From e27ade5aee71eb6e801876c0c6cde7d238a23d1e Mon Sep 17 00:00:00 2001
From: riperiperi <rhy3756547@hotmail.com>
Date: Thu, 27 Jun 2024 00:20:00 +0100
Subject: [PATCH] Add constrained border colours to samplers (#26)

---
 src/Ryujinx.Graphics.Metal/Sampler.cs | 35 ++++++++++++++++++++++++++-
 1 file changed, 34 insertions(+), 1 deletion(-)

diff --git a/src/Ryujinx.Graphics.Metal/Sampler.cs b/src/Ryujinx.Graphics.Metal/Sampler.cs
index 9f8ae74b4..7930627d4 100644
--- a/src/Ryujinx.Graphics.Metal/Sampler.cs
+++ b/src/Ryujinx.Graphics.Metal/Sampler.cs
@@ -14,9 +14,11 @@ namespace Ryujinx.Graphics.Metal
         {
             (MTLSamplerMinMagFilter minFilter, MTLSamplerMipFilter mipFilter) = info.MinFilter.Convert();
 
+            MTLSamplerBorderColor borderColor = GetConstrainedBorderColor(info.BorderColor, out _);
+
             var samplerState = device.NewSamplerState(new MTLSamplerDescriptor
             {
-                BorderColor = MTLSamplerBorderColor.TransparentBlack,
+                BorderColor = borderColor,
                 MinFilter = minFilter,
                 MagFilter = info.MagFilter.Convert(),
                 MipFilter = mipFilter,
@@ -39,6 +41,37 @@ namespace Ryujinx.Graphics.Metal
             _mtlSamplerState = samplerState;
         }
 
+        private static MTLSamplerBorderColor GetConstrainedBorderColor(ColorF arbitraryBorderColor, out bool cantConstrain)
+        {
+            float r = arbitraryBorderColor.Red;
+            float g = arbitraryBorderColor.Green;
+            float b = arbitraryBorderColor.Blue;
+            float a = arbitraryBorderColor.Alpha;
+
+            if (r == 0f && g == 0f && b == 0f)
+            {
+                if (a == 1f)
+                {
+                    cantConstrain = false;
+                    return MTLSamplerBorderColor.OpaqueBlack;
+                }
+
+                if (a == 0f)
+                {
+                    cantConstrain = false;
+                    return MTLSamplerBorderColor.TransparentBlack;
+                }
+            }
+            else if (r == 1f && g == 1f && b == 1f && a == 1f)
+            {
+                cantConstrain = false;
+                return MTLSamplerBorderColor.OpaqueWhite;
+            }
+
+            cantConstrain = true;
+            return MTLSamplerBorderColor.OpaqueBlack;
+        }
+
         public MTLSamplerState GetSampler()
         {
             return _mtlSamplerState;