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 = 80 inflow = 0.02 relaxation_time = 0.51 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 == 0 or x == geometry.size_x-1 or y == 0 or y == geometry.size_y-1, 0) # ghost cells ] def get_obstacles(geometry): ys = numpy.linspace(geometry.size_y//50, geometry.size_y-geometry.size_y//50, num = 20) xs = [ 50 for i, y in enumerate(ys) ] rs = [ geometry.size_x//100 for i, y in enumerate(ys) ] return list(zip(xs, ys, rs)) def get_obstacles_material_map(obstacles): indicator = lambda ox, oy, r: (lambda x, y: (ox - x)**2 + (oy - y)**2 < r*r) return [ (indicator(ox, oy, r), 2) for ox, oy, r in obstacles ] 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(): 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] / 0.08); }""").substitute({ 'size_x': screen_x//pixels_per_cell, '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) 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 = 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.apply_material_map( get_obstacles_material_map(get_obstacles(lattice.geometry))) lattice.sync_material() 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(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()