class GratingStimulus(StimulusBase):
"""Simple sine grating stimulus."""
def __init__(self, shared,
lam=10.0, vel=10.0, c_high=255, c_low=0, color=(1.0, 1.0, 1.0)):
StimulusBase.__init__(self, shared)
# Parameters:
self.param_lambda = lam # cm
self.param_velocity = vel # cm/s
self.param_c_high = c_high
self.param_c_low = c_low
self.param_color = np.array(color)
# Set up simple image with grating:
c1, c2 = self.param_color * self.param_c_low, self.param_color * self.param_c_high
self.texture_grating = create_striped_texture(c1, c2, nearest=True)
self.image_grating = OnscreenImage(self.texture_grating,
pos=(0, 0, 0),
scale=(self.getAspectRatio(), 1.0, 1.0),
hpr=(0, 0, 0))
self.image_grating.setTexOffset(TextureStage.getDefault(), 0.0, 0.0)
self.image_grating.setTexScale(TextureStage.getDefault(), self.calibrated_length / self.param_lambda)
def update_stimulus(self, frame_number, time):
offset = (self.param_velocity * time) / self.param_lambda % 1
self.image_grating.setTexOffset(TextureStage.getDefault(), offset, 0.0)
