update sky renderer to use configurable field of view

Core/Render/OpenGL/Renderers/Legacy/World/Sky/Sphere/SkySphereRenderer.cs

@@ -59,13 +59,6 @@ public void Dispose()
 
     private static mat4 CalculateMvp(RenderInfo renderInfo)
     {
-        // Note that this means we've hard coded the sky to always render
-        // the same regardless of the field of view.
-        float w = renderInfo.Viewport.Width;
-        float h = renderInfo.Viewport.Height;
-        float aspectRatio = w / h;
-        float fovY = OldCamera.FieldOfViewXToY((float)MathHelper.HalfPi, aspectRatio);
-
         // We want the sky sphere to not be touching the NDC edges because
         // we'll be doing some translating which could push it outside of
         // the clipping box. Therefore we shrink the unit sphere from r = 1
@@ -83,7 +76,8 @@ private static mat4 CalculateMvp(RenderInfo renderInfo)
 
         // Our projection far plane only goes as far as the scaled sphere
         // radius.
-        mat4 projection = mat4.PerspectiveFov(fovY, w, h, 0.0f, 0.5f);
+        var fovInfo = Renderer.GetFieldOfViewInfo(renderInfo);
+        mat4 projection = mat4.PerspectiveFov(fovInfo.FovY, fovInfo.Width, fovInfo.Height, 0.0f, 0.5f);
 
         return projection * view * model;
     }

Core/Render/Renderer.cs

@@ -26,6 +26,8 @@
 
 namespace Helion.Render;
 
+public record struct FieldOfViewInfo(float Width, float Height, float FovY);
+
 public class Renderer : IDisposable
 {
     const float ZNearMin = 0.2f;
@@ -124,18 +126,23 @@ public static Vec3F GetColorMix(Entity viewerEntity, OldCamera camera)
 
     public static mat4 CalculateMvpMatrix(RenderInfo renderInfo, bool onlyXY = false)
     {
-        float w = renderInfo.Viewport.Width;
-        float h = renderInfo.Viewport.Height * 0.825f;
-        // Default FOV is 63.2. Config default is 90 so we need to convert. (90 - 63.2 = 26.8).
-        float fovY = (float)MathHelper.ToRadians(renderInfo.Config.FieldOfView - 26.8);
-
+        var fovInfo = GetFieldOfViewInfo(renderInfo);
         mat4 model = mat4.Identity;
         mat4 view = renderInfo.Camera.CalculateViewMatrix(onlyXY);
 
-        mat4 projection = mat4.PerspectiveFov(fovY, w, h, GetZNear(renderInfo), 65536.0f);
+        mat4 projection = mat4.PerspectiveFov(fovInfo.FovY, fovInfo.Width, fovInfo.Height, GetZNear(renderInfo), 65536.0f);
         return projection * view * model;
     }
 
+    public static FieldOfViewInfo GetFieldOfViewInfo(RenderInfo renderInfo)
+    {
+        float w = renderInfo.Viewport.Width;
+        float h = renderInfo.Viewport.Height * 0.825f;
+        // Default FOV is 63.2. Config default is 90 so we need to convert. (90 - 63.2 = 26.8).
+        float fovY = (float)MathHelper.ToRadians(renderInfo.Config.FieldOfView - 26.8);
+        return new(w, h, fovY);
+    }
+
     private static float GetZNear(RenderInfo renderInfo)
     {
         // Optimially this should be handled in the shader. Setting this variable and using it for a low zNear is good enough for now.