Add sun shadows (planet lighting stage 2) (#35145)

* Implements a Dynamic Lighting System on maps. * Edit: the night should be a little bit brighter and blue now. * Major edit: everything must be done on the client side now, with certain datafield replicated. Changes were outlined in the salvage to accommodate the new lighting system. * Edit: The offset is now serverside, this makes the time accurate in all situations. * Removing ununsed import * Minor tweaks * Tweak in time precision * Minor tweak + Unused import removed * Edit: apparently RealTime is better for what I'm looking for * Fix: Now the time is calculated correctly. * Minor tweaks * Adds condition for when the light should be updated * Add planet lighting * she * close-ish * c * bittersweat * Fixes * Revert "Merge branch '22719' into 2024-09-29-planet-lighting" This reverts commit 9f2785bb16aee47d794aa3eed8ae15004f97fc35, reversing changes made to 19649c07a5fb625423e08fc18d91c9cb101daa86. * Europa and day-night * weh * rooves working * Clean * Remove Europa * Fixes * fix * Update * Fix caves * Update for engine * Add sun shadows (planet lighting v2) For now mostly targeting walls and having the shadows change over time. Got the basic proof-of-concept working just needs a hell of a lot of polish. * Documentation * a * Fixes * Move blur to an overlay * Slughands * Fixes * Apply RoofOverlay per-grid not per-map * Fix light render scales * sangas * Juice it a bit * Better angle * Fixes * Add color support * Rounding bandaid * Wehs * Better * Remember I forgot to do this when writing docs --------- Co-authored-by: DoutorWhite <thedoctorwhite@gmail.com>
2025-03-08 16:07:42 +11:00
parent db96cc7881
commit f51b9bc86e
17 changed files with 466 additions and 6 deletions
--- a/Content.Shared/Light/EntitySystems/SharedLightCycleSystem.cs
+++ b/Content.Shared/Light/EntitySystems/SharedLightCycleSystem.cs
@@ -0,0 +1,134 @@
+using Content.Shared.Light.Components;
+using Robust.Shared.Map.Components;
+
+namespace Content.Shared.Light.EntitySystems;
+
+public abstract class SharedLightCycleSystem : EntitySystem
+{
+    public override void Initialize()
+    {
+        base.Initialize();
+        SubscribeLocalEvent<LightCycleComponent, MapInitEvent>(OnCycleMapInit);
+        SubscribeLocalEvent<LightCycleComponent, ComponentShutdown>(OnCycleShutdown);
+    }
+
+    protected virtual void OnCycleMapInit(Entity<LightCycleComponent> ent, ref MapInitEvent args)
+    {
+        if (TryComp(ent.Owner, out MapLightComponent? mapLight))
+        {
+            ent.Comp.OriginalColor = mapLight.AmbientLightColor;
+            Dirty(ent);
+        }
+    }
+
+    private void OnCycleShutdown(Entity<LightCycleComponent> ent, ref ComponentShutdown args)
+    {
+        if (TryComp(ent.Owner, out MapLightComponent? mapLight))
+        {
+            mapLight.AmbientLightColor = ent.Comp.OriginalColor;
+            Dirty(ent.Owner, mapLight);
+        }
+    }
+
+    public void SetOffset(Entity<LightCycleComponent> entity, TimeSpan offset)
+    {
+        entity.Comp.Offset = offset;
+        var ev = new LightCycleOffsetEvent(offset);
+
+        RaiseLocalEvent(entity, ref ev);
+        Dirty(entity);
+    }
+
+    public static Color GetColor(Entity<LightCycleComponent> cycle, Color color, float time)
+    {
+        if (cycle.Comp.Enabled)
+        {
+            var lightLevel = CalculateLightLevel(cycle.Comp, time);
+            var colorLevel = CalculateColorLevel(cycle.Comp, time);
+            return new Color(
+                (byte)Math.Min(255, color.RByte * colorLevel.R * lightLevel),
+                (byte)Math.Min(255, color.GByte * colorLevel.G * lightLevel),
+                (byte)Math.Min(255, color.BByte * colorLevel.B * lightLevel)
+            );
+        }
+
+        return color;
+    }
+
+    /// <summary>
+    /// Calculates light intensity as a function of time.
+    /// </summary>
+    public static double CalculateLightLevel(LightCycleComponent comp, float time)
+    {
+        var waveLength = MathF.Max(1, (float) comp.Duration.TotalSeconds);
+        var crest = MathF.Max(0f, comp.MaxLightLevel);
+        var shift = MathF.Max(0f, comp.MinLightLevel);
+        return Math.Min(comp.ClipLight, CalculateCurve(time, waveLength, crest, shift, 6));
+    }
+
+    /// <summary>
+    /// It is important to note that each color must have a different exponent, to modify how early or late one color should stand out in relation to another.
+    /// This "simulates" what the atmosphere does and is what generates the effect of dawn and dusk.
+    /// The blue component must be a cosine function with half period, so that its minimum is at dawn and dusk, generating the "warm" color corresponding to these periods.
+    /// As you can see in the values, the maximums of the function serve more to define the curve behavior,
+    /// they must be "clipped" so as not to distort the original color of the lighting. In practice, the maximum values, in fact, are the clip thresholds.
+    /// </summary>
+    public static Color CalculateColorLevel(LightCycleComponent comp, float time)
+    {
+        var waveLength = MathF.Max(1f, (float) comp.Duration.TotalSeconds);
+
+        var red = MathF.Min(comp.ClipLevel.R,
+            CalculateCurve(time,
+                waveLength,
+                MathF.Max(0f, comp.MaxLevel.R),
+                MathF.Max(0f, comp.MinLevel.R),
+                4f));
+
+        var green = MathF.Min(comp.ClipLevel.G,
+            CalculateCurve(time,
+                waveLength,
+                MathF.Max(0f, comp.MaxLevel.G),
+                MathF.Max(0f, comp.MinLevel.G),
+                10f));
+
+        var blue = MathF.Min(comp.ClipLevel.B,
+            CalculateCurve(time,
+                waveLength / 2f,
+                MathF.Max(0f, comp.MaxLevel.B),
+                MathF.Max(0f, comp.MinLevel.B),
+                2,
+                waveLength / 4f));
+
+        return new Color(red, green, blue);
+    }
+
+    /// <summary>
+    /// Generates a sinusoidal curve as a function of x (time). The other parameters serve to adjust the behavior of the curve.
+    /// </summary>
+    /// <param name="x"> It corresponds to the independent variable of the function, which in the context of this algorithm is the current time. </param>
+    /// <param name="waveLength"> It's the wavelength of the function, it can be said to be the total duration of the light cycle. </param>
+    /// <param name="crest"> It's the maximum point of the function, where it will have its greatest value. </param>
+    /// <param name="shift"> It's the vertical displacement of the function, in practice it corresponds to the minimum value of the function. </param>
+    /// <param name="exponent"> It is the exponent of the sine, serves to "flatten" the function close to its minimum points and make it "steeper" close to its maximum. </param>
+    /// <param name="phase"> It changes the phase of the wave, like a "horizontal shift". It is important to transform the sinusoidal function into cosine, when necessary. </param>
+    /// <returns> The result of the function. </returns>
+    public static float CalculateCurve(float x,
+        float waveLength,
+        float crest,
+        float shift,
+        float exponent,
+        float phase = 0)
+    {
+        var sen = MathF.Pow(MathF.Sin((MathF.PI * (phase + x)) / waveLength), exponent);
+        return (crest - shift) * sen + shift;
+    }
+}
+
+/// <summary>
+/// Raised when the offset on <see cref="LightCycleComponent"/> changes.
+/// </summary>
+[ByRefEvent]
+public record struct LightCycleOffsetEvent(TimeSpan Offset)
+{
+    public readonly TimeSpan Offset = Offset;
+}