Improve spotlight cone visualization

Author: kagenocookie

ContentEditor.App/EngineObjects/Components/Light.cs

@@ -13,12 +13,18 @@ public abstract class Light(GameObject gameObject, RszInstance data) : Component
     public bool IsEnabled => AppConfig.Instance.RenderLights.Get();
 
     protected Material? _defaultLightGizmoMaterial;
+    protected Material? _defaultLightGizmoMaterialInner;
 
     protected Material CreateLightMaterial(RenderContext ctx) => _defaultLightGizmoMaterial = ctx.GetMaterialBuilder(BuiltInMaterials.MonoColor, "light")
         .Color("_MainColor", Colors.Lights)
         .Float("_FadeMaxDistance", 250)
         .Blend();
 
+    protected Material CreateLightMaterialInner(RenderContext ctx) => _defaultLightGizmoMaterialInner = ctx.GetMaterialBuilder(BuiltInMaterials.MonoColor, "light_inner")
+        .Color("_MainColor", Colors.Lights with { W = Colors.Lights.W * 0.5f })
+        .Float("_FadeMaxDistance", 250)
+        .Blend();
+
     public abstract GizmoContainer? Update(GizmoContainer? gizmo);
 
     internal override void OnActivate()
@@ -41,16 +47,30 @@ public class SpotLight(GameObject gameObject, RszInstance data) : Light(gameObje
     public override GizmoContainer? Update(GizmoContainer? gizmo)
     {
         gizmo ??= new GizmoContainer(Scene!, this);
-        gizmo.PushMaterial(_defaultLightGizmoMaterial ??= CreateLightMaterial(Scene!.RenderContext));
 
         var fwd = Transform.Forward;
         var radius = RszFieldCache.SpotLight.Radius.GetOrDefault(Data, 0.03f);
         var range = RszFieldCache.SpotLight.ReferenceEffectiveRange.GetOrDefault(Data, 10);
-        var spread = RszFieldCache.SpotLight.Spread.GetOrDefault(Data, 50);
+        var cone = RszFieldCache.SpotLight.Cone.GetOrDefault(Data, 50);
+        var spread = Math.Min(cone, RszFieldCache.SpotLight.Spread.GetOrDefault(Data, 50));
+        // note: I assume spread and cone are for inner and outer cone respectively
+        // inner being full intensity and then gradually 0 intensity until cone angle
+
+        // note2: the angle/distance calculation is probably wrong, very visibly when cone approaches 90
+        // we're offsetting a circle instead of making an arc
+
+        if (Math.Abs(cone - 90f) < 0.1f) cone = 89.9f;
 
         var origin = Transform.Position;
-        var endRadius = MathF.Tan(spread / 180f * MathF.PI) * range;
-        gizmo.Add(new Cone(origin + fwd * radius, 0.001f, origin + fwd * range, endRadius));
+        var endRadiusCone = MathF.Tan(cone / 180f * MathF.PI) * range;
+        var endRadiusSpread = MathF.Tan(spread / 180f * MathF.PI) * range;
+
+        gizmo.PushMaterial(_defaultLightGizmoMaterial ??= CreateLightMaterial(Scene!.RenderContext));
+        gizmo.Add(new Cone(origin + fwd * radius, 0.001f, origin + fwd * range * Math.Sign(endRadiusCone), Math.Abs(endRadiusCone)));
+        gizmo.PopMaterial();
+
+        gizmo.PushMaterial(_defaultLightGizmoMaterialInner ??= CreateLightMaterialInner(Scene!.RenderContext));
+        gizmo.Add(new Cone(origin + fwd * radius, 0.001f, origin + fwd * range * Math.Sign(endRadiusSpread), Math.Abs(endRadiusSpread)));
         gizmo.PopMaterial();
         return gizmo;
     }