GS/HW: Minor shader optimization.

Use saturate instead of min max, saturate is faster than min max.
PCSX2 · Apr 21, 2024 · 7dd7345 · 7dd7345
1 parent 7e1900a
commit 7dd7345
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Showing 3 changed files with 6 additions and 9 deletions.
diff --git a/bin/resources/shaders/dx11/tfx.fx b/bin/resources/shaders/dx11/tfx.fx
@@ -898,7 +898,7 @@ void ps_blend(inout float4 Color, inout float4 As_rgba, float2 pos_xy)
 		// We shouldn't clamp blend mix with blend hw 1 as we want alpha higher
 		float C_clamped = C;
 		if (PS_BLEND_MIX > 0 && PS_BLEND_HW != 1 && PS_BLEND_HW != 2)
-			C_clamped = min(C_clamped, 1.0f);
+			C_clamped = saturate(C_clamped);
 
 		if (PS_BLEND_A == PS_BLEND_B)
 			Color.rgb = D;
@@ -953,17 +953,13 @@ void ps_blend(inout float4 Color, inout float4 As_rgba, float2 pos_xy)
 		if (PS_BLEND_HW == 1)
 		{
 			// Needed for Cd * (As/Ad/F + 1) blending modes
-
 			Color.rgb = (float3)255.0f;
 		}
 		else if (PS_BLEND_HW == 2)
 		{
 			// Cd*As,Cd*Ad or Cd*F
-
 			float Alpha = PS_BLEND_C == 2 ? Af : As;
-
-			Color.rgb = saturate((float3)Alpha - (float3)1.0f);
-			Color.rgb *= (float3)255.0f;
+			Color.rgb = saturate((float3)Alpha - (float3)1.0f) * (float3)255.0f;
 		}
 		else if (PS_BLEND_HW == 3 && PS_RTA_CORRECTION == 0)
 		{

diff --git a/pcsx2/GS/Renderers/Metal/tfx.metal b/pcsx2/GS/Renderers/Metal/tfx.metal
@@ -967,7 +967,7 @@ struct PSMain
 			// We shouldn't clamp blend mix with blend hw 1 as we want alpha higher
 			float C_clamped = C;
 			if (PS_BLEND_MIX > 0 && PS_BLEND_HW != 1 && PS_BLEND_HW != 2)
-				C_clamped = min(C_clamped, 1.f);
+				C_clamped = saturate(C_clamped);
 
 			if (PS_BLEND_A == PS_BLEND_B)
 				Color.rgb = D;
@@ -1019,13 +1019,14 @@ struct PSMain
 		}
 		else
 		{
-			// Needed for Cd * (As/Ad/F + 1) blending mdoes
 			if (PS_BLEND_HW == 1)
 			{
+				// Needed for Cd * (As/Ad/F + 1) blending modes
 				Color.rgb = 255.f;
 			}
 			else if (PS_BLEND_HW == 2)
 			{
+				// Cd*As,Cd*Ad or Cd*F
 				float Alpha = PS_BLEND_C == 2 ? cb.alpha_fix : As;
 				Color.rgb = saturate(Alpha - 1.f) * 255.f;
 			}

diff --git a/pcsx2/ShaderCacheVersion.h b/pcsx2/ShaderCacheVersion.h
@@ -3,4 +3,4 @@
 
 /// Version number for GS and other shaders. Increment whenever any of the contents of the
 /// shaders change, to invalidate the cache.
-static constexpr u32 SHADER_CACHE_VERSION = 45;
+static constexpr u32 SHADER_CACHE_VERSION = 46;