kaiju/Assets/Util/SpectreVfxSdfBinder.cs

using UnityEngine;
using UnityEngine.VFX;
using UnityEngine.VFX.Utility;

namespace Assets.WasapiAudio.Scripts.Unity
{
    [AddComponentMenu("VFX/Property Binders/Spectre - VFX SDF Binder")]
    [VFXBinder("Audio/Audio Spectrum Data to 3d SDF AttributeMap")]
    public class SpectreVfxSdfBinder : VfxAudioVisualizationEffect
    {
        [VFXPropertyBinding("System.UInt32"), SerializeField]
        protected ExposedProperty SpectrumSizeParameter = "SpectrumSize";

        [VFXPropertyBinding("UnityEngine.Texture3D"), SerializeField]
        protected ExposedProperty SpectrumDataTextureParameter = "SpectrumDataTexture";

        private Texture3D _texture;
        private Color[] _colorCache;

        private int z = 0;

        private void UpdateTexture()
        {
            if (_texture == null)
            {
                _texture = new Texture3D(SpectrumSize * 2, SpectrumSize * 2, SpectrumSize * 2, TextureFormat.RFloat, false);
                _texture.name = $"AudioSpectrumDataSDF{SpectrumSize}";
                _colorCache = new Color[
                    SpectrumSize * 2 *
                    SpectrumSize * 2 *
                    SpectrumSize * 2
                ];
            }

            var spectrumData = GetSpectrumData();

            // go from 0 to end of spectrum
            for (int x = 0; x < SpectrumSize; x++) {
                float height = spectrumData[x] * SpectrumSize * 2;

                // go from 0 to double the spectrum height
                for (int y = 0; y < SpectrumSize * 2; y++) {
                    float distance = (y - height);

                    var z_part = z * (SpectrumSize * 2 * SpectrumSize * 2);
                    var y_part = y * SpectrumSize * 2;

                    _colorCache[z_part + y_part + (SpectrumSize + x)] = new Color(distance, 0, 0, 0);
                    _colorCache[z_part + y_part + (SpectrumSize - (x + 1))] = new Color(distance, 0, 0, 0);
                }
            }

            z = (z + 1) % (SpectrumSize * 2);

            // Debug.Log($"{z}");

            _texture.SetPixels(_colorCache);
            _texture.Apply();
        }

        public override void UpdateBinding(VisualEffect component)
        {
            base.UpdateBinding(component);
            UpdateTexture();
            component.SetUInt(SpectrumSizeParameter, (uint) SpectrumSize);
            component.SetTexture(SpectrumDataTextureParameter, _texture);
        }

        public override string ToString()
        {
            return "Audio Spectrum Data";
        }
    }
}