1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
|
# -*- coding: utf-8 -*-
# vispy: gallery 30
# -----------------------------------------------------------------------------
# Copyright (c) Vispy Development Team. All Rights Reserved.
# Distributed under the (new) BSD License. See LICENSE.txt for more info.
# -----------------------------------------------------------------------------
# Author: Nicolas P .Rougier
# Date: 06/03/2014
# Abstract: Fake electrons orbiting
# Keywords: Sprites, atom, particles
# -----------------------------------------------------------------------------
import numpy as np
from vispy import gloo
from vispy import app
from vispy.util.transforms import perspective, translate, rotate
# Create vertices
n, p = 100, 150
data = np.zeros(p * n, [('a_position', np.float32, 2),
('a_color', np.float32, 4),
('a_rotation', np.float32, 4)])
trail = .5 * np.pi
data['a_position'][:, 0] = np.resize(np.linspace(0, trail, n), p * n)
data['a_position'][:, 0] += np.repeat(np.random.uniform(0, 2 * np.pi, p), n)
data['a_position'][:, 1] = np.repeat(np.linspace(0, 2 * np.pi, p), n)
data['a_color'] = 1, 1, 1, 1
data['a_color'] = np.repeat(
np.random.uniform(0.75, 1.00, (p, 4)).astype(np.float32), n, axis=0)
data['a_color'][:, 3] = np.resize(np.linspace(0, 1, n), p * n)
data['a_rotation'] = np.repeat(
np.random.uniform(0, 2 * np.pi, (p, 4)).astype(np.float32), n, axis=0)
vert = """
#version 120
uniform mat4 u_model;
uniform mat4 u_view;
uniform mat4 u_projection;
uniform float u_size;
uniform float u_clock;
attribute vec2 a_position;
attribute vec4 a_color;
attribute vec4 a_rotation;
varying vec4 v_color;
mat4 build_rotation(vec3 axis, float angle)
{
axis = normalize(axis);
float s = sin(angle);
float c = cos(angle);
float oc = 1.0 - c;
return mat4(oc * axis.x * axis.x + c,
oc * axis.x * axis.y - axis.z * s,
oc * axis.z * axis.x + axis.y * s,
0.0,
oc * axis.x * axis.y + axis.z * s,
oc * axis.y * axis.y + c,
oc * axis.y * axis.z - axis.x * s,
0.0,
oc * axis.z * axis.x - axis.y * s,
oc * axis.y * axis.z + axis.x * s,
oc * axis.z * axis.z + c,
0.0,
0.0, 0.0, 0.0, 1.0);
}
void main (void) {
v_color = a_color;
float x0 = 1.5;
float z0 = 0.0;
float theta = a_position.x + u_clock;
float x1 = x0*cos(theta) + z0*sin(theta);
float y1 = 0.0;
float z1 = (z0*cos(theta) - x0*sin(theta))/2.0;
mat4 R = build_rotation(a_rotation.xyz, a_rotation.w);
gl_Position = u_projection * u_view * u_model * R * vec4(x1,y1,z1,1);
gl_PointSize = 8.0 * u_size * sqrt(v_color.a);
}
"""
frag = """
#version 120
varying vec4 v_color;
varying float v_size;
void main()
{
float d = 2*(length(gl_PointCoord.xy - vec2(0.5,0.5)));
gl_FragColor = vec4(v_color.rgb, v_color.a*(1-d));
}
"""
# ------------------------------------------------------------ Canvas class ---
class Canvas(app.Canvas):
def __init__(self):
app.Canvas.__init__(self, keys='interactive', size=(800, 800))
self.title = "Atom [zoom with mouse scroll]"
self.translate = 6.5
self.program = gloo.Program(vert, frag)
self.view = translate((0, 0, -self.translate))
self.model = np.eye(4, dtype=np.float32)
self.projection = np.eye(4, dtype=np.float32)
self.apply_zoom()
self.program.bind(gloo.VertexBuffer(data))
self.program['u_model'] = self.model
self.program['u_view'] = self.view
self.program['u_size'] = 5 / self.translate
self.theta = 0
self.phi = 0
self.clock = 0
self.stop_rotation = False
gloo.set_state('translucent', depth_test=False)
self.program['u_clock'] = 0.0
self._timer = app.Timer('auto', connect=self.on_timer, start=True)
self.show()
def on_key_press(self, event):
if event.text == ' ':
self.stop_rotation = not self.stop_rotation
def on_timer(self, event):
if not self.stop_rotation:
self.theta += .05
self.phi += .05
self.model = np.dot(rotate(self.theta, (0, 0, 1)),
rotate(self.phi, (0, 1, 0)))
self.program['u_model'] = self.model
self.clock += np.pi / 100
self.program['u_clock'] = self.clock
self.update()
def on_resize(self, event):
self.apply_zoom()
def on_mouse_wheel(self, event):
self.translate += event.delta[1]
self.translate = max(2, self.translate)
self.view = translate((0, 0, -self.translate))
self.program['u_view'] = self.view
self.program['u_size'] = 5 / self.translate
self.update()
def on_draw(self, event):
gloo.clear('black')
self.program.draw('points')
def apply_zoom(self):
width, height = self.physical_size
gloo.set_viewport(0, 0, width, height)
self.projection = perspective(45.0, width / float(height), 1.0, 1000.0)
self.program['u_projection'] = self.projection
if __name__ == '__main__':
c = Canvas()
app.run()
|
