From 28e6e259edc6828b467346d8e3f532c01791eabc Mon Sep 17 00:00:00 2001
From: Jules Blok <jules.blok@gmail.com>
Date: Sun, 19 Feb 2017 16:41:04 +0100
Subject: [PATCH 1/5] VideoBackends: Set the maximum range when the depth range
 is oversized.

The depth values generated by the vertex shader need to be clamped correctly.
---
 Source/Core/VideoBackends/D3D/Render.cpp      |  8 ++++---
 Source/Core/VideoBackends/D3D12/Render.cpp    |  8 ++++---
 Source/Core/VideoBackends/OGL/Render.cpp      | 23 +++++++++++++++----
 Source/Core/VideoBackends/Vulkan/Renderer.cpp | 11 +++++----
 4 files changed, 36 insertions(+), 14 deletions(-)

diff --git a/Source/Core/VideoBackends/D3D/Render.cpp b/Source/Core/VideoBackends/D3D/Render.cpp
index bf1500ab0f..431690ca25 100644
--- a/Source/Core/VideoBackends/D3D/Render.cpp
+++ b/Source/Core/VideoBackends/D3D/Render.cpp
@@ -576,10 +576,12 @@ void Renderer::SetViewport()
     Ht = -Ht;
   }
 
-  // If an inverted depth range is used, which D3D doesn't support,
-  // we need to calculate the depth range in the vertex shader.
-  if (xfmem.viewport.zRange < 0.0f)
+  // If an inverted or oversized depth range is used, we need to calculate the depth range in the
+  // vertex shader.
+  if (xfmem.viewport.zRange < 0.0f || fabs(xfmem.viewport.zRange) > 16777215.0f ||
+      fabs(xfmem.viewport.farZ) > 16777215.0f)
   {
+    // We need to ensure depth values are clamped the maximum value supported by the console GPU.
     min_depth = 0.0f;
     max_depth = GX_MAX_DEPTH;
   }
diff --git a/Source/Core/VideoBackends/D3D12/Render.cpp b/Source/Core/VideoBackends/D3D12/Render.cpp
index 812a0adf11..d72ab7497a 100644
--- a/Source/Core/VideoBackends/D3D12/Render.cpp
+++ b/Source/Core/VideoBackends/D3D12/Render.cpp
@@ -481,10 +481,12 @@ void Renderer::SetViewport()
     height = -height;
   }
 
-  // If an inverted depth range is used, which D3D doesn't support,
-  // we need to calculate the depth range in the vertex shader.
-  if (xfmem.viewport.zRange < 0.0f)
+  // If an inverted or oversized depth range is used, we need to calculate the depth range in the
+  // vertex shader.
+  if (xfmem.viewport.zRange < 0.0f || fabs(xfmem.viewport.zRange) > 16777215.0f ||
+      fabs(xfmem.viewport.farZ) > 16777215.0f)
   {
+    // We need to ensure depth values are clamped the maximum value supported by the console GPU.
     min_depth = 0.0f;
     max_depth = GX_MAX_DEPTH;
   }
diff --git a/Source/Core/VideoBackends/OGL/Render.cpp b/Source/Core/VideoBackends/OGL/Render.cpp
index a92c4810f4..f55d06ecbc 100644
--- a/Source/Core/VideoBackends/OGL/Render.cpp
+++ b/Source/Core/VideoBackends/OGL/Render.cpp
@@ -1123,6 +1123,24 @@ void Renderer::SetViewport()
     Height *= -1;
   }
 
+  // If an oversized depth range is used, we need to calculate the depth range in the vertex shader.
+  if (g_ActiveConfig.backend_info.bSupportsDepthClamp &&
+      (fabs(xfmem.viewport.zRange) > 16777215.0f || fabs(xfmem.viewport.farZ) > 16777215.0f))
+  {
+    // We need to ensure depth values are clamped the maximum value supported by the console GPU.
+    // Taking into account whether the depth range is inverted or not.
+    if (xfmem.viewport.zRange < 0.0f)
+    {
+      min_depth = GX_MAX_DEPTH;
+      max_depth = 0.0f;
+    }
+    else
+    {
+      min_depth = 0.0f;
+      max_depth = GX_MAX_DEPTH;
+    }
+  }
+
   // Update the view port
   if (g_ogl_config.bSupportViewportFloat)
   {
@@ -1134,10 +1152,7 @@ void Renderer::SetViewport()
     glViewport(iceilf(X), iceilf(Y), iceilf(Width), iceilf(Height));
   }
 
-  // Set the reversed depth range. If we do depth clipping and depth range in the
-  // vertex shader we only need to ensure depth values don't exceed the maximum
-  // value supported by the console GPU. If not, we simply clamp the near/far values
-  // themselves to the maximum value as done above.
+  // Set the reversed depth range.
   glDepthRangef(max_depth, min_depth);
 }
 
diff --git a/Source/Core/VideoBackends/Vulkan/Renderer.cpp b/Source/Core/VideoBackends/Vulkan/Renderer.cpp
index 77f6fd3453..765601b329 100644
--- a/Source/Core/VideoBackends/Vulkan/Renderer.cpp
+++ b/Source/Core/VideoBackends/Vulkan/Renderer.cpp
@@ -4,6 +4,7 @@
 
 #include "VideoBackends/Vulkan/Renderer.h"
 
+#include <cmath>
 #include <cstddef>
 #include <cstdio>
 #include <limits>
@@ -1655,11 +1656,13 @@ void Renderer::SetViewport()
     height = -height;
   }
 
-  // If an inverted depth range is used, which the Vulkan drivers don't
-  // support, we need to calculate the depth range in the vertex shader.
-  // TODO: Make this into a DriverDetails bug and write a test for CTS.
-  if (xfmem.viewport.zRange < 0.0f)
+  // If an oversized or inverted depth range is used, we need to calculate the depth range in the
+  // vertex shader.
+  // TODO: Inverted depth ranges are bugged in all drivers, which should be added to DriverDetails.
+  if (xfmem.viewport.zRange < 0.0f || fabs(xfmem.viewport.zRange) > 16777215.0f ||
+      fabs(xfmem.viewport.farZ) > 16777215.0f)
   {
+    // We need to ensure depth values are clamped the maximum value supported by the console GPU.
     min_depth = 0.0f;
     max_depth = GX_MAX_DEPTH;
   }

From 94522d4cf3f18ba0783a877a8254537f0ff383ac Mon Sep 17 00:00:00 2001
From: Jules Blok <jules.blok@gmail.com>
Date: Sat, 6 Aug 2016 13:30:32 +0200
Subject: [PATCH 2/5] OGL: Add support for glDepthRangedNV to handle oversized
 depth ranges.

---
 Source/Core/Common/Common.vcxproj             |  1 +
 Source/Core/Common/Common.vcxproj.filters     |  3 +
 .../Common/GL/GLExtensions/GLExtensions.cpp   | 23 ++++---
 .../Common/GL/GLExtensions/GLExtensions.h     |  1 +
 .../GL/GLExtensions/NV_depth_buffer_float.h   | 41 ++++++++++++
 Source/Core/Core/Analytics.cpp                |  2 +
 Source/Core/VideoBackends/D3D/main.cpp        |  1 +
 Source/Core/VideoBackends/D3D12/main.cpp      |  1 +
 .../Core/VideoBackends/Null/NullBackend.cpp   |  1 +
 Source/Core/VideoBackends/OGL/Render.cpp      | 64 +++++++++++--------
 Source/Core/VideoBackends/OGL/main.cpp        |  1 +
 Source/Core/VideoBackends/Software/SWmain.cpp |  1 +
 .../VideoBackends/Vulkan/VulkanContext.cpp    | 19 +++---
 .../Core/VideoCommon/VertexShaderManager.cpp  |  3 +-
 Source/Core/VideoCommon/VideoConfig.h         |  1 +
 15 files changed, 119 insertions(+), 44 deletions(-)
 create mode 100644 Source/Core/Common/GL/GLExtensions/NV_depth_buffer_float.h

diff --git a/Source/Core/Common/Common.vcxproj b/Source/Core/Common/Common.vcxproj
index 831dcad4a7..b4a0f1fba5 100644
--- a/Source/Core/Common/Common.vcxproj
+++ b/Source/Core/Common/Common.vcxproj
@@ -105,6 +105,7 @@
     <ClInclude Include="GL\GLExtensions\gl_common.h" />
     <ClInclude Include="GL\GLExtensions\HP_occlusion_test.h" />
     <ClInclude Include="GL\GLExtensions\KHR_debug.h" />
+    <ClInclude Include="GL\GLExtensions\NV_depth_buffer_float.h" />
     <ClInclude Include="GL\GLExtensions\NV_occlusion_query_samples.h" />
     <ClInclude Include="GL\GLExtensions\NV_primitive_restart.h" />
     <ClInclude Include="GL\GLInterfaceBase.h" />
diff --git a/Source/Core/Common/Common.vcxproj.filters b/Source/Core/Common/Common.vcxproj.filters
index 3c9b952742..77d639045a 100644
--- a/Source/Core/Common/Common.vcxproj.filters
+++ b/Source/Core/Common/Common.vcxproj.filters
@@ -218,6 +218,9 @@
     <ClInclude Include="GL\GLExtensions\NV_primitive_restart.h">
       <Filter>GL\GLExtensions</Filter>
     </ClInclude>
+    <ClInclude Include="GL\GLExtensions\NV_depth_buffer_float.h">
+      <Filter>GL\GLExtensions</Filter>
+    </ClInclude>
     <ClInclude Include="GL\GLInterface\WGL.h">
       <Filter>GL\GLInterface</Filter>
     </ClInclude>
diff --git a/Source/Core/Common/GL/GLExtensions/GLExtensions.cpp b/Source/Core/Common/GL/GLExtensions/GLExtensions.cpp
index 591792468e..ff252bb1f7 100644
--- a/Source/Core/Common/GL/GLExtensions/GLExtensions.cpp
+++ b/Source/Core/Common/GL/GLExtensions/GLExtensions.cpp
@@ -984,6 +984,11 @@ PFNDOLCOPYIMAGESUBDATAPROC dolCopyImageSubData;
 // ARB_shader_storage_buffer_object
 PFNDOLSHADERSTORAGEBLOCKBINDINGPROC dolShaderStorageBlockBinding;
 
+// NV_depth_buffer_float
+PFNDOLDEPTHRANGEDNVPROC dolDepthRangedNV;
+PFNDOLCLEARDEPTHDNVPROC dolClearDepthdNV;
+PFNDOLDEPTHBOUNDSDNVPROC dolDepthBoundsdNV;
+
 // Creates a GLFunc object that requires a feature
 #define GLFUNC_REQUIRES(x, y)                                                                      \
   {                                                                                                \
@@ -1838,6 +1843,11 @@ const GLFunc gl_function_array[] = {
 
     // ARB_shader_storage_buffer_object
     GLFUNC_REQUIRES(glShaderStorageBlockBinding, "ARB_shader_storage_buffer_object !VERSION_4_3"),
+
+    // NV_depth_buffer_float
+    GLFUNC_REQUIRES(glDepthRangedNV, "GL_NV_depth_buffer_float"),
+    GLFUNC_REQUIRES(glClearDepthdNV, "GL_NV_depth_buffer_float"),
+    GLFUNC_REQUIRES(glDepthBoundsdNV, "GL_NV_depth_buffer_float"),
 };
 
 namespace GLExtensions
@@ -2060,26 +2070,21 @@ static void InitExtensionList()
       // Quite a lot of these had their names changed when merged in to core
       // Disable the ones that have
       std::string gl300exts[] = {
-          "GL_ARB_map_buffer_range",
+          "GL_ARB_map_buffer_range", "GL_ARB_color_buffer_float", "GL_ARB_texture_float",
+          "GL_ARB_half_float_pixel", "GL_ARB_framebuffer_object", "GL_ARB_texture_float",
+          "GL_ARB_vertex_array_object", "GL_NV_depth_buffer_float",
+          //"GL_EXT_texture_integer",
           //"GL_EXT_gpu_shader4",
           //"GL_APPLE_flush_buffer_range",
-          "GL_ARB_color_buffer_float",
-          //"GL_NV_depth_buffer_float",
-          "GL_ARB_texture_float",
           //"GL_EXT_packed_float",
           //"GL_EXT_texture_shared_exponent",
-          "GL_ARB_half_float_pixel",
           //"GL_NV_half_float",
-          "GL_ARB_framebuffer_object",
           //"GL_EXT_framebuffer_sRGB",
-          "GL_ARB_texture_float",
-          //"GL_EXT_texture_integer",
           //"GL_EXT_draw_buffers2",
           //"GL_EXT_texture_integer",
           //"GL_EXT_texture_array",
           //"GL_EXT_texture_compression_rgtc",
           //"GL_EXT_transform_feedback",
-          "GL_ARB_vertex_array_object",
           //"GL_NV_conditional_render",
           "VERSION_3_0",
       };
diff --git a/Source/Core/Common/GL/GLExtensions/GLExtensions.h b/Source/Core/Common/GL/GLExtensions/GLExtensions.h
index fa00aa4a97..4c58167700 100644
--- a/Source/Core/Common/GL/GLExtensions/GLExtensions.h
+++ b/Source/Core/Common/GL/GLExtensions/GLExtensions.h
@@ -31,6 +31,7 @@
 #include "Common/GL/GLExtensions/EXT_texture_filter_anisotropic.h"
 #include "Common/GL/GLExtensions/HP_occlusion_test.h"
 #include "Common/GL/GLExtensions/KHR_debug.h"
+#include "Common/GL/GLExtensions/NV_depth_buffer_float.h"
 #include "Common/GL/GLExtensions/NV_occlusion_query_samples.h"
 #include "Common/GL/GLExtensions/NV_primitive_restart.h"
 #include "Common/GL/GLExtensions/gl_1_1.h"
diff --git a/Source/Core/Common/GL/GLExtensions/NV_depth_buffer_float.h b/Source/Core/Common/GL/GLExtensions/NV_depth_buffer_float.h
new file mode 100644
index 0000000000..7912c55ba2
--- /dev/null
+++ b/Source/Core/Common/GL/GLExtensions/NV_depth_buffer_float.h
@@ -0,0 +1,41 @@
+/*
+** Copyright (c) 2013-2015 The Khronos Group Inc.
+**
+** Permission is hereby granted, free of charge, to any person obtaining a
+** copy of this software and/or associated documentation files (the
+** "Materials"), to deal in the Materials without restriction, including
+** without limitation the rights to use, copy, modify, merge, publish,
+** distribute, sublicense, and/or sell copies of the Materials, and to
+** permit persons to whom the Materials are furnished to do so, subject to
+** the following conditions:
+**
+** The above copyright notice and this permission notice shall be included
+** in all copies or substantial portions of the Materials.
+**
+** THE MATERIALS ARE PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+** EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+** MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
+** IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY
+** CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
+** TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
+** MATERIALS OR THE USE OR OTHER DEALINGS IN THE MATERIALS.
+*/
+
+#include "Common/GL/GLExtensions/gl_common.h"
+
+#define GL_DEPTH_COMPONENT32F_NV 0x8DAB
+#define GL_DEPTH32F_STENCIL8_NV 0x8DAC
+#define GL_FLOAT_32_UNSIGNED_INT_24_8_REV_NV 0x8DAD
+#define GL_DEPTH_BUFFER_FLOAT_MODE_NV 0x8DAF
+
+typedef void(APIENTRYP PFNDOLDEPTHRANGEDNVPROC)(GLdouble zNear, GLdouble zFar);
+typedef void(APIENTRYP PFNDOLCLEARDEPTHDNVPROC)(GLdouble depth);
+typedef void(APIENTRYP PFNDOLDEPTHBOUNDSDNVPROC)(GLdouble zmin, GLdouble zmax);
+
+extern PFNDOLDEPTHRANGEDNVPROC dolDepthRangedNV;
+extern PFNDOLCLEARDEPTHDNVPROC dolClearDepthdNV;
+extern PFNDOLDEPTHBOUNDSDNVPROC dolDepthBoundsdNV;
+
+#define glDepthRangedNV dolDepthRangedNV
+#define glClearDepthdNV dolClearDepthdNV
+#define glDepthBoundsdNV dolDepthBoundsdNV
diff --git a/Source/Core/Core/Analytics.cpp b/Source/Core/Core/Analytics.cpp
index 8638b79dba..7c71446565 100644
--- a/Source/Core/Core/Analytics.cpp
+++ b/Source/Core/Core/Analytics.cpp
@@ -234,6 +234,8 @@ void DolphinAnalytics::MakePerGameBuilder()
   builder.AddData("gpu-has-dual-source-blend", g_Config.backend_info.bSupportsDualSourceBlend);
   builder.AddData("gpu-has-primitive-restart", g_Config.backend_info.bSupportsPrimitiveRestart);
   builder.AddData("gpu-has-oversized-viewports", g_Config.backend_info.bSupportsOversizedViewports);
+  builder.AddData("gpu-has-oversized-depth-ranges",
+                  g_Config.backend_info.bSupportsOversizedDepthRanges);
   builder.AddData("gpu-has-geometry-shaders", g_Config.backend_info.bSupportsGeometryShaders);
   builder.AddData("gpu-has-3d-vision", g_Config.backend_info.bSupports3DVision);
   builder.AddData("gpu-has-early-z", g_Config.backend_info.bSupportsEarlyZ);
diff --git a/Source/Core/VideoBackends/D3D/main.cpp b/Source/Core/VideoBackends/D3D/main.cpp
index fe32d89603..4f2a32d32e 100644
--- a/Source/Core/VideoBackends/D3D/main.cpp
+++ b/Source/Core/VideoBackends/D3D/main.cpp
@@ -64,6 +64,7 @@ void VideoBackend::InitBackendInfo()
   g_Config.backend_info.bSupportsDualSourceBlend = true;
   g_Config.backend_info.bSupportsPrimitiveRestart = true;
   g_Config.backend_info.bSupportsOversizedViewports = false;
+  g_Config.backend_info.bSupportsOversizedDepthRanges = false;
   g_Config.backend_info.bSupportsGeometryShaders = true;
   g_Config.backend_info.bSupports3DVision = true;
   g_Config.backend_info.bSupportsPostProcessing = false;
diff --git a/Source/Core/VideoBackends/D3D12/main.cpp b/Source/Core/VideoBackends/D3D12/main.cpp
index ef377bab41..7d903bae63 100644
--- a/Source/Core/VideoBackends/D3D12/main.cpp
+++ b/Source/Core/VideoBackends/D3D12/main.cpp
@@ -68,6 +68,7 @@ void VideoBackend::InitBackendInfo()
   g_Config.backend_info.bSupportsDualSourceBlend = true;
   g_Config.backend_info.bSupportsPrimitiveRestart = true;
   g_Config.backend_info.bSupportsOversizedViewports = false;
+  g_Config.backend_info.bSupportsOversizedDepthRanges = false;
   g_Config.backend_info.bSupportsGeometryShaders = true;
   g_Config.backend_info.bSupports3DVision = true;
   g_Config.backend_info.bSupportsPostProcessing = false;
diff --git a/Source/Core/VideoBackends/Null/NullBackend.cpp b/Source/Core/VideoBackends/Null/NullBackend.cpp
index 1e3117088e..854b8450a4 100644
--- a/Source/Core/VideoBackends/Null/NullBackend.cpp
+++ b/Source/Core/VideoBackends/Null/NullBackend.cpp
@@ -28,6 +28,7 @@ void VideoBackend::InitBackendInfo()
   g_Config.backend_info.bSupportsDualSourceBlend = true;
   g_Config.backend_info.bSupportsPrimitiveRestart = true;
   g_Config.backend_info.bSupportsOversizedViewports = true;
+  g_Config.backend_info.bSupportsOversizedDepthRanges = false;
   g_Config.backend_info.bSupportsGeometryShaders = true;
   g_Config.backend_info.bSupports3DVision = false;
   g_Config.backend_info.bSupportsEarlyZ = true;
diff --git a/Source/Core/VideoBackends/OGL/Render.cpp b/Source/Core/VideoBackends/OGL/Render.cpp
index f55d06ecbc..abee545ba4 100644
--- a/Source/Core/VideoBackends/OGL/Render.cpp
+++ b/Source/Core/VideoBackends/OGL/Render.cpp
@@ -474,6 +474,8 @@ Renderer::Renderer()
 
   // Clip distance support is useless without a method to clamp the depth range
   g_Config.backend_info.bSupportsDepthClamp = GLExtensions::Supports("GL_ARB_depth_clamp");
+  g_Config.backend_info.bSupportsOversizedDepthRanges =
+      GLExtensions::Supports("GL_NV_depth_buffer_float");
 
   g_ogl_config.bSupportsGLSLCache = GLExtensions::Supports("GL_ARB_get_program_binary");
   g_ogl_config.bSupportsGLPinnedMemory = GLExtensions::Supports("GL_AMD_pinned_memory");
@@ -666,7 +668,7 @@ Renderer::Renderer()
                                    g_ogl_config.gl_renderer, g_ogl_config.gl_version),
                   5000);
 
-  WARN_LOG(VIDEO, "Missing OGL Extensions: %s%s%s%s%s%s%s%s%s%s%s%s%s%s",
+  WARN_LOG(VIDEO, "Missing OGL Extensions: %s%s%s%s%s%s%s%s%s%s%s%s%s%s%s",
            g_ActiveConfig.backend_info.bSupportsDualSourceBlend ? "" : "DualSourceBlend ",
            g_ActiveConfig.backend_info.bSupportsPrimitiveRestart ? "" : "PrimitiveRestart ",
            g_ActiveConfig.backend_info.bSupportsEarlyZ ? "" : "EarlyZ ",
@@ -679,7 +681,8 @@ Renderer::Renderer()
            g_ActiveConfig.backend_info.bSupportsGSInstancing ? "" : "GSInstancing ",
            g_ActiveConfig.backend_info.bSupportsClipControl ? "" : "ClipControl ",
            g_ogl_config.bSupportsCopySubImage ? "" : "CopyImageSubData ",
-           g_ActiveConfig.backend_info.bSupportsDepthClamp ? "" : "DepthClamp ");
+           g_ActiveConfig.backend_info.bSupportsDepthClamp ? "" : "DepthClamp ",
+           g_ActiveConfig.backend_info.bSupportsOversizedDepthRanges ? "" : "DepthRangedNV ");
 
   s_last_multisamples = g_ActiveConfig.iMultisamples;
   s_MSAASamples = s_last_multisamples;
@@ -1108,10 +1111,6 @@ void Renderer::SetViewport()
                           (float)scissorYOff);
   float Width = EFBToScaledXf(2.0f * xfmem.viewport.wd);
   float Height = EFBToScaledYf(-2.0f * xfmem.viewport.ht);
-  float range = MathUtil::Clamp<float>(xfmem.viewport.zRange, -16777215.0f, 16777215.0f);
-  float min_depth =
-      MathUtil::Clamp<float>(xfmem.viewport.farZ - range, 0.0f, 16777215.0f) / 16777216.0f;
-  float max_depth = MathUtil::Clamp<float>(xfmem.viewport.farZ, 0.0f, 16777215.0f) / 16777216.0f;
   if (Width < 0)
   {
     X += Width;
@@ -1123,24 +1122,6 @@ void Renderer::SetViewport()
     Height *= -1;
   }
 
-  // If an oversized depth range is used, we need to calculate the depth range in the vertex shader.
-  if (g_ActiveConfig.backend_info.bSupportsDepthClamp &&
-      (fabs(xfmem.viewport.zRange) > 16777215.0f || fabs(xfmem.viewport.farZ) > 16777215.0f))
-  {
-    // We need to ensure depth values are clamped the maximum value supported by the console GPU.
-    // Taking into account whether the depth range is inverted or not.
-    if (xfmem.viewport.zRange < 0.0f)
-    {
-      min_depth = GX_MAX_DEPTH;
-      max_depth = 0.0f;
-    }
-    else
-    {
-      min_depth = 0.0f;
-      max_depth = GX_MAX_DEPTH;
-    }
-  }
-
   // Update the view port
   if (g_ogl_config.bSupportViewportFloat)
   {
@@ -1153,7 +1134,40 @@ void Renderer::SetViewport()
   }
 
   // Set the reversed depth range.
-  glDepthRangef(max_depth, min_depth);
+  if (g_ActiveConfig.backend_info.bSupportsOversizedDepthRanges)
+  {
+    float min_depth = (xfmem.viewport.farZ - xfmem.viewport.zRange) / 16777216.0f;
+    float max_depth = xfmem.viewport.farZ / 16777216.0f;
+    glDepthRangedNV(max_depth, min_depth);
+  }
+  else
+  {
+    float range = MathUtil::Clamp<float>(xfmem.viewport.zRange, -16777216.0f, 16777216.0f);
+    float min_depth =
+        MathUtil::Clamp<float>(xfmem.viewport.farZ - range, 0.0f, 16777215.0f) / 16777216.0f;
+    float max_depth = MathUtil::Clamp<float>(xfmem.viewport.farZ, 0.0f, 16777215.0f) / 16777216.0f;
+
+    // If an oversized depth range is used, we need to calculate the depth range in the
+    // vertex shader.
+    if (g_ActiveConfig.backend_info.bSupportsDepthClamp &&
+        (fabs(xfmem.viewport.zRange) > 16777215.0f || fabs(xfmem.viewport.farZ) > 16777215.0f))
+    {
+      // We need to ensure depth values are clamped the maximum value supported by the console GPU.
+      // Taking into account whether the depth range is inverted or not.
+      if (xfmem.viewport.zRange < 0.0f)
+      {
+        min_depth = GX_MAX_DEPTH;
+        max_depth = 0.0f;
+      }
+      else
+      {
+        min_depth = 0.0f;
+        max_depth = GX_MAX_DEPTH;
+      }
+    }
+
+    glDepthRangef(max_depth, min_depth);
+  }
 }
 
 void Renderer::ClearScreen(const EFBRectangle& rc, bool colorEnable, bool alphaEnable, bool zEnable,
diff --git a/Source/Core/VideoBackends/OGL/main.cpp b/Source/Core/VideoBackends/OGL/main.cpp
index 0d46982cca..fa08587ca1 100644
--- a/Source/Core/VideoBackends/OGL/main.cpp
+++ b/Source/Core/VideoBackends/OGL/main.cpp
@@ -107,6 +107,7 @@ void VideoBackend::InitBackendInfo()
   g_Config.backend_info.bSupportsInternalResolutionFrameDumps = true;
 
   // Overwritten in Render.cpp later
+  g_Config.backend_info.bSupportsOversizedDepthRanges = false;
   g_Config.backend_info.bSupportsDualSourceBlend = true;
   g_Config.backend_info.bSupportsPrimitiveRestart = true;
   g_Config.backend_info.bSupportsPaletteConversion = true;
diff --git a/Source/Core/VideoBackends/Software/SWmain.cpp b/Source/Core/VideoBackends/Software/SWmain.cpp
index adbe5046b6..e840ac4921 100644
--- a/Source/Core/VideoBackends/Software/SWmain.cpp
+++ b/Source/Core/VideoBackends/Software/SWmain.cpp
@@ -128,6 +128,7 @@ void VideoSoftware::InitBackendInfo()
   g_Config.backend_info.bSupportsDualSourceBlend = true;
   g_Config.backend_info.bSupportsEarlyZ = true;
   g_Config.backend_info.bSupportsOversizedViewports = true;
+  g_Config.backend_info.bSupportsOversizedDepthRanges = true;
   g_Config.backend_info.bSupportsPrimitiveRestart = false;
   g_Config.backend_info.bSupportsMultithreading = false;
   g_Config.backend_info.bSupportsInternalResolutionFrameDumps = false;
diff --git a/Source/Core/VideoBackends/Vulkan/VulkanContext.cpp b/Source/Core/VideoBackends/Vulkan/VulkanContext.cpp
index 7dc809e6b2..d3f981e5f5 100644
--- a/Source/Core/VideoBackends/Vulkan/VulkanContext.cpp
+++ b/Source/Core/VideoBackends/Vulkan/VulkanContext.cpp
@@ -225,15 +225,16 @@ VulkanContext::GPUList VulkanContext::EnumerateGPUs(VkInstance instance)
 void VulkanContext::PopulateBackendInfo(VideoConfig* config)
 {
   config->backend_info.api_type = APIType::Vulkan;
-  config->backend_info.bSupportsExclusiveFullscreen = false;  // Currently WSI does not allow this.
-  config->backend_info.bSupports3DVision = false;             // D3D-exclusive.
-  config->backend_info.bSupportsOversizedViewports = true;    // Assumed support.
-  config->backend_info.bSupportsEarlyZ = true;                // Assumed support.
-  config->backend_info.bSupportsPrimitiveRestart = true;      // Assumed support.
-  config->backend_info.bSupportsBindingLayout = false;        // Assumed support.
-  config->backend_info.bSupportsPaletteConversion = true;     // Assumed support.
-  config->backend_info.bSupportsClipControl = true;           // Assumed support.
-  config->backend_info.bSupportsMultithreading = true;        // Assumed support.
+  config->backend_info.bSupportsExclusiveFullscreen = false;   // Currently WSI does not allow this.
+  config->backend_info.bSupports3DVision = false;              // D3D-exclusive.
+  config->backend_info.bSupportsOversizedViewports = true;     // Assumed support.
+  config->backend_info.bSupportsOversizedDepthRanges = false;  // No support yet.
+  config->backend_info.bSupportsEarlyZ = true;                 // Assumed support.
+  config->backend_info.bSupportsPrimitiveRestart = true;       // Assumed support.
+  config->backend_info.bSupportsBindingLayout = false;         // Assumed support.
+  config->backend_info.bSupportsPaletteConversion = true;      // Assumed support.
+  config->backend_info.bSupportsClipControl = true;            // Assumed support.
+  config->backend_info.bSupportsMultithreading = true;         // Assumed support.
   config->backend_info.bSupportsInternalResolutionFrameDumps = true;  // Assumed support.
   config->backend_info.bSupportsPostProcessing = false;               // No support yet.
   config->backend_info.bSupportsDualSourceBlend = false;              // Dependent on features.
diff --git a/Source/Core/VideoCommon/VertexShaderManager.cpp b/Source/Core/VideoCommon/VertexShaderManager.cpp
index e516c2c63c..ed8d52efb7 100644
--- a/Source/Core/VideoCommon/VertexShaderManager.cpp
+++ b/Source/Core/VideoCommon/VertexShaderManager.cpp
@@ -391,7 +391,8 @@ void VertexShaderManager::SetConstants()
     constants.pixelcentercorrection[2] = 1.0f;
     constants.pixelcentercorrection[3] = 0.0f;
 
-    if (g_ActiveConfig.backend_info.bSupportsDepthClamp)
+    if (g_ActiveConfig.backend_info.bSupportsDepthClamp &&
+        !g_ActiveConfig.backend_info.bSupportsOversizedDepthRanges)
     {
       // 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
diff --git a/Source/Core/VideoCommon/VideoConfig.h b/Source/Core/VideoCommon/VideoConfig.h
index 9e6b0180f3..2972dca664 100644
--- a/Source/Core/VideoCommon/VideoConfig.h
+++ b/Source/Core/VideoCommon/VideoConfig.h
@@ -172,6 +172,7 @@ struct VideoConfig final
     bool bSupportsDualSourceBlend;
     bool bSupportsPrimitiveRestart;
     bool bSupportsOversizedViewports;
+    bool bSupportsOversizedDepthRanges;
     bool bSupportsGeometryShaders;
     bool bSupports3DVision;
     bool bSupportsEarlyZ;         // needed by PixelShaderGen, so must stay in VideoCommon

From bde81269130c31c93cbb0f0f3ac8f23560751cac Mon Sep 17 00:00:00 2001
From: Jules Blok <jules.blok@gmail.com>
Date: Tue, 21 Feb 2017 16:15:22 +0100
Subject: [PATCH 3/5] VideoBackends: Remove depth range clamping hacks.

Oversized depth ranges are handled correctly now, we don't need to hack around them with clamps anymore.
---
 Source/Core/VideoBackends/D3D/Render.cpp      |  6 ++----
 Source/Core/VideoBackends/D3D12/Render.cpp    |  6 ++----
 Source/Core/VideoBackends/OGL/Render.cpp      | 16 +++++++++-------
 Source/Core/VideoBackends/Vulkan/Renderer.cpp |  6 ++----
 4 files changed, 15 insertions(+), 19 deletions(-)

diff --git a/Source/Core/VideoBackends/D3D/Render.cpp b/Source/Core/VideoBackends/D3D/Render.cpp
index 431690ca25..a100fb5616 100644
--- a/Source/Core/VideoBackends/D3D/Render.cpp
+++ b/Source/Core/VideoBackends/D3D/Render.cpp
@@ -561,10 +561,8 @@ void Renderer::SetViewport()
   float Y = Renderer::EFBToScaledYf(xfmem.viewport.yOrig + xfmem.viewport.ht - scissorYOff);
   float Wd = Renderer::EFBToScaledXf(2.0f * xfmem.viewport.wd);
   float Ht = Renderer::EFBToScaledYf(-2.0f * xfmem.viewport.ht);
-  float range = MathUtil::Clamp<float>(xfmem.viewport.zRange, 0.0f, 16777215.0f);
-  float min_depth =
-      MathUtil::Clamp<float>(xfmem.viewport.farZ - range, 0.0f, 16777215.0f) / 16777216.0f;
-  float max_depth = MathUtil::Clamp<float>(xfmem.viewport.farZ, 0.0f, 16777215.0f) / 16777216.0f;
+  float min_depth = (xfmem.viewport.farZ - xfmem.viewport.zRange) / 16777216.0f;
+  float max_depth = xfmem.viewport.farZ / 16777216.0f;
   if (Wd < 0.0f)
   {
     X += Wd;
diff --git a/Source/Core/VideoBackends/D3D12/Render.cpp b/Source/Core/VideoBackends/D3D12/Render.cpp
index d72ab7497a..d5bdaeb07a 100644
--- a/Source/Core/VideoBackends/D3D12/Render.cpp
+++ b/Source/Core/VideoBackends/D3D12/Render.cpp
@@ -466,10 +466,8 @@ void Renderer::SetViewport()
   float y = Renderer::EFBToScaledYf(xfmem.viewport.yOrig + xfmem.viewport.ht - scissor_y_offset);
   float width = Renderer::EFBToScaledXf(2.0f * xfmem.viewport.wd);
   float height = Renderer::EFBToScaledYf(-2.0f * xfmem.viewport.ht);
-  float range = MathUtil::Clamp<float>(xfmem.viewport.zRange, 0.0f, 16777215.0f);
-  float min_depth =
-      MathUtil::Clamp<float>(xfmem.viewport.farZ - range, 0.0f, 16777215.0f) / 16777216.0f;
-  float max_depth = MathUtil::Clamp<float>(xfmem.viewport.farZ, 0.0f, 16777215.0f) / 16777216.0f;
+  float min_depth = (xfmem.viewport.farZ - xfmem.viewport.zRange) / 16777216.0f;
+  float max_depth = xfmem.viewport.farZ / 16777216.0f;
   if (width < 0.0f)
   {
     x += width;
diff --git a/Source/Core/VideoBackends/OGL/Render.cpp b/Source/Core/VideoBackends/OGL/Render.cpp
index abee545ba4..f8405250d7 100644
--- a/Source/Core/VideoBackends/OGL/Render.cpp
+++ b/Source/Core/VideoBackends/OGL/Render.cpp
@@ -1111,6 +1111,8 @@ void Renderer::SetViewport()
                           (float)scissorYOff);
   float Width = EFBToScaledXf(2.0f * xfmem.viewport.wd);
   float Height = EFBToScaledYf(-2.0f * xfmem.viewport.ht);
+  float min_depth = (xfmem.viewport.farZ - xfmem.viewport.zRange) / 16777216.0f;
+  float max_depth = xfmem.viewport.farZ / 16777216.0f;
   if (Width < 0)
   {
     X += Width;
@@ -1136,17 +1138,10 @@ void Renderer::SetViewport()
   // Set the reversed depth range.
   if (g_ActiveConfig.backend_info.bSupportsOversizedDepthRanges)
   {
-    float min_depth = (xfmem.viewport.farZ - xfmem.viewport.zRange) / 16777216.0f;
-    float max_depth = xfmem.viewport.farZ / 16777216.0f;
     glDepthRangedNV(max_depth, min_depth);
   }
   else
   {
-    float range = MathUtil::Clamp<float>(xfmem.viewport.zRange, -16777216.0f, 16777216.0f);
-    float min_depth =
-        MathUtil::Clamp<float>(xfmem.viewport.farZ - range, 0.0f, 16777215.0f) / 16777216.0f;
-    float max_depth = MathUtil::Clamp<float>(xfmem.viewport.farZ, 0.0f, 16777215.0f) / 16777216.0f;
-
     // If an oversized depth range is used, we need to calculate the depth range in the
     // vertex shader.
     if (g_ActiveConfig.backend_info.bSupportsDepthClamp &&
@@ -1165,6 +1160,13 @@ void Renderer::SetViewport()
         max_depth = GX_MAX_DEPTH;
       }
     }
+    else
+    {
+      // There's no way to support oversized depth ranges in this situation. Let's just clamp the
+      // range to the maximum value supported by the console GPU and hope for the best.
+      min_depth = MathUtil::Clamp(min_depth, 0.0f, GX_MAX_DEPTH);
+      max_depth = MathUtil::Clamp(max_depth, 0.0f, GX_MAX_DEPTH);
+    }
 
     glDepthRangef(max_depth, min_depth);
   }
diff --git a/Source/Core/VideoBackends/Vulkan/Renderer.cpp b/Source/Core/VideoBackends/Vulkan/Renderer.cpp
index 765601b329..ebfc755327 100644
--- a/Source/Core/VideoBackends/Vulkan/Renderer.cpp
+++ b/Source/Core/VideoBackends/Vulkan/Renderer.cpp
@@ -1641,10 +1641,8 @@ void Renderer::SetViewport()
   float y = Renderer::EFBToScaledYf(xfmem.viewport.yOrig + xfmem.viewport.ht - scissor_y_offset);
   float width = Renderer::EFBToScaledXf(2.0f * xfmem.viewport.wd);
   float height = Renderer::EFBToScaledYf(-2.0f * xfmem.viewport.ht);
-  float range = MathUtil::Clamp<float>(xfmem.viewport.zRange, -16777215.0f, 16777215.0f);
-  float min_depth =
-      MathUtil::Clamp<float>(xfmem.viewport.farZ - range, 0.0f, 16777215.0f) / 16777216.0f;
-  float max_depth = MathUtil::Clamp<float>(xfmem.viewport.farZ, 0.0f, 16777215.0f) / 16777216.0f;
+  float min_depth = (xfmem.viewport.farZ - xfmem.viewport.zRange) / 16777216.0f;
+  float max_depth = xfmem.viewport.farZ / 16777216.0f;
   if (width < 0.0f)
   {
     x += width;

From a15555fe0304e1ba560f91f8bacc8b121d226d1c Mon Sep 17 00:00:00 2001
From: Jules Blok <jules.blok@gmail.com>
Date: Fri, 24 Feb 2017 15:16:28 +0100
Subject: [PATCH 4/5] VideoBackends: Use vertex shader depth range if ztexture
 is used.

---
 Source/Core/VideoBackends/D3D/Render.cpp      |  3 +-
 Source/Core/VideoBackends/D3D12/Render.cpp    |  3 +-
 Source/Core/VideoBackends/OGL/Render.cpp      | 47 +++++++++----------
 Source/Core/VideoBackends/Vulkan/Renderer.cpp |  4 +-
 Source/Core/VideoCommon/BPStructs.cpp         |  2 +
 Source/Core/VideoCommon/RenderBase.cpp        | 27 +++++++++++
 Source/Core/VideoCommon/RenderBase.h          |  2 +
 .../Core/VideoCommon/VertexShaderManager.cpp  | 41 ++++++----------
 8 files changed, 69 insertions(+), 60 deletions(-)

diff --git a/Source/Core/VideoBackends/D3D/Render.cpp b/Source/Core/VideoBackends/D3D/Render.cpp
index a100fb5616..15273ed719 100644
--- a/Source/Core/VideoBackends/D3D/Render.cpp
+++ b/Source/Core/VideoBackends/D3D/Render.cpp
@@ -576,8 +576,7 @@ void Renderer::SetViewport()
 
   // If an inverted or oversized depth range is used, we need to calculate the depth range in the
   // vertex shader.
-  if (xfmem.viewport.zRange < 0.0f || fabs(xfmem.viewport.zRange) > 16777215.0f ||
-      fabs(xfmem.viewport.farZ) > 16777215.0f)
+  if (UseVertexDepthRange())
   {
     // We need to ensure depth values are clamped the maximum value supported by the console GPU.
     min_depth = 0.0f;
diff --git a/Source/Core/VideoBackends/D3D12/Render.cpp b/Source/Core/VideoBackends/D3D12/Render.cpp
index d5bdaeb07a..4d2badc2e2 100644
--- a/Source/Core/VideoBackends/D3D12/Render.cpp
+++ b/Source/Core/VideoBackends/D3D12/Render.cpp
@@ -481,8 +481,7 @@ void Renderer::SetViewport()
 
   // If an inverted or oversized depth range is used, we need to calculate the depth range in the
   // vertex shader.
-  if (xfmem.viewport.zRange < 0.0f || fabs(xfmem.viewport.zRange) > 16777215.0f ||
-      fabs(xfmem.viewport.farZ) > 16777215.0f)
+  if (UseVertexDepthRange())
   {
     // We need to ensure depth values are clamped the maximum value supported by the console GPU.
     min_depth = 0.0f;
diff --git a/Source/Core/VideoBackends/OGL/Render.cpp b/Source/Core/VideoBackends/OGL/Render.cpp
index f8405250d7..ee7d37bb67 100644
--- a/Source/Core/VideoBackends/OGL/Render.cpp
+++ b/Source/Core/VideoBackends/OGL/Render.cpp
@@ -1135,41 +1135,36 @@ void Renderer::SetViewport()
     glViewport(iceilf(X), iceilf(Y), iceilf(Width), iceilf(Height));
   }
 
-  // Set the reversed depth range.
-  if (g_ActiveConfig.backend_info.bSupportsOversizedDepthRanges)
+  if (!g_ActiveConfig.backend_info.bSupportsOversizedDepthRanges &&
+      !g_ActiveConfig.backend_info.bSupportsDepthClamp)
   {
-    glDepthRangedNV(max_depth, min_depth);
+    // There's no way to support oversized depth ranges in this situation. Let's just clamp the
+    // range to the maximum value supported by the console GPU and hope for the best.
+    min_depth = MathUtil::Clamp(min_depth, 0.0f, GX_MAX_DEPTH);
+    max_depth = MathUtil::Clamp(max_depth, 0.0f, GX_MAX_DEPTH);
   }
-  else
+
+  if (UseVertexDepthRange())
   {
-    // If an oversized depth range is used, we need to calculate the depth range in the
-    // vertex shader.
-    if (g_ActiveConfig.backend_info.bSupportsDepthClamp &&
-        (fabs(xfmem.viewport.zRange) > 16777215.0f || fabs(xfmem.viewport.farZ) > 16777215.0f))
+    // We need to ensure depth values are clamped the maximum value supported by the console GPU.
+    // Taking into account whether the depth range is inverted or not.
+    if (xfmem.viewport.zRange < 0.0f)
     {
-      // We need to ensure depth values are clamped the maximum value supported by the console GPU.
-      // Taking into account whether the depth range is inverted or not.
-      if (xfmem.viewport.zRange < 0.0f)
-      {
-        min_depth = GX_MAX_DEPTH;
-        max_depth = 0.0f;
-      }
-      else
-      {
-        min_depth = 0.0f;
-        max_depth = GX_MAX_DEPTH;
-      }
+      min_depth = GX_MAX_DEPTH;
+      max_depth = 0.0f;
     }
     else
     {
-      // There's no way to support oversized depth ranges in this situation. Let's just clamp the
-      // range to the maximum value supported by the console GPU and hope for the best.
-      min_depth = MathUtil::Clamp(min_depth, 0.0f, GX_MAX_DEPTH);
-      max_depth = MathUtil::Clamp(max_depth, 0.0f, GX_MAX_DEPTH);
+      min_depth = 0.0f;
+      max_depth = GX_MAX_DEPTH;
     }
-
-    glDepthRangef(max_depth, min_depth);
   }
+
+  // Set the reversed depth range.
+  if (g_ActiveConfig.backend_info.bSupportsOversizedDepthRanges)
+    glDepthRangedNV(max_depth, min_depth);
+  else
+    glDepthRangef(max_depth, min_depth);
 }
 
 void Renderer::ClearScreen(const EFBRectangle& rc, bool colorEnable, bool alphaEnable, bool zEnable,
diff --git a/Source/Core/VideoBackends/Vulkan/Renderer.cpp b/Source/Core/VideoBackends/Vulkan/Renderer.cpp
index ebfc755327..3cf8919042 100644
--- a/Source/Core/VideoBackends/Vulkan/Renderer.cpp
+++ b/Source/Core/VideoBackends/Vulkan/Renderer.cpp
@@ -4,7 +4,6 @@
 
 #include "VideoBackends/Vulkan/Renderer.h"
 
-#include <cmath>
 #include <cstddef>
 #include <cstdio>
 #include <limits>
@@ -1657,8 +1656,7 @@ void Renderer::SetViewport()
   // If an oversized or inverted depth range is used, we need to calculate the depth range in the
   // vertex shader.
   // TODO: Inverted depth ranges are bugged in all drivers, which should be added to DriverDetails.
-  if (xfmem.viewport.zRange < 0.0f || fabs(xfmem.viewport.zRange) > 16777215.0f ||
-      fabs(xfmem.viewport.farZ) > 16777215.0f)
+  if (UseVertexDepthRange())
   {
     // We need to ensure depth values are clamped the maximum value supported by the console GPU.
     min_depth = 0.0f;
diff --git a/Source/Core/VideoCommon/BPStructs.cpp b/Source/Core/VideoCommon/BPStructs.cpp
index 128969af52..e42f36f471 100644
--- a/Source/Core/VideoCommon/BPStructs.cpp
+++ b/Source/Core/VideoCommon/BPStructs.cpp
@@ -332,6 +332,8 @@ static void BPWritten(const BPCmd& bp)
   {
     if (bp.changes & 3)
       PixelShaderManager::SetZTextureTypeChanged();
+    if (bp.changes & 12)
+      VertexShaderManager::SetViewportChanged();
 #if defined(_DEBUG) || defined(DEBUGFAST)
     const char* pzop[] = {"DISABLE", "ADD", "REPLACE", "?"};
     const char* pztype[] = {"Z8", "Z16", "Z24", "?"};
diff --git a/Source/Core/VideoCommon/RenderBase.cpp b/Source/Core/VideoCommon/RenderBase.cpp
index f47288ea4e..19ec2abed2 100644
--- a/Source/Core/VideoCommon/RenderBase.cpp
+++ b/Source/Core/VideoCommon/RenderBase.cpp
@@ -940,3 +940,30 @@ void Renderer::DumpFrameToImage(const FrameDumpConfig& config)
   TextureToPng(config.data, config.stride, filename, config.width, config.height, false);
   m_frame_dump_image_counter++;
 }
+
+bool Renderer::UseVertexDepthRange() const
+{
+  // We can't compute the depth range in the vertex shader if we don't support depth clamp.
+  if (!g_ActiveConfig.backend_info.bSupportsDepthClamp)
+    return false;
+
+  if (g_ActiveConfig.backend_info.bSupportsOversizedDepthRanges)
+  {
+    // We support oversized depth ranges, but we need a full depth range if a ztexture is used.
+    return bpmem.ztex2.type != ZTEXTURE_DISABLE;
+  }
+  else
+  {
+    // We need a full depth range if a ztexture is used.
+    if (bpmem.ztex2.type != ZTEXTURE_DISABLE)
+      return true;
+
+    // If an inverted depth range is unsupported, we also need to check if the range is inverted.
+    if (!g_ActiveConfig.backend_info.bSupportsReversedDepthRange && xfmem.viewport.zRange < 0.0f)
+      return true;
+
+    // If an oversized depth range or a ztexture is used, we need to calculate the depth range
+    // in the vertex shader.
+    return fabs(xfmem.viewport.zRange) > 16777215.0f || fabs(xfmem.viewport.farZ) > 16777215.0f;
+  }
+}
diff --git a/Source/Core/VideoCommon/RenderBase.h b/Source/Core/VideoCommon/RenderBase.h
index 46c01afb78..2be470fe38 100644
--- a/Source/Core/VideoCommon/RenderBase.h
+++ b/Source/Core/VideoCommon/RenderBase.h
@@ -145,6 +145,8 @@ public:
   // Final surface changing
   // This is called when the surface is resized (WX) or the window changes (Android).
   virtual void ChangeSurface(void* new_surface_handle) {}
+  bool UseVertexDepthRange() const;
+
 protected:
   static void CalculateTargetScale(int x, int y, int* scaledX, int* scaledY);
   bool CalculateTargetSize();
diff --git a/Source/Core/VideoCommon/VertexShaderManager.cpp b/Source/Core/VideoCommon/VertexShaderManager.cpp
index ed8d52efb7..5998fa2112 100644
--- a/Source/Core/VideoCommon/VertexShaderManager.cpp
+++ b/Source/Core/VideoCommon/VertexShaderManager.cpp
@@ -391,40 +391,27 @@ void VertexShaderManager::SetConstants()
     constants.pixelcentercorrection[2] = 1.0f;
     constants.pixelcentercorrection[3] = 0.0f;
 
-    if (g_ActiveConfig.backend_info.bSupportsDepthClamp &&
-        !g_ActiveConfig.backend_info.bSupportsOversizedDepthRanges)
+    if (g_renderer->UseVertexDepthRange())
     {
       // 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.
+      // the far value to use the reversed-Z trick.
       if (g_ActiveConfig.backend_info.bSupportsReversedDepthRange)
       {
-        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;
-        }
+        // Sometimes the console also tries to use the reversed-Z trick. We can only do
+        // that with the expected accuracy if the backend can reverse the depth range.
+        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
       {
-        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;
-        }
+        // For backends that don't support reversing the depth range we can still render
+        // cases where the console uses the reversed-Z trick. But we simply can't provide
+        // the expected accuracy, which might result in z-fighting.
+        constants.pixelcentercorrection[2] = xfmem.viewport.zRange / 16777215.0f;
+        constants.pixelcentercorrection[3] = 1.0f - xfmem.viewport.farZ / 16777215.0f;
       }
     }
 

From 3f41e6d4cf9f1a318c6d32fea4d2b422684961a3 Mon Sep 17 00:00:00 2001
From: Jules Blok <jules.blok@gmail.com>
Date: Fri, 10 Mar 2017 15:43:32 +0100
Subject: [PATCH 5/5] RenderBase: Check if early ztest is enabled before
 falling back to vertex depth range.

---
 Source/Core/VideoCommon/RenderBase.cpp | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/Source/Core/VideoCommon/RenderBase.cpp b/Source/Core/VideoCommon/RenderBase.cpp
index 19ec2abed2..8ee4de1546 100644
--- a/Source/Core/VideoCommon/RenderBase.cpp
+++ b/Source/Core/VideoCommon/RenderBase.cpp
@@ -947,15 +947,17 @@ bool Renderer::UseVertexDepthRange() const
   if (!g_ActiveConfig.backend_info.bSupportsDepthClamp)
     return false;
 
+  const bool ztexture_enabled = bpmem.ztex2.type != ZTEXTURE_DISABLE && !bpmem.zcontrol.early_ztest;
+
   if (g_ActiveConfig.backend_info.bSupportsOversizedDepthRanges)
   {
     // We support oversized depth ranges, but we need a full depth range if a ztexture is used.
-    return bpmem.ztex2.type != ZTEXTURE_DISABLE;
+    return ztexture_enabled;
   }
   else
   {
     // We need a full depth range if a ztexture is used.
-    if (bpmem.ztex2.type != ZTEXTURE_DISABLE)
+    if (ztexture_enabled)
       return true;
 
     // If an inverted depth range is unsupported, we also need to check if the range is inverted.