From 271a9fe7a900634a1d9aeaf8f03218658fee246a Mon Sep 17 00:00:00 2001
From: Jules Blok <jules.blok@gmail.com>
Date: Fri, 13 Jan 2017 14:01:04 +0100
Subject: [PATCH] VertexShaderManager: Break up the conditions to make it
 readable.

---
 .../Core/VideoCommon/VertexShaderManager.cpp  | 51 ++++++++++---------
 1 file changed, 27 insertions(+), 24 deletions(-)

diff --git a/Source/Core/VideoCommon/VertexShaderManager.cpp b/Source/Core/VideoCommon/VertexShaderManager.cpp
index 32799d2f01..e516c2c63c 100644
--- a/Source/Core/VideoCommon/VertexShaderManager.cpp
+++ b/Source/Core/VideoCommon/VertexShaderManager.cpp
@@ -387,42 +387,45 @@ void VertexShaderManager::SetConstants()
     constants.pixelcentercorrection[0] = pixel_center_correction * pixel_size_x;
     constants.pixelcentercorrection[1] = pixel_center_correction * pixel_size_y;
 
-    if (g_ActiveConfig.backend_info.bSupportsDepthClamp &&
-        ((fabs(xfmem.viewport.zRange) > 16777215.0f || fabs(xfmem.viewport.farZ) > 16777215.0f) ||
-         (xfmem.viewport.zRange < 0.0f &&
-          !g_ActiveConfig.backend_info.bSupportsReversedDepthRange)))
+    // By default we don't change the depth value at all in the vertex shader.
+    constants.pixelcentercorrection[2] = 1.0f;
+    constants.pixelcentercorrection[3] = 0.0f;
+
+    if (g_ActiveConfig.backend_info.bSupportsDepthClamp)
     {
-      // The depth range is handled in the vertex shader. We need to reverse
+      // Oversized depth ranges are handled in the vertex shader. We need to reverse
       // the far value to get a reversed depth range mapping. This is necessary
       // because the standard depth range equation pushes all depth values towards
       // the back of the depth buffer where conventionally depth buffers have the
       // least precision.
       if (g_ActiveConfig.backend_info.bSupportsReversedDepthRange)
       {
-        // For backends that support reversing the depth range we also support cases
-        // where the console also uses reversed depth with the same accuracy. We need
-        // to make sure the depth range is positive here and then reverse the depth in
-        // the backend viewport.
-        constants.pixelcentercorrection[2] = fabs(xfmem.viewport.zRange) / 16777215.0f;
-        if (xfmem.viewport.zRange < 0.0f)
-          constants.pixelcentercorrection[3] = xfmem.viewport.farZ / 16777215.0f;
-        else
-          constants.pixelcentercorrection[3] = 1.0f - xfmem.viewport.farZ / 16777215.0f;
+        if (fabs(xfmem.viewport.zRange) > 16777215.0f || fabs(xfmem.viewport.farZ) > 16777215.0f)
+        {
+          // For backends that support reversing the depth range we also support cases
+          // where the console also uses reversed depth with the same accuracy. We need
+          // to make sure the depth range is positive here and then reverse the depth in
+          // the backend viewport.
+          constants.pixelcentercorrection[2] = fabs(xfmem.viewport.zRange) / 16777215.0f;
+          if (xfmem.viewport.zRange < 0.0f)
+            constants.pixelcentercorrection[3] = xfmem.viewport.farZ / 16777215.0f;
+          else
+            constants.pixelcentercorrection[3] = 1.0f - xfmem.viewport.farZ / 16777215.0f;
+        }
       }
       else
       {
-        // For backends that don't support reversing the depth range we can still render
-        // cases where the console uses reversed depth correctly. But we simply can't
-        // provide the same accuracy as the console.
-        constants.pixelcentercorrection[2] = xfmem.viewport.zRange / 16777215.0f;
-        constants.pixelcentercorrection[3] = 1.0f - xfmem.viewport.farZ / 16777215.0f;
+        if (xfmem.viewport.zRange < 0.0f || xfmem.viewport.zRange > 16777215.0f ||
+            fabs(xfmem.viewport.farZ) > 16777215.0f)
+        {
+          // For backends that don't support reversing the depth range we can still render
+          // cases where the console uses reversed depth correctly. But we simply can't
+          // provide the same accuracy as the console.
+          constants.pixelcentercorrection[2] = xfmem.viewport.zRange / 16777215.0f;
+          constants.pixelcentercorrection[3] = 1.0f - xfmem.viewport.farZ / 16777215.0f;
+        }
       }
     }
-    else
-    {
-      constants.pixelcentercorrection[2] = 1.0f;
-      constants.pixelcentercorrection[3] = 0.0f;
-    }
 
     dirty = true;
     // This is so implementation-dependent that we can't have it here.