#!/usr/bin/env python

# -*- coding: utf-8 -*-

# -----------------------------------------------------------------------------

# Copyright 2011 Nicolas P. Rougier (Nicolas.Rougier@inria.fr)

#

# Gray-Scott reation diffusion simulation

#

# This software is governed by the CeCILL license under French law and abiding

# by the rules of distribution of free software. You can use, modify and/ or

# redistribute the software under the terms of the CeCILL license as circulated

# by CEA, CNRS and INRIA at the following URL http://www.cecill.info

#

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# -----------------------------------------------------------------------------

'''

Reaction Diffusion model:

"Numerical simulations of a simple reaction-diffusion model reveal a surprising

variety of irregular spatiotemporal patterns. These patterns arise in response

to finite-amplitude perturbations. Some of them resemble the steady irregular

patterns recently observed in thin gel reactor experiments. Others consist of

spots that grow until they reach a critical size, at which time they divide in

two. If in some region the spots become overcrowded, all of the spots in that

region decay into the uniform background."

John E. Pearson

Complex Patterns in a Simple System

Science 261, 5118, 189-192, 1993

Equations

---------

∂u/∂t = rᵤ∇²u - uv² + f(1-u)

∂v/∂t = rᵥ∇²v + uv² - (f+k)v

Chemical reactions

------------------

U + 2V → 3V

V → P

Variables & parameters

----------------------

U and V and P are chemical species.

u and v represent their concentrations.

rᵤ and rᵥ are their diffusion rates.

k represents the rate of conversion of V to P.

f represents the rate of the process that feeds U and drains U,V and P

References

----------

"Complex Patterns in a Simple System"

J.E. Pearson

Science 261, 5118, 189-192, 1993.

"Pattern Formation by Interacting Chemical Fronts"

K.J. Lee, W.D. McCormick, Qi Ouyang, and H.L. Swinney

Science 261, 5118, 192-194, 1993.

'''

import ctypes

import pyglet

pyglet.options['debug_gl'] = False

import numpy as np

import pyglet.gl as gl

from shader import Shader

if __name__ == '__main__':

# Screen information

# ------------------

platform = pyglet.window.get_platform()

display = platform.get_default_display()

screens = display.get_screens()

screen = screens[0]

# Parameters

# ----------

scale = 4

width, height = screen.width//scale, screen.height//scale

dt = 1.0

dd = 1.5

species = {

# name : [r_u, r_v, f, k]

'Bacteria 1' : [0.16, 0.08, 0.035, 0.065],

'Bacteria 2' : [0.14, 0.06, 0.035, 0.065],

'Coral' : [0.16, 0.08, 0.060, 0.062],

'Fingerprint' : [0.19, 0.05, 0.060, 0.062],

'Spirals' : [0.10, 0.10, 0.018, 0.050],

'Spirals Dense' : [0.12, 0.08, 0.020, 0.050],

'Spirals Fast' : [0.10, 0.16, 0.020, 0.050],

'Unstable' : [0.16, 0.08, 0.020, 0.055],

'Worms 1' : [0.16, 0.08, 0.050, 0.065],

'Worms 2' : [0.16, 0.08, 0.054, 0.063],

'Zebrafish' : [0.16, 0.08, 0.035, 0.060]

}

# Window creation

window = pyglet.window.Window(fullscreen=True,

caption='Gray-Scott Reaction Diffusion',

visible = False, vsync=False, resizable=True)

window.set_location(window.screen.width/2 - window.width/2,

window.screen.height/2 - window.height/2)

# texture_s holds species

# -----------------------

P = np.zeros((height,width,4), dtype=np.float32)

P[:,:] = species['Bacteria 2']

data = P.ctypes.data

texture_s = pyglet.image.Texture.create_for_size(

gl.GL_TEXTURE_2D, width, height, gl.GL_RGBA32F_ARB)

gl.glBindTexture(texture_s.target, texture_s.id)

gl.glTexImage2D(texture_s.target, texture_s.level, gl.GL_RGBA32F_ARB,

width, height, 0, gl.GL_RGBA, gl.GL_FLOAT, data)

gl.glBindTexture(texture_s.target, 0)

# texture_uv holds U & V values (red and green channels)

# ------------------------------------------------------

UV = np.zeros((height,width,4), dtype=np.float32)

UV[:,:,0] = 1.0

r = 32

UV[height/2-r:height/2+r, width/2-r:width/2+r, 0] = 0.50

UV[height/2-r:height/2+r, width/2-r:width/2+r, 1] = 0.25

data = UV.ctypes.data

texture_uv = pyglet.image.Texture.create_for_size(

gl.GL_TEXTURE_2D, width, height, gl.GL_RGBA32F)

gl.glBindTexture(texture_uv.target, texture_uv.id)

gl.glTexImage2D(texture_uv.target, texture_uv.level, gl.GL_RGBA32F_ARB,

width, height, 0, gl.GL_RGBA, gl.GL_FLOAT, data)

gl.glBindTexture(texture_uv.target, 0)

# texture_p holds pointer mask

# ----------------------------

D = np.ones((8,8,4),dtype=np.ubyte)*0

#D[4:12:,4:12] = 0

image = pyglet.image.ImageData(D.shape[1],D.shape[0],'RGBA',D.ctypes.data)

sprite = pyglet.sprite.Sprite(image)

# Reaction-diffusion shader

# -------------------------

vertex_shader = open('./reaction-diffusion.vert').read()

fragment_shader = open('./reaction-diffusion.frag').read()

reaction_shader = Shader(vertex_shader, fragment_shader)

reaction_shader.bind()

reaction_shader.uniformi('texture', 0)

reaction_shader.uniformi('params', 1)

reaction_shader.uniformi('display', 2)

reaction_shader.uniformf('dt', dt)

reaction_shader.uniformf('dx', 1.0/width)

reaction_shader.uniformf('dy', 1.0/height)

reaction_shader.uniformf('dd', dd)

reaction_shader.unbind()

# Color shader

# ------------

vertex_shader = open('./color.vert').read()

fragment_shader = open('./color.frag').read()

color_shader = Shader(vertex_shader, fragment_shader)

color_shader.bind()

color_shader.uniformi('texture', 0)

color_shader.unbind()

# Framebuffer

# -----------

framebuffer = gl.GLuint(0)

gl.glGenFramebuffersEXT(1, ctypes.byref(framebuffer))

gl.glBindFramebufferEXT(gl.GL_FRAMEBUFFER_EXT, framebuffer)

gl.glFramebufferTexture2DEXT(gl.GL_FRAMEBUFFER_EXT, gl.GL_COLOR_ATTACHMENT0_EXT,

gl.GL_TEXTURE_2D, texture_uv.id, 0);

gl.glBindFramebufferEXT(gl.GL_FRAMEBUFFER_EXT, 0)

@window.event

def on_mouse_drag(x, y, dx, dy, button, modifiers):

gl.glBindFramebufferEXT(gl.GL_FRAMEBUFFER_EXT, 0)

@window.event

def on_draw():

color_shader.bind()

#pyglet.clock.schedule_interval(lambda dt: None, 1.0/60.0)

pyglet.clock.schedule(lambda dt: None)

window.set_visible(True)

pyglet.app.run()