feat(viewer): starfield backdrop for deep-space context

1 files changed, 21 insertions, 1 deletions

diff --git a/src/SomhairlesDream.Frontend/App.fs b/src/SomhairlesDream.Frontend/App.fs
index 72d1be2..2aa78eb 100644
--- a/src/SomhairlesDream.Frontend/App.fs
+++ b/src/SomhairlesDream.Frontend/App.fs
@@ -210,7 +210,7 @@ let frameObject (view: ViewState) (node: ThreeNode) =
             camera.position.set(dirX / norm * distance, dirY / norm * distance, dirZ / norm * distance)
             |> ignore
             camera.near <- max 1.0 (distance * 0.05)
-            camera.far <- distance + longest * 3.0
+            camera.far <- max 700.0 (distance + longest * 3.0)
             camera.lookAt(0.0, 0.0, 0.0)
             camera.updateProjectionMatrix ()
 
@@ -277,6 +277,26 @@ let initializeView () =
     let bounceLight = createHemisphereLight("#3d4a56", "#141a1e", 0.9)
     scene.add(bounceLight)
 
+    // Starfield: gives deep-space context so the vehicle reads as a ship in
+    // the void instead of a model on a grey stage.
+    let starCount = 2600
+    let starPositions = Array.zeroCreate (starCount * 3)
+    let starRng = System.Random(4242)
+
+    for index in 0 .. starCount - 1 do
+        let theta = starRng.NextDouble() * 2.0 * System.Math.PI
+        let phi = System.Math.Acos(2.0 * starRng.NextDouble() - 1.0)
+        let radius = 260.0 + starRng.NextDouble() * 90.0
+        starPositions.[index * 3] <- radius * System.Math.Sin(phi) * System.Math.Cos(theta)
+        starPositions.[index * 3 + 1] <- radius * System.Math.Cos(phi)
+        starPositions.[index * 3 + 2] <- radius * System.Math.Sin(phi) * System.Math.Sin(theta)
+
+    let starGeometry = createBufferGeometry ()
+    starGeometry.setAttribute("position", createFloat32BufferAttribute(starPositions, 3)) |> ignore
+    let starMaterial = createPointsMaterial "#c9d6e6" 1.7 0.9
+    let stars = createPoints starGeometry starMaterial
+    scene.add(stars)
+
     // Coordinate ground grid so the model reads as anchored in a workspace
     // instead of floating in a void.
     let grid = createGridHelper (24.0, 48, "#5a4a2a", "#2a2f33")