I’m making use of the PsychoPy library, whereby DotStim draws some range of dots on the screen, some moving randomnly (noise dots) and some orderly (right, left, etc.; signal dots). My aim is to change the color of the noise dots in grey, such as the Signal dots (in white on a black screen) would be easier to detect. But I really don’t know how to do this. I guess I need to see where the color of the dots gets defined, and split it there in two; but I don’t seem to find it…
I tried to add two arguments (ColorSignal,ColorNoise), instead of the only module ‘color’ (etc. see code); but I don’t know where I need to change so that it actually works.
Here is the class I’m working on:
#!/usr/bin/env python
# -*- coding: utf-8 -*-
"""This stimulus class defines a field of dots with an update rule that
determines how they change on every call to the .draw() method.
"""
# Part of the PsychoPy library
# Copyright (C) 2018 Jonathan Peirce
# Distributed under the terms of the GNU General Public License (GPL).
# Bugfix by Andrew Schofield.
# Replaces out of bounds but still live dots at opposite edge of aperture instead of randomly within the field. This stops the concentration of dots at one side of field when lifetime is long.
# Update the dot direction immediately for 'walk' as otherwise when the coherence varies some signal dots will inherit the random directions of previous walking dots.
# Provide a visible wrapper function to refresh all the dot locations so that the whole field can be more easily refreshed between trials.
from __future__ import absolute_import, division, print_function
from builtins import str
from builtins import range
# Ensure setting pyglet.options['debug_gl'] to False is done prior to any
# other calls to pyglet or pyglet submodules, otherwise it may not get picked
# up by the pyglet GL engine and have no effect.
# Shaders will work but require OpenGL2.0 drivers AND PyOpenGL3.0+
import pyglet
pyglet.options['debug_gl'] = False
import ctypes
GL = pyglet.gl
import psychopy # so we can get the __path__
from psychopy import logging
# tools must only be imported *after* event or MovieStim breaks on win32
# (JWP has no idea why!)
from psychopy.tools.attributetools import attributeSetter, setAttribute
from psychopy.tools.arraytools import val2array
from psychopy.tools.monitorunittools import cm2pix, deg2pix
from psychopy.visual.basevisual import (BaseVisualStim, ColorMixin,
ContainerMixin)
import numpy
from numpy import pi
class DotStim(BaseVisualStim, ColorMixin, ContainerMixin):
"""This stimulus class defines a field of dots with an update rule
that determines how they change on every call to the .draw() method.
This single class can be used to generate a wide variety of
dot motion types. For a review of possible types and their pros and
cons see Scase, Braddick & Raymond (1996). All six possible motions
they describe can be generated with appropriate choices of the
signalDots (which determines whether signal dots are the 'same' or
'different' on each frame), noiseDots (which determines the locations
of the noise dots on each frame) and the dotLife (which determines
for how many frames the dot will continue before being regenerated).
The default settings (as of v1.70.00) is for the noise dots to have
identical velocity but random direction and signal dots remain the
'same' (once a signal dot, always a signal dot).
For further detail about the different configurations see :ref:`dots`
in the Builder Components section of the documentation.
If further customisation is required, then the DotStim should be
subclassed and its _update_dotsXY and _newDotsXY methods overridden.
"""
def __init__(self,
win,
units='',
nDots=1,
coherence=0.5,
fieldPos=(0.0, 0.0),
fieldSize=(1.0, 1.0),
fieldShape='sqr',
dotSize=2.0,
dotLife=3,
dir=0.0,
speed=0.5,
rgb=None,
color=(1.0, 1.0, 1.0),
colorSpace='rgb',
opacity=1.0,
contrast=1.0,
depth=0,
element=None,
signalDots='same',
noiseDots='direction',
name=None,
autoLog=None):
"""
:Parameters:
fieldSize : (x,y) or [x,y] or single value (applied to both
dimensions). Sizes can be negative and can extend beyond
the window.
"""
# what local vars are defined (these are the init params) for use by
# __repr__
self._initParams = __builtins__['dir']()
self._initParams.remove('self')
super(DotStim, self).__init__(win, units=units, name=name,
autoLog=False) # set at end of init
self.nDots = nDots
# pos and size are ambiguous for dots so DotStim explicitly has
# fieldPos = pos, fieldSize=size and then dotSize as additional param
self.fieldPos = fieldPos # self.pos is also set here
self.fieldSize = val2array(fieldSize, False) # self.size is also set
if type(dotSize) in [tuple, list]:
self.dotSize = numpy.array(dotSize)
else:
self.dotSize = dotSize
if self.win.useRetina:
self.dotSize *= 2 # double dot size to make up for 1/2-size pixels
self.fieldShape = fieldShape
self.__dict__['dir'] = dir
self.speed = speed
self.element = element
self.dotLife = dotLife
self.signalDots = signalDots
self.opacity = float(opacity)
self.contrast = float(contrast)
self.useShaders = False # not needed for dots?
self.colorSpace = colorSpace
if rgb != None:
logging.warning("Use of rgb arguments to stimuli are deprecated."
" Please use color and colorSpace args instead")
self.setColor(rgb, colorSpace='rgb', log=False)
else:
self.setColor(color, log=False)
self.depth = depth
# initialise the dots themselves - give them all random dir and then
# fix the first n in the array to have the direction specified
self.coherence = coherence # using the attributeSetter
self.noiseDots = noiseDots
# initialise a random array of X,Y
self. _verticesBase = self._dotsXY = self._newDotsXY(self.nDots)
# all dots have the same speed
self._dotsSpeed = numpy.ones(self.nDots, 'f') * self.speed
# abs() means we can ignore the -1 case (no life)
self._dotsLife = abs(dotLife) * numpy.random.rand(self.nDots)
# numpy.random.shuffle(self._signalDots) # not really necessary
# set directions (only used when self.noiseDots='direction')
self._dotsDir = numpy.random.rand(self.nDots) * 2 * pi
self._dotsDir[self._signalDots] = self.dir * pi / 180
self._update_dotsXY()
# set autoLog now that params have been initialised
wantLog = autoLog is None and self.win.autoLog
self.__dict__['autoLog'] = autoLog or wantLog
if self.autoLog:
logging.exp("Created %s = %s" % (self.name, str(self)))
def set(self, attrib, val, op='', log=None):
"""DEPRECATED: DotStim.set() is obsolete and may not be supported
in future versions of PsychoPy. Use the specific method for each
parameter instead (e.g. setFieldPos(), setCoherence()...).
"""
self._set(attrib, val, op, log=log)
@attributeSetter
def fieldShape(self, fieldShape):
"""*'sqr'* or 'circle'. Defines the envelope used to present the dots.
If changed while drawing, dots outside new envelope will be respawned.
"""
self.__dict__['fieldShape'] = fieldShape
@attributeSetter
def dotSize(self, dotSize):
"""Float specified in pixels (overridden if `element` is specified).
:ref:`operations <attrib-operations>` are supported."""
self.__dict__['dotSize'] = dotSize
@attributeSetter
def dotLife(self, dotLife):
"""Int. Number of frames each dot lives for (-1=infinite).
Dot lives are initiated randomly from a uniform distribution
from 0 to dotLife. If changed while drawing, the lives of all
dots will be randomly initiated again.
:ref:`operations <attrib-operations>` are supported.
"""
self.__dict__['dotLife'] = dotLife
self._dotsLife = abs(self.dotLife) * numpy.random.rand(self.nDots)
@attributeSetter
def signalDots(self, signalDots):
"""str - 'same' or *'different'*
If 'same' then the signal and noise dots are constant. If different
then the choice of which is signal and which is noise gets
randomised on each frame. This corresponds to Scase et al's (1996)
categories of RDK.
"""
self.__dict__['signalDots'] = signalDots
@attributeSetter
def noiseDots(self, noiseDots):
"""Str. *'direction'*, 'position' or 'walk'
Determines the behaviour of the noise dots, taken directly from
Scase et al's (1996) categories. For 'position', noise dots take a
random position every frame. For 'direction' noise dots follow a
random, but constant direction. For 'walk' noise dots vary their
direction every frame, but keep a constant speed.
"""
self.__dict__['noiseDots'] = noiseDots
self.coherence = self.coherence # update using attributeSetter
@attributeSetter
def element(self, element):
"""*None* or a visual stimulus object
This can be any object that has a ``.draw()`` method and a
``.setPos([x,y])`` method (e.g. a GratingStim, TextStim...)!!
DotStim assumes that the element uses pixels as units.
``None`` defaults to dots.
See `ElementArrayStim` for a faster implementation of this idea.
"""
self.__dict__['element'] = element
@attributeSetter
def fieldPos(self, pos):
"""Specifying the location of the centre of the stimulus
using a :ref:`x,y-pair <attrib-xy>`.
See e.g. :class:`.ShapeStim` for more documentation / examples
on how to set position.
:ref:`operations <attrib-operations>` are supported.
"""
# Isn't there a way to use BaseVisualStim.pos.__doc__ as docstring
# here?
self.pos = pos # using BaseVisualStim. we'll store this as both
self.__dict__['fieldPos'] = self.pos
def setFieldPos(self, val, op='', log=None):
"""Usually you can use 'stim.attribute = value' syntax instead,
but use this method if you need to suppress the log message
"""
setAttribute(self, 'fieldPos', val, log, op) # calls attributeSetter
def setPos(self, newPos=None, operation='', units=None, log=None):
"""Obsolete - users should use setFieldPos instead of setPos
"""
logging.error("User called DotStim.setPos(pos). "
"Use DotStim.SetFieldPos(pos) instead.")
def setFieldSize(self, val, op='', log=None):
"""Usually you can use 'stim.attribute = value' syntax instead,
but use this method if you need to suppress the log message
"""
setAttribute(self, 'fieldSize', val, log, op) # calls attributeSetter
@attributeSetter
def fieldSize(self, size):
"""Specifying the size of the field of dots using a
:ref:`x,y-pair <attrib-xy>`.
See e.g. :class:`.ShapeStim` for more documentation /
examples on how to set position.
:ref:`operations <attrib-operations>` are supported.
"""
# Isn't there a way to use BaseVisualStim.pos.__doc__ as docstring
# here?
self.size = size # using BaseVisualStim. we'll store this as both
self.__dict__['fieldSize'] = self.size
@attributeSetter
def coherence(self, coherence):
"""Scalar between 0 and 1.
Change the coherence (%) of the DotStim. This will be rounded
according to the number of dots in the stimulus.
:ref:`operations <attrib-operations>` are supported.
"""
if not 0 <= coherence <= 1:
raise ValueError('DotStim.coherence must be between 0 and 1')
_cohDots = coherence * self.nDots
self.__dict__['coherence'] = round(_cohDots)/self.nDots
self._signalDots = numpy.zeros(self.nDots, dtype=bool)
self._signalDots[0:int(self.coherence * self.nDots)] = True
# for 'direction' method we need to update the direction of the number
# of signal dots immediately, but for other methods it will be done
# during updateXY
#:::::::::::::::::::: AJS Actually you need to do this for 'walk' also otherwise
#would be signal dots adopt random directions when the become sinal dots in later trails
if self.noiseDots in ['direction', 'position','walk']:
self._dotsDir = numpy.random.rand(self.nDots) * 2 * pi
self._dotsDir[self._signalDots] = self.dir * pi / 180
def setFieldCoherence(self, val, op='', log=None):
"""Usually you can use 'stim.attribute = value' syntax instead,
but use this method if you need to suppress the log message
"""
setAttribute(self, 'coherence', val, log, op) # calls attributeSetter
@attributeSetter
def dir(self, dir):
"""float (degrees). direction of the coherent dots.
:ref:`operations <attrib-operations>` are supported.
"""
# check which dots are signal before setting new dir
signalDots = self._dotsDir == (self.dir * pi / 180)
self.__dict__['dir'] = dir
# dots currently moving in the signal direction also need to update
# their direction
self._dotsDir[signalDots] = self.dir * pi / 180
def setDir(self, val, op='', log=None):
"""Usually you can use 'stim.attribute = value' syntax instead,
but use this method if you need to suppress the log message
"""
setAttribute(self, 'dir', val, log, op)
@attributeSetter
def speed(self, speed):
"""float. speed of the dots (in *units*/frame).
:ref:`operations <attrib-operations>` are supported.
"""
self.__dict__['speed'] = speed
def setSpeed(self, val, op='', log=None):
"""Usually you can use 'stim.attribute = value' syntax instead,
but use this method if you need to suppress the log message
"""
setAttribute(self, 'speed', val, log, op)
def draw(self, win=None):
"""Draw the stimulus in its relevant window. You must call
this method after every MyWin.flip() if you want the
stimulus to appear on that frame and then update the screen again.
"""
if win is None:
win = self.win
self._selectWindow(win)
self._update_dotsXY()
GL.glPushMatrix() # push before drawing, pop after
# draw the dots
if self.element is None:
win.setScale('pix')
GL.glPointSize(self.dotSize)
# load Null textures into multitexteureARB - they modulate with
# glColor
GL.glActiveTexture(GL.GL_TEXTURE0)
GL.glEnable(GL.GL_TEXTURE_2D)
GL.glBindTexture(GL.GL_TEXTURE_2D, 0)
GL.glActiveTexture(GL.GL_TEXTURE1)
GL.glEnable(GL.GL_TEXTURE_2D)
GL.glBindTexture(GL.GL_TEXTURE_2D, 0)
CPCD = ctypes.POINTER(ctypes.c_double)
GL.glVertexPointer(2, GL.GL_DOUBLE, 0,
self.verticesPix.ctypes.data_as(CPCD))
desiredRGB = self._getDesiredRGB(self.rgb, self.colorSpace,
self.contrast)
GL.glColor4f(desiredRGB[0], desiredRGB[1], desiredRGB[2],
self.opacity)
GL.glEnableClientState(GL.GL_VERTEX_ARRAY)
GL.glDrawArrays(GL.GL_POINTS, 0, self.nDots)
GL.glDisableClientState(GL.GL_VERTEX_ARRAY)
else:
# we don't want to do the screen scaling twice so for each dot
# subtract the screen centre
initialDepth = self.element.depth
for pointN in range(0, self.nDots):
_p = self.verticesPix[pointN, :] + self.fieldPos
self.element.setPos(_p)
self.element.draw()
# reset depth before going to next frame
self.element.setDepth(initialDepth)
GL.glPopMatrix()
def _newDotsXY(self, nDots):
"""Returns a uniform spread of dots, according to the
fieldShape and fieldSize
usage::
dots = self._newDots(nDots)
"""
# make more dots than we need and only use those within the circle
if self.fieldShape == 'circle':
while True:
# repeat until we have enough; fetch twice as many as needed
new = numpy.random.uniform(-1, 1, [nDots * 2, 2])
inCircle = (numpy.hypot(new[:, 0], new[:, 1]) < 1)
if sum(inCircle) >= nDots:
return new[inCircle, :][:nDots, :] * self.fieldSize * 0.5
else:
return numpy.random.uniform(-0.5*self.fieldSize[0],
0.5*self.fieldSize[1], [nDots, 2])
def refreshDots(self):
"""Callable user function to choose a new set of dots"""
self._verticesBase = self._dotsXY = self._newDotsXY(self.nDots)
def _update_dotsXY(self):
"""The user shouldn't call this - its gets done within draw().
"""
# Find dead dots, update positions, get new positions for
# dead and out-of-bounds
# renew dead dots
if self.dotLife > 0: # if less than zero ignore it
# decrement. Then dots to be reborn will be negative
self._dotsLife -= 1
dead = (self._dotsLife <= 0.0)
self._dotsLife[dead] = self.dotLife
else:
dead = numpy.zeros(self.nDots, dtype=bool)
# update XY based on speed and dir
# NB self._dotsDir is in radians, but self.dir is in degs
# update which are the noise/signal dots
if self.signalDots == 'different':
# **up to version 1.70.00 this was the other way around,
# not in keeping with Scase et al**
# noise and signal dots change identity constantly
numpy.random.shuffle(self._dotsDir)
# and then update _signalDots from that
self._signalDots = (self._dotsDir == (self.dir * pi / 180))
# update the locations of signal and noise; 0 radians=East!
reshape = numpy.reshape
if self.noiseDots == 'walk':
# noise dots are ~self._signalDots
sig = numpy.random.rand((~self._signalDots).sum())
self._dotsDir[~self._signalDots] = sig * pi * 2
# then update all positions from dir*speed
cosDots = reshape(numpy.cos(self._dotsDir), (self.nDots,))
sinDots = reshape(numpy.sin(self._dotsDir), (self.nDots,))
self._verticesBase[:, 0] += self.speed * cosDots
self._verticesBase[:, 1] += self.speed * sinDots
elif self.noiseDots == 'direction':
# simply use the stored directions to update position
cosDots = reshape(numpy.cos(self._dotsDir), (self.nDots,))
sinDots = reshape(numpy.sin(self._dotsDir), (self.nDots,))
self._verticesBase[:, 0] += self.speed * cosDots
self._verticesBase[:, 1] += self.speed * sinDots
elif self.noiseDots == 'position':
# update signal dots
sd = self._signalDots
sdSum = self._signalDots.sum()
cosDots = reshape(numpy.cos(self._dotsDir[sd]), (sdSum,))
sinDots = reshape(numpy.sin(self._dotsDir[sd]), (sdSum,))
self._verticesBase[sd, 0] += self.speed * cosDots
self._verticesBase[sd, 1] += self.speed * sinDots
# update noise dots
dead = dead + (~self._signalDots) # just create new ones
# handle boundaries of the field
if self.fieldShape in (None, 'square', 'sqr'):
#dead0 = (numpy.abs(self._verticesBase[:, 0]) > 0.5)
#dead1 = (numpy.abs(self._verticesBase[:, 1]) > 0.5)
#dead = dead + dead0 + dead1
out0 = (numpy.abs(self._verticesBase[:, 0]) > 0.5*self.fieldSize[0])
out1 = (numpy.abs(self._verticesBase[:, 1]) > 0.5*self.fieldSize[1])
outofbounds = out0 + out1
elif self.fieldShape == 'circle':
#outofbounds=None
# transform to a normalised circle (radius = 1 all around)
# then to polar coords to check
# the normalised XY position (where radius should be < 1)
normXY = self._verticesBase / 0.5 / self.fieldSize
# add out-of-bounds to those that need replacing
#dead+= (numpy.hypot(normXY[:, 0], normXY[:, 1]) > 1)
outofbounds = (numpy.hypot(normXY[:, 0], normXY[:, 1]) > 1)
# update any dead dots
if sum(dead):
self._verticesBase[dead, :] = self._newDotsXY(sum(dead))
#self._verticesBase[dead, :] = -self._verticesBase[dead,:]
# Reposition any dots that have gone out of bounds. Net effect is to place dot one step inside the boundary on the other side of the aperture.
if sum(outofbounds):
self._verticesBase[outofbounds, :] = self._newDotsXY(sum(outofbounds))
#wind the dots back one step and store as tempary values
# if self.noiseDots == 'position':
# tempvert0=self._verticesBase[sd,0]-self.speed * cosDots
# tempvert1=self._verticesBase[sd,1]-self.speed * sinDots
# else:
# tempvert0=self._verticesBase[:,0]-self.speed * cosDots
# tempvert1=self._verticesBase[:,1]-self.speed * sinDots
# #reflect the position of the dots about the origine of the dot field
# self._verticesBase[outofbounds, 0] = -tempvert0[outofbounds]
# self._verticesBase[outofbounds, 1] = -tempvert1[outofbounds]
# update the pixel XY coordinates in pixels (using _BaseVisual class)
self._updateVertices()
I’m just learning to code, and any help would really really be appreciated! (Even like a hint or so…)
Thanks!