球の関数を作る Processing

void ellipsoid(float x1, float y1, float z1, float x2, float y2, float z2, int n) {

float dx=abs(x1-x2)/2;

float dy=abs(y1-y2)/2;

float dz=abs(z1-z2)/2;

float s=PI/n;

float s2=s*2;

pushMatrix();

translate((x1+x2)/2, (y1+y2)/2, (z1+z2)/2);

beginShape(TRIANGLE_STRIP);

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

vertex(0, 0, dz);

vertex(dx*sin(s)*cos(s2*i), dy*sin(s)*sin(s2*i), dz*cos(s));

vertex(dx*sin(s)*cos(s2*(i+1)), dy*sin(s)*sin(s2*(i+1)), dz*cos(s));

}

endShape(CLOSE);

for (int i=1;i<=n-2;i++) {

beginShape(TRIANGLES);

for (int j=0;j<n;j++) {

vertex(dx*sin(s*(i+1))*cos(s2*j), dy*sin(s*(i+1))*sin(s2*j), dz*cos(s*(i+1)));

vertex(dx*sin(s*(i+1))*cos(s2*(j+1)), dy*sin(s*(i+1))*sin(s2*(j+1)), dz*cos(s*(i+1)));

//vertex(dx*sin(s*i)*cos(s2*(j+1)),dy*sin(s*i)*sin(s2*(j+1)),dz*cos(s*i));

vertex(dx*sin(s*i)*cos(s2*j), dy*sin(s*i)*sin(s2*j), dz*cos(s*i));

}

endShape(CLOSE);

}

beginShape(TRIANGLE_STRIP);

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

vertex(0, 0, -dz);

vertex(dx*sin(s)*cos(s2*i), -dy*sin(s)*sin(s2*i), dz*cos(s));

vertex(dx*sin(s)*cos(s2*(i+1)), -dy*sin(s)*sin(s2*(i+1)), dz*cos(s));

}

endShape(CLOSE);

popMatrix();

}