From d125fb2cd3ff50d6b1705b5eeb3eaba68f034d0d Mon Sep 17 00:00:00 2001
From: Jarrod Doyle <thejarroddoyle@gmail.com>
Date: Tue, 27 Aug 2024 07:10:38 +0100
Subject: [PATCH] Parse lightmaps as flat array rather than multidimensional
 array

---
 project/code/LGS/Database/Chunks/WorldRep.cs | 39 +++++++++-----------
 project/code/TMV/Mission.cs                  |  6 +--
 2 files changed, 21 insertions(+), 24 deletions(-)

diff --git a/project/code/LGS/Database/Chunks/WorldRep.cs b/project/code/LGS/Database/Chunks/WorldRep.cs
index 5ea36a7..9423b35 100644
--- a/project/code/LGS/Database/Chunks/WorldRep.cs
+++ b/project/code/LGS/Database/Chunks/WorldRep.cs
@@ -97,45 +97,42 @@ public class WorldRep : IChunk
 
         public struct Lightmap
         {
-            public byte[,,,] Pixels { get; set; }
+            public byte[] Pixels { get; set; }
+
+            public int Layers;
+            public int Width;
+            public int Height;
+            public int Bpp;
 
             public Lightmap(BinaryReader reader, byte width, byte height, uint bitmask, int bytesPerPixel)
             {
                 var count = 1 + BitOperations.PopCount(bitmask);
-                Pixels = new byte[count, height, width, bytesPerPixel];
-                for (var c = 0; c < count; c++)
-                {
-                    for (var y = 0; y < height; y++)
-                    {
-                        for (var x = 0; x < width; x++)
-                        {
-                            for (var b = 0; b < bytesPerPixel; b++)
-                            {
-                                Pixels[c, y, x, b] = reader.ReadByte();
-                            }
-                        }
-                    }
-                }
+                var length = bytesPerPixel * width * height * count;
+                Pixels = reader.ReadBytes(length);
+                Layers = count;
+                Width = width;
+                Height = height;
+                Bpp = bytesPerPixel;
             }
 
             public readonly Vector4 GetPixel(uint layer, uint x, uint y)
             {
-                if (layer >= Pixels.GetLength(0) || x >= Pixels.GetLength(2) || y >= Pixels.GetLength(1))
+                if (layer >= Layers || x >= Width || y >= Height)
                 {
                     return Vector4.Zero;
                 }
 
-                switch (Pixels.GetLength(3))
+                var idx = 0 + x * Bpp + y * Bpp * Width + layer * Bpp * Width * Height;
+                switch (Bpp)
                 {
                     case 1:
-                        var raw1 = Pixels[layer, y, x, 0];
+                        var raw1 = Pixels[idx];
                         return new Vector4(raw1, raw1, raw1, 255) / 255.0f;
                     case 2:
-                        var raw2 = Pixels[layer, y, x, 0] + (Pixels[layer, y, x, 1] << 8);
+                        var raw2 = Pixels[idx] + (Pixels[idx + 1] << 8);
                         return new Vector4(raw2 & 31, (raw2 >> 5) & 31, (raw2 >> 10) & 31, 31) / 31.0f;
                     case 4:
-                        // 4bpp stored as BGRA
-                        return new Vector4(Pixels[layer, y, x, 2], Pixels[layer, y, x, 1], Pixels[layer, y, x, 0], Pixels[layer, y, x, 3]) / 255.0f;
+                        return new Vector4(Pixels[idx + 2], Pixels[idx + 1], Pixels[idx], Pixels[idx + 3]) / 255.0f;
                     default:
                         return Vector4.Zero;
                 }
diff --git a/project/code/TMV/Mission.cs b/project/code/TMV/Mission.cs
index 0345b31..0fc508a 100644
--- a/project/code/TMV/Mission.cs
+++ b/project/code/TMV/Mission.cs
@@ -299,9 +299,9 @@ public partial class Mission : Node3D
 			if (info.cellIndex >= cells.Length) GD.Print($"CellIndex too big: {info.cellIndex}/{cells.Length}");
 			if (info.lightmapIndex >= cells[info.cellIndex].Lightmaps.Length) GD.Print($"LightmapIndex too big: {info.lightmapIndex}/{cells[info.cellIndex].Lightmaps.Length}");
 			var lightmap = cells[info.cellIndex].Lightmaps[info.lightmapIndex];
-			var layers = (uint)lightmap.Pixels.GetLength(0);
-			var height = (uint)lightmap.Pixels.GetLength(1);
-			var width = (uint)lightmap.Pixels.GetLength(2);
+			var layers = (uint)lightmap.Layers;
+			var height = (uint)lightmap.Height;
+			var width = (uint)lightmap.Width;
 			for (uint y = 0; y < height; y++)
 			{
 				for (uint x = 0; x < width; x++)