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

@@ -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;
   }

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;
   }

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);
 }
 

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;
   }