Ping-Pong Band

Move a soft band left and right using sin(u_time).

Overview

• Implement a horizontal gradient using UV as the factor.

Learning Objectives

• Animate with u_time

Prerequisites

• uv-coordinates

Inputs

• float u_time — Time in seconds.

Key Concepts

• A horizontal gradient uses a 0-1 factor (usually UV) to blend colors.

float t = vUv.x;
vec3 color = vec3(t);

• Keep the factor inside [0,1].

t = clamp(t, 0.0, 1.0);

How To Implement (Step-by-step)

• Set factor: t = vUv.x.
• Map t to a color (grayscale or mix).
• Output gl_FragColor with alpha=1.

Self-check

• Does it compile without errors?
• Does the output match the goal?
• Are key values kept in [0,1]?

Common Mistakes

• Clamp t into [0,1] when needed.
• Make sure edge0 < edge1 for smoothstep().