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import numpy
from string import Template
from simulation import Lattice, Geometry
from utility.opengl import MomentsVertexBuffer
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 = 480
lattice_y = 300
updates_per_frame = 80
inflow = 0.01
relaxation_time = 0.52
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: x == 1, 3), # inflow
(lambda x, y: x == geometry.size_x-2, 4), # outflow
(lambda x, y: y == 1, 2), # bottom
(lambda x, y: y == geometry.size_y-2, 2), # top
(lambda x, y: x > geometry.size_x//20 and x < 2*geometry.size_x//20 and y < 4*geometry.size_y//9, 2),
(lambda x, y: x > geometry.size_x//20 and x < 2*geometry.size_x//20 and y > 5*geometry.size_y//9, 2),
(circle(geometry.size_x//4, geometry.size_y//2, 50), 2),
(circle(geometry.size_x//4-25, geometry.size_y//2, 50), 1),
(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 = min(time/10000.0 * $inflow, $inflow);
u_1 = 0.0;
}
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)
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.
);
if (CellMoments[3] > 0.0) {
color = blueRedPalette(CellMoments[3] / 0.2);
} else {
color = vec3(0.4,0.4,0.4);
}
}""").substitute({
'size_x': lattice_x,
'inflow': inflow
}), GL_VERTEX_SHADER)
fragment_shader = shaders.compileShader("""
#version 430
in vec3 color;
void main(){
gl_FragColor = 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;
void main() {
gl_Position = projection * vec4(
Particles[0],
Particles[1],
0.,
1.
);
color = vec3(1.0);
}""").substitute({}), GL_VERTEX_SHADER)
shader_program = shaders.compileProgram(vertex_shader, fragment_shader)
particle_program = shaders.compileProgram(particle_shader, fragment_shader)
projection_id = shaders.glGetUniformLocation(shader_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()
moments_vbo = MomentsVertexBuffer(lattice)
particles = Particles(
lattice,
moments_vbo,
numpy.mgrid[
lattice.geometry.size_x//20:2*lattice.geometry.size_x//20:100j,
4*lattice.geometry.size_y//9:5*lattice.geometry.size_y//9:100000/100j
].reshape(2,-1).T)
def on_display():
for i in range(0,updates_per_frame):
lattice.evolve()
moments_vbo.collect()
for i in range(0,updates_per_frame):
particles.update(aging = False)
lattice.sync()
glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT)
shaders.glUseProgram(shader_program)
glUniformMatrix4fv(projection_id, 1, False, numpy.ascontiguousarray(projection))
moments_vbo.bind()
glPointSize(point_size)
glDrawArrays(GL_POINTS, 0, lattice.geometry.volume)
shaders.glUseProgram(particle_program)
glUniformMatrix4fv(projection_id, 1, False, numpy.asfortranarray(projection))
particles.bind()
glPointSize(point_size)
glDrawArrays(GL_POINTS, 0, particles.count)
glutSwapBuffers()
def on_reshape(width, height):
global projection, point_size
glViewport(0,0,width,height)
projection, point_size = get_projection(width, height)
def on_timer(t):
glutTimerFunc(t, on_timer, t)
glutPostRedisplay()
glutDisplayFunc(on_display)
glutReshapeFunc(on_reshape)
glutTimerFunc(10, on_timer, 10)
glutMainLoop()
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