From bf967631c146997d7673798318d94b0a186ec89d Mon Sep 17 00:00:00 2001 From: Adrian Kummerlaender Date: Fri, 6 Sep 2019 22:29:05 +0200 Subject: Add a fun little fake bonfire _simulation_ …using appropriately colored aging particles --- trugfeuer_2d_gl_interop.py | 233 +++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 233 insertions(+) create mode 100644 trugfeuer_2d_gl_interop.py (limited to 'trugfeuer_2d_gl_interop.py') diff --git a/trugfeuer_2d_gl_interop.py b/trugfeuer_2d_gl_interop.py new file mode 100644 index 0000000..c23a355 --- /dev/null +++ b/trugfeuer_2d_gl_interop.py @@ -0,0 +1,233 @@ +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 + +screen_x = 1920 +screen_y = 1200 +pixels_per_cell = 4 +updates_per_frame = 40 +particle_count = 100000 + +inflow = 0.005 +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(): + 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. + ); + + if (CellMoments[3] > 0.0) { + //color = blueRedPalette(CellMoments[3] / 0.2); + color = vec3(0.0,0.0,0.0); + } else { + color = vec3(0.4,0.4,0.4); + } +}""").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) + +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[2]); +}""").substitute({}), GL_VERTEX_SHADER) + +moment_program = shaders.compileProgram(vertex_shader, fragment_shader) +particle_program = shaders.compileProgram(particle_shader, fragment_shader) +projection_id = shaders.glGetUniformLocation(moment_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.sync_material() + +particles = Particles( + lattice.context, + lattice.queue, + lattice.memory.float_type, + 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) + +projection = get_projection() + +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) + + lattice.memory.gl_moments.bind() + + shaders.glUseProgram(moment_program) + glUniformMatrix4fv(projection_id, 1, False, numpy.asfortranarray(projection)) + glVertexPointer(4, GL_FLOAT, 0, lattice.memory.gl_moments) + glPointSize(pixels_per_cell) + glDisable(GL_POINT_SMOOTH) + glDrawArrays(GL_POINTS, 0, lattice.geometry.volume) + + particles.gl_particles.bind() + + shaders.glUseProgram(particle_program) + glUniformMatrix4fv(projection_id, 1, False, numpy.asfortranarray(projection)) + glVertexPointer(4, GL_FLOAT, 0, particles.gl_particles) + glPointSize(1) + glEnable(GL_POINT_SMOOTH) + glDrawArrays(GL_POINTS, 0, particles.count) + + glutSwapBuffers() + +def on_timer(t): + glutTimerFunc(t, on_timer, t) + glutPostRedisplay() + +glutDisplayFunc(on_display) +glutTimerFunc(10, on_timer, 10) + +glutMainLoop() -- cgit v1.2.3