From cd47600e57de0c92b24509f28929239d7a1518ac Mon Sep 17 00:00:00 2001
From: gdk <gab.dark.100@gmail.com>
Date: Sat, 9 Nov 2019 21:26:29 -0300
Subject: [PATCH] Check for ASTC support on the list of supported compressed
 formats

---
 Ryujinx.Graphics.OpenGL/HwCapabilities.cs | 67 ++++++++++++++++++++++-
 1 file changed, 66 insertions(+), 1 deletion(-)

diff --git a/Ryujinx.Graphics.OpenGL/HwCapabilities.cs b/Ryujinx.Graphics.OpenGL/HwCapabilities.cs
index f958946e7c..883542d6c0 100644
--- a/Ryujinx.Graphics.OpenGL/HwCapabilities.cs
+++ b/Ryujinx.Graphics.OpenGL/HwCapabilities.cs
@@ -5,10 +5,75 @@ namespace Ryujinx.Graphics.OpenGL
 {
     static class HwCapabilities
     {
-        private static Lazy<bool> _astcCompression = new Lazy<bool>(() => HasExtension("GL_KHR_texture_compression_astc_ldr"));
+        private static Lazy<bool> _astcCompression = new Lazy<bool>(SupportsAstcCompressionImpl);
 
         public static bool SupportsAstcCompression => _astcCompression.Value;
 
+        private static bool SupportsAstcCompressionImpl()
+        {
+            // The NVIDIA driver has software decompression support for ASTC textures,
+            // but the extension is not exposed, so we check the list of compressed
+            // formats too, since the support is indicated there.
+            return SupportsAnyAstcFormat() || HasExtension("GL_KHR_texture_compression_astc_ldr");
+        }
+
+        private static bool SupportsAnyAstcFormat()
+        {
+            int formatsCount = GL.GetInteger(GetPName.NumCompressedTextureFormats);
+
+            int[] formats = new int[formatsCount];
+
+            GL.GetInteger(GetPName.CompressedTextureFormats, formats);
+
+            foreach (int format in formats)
+            {
+                if (IsAstcFormat(format))
+                {
+                    return true;
+                }
+            }
+
+            return false;
+        }
+
+        private static bool IsAstcFormat(int format)
+        {
+            switch ((All)format)
+            {
+                case All.CompressedRgbaAstc4X4Khr:
+                case All.CompressedRgbaAstc5X4Khr:
+                case All.CompressedRgbaAstc5X5Khr:
+                case All.CompressedRgbaAstc6X5Khr:
+                case All.CompressedRgbaAstc6X6Khr:
+                case All.CompressedRgbaAstc8X5Khr:
+                case All.CompressedRgbaAstc8X6Khr:
+                case All.CompressedRgbaAstc8X8Khr:
+                case All.CompressedRgbaAstc10X5Khr:
+                case All.CompressedRgbaAstc10X6Khr:
+                case All.CompressedRgbaAstc10X8Khr:
+                case All.CompressedRgbaAstc10X10Khr:
+                case All.CompressedRgbaAstc12X10Khr:
+                case All.CompressedRgbaAstc12X12Khr:
+                case All.CompressedSrgb8Alpha8Astc4X4Khr:
+                case All.CompressedSrgb8Alpha8Astc5X4Khr:
+                case All.CompressedSrgb8Alpha8Astc5X5Khr:
+                case All.CompressedSrgb8Alpha8Astc6X5Khr:
+                case All.CompressedSrgb8Alpha8Astc6X6Khr:
+                case All.CompressedSrgb8Alpha8Astc8X5Khr:
+                case All.CompressedSrgb8Alpha8Astc8X6Khr:
+                case All.CompressedSrgb8Alpha8Astc8X8Khr:
+                case All.CompressedSrgb8Alpha8Astc10X5Khr:
+                case All.CompressedSrgb8Alpha8Astc10X6Khr:
+                case All.CompressedSrgb8Alpha8Astc10X8Khr:
+                case All.CompressedSrgb8Alpha8Astc10X10Khr:
+                case All.CompressedSrgb8Alpha8Astc12X10Khr:
+                case All.CompressedSrgb8Alpha8Astc12X12Khr:
+                    return true;
+            }
+
+            return false;
+        }
+
         private static bool HasExtension(string name)
         {
             int numExtensions = GL.GetInteger(GetPName.NumExtensions);