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import numpy
from string import Template
from simulation import Lattice, Geometry
from utility.particles import Particles
from symbolic.generator import LBM
import symbolic.D2Q9 as D2Q9
from OpenGL.GL import *
from OpenGL.GLUT import *
from OpenGL.GL import shaders
from pyrr import matrix44
lattice_x = 512
lattice_y = 320
updates_per_frame = 40
particle_count = 100000
inflow = 0.006
relaxation_time = 0.515
def circle(cx, cy, r):
return lambda x, y: (x - cx)**2 + (y - cy)**2 < r*r
def get_channel_material_map(geometry):
return [
(lambda x, y: x > 0 and x < geometry.size_x-1 and y > 0 and y < geometry.size_y-1, 1), # bulk fluid
(lambda x, y: y == 1, 3), # inflow
(lambda x, y: y == geometry.size_y-2, 4), # outflow
(lambda x, y: x == 1, 2), # bottom
(lambda x, y: x == geometry.size_x-2, 2), # top
(lambda x, y: y > geometry.size_y//20 and y < 2*geometry.size_y//20 and x < 4*geometry.size_x//9, 2),
(lambda x, y: y > geometry.size_y//20 and y < 2*geometry.size_y//20 and x > 5*geometry.size_x//9, 2),
(circle(geometry.size_x//2 , geometry.size_y//8, 3), 2),
(circle(geometry.size_x//2-10, geometry.size_y//8, 3), 2),
(circle(geometry.size_x//2+10, geometry.size_y//8, 3), 2),
(lambda x, y: x == 0 or x == geometry.size_x-1 or y == 0 or y == geometry.size_y-1, 0) # ghost cells
]
boundary = Template("""
if ( m == 2 ) {
u_0 = 0.0;
u_1 = 0.0;
}
if ( m == 3 ) {
u_0 = 0.0;
u_1 = min(time/10000.0 * $inflow, $inflow);
}
if ( m == 4 ) {
rho = 1.0;
}
""").substitute({
'inflow': inflow
})
def get_projection(width, height):
world_width = lattice_x
world_height = world_width / width * height
projection = matrix44.create_orthogonal_projection(-world_width/2, world_width/2, -world_height/2, world_height/2, -1, 1)
translation = matrix44.create_from_translation([-lattice_x/2, -lattice_y/2, 0])
point_size = width / world_width
return numpy.matmul(translation, projection), point_size
def glut_window(fullscreen = False):
glutInit(sys.argv)
glutInitDisplayMode(GLUT_RGBA | GLUT_DOUBLE | GLUT_DEPTH)
if fullscreen:
window = glutEnterGameMode()
else:
glutInitWindowSize(800, 600)
glutInitWindowPosition(0, 0)
window = glutCreateWindow("LBM")
return window
lbm = LBM(D2Q9)
window = glut_window(fullscreen = False)
fragment_shader = shaders.compileShader("""
#version 430
in vec3 color;
layout(location = 0) out vec4 frag_color;
void main(){
frag_color = vec4(color.xyz, 0.0);
}""", GL_FRAGMENT_SHADER)
particle_shader = shaders.compileShader(Template("""
#version 430
layout (location=0) in vec4 particles;
out vec3 color;
uniform mat4 projection;
vec3 fire(float x) {
return mix(
vec3(1.0, 1.0, 0.0),
vec3(1.0, 0.0, 0.0),
x
);
}
void main() {
gl_Position = projection * vec4(
particles[0],
particles[1],
0.,
1.
);
color = fire(1.0-particles[3]);
}""").substitute({
'size_x': lattice_x,
'size_y': lattice_y
}), GL_VERTEX_SHADER)
particle_program = shaders.compileProgram(particle_shader, fragment_shader)
projection_id = shaders.glGetUniformLocation(particle_program, 'projection')
lattice = Lattice(
descriptor = D2Q9,
geometry = Geometry(lattice_x, lattice_y),
moments = lbm.moments(optimize = False),
collide = lbm.bgk(f_eq = lbm.equilibrium(), tau = relaxation_time),
boundary_src = boundary,
opengl = True
)
lattice.apply_material_map(
get_channel_material_map(lattice.geometry))
lattice.sync_material()
particles = Particles(
lattice,
numpy.mgrid[
4*lattice.geometry.size_x//9:5*lattice.geometry.size_x//9:particle_count/100j,
lattice.geometry.size_y//20:2*lattice.geometry.size_y//20:100j,
].reshape(2,-1).T)
def on_display():
for i in range(0,updates_per_frame):
lattice.evolve()
lattice.update_moments()
for i in range(0,updates_per_frame):
particles.update(aging = True)
lattice.sync()
glClear(GL_COLOR_BUFFER_BIT)
shaders.glUseProgram(particle_program)
glUniformMatrix4fv(projection_id, 1, False, numpy.ascontiguousarray(projection))
particles.bind()
glPointSize(point_size)
glEnable(GL_POINT_SMOOTH)
glDrawArrays(GL_POINTS, 0, particles.count)
glutSwapBuffers()
def on_timer(t):
glutTimerFunc(t, on_timer, t)
glutPostRedisplay()
def on_reshape(width, height):
global projection, point_size
glViewport(0,0,width,height)
projection, point_size = get_projection(width, height)
glutDisplayFunc(on_display)
glutReshapeFunc(on_reshape)
glutTimerFunc(10, on_timer, 10)
glutMainLoop()
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