Add support for BC1/2/3 decompression (for 3D textures) (#2987)

* Add support for BC1/2/3 decompression (for 3D textures)

* Optimize and clean up

* Unsafe not needed here

* Fix alpha value interpolation when a0 <= a1

3 files changed, 49 insertions, 18 deletions

diff --git a/Ryujinx.Graphics.Gpu/GpuContext.cs b/Ryujinx.Graphics.Gpu/GpuContext.cs
index 5c9af383..ddc95b2c 100644
--- a/Ryujinx.Graphics.Gpu/GpuContext.cs
+++ b/Ryujinx.Graphics.Gpu/GpuContext.cs
@@ -78,14 +78,27 @@ namespace Ryujinx.Graphics.Gpu
         /// <summary>
         /// Host hardware capabilities.
         /// </summary>
-        internal Capabilities Capabilities => _caps.Value;
+        internal ref Capabilities Capabilities
+        {
+            get
+            {
+                if (!_capsLoaded)
+                {
+                    _caps = Renderer.GetCapabilities();
+                    _capsLoaded = true;
+                }
+
+                return ref _caps;
+            }
+        }
 
         /// <summary>
         /// Event for signalling shader cache loading progress.
         /// </summary>
         public event Action<ShaderCacheState, int, int> ShaderCacheStateChanged;
 
-        private readonly Lazy<Capabilities> _caps;
+        private bool _capsLoaded;
+        private Capabilities _caps;
         private Thread _gpuThread;
 
         /// <summary>
@@ -110,8 +123,6 @@ namespace Ryujinx.Graphics.Gpu
             DeferredActions = new Queue<Action>();
 
             PhysicalMemoryRegistry = new ConcurrentDictionary<long, PhysicalMemory>();
-
-            _caps = new Lazy<Capabilities>(Renderer.GetCapabilities);
         }
 
         /// <summary>
diff --git a/Ryujinx.Graphics.Gpu/Image/Texture.cs b/Ryujinx.Graphics.Gpu/Image/Texture.cs
index b2fa15a2..e1f00606 100644
--- a/Ryujinx.Graphics.Gpu/Image/Texture.cs
+++ b/Ryujinx.Graphics.Gpu/Image/Texture.cs
@@ -834,13 +834,31 @@ namespace Ryujinx.Graphics.Gpu.Image
             {
                 data = PixelConverter.ConvertR4G4ToR4G4B4A4(data);
             }
-            else if (Target == Target.Texture3D && Format.IsBc4())
+            else if (!_context.Capabilities.Supports3DTextureCompression && Target == Target.Texture3D)
             {
-                data = BCnDecoder.DecodeBC4(data, width, height, depth, levels, layers, Info.FormatInfo.Format == Format.Bc4Snorm);
-            }
-            else if (Target == Target.Texture3D && Format.IsBc5())
-            {
-                data = BCnDecoder.DecodeBC5(data, width, height, depth, levels, layers, Info.FormatInfo.Format == Format.Bc5Snorm);
+                switch (Format)
+                {
+                    case Format.Bc1RgbaSrgb:
+                    case Format.Bc1RgbaUnorm:
+                        data = BCnDecoder.DecodeBC1(data, width, height, depth, levels, layers);
+                        break;
+                    case Format.Bc2Srgb:
+                    case Format.Bc2Unorm:
+                        data = BCnDecoder.DecodeBC2(data, width, height, depth, levels, layers);
+                        break;
+                    case Format.Bc3Srgb:
+                    case Format.Bc3Unorm:
+                        data = BCnDecoder.DecodeBC3(data, width, height, depth, levels, layers);
+                        break;
+                    case Format.Bc4Snorm:
+                    case Format.Bc4Unorm:
+                        data = BCnDecoder.DecodeBC4(data, width, height, depth, levels, layers, Format == Format.Bc4Snorm);
+                        break;
+                    case Format.Bc5Snorm:
+                    case Format.Bc5Unorm:
+                        data = BCnDecoder.DecodeBC5(data, width, height, depth, levels, layers, Format == Format.Bc5Snorm);
+                        break;
+                }
             }
 
             return data;
diff --git a/Ryujinx.Graphics.Gpu/Image/TextureCompatibility.cs b/Ryujinx.Graphics.Gpu/Image/TextureCompatibility.cs
index 0461a81f..188e1e09 100644
--- a/Ryujinx.Graphics.Gpu/Image/TextureCompatibility.cs
+++ b/Ryujinx.Graphics.Gpu/Image/TextureCompatibility.cs
@@ -14,9 +14,6 @@ namespace Ryujinx.Graphics.Gpu.Image
         private enum FormatClass
         {
             Unclassified,
-            BCn64,
-            BCn128,
-            Bc1Rgb,
             Bc1Rgba,
             Bc2,
             Bc3,
@@ -88,13 +85,21 @@ namespace Ryujinx.Graphics.Gpu.Image
                 return new FormatInfo(Format.R4G4B4A4Unorm, 1, 1, 2, 4);
             }
 
-            if (info.Target == Target.Texture3D)
+            if (!caps.Supports3DTextureCompression && info.Target == Target.Texture3D)
             {
-                // The host API does not support 3D BC4/BC5 compressed formats.
+                // The host API does not support 3D compressed formats.
                 // We assume software decompression will be done for those textures,
                 // and so we adjust the format here to match the decompressor output.
                 switch (info.FormatInfo.Format)
                 {
+                    case Format.Bc1RgbaSrgb:
+                    case Format.Bc2Srgb:
+                    case Format.Bc3Srgb:
+                        return new FormatInfo(Format.R8G8B8A8Srgb, 1, 1, 4, 4);
+                    case Format.Bc1RgbaUnorm:
+                    case Format.Bc2Unorm:
+                    case Format.Bc3Unorm:
+                        return new FormatInfo(Format.R8G8B8A8Unorm, 1, 1, 4, 4);
                     case Format.Bc4Unorm:
                         return new FormatInfo(Format.R8Unorm, 1, 1, 1, 1);
                     case Format.Bc4Snorm:
@@ -749,9 +754,6 @@ namespace Ryujinx.Graphics.Gpu.Image
         {
             switch (format)
             {
-                case Format.Bc1RgbSrgb:
-                case Format.Bc1RgbUnorm:
-                    return FormatClass.Bc1Rgb;
                 case Format.Bc1RgbaSrgb:
                 case Format.Bc1RgbaUnorm:
                     return FormatClass.Bc1Rgba;