Replace manual calculations with std::lerp and std::midpoint

5 files changed, 19 insertions, 8 deletions

diff --git a/Source/Core/VideoCommon/PerformanceTracker.cpp b/Source/Core/VideoCommon/PerformanceTracker.cpp
index 3d519865be..2ff6a7863b 100644
--- a/Source/Core/VideoCommon/PerformanceTracker.cpp
+++ b/Source/Core/VideoCommon/PerformanceTracker.cpp
@@ -94,7 +94,7 @@ void PerformanceTracker::HandleRawDt(DT diff)
   // Sometimes euler averages can break when the average is inf/nan
   const auto hz_avg = m_hz_avg.load();
   if (std::isfinite(hz_avg))
-    m_hz_avg = hz_avg + a * (hz - hz_avg);
+    m_hz_avg = std::lerp(hz_avg, hz, a);
   else
     m_hz_avg = hz;
 
diff --git a/Source/Core/VideoCommon/ShaderGenCommon.h b/Source/Core/VideoCommon/ShaderGenCommon.h
index 7d2c80f086..3ec230b35f 100644
--- a/Source/Core/VideoCommon/ShaderGenCommon.h
+++ b/Source/Core/VideoCommon/ShaderGenCommon.h
@@ -6,6 +6,7 @@
 #include <cstring>
 #include <functional>
 #include <iterator>
+#include <numeric>
 #include <string>
 #include <string_view>
 #include <type_traits>
@@ -247,7 +248,7 @@ void WriteSwitch(ShaderCode& out, APIType ApiType, std::string_view variable,
     }
     else
     {
-      u32 mid = low + ((high - low) / 2);
+      u32 mid = std::midpoint(low, high);
       out.Write("{:{}}if ({} < {}u) {{\n", "", cur_indent, variable, mid);
       BuildTree(cur_indent + 2, low, mid);
       out.Write("{:{}}}} else {{\n", "", cur_indent);
diff --git a/Source/Core/VideoCommon/TextureDecoder_Common.cpp b/Source/Core/VideoCommon/TextureDecoder_Common.cpp
index 3506514a54..a9e0cf91d8 100644
--- a/Source/Core/VideoCommon/TextureDecoder_Common.cpp
+++ b/Source/Core/VideoCommon/TextureDecoder_Common.cpp
@@ -4,6 +4,7 @@
 #include <algorithm>
 #include <array>
 #include <cstddef>
+#include <numeric>
 #include <span>
 
 #include "Common/CommonTypes.h"
@@ -602,12 +603,14 @@ void TexDecoder_DecodeTexel(u8* dst, std::span<const u8> src, int s, int t, int
       color = MakeRGBA(DXTBlend(red1, red2), DXTBlend(green1, green2), DXTBlend(blue1, blue2), 255);
       break;
     case 6:
-      color = MakeRGBA((red1 + red2) / 2, (green1 + green2) / 2, (blue1 + blue2) / 2, 255);
+      color = MakeRGBA(std::midpoint(red1, red2), std::midpoint(green1, green2),
+                       std::midpoint(blue1, blue2), 255);
       break;
     case 7:
       // color[3] is the same as color[2] (average of both colors), but transparent.
       // This differs from DXT1 where color[3] is transparent black.
-      color = MakeRGBA((red1 + red2) / 2, (green1 + green2) / 2, (blue1 + blue2) / 2, 0);
+      color = MakeRGBA(std::midpoint(red1, red2), std::midpoint(green1, green2),
+                       std::midpoint(blue1, blue2), 0);
       break;
     default:
       color = 0;
diff --git a/Source/Core/VideoCommon/TextureDecoder_Generic.cpp b/Source/Core/VideoCommon/TextureDecoder_Generic.cpp
index 835ddb523e..04dd0456b2 100644
--- a/Source/Core/VideoCommon/TextureDecoder_Generic.cpp
+++ b/Source/Core/VideoCommon/TextureDecoder_Generic.cpp
@@ -5,6 +5,7 @@
 
 #include <algorithm>
 #include <cmath>
+#include <numeric>
 
 #include "Common/CPUDetect.h"
 #include "Common/CommonTypes.h"
@@ -151,8 +152,10 @@ static void DecodeDXTBlock(u32* dst, const DXTBlock* src, int pitch)
   {
     // color[3] is the same as color[2] (average of both colors), but transparent.
     // This differs from DXT1 where color[3] is transparent black.
-    colors[2] = MakeRGBA((red1 + red2) / 2, (green1 + green2) / 2, (blue1 + blue2) / 2, 255);
-    colors[3] = MakeRGBA((red1 + red2) / 2, (green1 + green2) / 2, (blue1 + blue2) / 2, 0);
+    colors[2] = MakeRGBA(std::midpoint(red1, red2), std::midpoint(green1, green2),
+                         std::midpoint(blue1, blue2), 255);
+    colors[3] = MakeRGBA(std::midpoint(red1, red2), std::midpoint(green1, green2),
+                         std::midpoint(blue1, blue2), 0);
   }
 
   for (int y = 0; y < 4; y++)
diff --git a/Source/Core/VideoCommon/TextureDecoder_x64.cpp b/Source/Core/VideoCommon/TextureDecoder_x64.cpp
index 3918361561..a3bbcd8020 100644
--- a/Source/Core/VideoCommon/TextureDecoder_x64.cpp
+++ b/Source/Core/VideoCommon/TextureDecoder_x64.cpp
@@ -3,6 +3,8 @@
 
 #include "VideoCommon/TextureDecoder.h"
 
+#include <numeric>
+
 #ifdef CHECK
 #include "Common/Assert.h"
 #endif
@@ -188,8 +190,10 @@ static void DecodeDXTBlock(u32* dst, const DXTBlock* src, int pitch)
   {
     // color[3] is the same as color[2] (average of both colors), but transparent.
     // This differs from DXT1 where color[3] is transparent black.
-    colors[2] = MakeRGBA((red1 + red2) / 2, (green1 + green2) / 2, (blue1 + blue2) / 2, 255);
-    colors[3] = MakeRGBA((red1 + red2) / 2, (green1 + green2) / 2, (blue1 + blue2) / 2, 0);
+    colors[2] = MakeRGBA(std::midpoint(red1 + red2), std::midpoint(green1, green2),
+                         std::midpoint(blue1, blue2), 255);
+    colors[3] = MakeRGBA(std::midpoint(red1 + red2), std::midpoint(green1, green2),
+                         std::midpoint(blue1, blue2), 0);
   }
 
   for (int y = 0; y < 4; y++)