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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
pixels_per_cell = 4
updates_per_frame = 200
lid_speed = 0.1
relaxation_time = 0.515
def get_cavity_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 or y == 1 or x == geometry.size_x-2, 2), # left, right, bottom walls
(lambda x, y: y == geometry.size_y-2, 3), # lid
(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 = $lid_speed;
u_1 = 0.0;
}
""").substitute({
'lid_speed': lid_speed
})
def get_projection():
scale = numpy.diag([(2.0*pixels_per_cell)/screen_x, (2.0*pixels_per_cell)/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//pixels_per_cell,
'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//pixels_per_cell, screen_y//pixels_per_cell),
moments = lbm.moments(optimize = True),
collide = lbm.bgk(f_eq = lbm.equilibrium(), tau = relaxation_time),
boundary_src = boundary,
opengl = True
)
lattice.apply_material_map(
get_cavity_material_map(lattice.geometry))
lattice.sync_material()
projection = get_projection()
def on_display():
for i in range(0,updates_per_frame):
lattice.evolve()
lattice.collect_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(pixels_per_cell)
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()
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