69 lines
1.4 KiB
Python
69 lines
1.4 KiB
Python
try:
|
|
from ctypes import c_float
|
|
except ImportError:
|
|
pass
|
|
|
|
import pyglet.gl as pgl
|
|
from math import sqrt as _sqrt, acos as _acos
|
|
|
|
|
|
def cross(a, b):
|
|
return (a[1] * b[2] - a[2] * b[1],
|
|
a[2] * b[0] - a[0] * b[2],
|
|
a[0] * b[1] - a[1] * b[0])
|
|
|
|
|
|
def dot(a, b):
|
|
return a[0] * b[0] + a[1] * b[1] + a[2] * b[2]
|
|
|
|
|
|
def mag(a):
|
|
return _sqrt(a[0]**2 + a[1]**2 + a[2]**2)
|
|
|
|
|
|
def norm(a):
|
|
m = mag(a)
|
|
return (a[0] / m, a[1] / m, a[2] / m)
|
|
|
|
|
|
def get_sphere_mapping(x, y, width, height):
|
|
x = min([max([x, 0]), width])
|
|
y = min([max([y, 0]), height])
|
|
|
|
sr = _sqrt((width/2)**2 + (height/2)**2)
|
|
sx = ((x - width / 2) / sr)
|
|
sy = ((y - height / 2) / sr)
|
|
|
|
sz = 1.0 - sx**2 - sy**2
|
|
|
|
if sz > 0.0:
|
|
sz = _sqrt(sz)
|
|
return (sx, sy, sz)
|
|
else:
|
|
sz = 0
|
|
return norm((sx, sy, sz))
|
|
|
|
rad2deg = 180.0 / 3.141592
|
|
|
|
|
|
def get_spherical_rotatation(p1, p2, width, height, theta_multiplier):
|
|
v1 = get_sphere_mapping(p1[0], p1[1], width, height)
|
|
v2 = get_sphere_mapping(p2[0], p2[1], width, height)
|
|
|
|
d = min(max([dot(v1, v2), -1]), 1)
|
|
|
|
if abs(d - 1.0) < 0.000001:
|
|
return None
|
|
|
|
raxis = norm( cross(v1, v2) )
|
|
rtheta = theta_multiplier * rad2deg * _acos(d)
|
|
|
|
pgl.glPushMatrix()
|
|
pgl.glLoadIdentity()
|
|
pgl.glRotatef(rtheta, *raxis)
|
|
mat = (c_float*16)()
|
|
pgl.glGetFloatv(pgl.GL_MODELVIEW_MATRIX, mat)
|
|
pgl.glPopMatrix()
|
|
|
|
return mat
|