Modulation

Modulation is one of the most powerful techniques in Hydra. It uses the colors of one source to distort the geometry of another.

How modulation works

When modulating:

• The modulator’s red channel → offset along X
• The modulator’s green channel → offset along Y
• Bright areas are distorted more

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modulate() — Basic modulation

source.modulate(texture, amount)

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modulateScale() — Scale modulation

Changes the scale of different parts of the image.

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modulateRotate() — Rotation modulation

Applies a different amount of rotation to different parts of the image.

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modulateHue() — Hue modulation

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modulateKaleid() — Kaleidoscope modulation

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modulateRepeat() — Repetition modulation

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modulatePixelate()

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Complex examples

Layered modulation

Self-modulation (feedback)

Cross modulation

Combining with color

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Modulation tips

1. Start with small values (0.1-0.3)
2. Use noise() as the modulator for organic distortions
3. Combine with color effects
4. Animate the intensity: () => Math.sin(time) * 0.3