY(m,n,&X,&Y,q,flag);
       putpixel(X,Y,color);               /*(-x,-y) */

  X =x0+y0-y;
  Y =y0+x0-x;
  CuoQie_RY(m,n,&X,&Y,q,flag);
       putpixel(X,Y,color);               /*(-y,-x) */
}

/*  圆 的错切 */
void MidPointCircle_CuoQie(Yuan C,Point A,float q,int flag)/* 圆心为（x0,y0);*/
{
   int x,y,d,deltaE,deltaSE,x0,y0,radius,color,m,n;
   m = A.x;
   n = A.y;
   x0 = C.o.x;
   y0 = C.o.y;
   radius = C.r;
   color = C.color;

   x = x0;
   y = y0 + radius;
   d = 5 - 4*radius;
   deltaE = 12;
   deltaSE = 20 - 8*radius;

     CirclePoints_CuoQie(m,n,x0,y0,x,y,color,q,flag);
   while((y-y0)>(x-x0))
   {
      if(d<=0)
      {
        d = d + deltaE;
        deltaSE=deltaSE + 8;
      }
      else
      {
         d = d + deltaSE;
         deltaSE=deltaSE + 16;
         y--;
      }
      deltaE=deltaE + 8;
      x++;
      CirclePoints_CuoQie(m,n,x0,y0,x,y,color,q,flag);
   }

}





/*****************************/
/**                         **/
/**     四棱锥的画法        **/
/**                         **/
/*****************************/
void Slz3D(Point3D A,int h,int r,int d,float qx,float qy,float qz)
{
   int x,y,z,X,Y,Z,i,j,k;
   Point3D A1,A2,A3,A4,P;
   Point B1,B2,B3,B4,Q,temp;


   x = A.x; y = A.y; z = A.z;

   A1.x = x + r/2.0; A1.y = y - r/2.0; A1.z = A.z;
   A2.x = x + r/2.0; A2.y = y + r/2.0; A2.z = A.z;
   A3.x = x - r/2.0; A3.y = y + r/2.0; A3.z = A.z;
   A4.x = x - r/2.0; A4.y = y - r/2.0; A4.z = A.z;

   P.x = A.x; P.y = A.y; P.z = A.z - h;



   X = P.x; Y = P.y; Z = P.z;
      Point3D_2D_TouShi(&X,&Y,&Z,d,qx,qy,qz);
   Q.x = X; Q.y = Y;

   X = A4.x; Y = A4.y; Z = A4.z;
   j = A4.y;
   while(j<=A3.y)
   {
       Point3D_2D_TouShi(&X,&Y,&Z,d,qx,qy,qz);
      temp.x = X; temp.y = Y;
        MidPointLine(Q,temp,14);