# from `bindings/python/examples/quickstart.py`
import time
import numpy as np
import numpy.random as nr
# Import the library.
from datoviz import canvas, run, colormap
# Create a new canvas and scene. There's only 1 subplot (panel) by default.
c = canvas(show_fps=True)
# Get a panel (by default, the one spanning the entire canvas)
# We specify the type of controller we want. Here, we want 2D axes.
panel = c.panel(controller='axes')
# We create a new "marker" visual.
visual = panel.visual('marker')
# We prepare the visual properties. Here, we set the marker positions, colors (RGBA bytes),
# and size (in pixels).
N = 100_000
pos = nr.randn(N, 3)
ms = nr.uniform(low=2, high=35, size=N)
color_values = nr.rand(N)
# Use a built-in colormap
color = colormap(color_values, vmin=0, vmax=1, alpha=.75 * np.ones(N), cmap='viridis')
# Set the visual props.
visual.data('pos', pos)
visual.data('color', color)
visual.data('ms', ms)
# We define an event callback to implement mouse picking
@c.connect
def on_mouse_click(x, y, button, modifiers=()):
# x, y are in pixel coordinates
# First, we find the picked panel
p = c.panel_at(x, y)
if not p:
return
# Then, we transform into the data coordinate system
# Supported coordinate systems:
# target_cds='data' / 'scene' / 'vulkan' / 'framebuffer' / 'window'
xd, yd = p.pick(x, y)
print(f"Pick at ({xd:.4f}, {yd:.4f}), modifiers={modifiers}")
# We create a GUI dialog.
gui = c.gui("Test GUI")
# We add a control, a slider controlling a float
@gui.control("slider_float", "marker size", vmin=.5, vmax=2)
def on_change(value):
# Every time the slider value changes, we update the visual's marker size
visual.data('ms', ms * value)
# NOTE: an upcoming version will support partial updates
# We add another control, a slider controlling an int between 1 and 4, to change the colormap.
# NOTE: an upcoming version will provide a dropdown menu control
cmaps = ['viridis', 'cividis', 'autumn', 'winter']
@gui.control("slider_int", "colormap", vmin=0, vmax=3)
def on_change(value):
# Recompute the colors.
color = colormap(
color_values, vmin=0, vmax=1, alpha=.75 * np.ones(N), cmap=cmaps[value])
# Update the color visual
visual.data('color', color)
# We add a button to regenerate the marker positions
@gui.control("button", "new positions")
def on_change(value):
pos = nr.randn(N, 3)
visual.data('pos', pos)
# We run the main event loop, which will display the canvas until Escape is pressed or the
# window is closed.
# We start a screencast. This will add playback buttons at the bottom right corner.
# NOTE: the video DOESN'T START until you press the play button.
# run(video="screencast.mp4")
run()
