class Canvas(app.Canvas):
def __init__(self):
app.Canvas.__init__(self, keys='interactive', size=(512, 512 + 2*32),
title="Marker demo [press space to change marker]")
self.index = 0
self.scale = 1.
self.markers = Markers()
self.markers.set_data(pos)
self.markers.set_style(marker_types[self.index])
def on_initialize(self, event):
# We need to give a transform to our visual
self.transform = STTransform()
self.markers._program.vert['transform'] = self.transform.shader_map()
self.apply_zoom()
def on_draw(self, event):
gloo.clear(color='white')
self.markers.draw()
def on_mouse_wheel(self, event):
"""Use the mouse wheel to zoom."""
self.scale *= 1.25 if event.delta[1] > 0 else 0.8
self.scale = max(min(self.scale, 1e2), 1e-2)
self.apply_zoom()
def on_resize(self, event):
self.apply_zoom()
def apply_zoom(self):
gloo.set_viewport(0, 0, *self.size)
self.transform.scale = (2 * self.scale / self.size[0],
2 * self.scale / self.size[1], 1.)
self.transform.translate = [-1, -1]
self.update()
def on_key_press(self, event):
if event.text == ' ':
self.index = (self.index + 1) % (len(marker_types))
self.markers.set_style(marker_types[self.index])
self.update()
