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
|
import numpy
from string import Template
from simulation import Lattice, Geometry
from symbolic.generator import LBM
import symbolic.D2Q9 as D2Q9
from OpenGL.GL import *
from OpenGL.GLUT import *
from OpenGL.GL import shaders
screen_x = 1920
screen_y = 1200
cells_per_pixel = 4
updates_per_frame = 200
lid_speed = 0.1
relaxation_time = 0.515
def cavity(geometry, x, y):
if x == 1 or y == 1 or x == geometry.size_x-2:
return 2
elif y == geometry.size_y-2:
return 3
else:
return 1
boundary = Template("""
if ( m == 2 ) {
u_0 = 0.0;
u_1 = 0.0;
}
if ( m == 3 ) {
u_0 = $lid_speed;
u_1 = 0.0;
}
""").substitute({
'lid_speed': lid_speed
})
def get_projection():
scale = numpy.diag([(2.0*cells_per_pixel)/screen_x, (2.0*cells_per_pixel)/screen_y, 1.0, 1.0])
translation = numpy.matrix(numpy.identity(4))
translation[3,0:3] = [-1.0, -1.0, 0.0]
return scale * translation;
def glut_window(fullscreen = False):
glutInit(sys.argv)
glutInitDisplayMode(GLUT_RGBA | GLUT_DOUBLE | GLUT_DEPTH)
if fullscreen:
window = glutEnterGameMode()
else:
glutInitWindowSize(screen_x, screen_y)
glutInitWindowPosition(0, 0)
window = glutCreateWindow("LBM")
return window
lbm = LBM(D2Q9)
window = glut_window(fullscreen = False)
vertex_shader = shaders.compileShader(Template("""
#version 430
layout (location=0) in vec4 CellMoments;
out vec3 color;
uniform mat4 projection;
vec3 blueRedPalette(float x) {
return mix(
vec3(0.0, 0.0, 1.0),
vec3(1.0, 0.0, 0.0),
x
);
}
vec2 fluidVertexAtIndex(uint i) {
const float y = floor(float(i) / $size_x);
return vec2(
i - $size_x*y,
y
);
}
void main() {
const vec2 idx = fluidVertexAtIndex(gl_VertexID);
gl_Position = projection * vec4(
idx.x,
idx.y,
0.,
1.
);
color = blueRedPalette(CellMoments[3] / $lid_speed);
}""").substitute({
'size_x' : screen_x//cells_per_pixel,
'lid_speed': lid_speed
}), GL_VERTEX_SHADER)
fragment_shader = shaders.compileShader("""
#version 430
in vec3 color;
void main(){
gl_FragColor = vec4(color.xyz, 0.0);
}""", GL_FRAGMENT_SHADER)
shader_program = shaders.compileProgram(vertex_shader, fragment_shader)
projection_id = shaders.glGetUniformLocation(shader_program, 'projection')
lattice = Lattice(
descriptor = D2Q9,
geometry = Geometry(screen_x//cells_per_pixel, screen_y//cells_per_pixel),
moments = lbm.moments(optimize = True),
collide = lbm.bgk(f_eq = lbm.equilibrium(), tau = relaxation_time),
boundary_src = boundary,
opengl = True
)
lattice.setup_geometry(cavity)
projection = get_projection()
def on_display():
for i in range(0,updates_per_frame):
lattice.evolve()
lattice.sync_gl_moments()
glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT)
lattice.memory.gl_moments.bind()
glEnableClientState(GL_VERTEX_ARRAY)
shaders.glUseProgram(shader_program)
glUniformMatrix4fv(projection_id, 1, False, numpy.asfortranarray(projection))
glVertexPointer(4, GL_FLOAT, 0, lattice.memory.gl_moments)
glPointSize(cells_per_pixel)
glDrawArrays(GL_POINTS, 0, lattice.geometry.volume)
glDisableClientState(GL_VERTEX_ARRAY)
glutSwapBuffers()
def on_timer(t):
glutTimerFunc(t, on_timer, t)
glutPostRedisplay()
glutDisplayFunc(on_display)
glutTimerFunc(10, on_timer, 10)
glutMainLoop()
|
