Point Visual¶

The Point visual renders circular, borderless filled discs at 2D or 3D positions. It provides a simple and efficient way to visualize large sets of unstyled points.

Overview¶

Renders filled circular discs
Per-vertex: position, color, size
No border, shape, or texture

When to use¶

Use the point visual when:

You need basic, fast scatter plots with custom colors and sizes
You don’t need symbolic shapes or outlines (use Marker for that)
You want simple 3D point clouds with minimal overhead (but more overhead than Pixel)

Attributes¶

Per-item¶

Attribute	Type	Description
`position`	`(N, 3) float32`	3D positions in NDC space
`color`	`(N, 4) uint8`	Per-point RGBA color
`size`	`(N,) float32`	Per-point diameter in pixels

All attributes are per-vertex and required.

Example¶

import numpy as np

import datoviz as dvz


def generate_data():
    grid_x = 16
    grid_y = 12
    N = grid_x * grid_y

    # Grid coordinates in [-1, 1]
    x = np.linspace(-1, 1, grid_x)
    y = np.linspace(-1, 1, grid_y)
    X, Y = np.meshgrid(x, y)
    x_flat = X.flatten()
    y_flat = Y.flatten()
    z_flat = np.zeros_like(x_flat)

    positions = np.stack([x_flat, y_flat, z_flat], axis=1).astype(np.float32)
    positions *= 0.90  # margin

    # Hue along x-axis
    hue = (x_flat + 1) / 2
    colors = dvz.cmap('hsv', hue)

    # Size: exponential growth from 10px to 50px along y-axis
    y_norm = (y_flat + 1) / 2
    sizes = 10 * 4.0**y_norm
    sizes = sizes.astype(np.float32)

    return N, positions, colors, sizes


N, position, color, size = generate_data()

app = dvz.App()
figure = app.figure()
panel = figure.panel()
panzoom = panel.panzoom()

visual = app.point(position=position, color=color, size=size)
panel.add(visual)

app.run()
app.destroy()

Summary¶

The point visual is the fastest way to render a large number of colored, sized circular points.

✔️ Efficient for scatter plots and point clouds
✔️ Fully GPU-accelerated
❌ No support for borders, shapes, or textures (use Marker instead)