The Trials of Apollo: The Hidden Oracle

 “Percy waved vaguely toward the north. “She’s in Boston for a few weeks. Some family emergency. The point is—”

 Excerpt From: Rick Riordan. “The Hidden Oracle.”

 So, the timeline is about the same time as Magnus Chase  The Sword of Summer

 Rick is very busy this last year, :)

Bouncing Ball inside a Cone

  I use vector projection and rejection to calculate velocity after bouncing the side of cone, :)

#code
from visual import *
from random import uniform

display(center=(0,2,0),background=(1,1,1), autoscale=False, range=4.5,        
        width=600, height=600,  forward=(-.4,-.3,-1)) #arah kamera

distant_light(direction=(1,1,1), color=color.red)

Cone        = cone(pos = (0,0,0), axis=(0,5,0), radius = 3, opacity = .2) 


bola        = sphere(color=color.green,radius=.2)
bola.y      = 1
bola.x      = -1
bola.z      = 1

v           = vector(1,-1,0)
dt          = 1./16
r           = bola.pos
rc          = Cone.radius
h           = vector(Cone.axis)

def pantul():
    global r,v
    #tumbukan dengan lantai
    if r.y<0:
        r.y = 0
        v.y *= -1

    rp      = vector(r.x,0,r.z)
    hb      = h.y - r.y
    rmaks   = hb/h.y*rc
    c       = h-rmaks*norm(rp)    #vektor garis singgung 
                                  #selimut kerucut dengan bidang singgung
    #tumbukan dengan selimut kerucut
    if mag(rp)>rmaks:
        rp  = norm(rp)*rmaks
        r   = vector(rp.x,r.y,rp.z)
        vp  = dot(v,norm(c))*norm(c)
        v   = 2*vp-v
    print v



def proses():
    global r,v
    a   = vector(0,0,0)
    v   += a*dt
    r   += v*dt

    bola.pos  = r

    pantul()

while 1:
    rate(37)
    proses()

.

Daun Jatuh.

 Megatruh: Apa-apaan ini Kin?

 Kinanthi: Apanya yang apa-apaan Meg?

 M: Puisimu ini?

 K: Kamu baca puisiku? Wow, horee..., aku punya tambahan penggemar

 M: Puisinya bagus...

 
 K: ...dari nol penggemar menjadi satu pengemar...

 M: ...tapi tak logis.

 K: ...dan semua penggemarku, yang cuma satu itu, bilang bagus.

 M: Yeah, tapi gak logis.

 K: Gakpapa, yang penting ada bagus-nya.

 M: Masak disini kamu tulis Daun jatuh tak membenci angin.  Lha jelas daun yang jatuh gara-gara angin itu kan daun tua yang kering, tentu saja pasrah saja dia tertiup angin.

 K: Puisi kan gak perlu logis to Meg.

 M: Ini bukan puisi penambah semangat.

 K: Memang bukan. Puisiku yang ini tentang pasrah setelah berusaha.

 M: Lha kalau gambarannya daun jatuh karena angin, berarti pasrah sampai tua dong.

 K: Eh, iya juga.

 M: Harusnya bikin yang menambah semangat atau tahan banting atau bertahan semacam Daun yang kuat takkan jatuh sekalipun badai.

 K: Wah, trims Meg, ide bagus buat bahan puisi baruku

 M: ... 

Comic Pen

Bouncing Ball inside Sphere

from visual import *
from random import uniform

display(center=(0,2,0),background=(1,1,1), autoscale=False, range=4.5,        
        width=600, height=600,  forward=(-.4,-.3,-1)) #arah kamera

distant_light(direction=(1,1,1), color=color.red)

Ball    = sphere(radius=2, length=4, opacity=.3)


bola        = sphere(color=color.green,radius=.2)
bola.y      = 1
bola.x      = -1
bola.z      = 1

v           = vector(2,1,0)
dt          = 1./16
r           = bola.pos
rc          = Ball.radius

def pantul():
    global r,v
    if mag(r)>=rc:
        r   = 1.99*norm(r)
        vp  = (dot(v,norm(r)))*norm(r)
        vr  = v-vp
        v   = vr - vp

def proses():
    global r,v
    a   = vector(0,0,0)
    v   += a*dt
    r   += v*dt

    bola.pos  = r

    pantul()

while 1:
    rate(37)
    proses()

.

Bouncing inside Cylinder

from visual import *
from random import uniform

display(center=(0,2,0),background=(1,1,1), autoscale=False, range=4.5,        
        width=600, height=600,  forward=(-.4,-.3,-1)) #arah kamera

distant_light(direction=(1,1,1), color=color.red)

silinder    = cylinder(radius=2, length=4, opacity=.3)
silinder.rotate(angle=pi/2, axis=(0,0,1),origin=(0,0,0))


bola        = sphere(color=color.green,radius=.2)
bola.y      = 0
bola.x      = 0
bola.z      = 1

v           = vector(2,0,0)
dt          = 1./16
r           = bola.pos
rc          = silinder.radius

def pantul():
    global r,v
    if mag(r)>=rc:
        r   = 1.9*norm(r)
        vp  = (dot(v,norm(r)))*norm(r)
        vr  = v-vp
        v   = vr - vp

def proses():
    global r,v
    a   = vector(0,0,0)
    v   += a*dt
    r   += v*dt

    bola.pos  = r

    pantul()

while 1:
    rate(7)
    proses()

.

Dot Product