Add 3d lid driven cavity OpenGL visualization

1 files changed, 185 insertions, 0 deletions

diff --git a/ldc_3d_gl_interop.py b/ldc_3d_gl_interop.py
new file mode 100644
index 0000000..483ea1a
--- /dev/null
+++ b/ldc_3d_gl_interop.py
@@ -0,0 +1,185 @@
+import numpy
+from string import Template
+
+from simulation         import Lattice, Geometry
+from utility.particles  import Particles
+from symbolic.generator import LBM
+
+import symbolic.D3Q19 as D3Q19
+
+from OpenGL.GL   import *
+from OpenGL.GLUT import *
+
+from OpenGL.GL import shaders
+
+from pyrr import matrix44
+
+lattice_x = 64
+lattice_y = 32
+lattice_z = 32
+
+updates_per_frame = 20
+particle_count = 50000
+
+lid_speed = 0.001
+relaxation_time = 0.515
+
+def get_cavity_material_map(geometry):
+    return [
+        (lambda x, y, z: x > 0 and x < geometry.size_x-1 and
+                         y > 0 and y < geometry.size_y-1 and
+                         z > 0 and z < geometry.size_z-1,                                                1), # bulk fluid
+        (lambda x, y, z: x == 1 or y == 1 or z == 1 or x == geometry.size_x-2 or y == geometry.size_y-2, 2), # walls
+        (lambda x, y, z: z == geometry.size_z-2,                                                         3), # lid
+        (lambda x, y, z: x == 0 or x == geometry.size_x-1 or
+                         y == 0 or y == geometry.size_y-1 or
+                         z == 0 or z == geometry.size_z-1,                                               0)  # ghost cells
+    ]
+
+boundary = """
+    if ( m == 2 ) {
+        u_0 = 0.0;
+        u_1 = 0.0;
+        u_2 = 0.0;
+    }
+    if ( m == 3 ) {
+        u_0 = 0.1;
+        u_1 = 0.0;
+        u_2 = 0.0;
+    }
+"""
+
+def get_projection(width, height):
+    world_width = lattice_x
+    world_height = world_width / width * height
+
+    projection = matrix44.create_perspective_projection(45.0, width/height, 0.1, 1000.0)
+    look = matrix44.create_look_at(
+        eye    = [lattice_x/2, -2*lattice_y, lattice_z/2],
+        target = [lattice_x/2, lattice_y/2, lattice_z/2],
+        up     = [0, 0, 1])
+    rotate = matrix44.create_from_axis_rotation(axis=[0,1,0], theta=0.2)
+
+    point_size = 1
+
+    return numpy.matmul(look, 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, 500)
+        glutInitWindowPosition(0, 0)
+        window = glutCreateWindow("LBM")
+
+    return window
+
+lbm = LBM(D3Q19)
+
+window = glut_window(fullscreen = False)
+
+vertex_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],
+        particles[2],
+        1.
+    );
+
+    color = fire(1.0-particles[3]);
+}""").substitute({}), 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   = D3Q19,
+    geometry     = Geometry(lattice_x, lattice_y, lattice_z),
+    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()
+
+particles = Particles(
+    lattice.context,
+    lattice.queue,
+    lattice.memory.float_type,
+    numpy.mgrid[
+        6*lattice.geometry.size_x//8:7*lattice.geometry.size_x//8:10j,
+        lattice.geometry.size_y//8:7*lattice.geometry.size_y//8:particle_count/100j,
+        6*lattice.geometry.size_z//8:7*lattice.geometry.size_z//8:10j,
+    ].reshape(3,-1).T)
+
+def on_display():
+    for i in range(0,updates_per_frame):
+        lattice.evolve()
+
+    lattice.collect_gl_moments()
+
+    for i in range(0,updates_per_frame):
+        lattice.update_gl_particles(particles, aging = True)
+
+    lattice.sync()
+
+    glClear(GL_COLOR_BUFFER_BIT)
+    glEnableClientState(GL_VERTEX_ARRAY)
+
+    particles.gl_particles.bind()
+
+    shaders.glUseProgram(shader_program)
+    glUniformMatrix4fv(projection_id, 1, False, numpy.ascontiguousarray(projection))
+    glVertexPointer(4, GL_FLOAT, 0, particles.gl_particles)
+    glPointSize(point_size)
+    glEnable(GL_POINT_SMOOTH)
+    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()