From 5399995c611f6ae4197baca2cd5e3746f4827d1e Mon Sep 17 00:00:00 2001
From: Stenzek <stenzek@gmail.com>
Date: Sun, 28 Apr 2019 16:01:07 +1000
Subject: [PATCH] Vulkan: Don't set a negative offset in scissor rect

The spec/validation layers say this is invalid.
---
 Source/Core/VideoBackends/Vulkan/Renderer.cpp | 13 +++++++++++++
 1 file changed, 13 insertions(+)

diff --git a/Source/Core/VideoBackends/Vulkan/Renderer.cpp b/Source/Core/VideoBackends/Vulkan/Renderer.cpp
index 8d702adb45..ac3dbe4c2a 100644
--- a/Source/Core/VideoBackends/Vulkan/Renderer.cpp
+++ b/Source/Core/VideoBackends/Vulkan/Renderer.cpp
@@ -561,6 +561,19 @@ void Renderer::SetScissorRect(const MathUtil::Rectangle<int>& rc)
 {
   VkRect2D scissor = {{rc.left, rc.top},
                       {static_cast<u32>(rc.GetWidth()), static_cast<u32>(rc.GetHeight())}};
+
+  // See Vulkan spec for vkCmdSetScissor:
+  // The x and y members of offset must be greater than or equal to 0.
+  if (scissor.offset.x < 0)
+  {
+    scissor.extent.width -= -scissor.offset.x;
+    scissor.offset.x = 0;
+  }
+  if (scissor.offset.y < 0)
+  {
+    scissor.extent.height -= -scissor.offset.y;
+    scissor.offset.y = 0;
+  }
   StateTracker::GetInstance()->SetScissor(scissor);
 }