eeeb6db290
GravityField is now the band term U(eps, inner, outer) (C4 smoothstep fade, closed form and a series for tau > 1). WellTree is built once per Zone from the orbit tree: node terms, reach, support, the pruned Force/Potential walk and PullAround (rails). Zone.GetHeight/GetForce/PeriodAround delegate to it; WellReference, _wellOn, _strengths, Strength() and DrawAhead.Well are gone; GravityLowering and the shader template take the flat term list; HeightExaggeration halves to 2.0491803. Does not pass yet: Gravity.cginc is not regenerated and PotentialOwnerTests/OrbitsFromFieldTests still spell the old law. Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
85 lines
3.8 KiB
C#
85 lines
3.8 KiB
C#
using System.Runtime.InteropServices;
|
|
using UnityEngine;
|
|
|
|
/// <summary>
|
|
/// The renderer's lowering of the zone's potential (aetheria-gravity, cut grid-lowering). Zone.GetHeight owns the drawn
|
|
/// height: this hands its inputs (each term's position, strength, softening, band edges and reference, and the
|
|
/// exaggeration) to Assets/Shaders/Gravity.cginc, which sums them per texel, and makes the one quad that carries the sum into every
|
|
/// camera that culls layer 9. Nothing here decides a height.
|
|
/// </summary>
|
|
public static class GravityLowering
|
|
{
|
|
/// <summary>The layer the gravity cameras cull; nothing but the run-time field sits on it.</summary>
|
|
public const int FieldLayer = 9;
|
|
/// <summary>The quad's side in u: larger than any zone (10000) plus any view (4096); texels outside a camera cost nothing.</summary>
|
|
public const float FieldExtent = 100000f;
|
|
|
|
// Mirrors the term record of Gravity.cginc: float2 position, strength, softening, inner, outer, reference.
|
|
[StructLayout(LayoutKind.Sequential)]
|
|
struct TermRecord
|
|
{
|
|
public Vector2 Position;
|
|
public float Strength;
|
|
public float Softening;
|
|
public float Inner;
|
|
public float Outer;
|
|
public float Reference;
|
|
}
|
|
|
|
static readonly int Stride = Marshal.SizeOf<TermRecord>();
|
|
static readonly int WellsId = Shader.PropertyToID("_GravityWells");
|
|
static readonly int CountId = Shader.PropertyToID("_GravityWellCount");
|
|
static readonly int ExaggerationId = Shader.PropertyToID("_HeightExaggeration");
|
|
static TermRecord[] _records = new TermRecord[0];
|
|
|
|
/// <summary>
|
|
/// Fills one record per term of the zone's WellTree (a null zone has none) and sets the shader globals. The buffer is
|
|
/// the caller's, (re)allocated to the term count (at least one, so the global is always bound). Terms are lowered at
|
|
/// their node's rail at the drawn time (DrawAhead.Time), the same T the planets and a ship's ride height use.
|
|
/// </summary>
|
|
public static void Lower(Zone zone, float lead, ref ComputeBuffer wells)
|
|
{
|
|
var count = zone?.Wells.Terms.Count ?? 0;
|
|
var capacity = Mathf.Max(count, 1);
|
|
if (wells == null || wells.count != capacity)
|
|
{
|
|
wells?.Release();
|
|
wells = new ComputeBuffer(capacity, Stride);
|
|
}
|
|
|
|
if (_records.Length != capacity) _records = new TermRecord[capacity];
|
|
for (var t = 0; t < count; t++)
|
|
{
|
|
var term = zone.Wells.Terms[t];
|
|
var at = DrawAhead.Orbit(zone, term.Node, lead);
|
|
_records[t] = new TermRecord
|
|
{
|
|
Position = new Vector2(at.x, at.y),
|
|
Strength = term.Strength,
|
|
Softening = term.Softening,
|
|
Inner = term.Inner,
|
|
Outer = term.Outer,
|
|
Reference = term.Reference
|
|
};
|
|
}
|
|
wells.SetData(_records);
|
|
|
|
Shader.SetGlobalBuffer(WellsId, wells);
|
|
Shader.SetGlobalInt(CountId, count);
|
|
Shader.SetGlobalFloat(ExaggerationId, zone?.Settings.HeightExaggeration ?? 1f);
|
|
}
|
|
|
|
/// <summary>The one quad of the field: flat in xz at y 0 on layer 9, drawn with the Gravity Field material.</summary>
|
|
public static GameObject CreateField(Material material)
|
|
{
|
|
var field = new GameObject("Gravity Field") { layer = FieldLayer };
|
|
field.transform.rotation = Quaternion.Euler(90f, 0f, 0f);
|
|
field.transform.localScale = FieldExtent * Vector3.one;
|
|
field.AddComponent<MeshFilter>().sharedMesh = Resources.GetBuiltinResource<Mesh>("Quad.fbx");
|
|
var renderer = field.AddComponent<MeshRenderer>();
|
|
renderer.sharedMaterial = material;
|
|
renderer.shadowCastingMode = UnityEngine.Rendering.ShadowCastingMode.Off;
|
|
renderer.receiveShadows = false;
|
|
return field;
|
|
}
|
|
}
|