From 66f1ac2abc2a201b8cbc41a3a85fb95b2c60d26a Mon Sep 17 00:00:00 2001
From: OV2 <OV2@sessionclan.de>
Date: Mon, 20 May 2019 21:13:32 +0200
Subject: [PATCH] win32: reset d3d viewport before clearing (#531)

---
 win32/CDirect3D.cpp | 28 +++++++++++++++++++++++++---
 win32/CDirect3D.h   |  1 +
 2 files changed, 26 insertions(+), 3 deletions(-)

diff --git a/win32/CDirect3D.cpp b/win32/CDirect3D.cpp
index 7d2fbc64..40b7f5a5 100644
--- a/win32/CDirect3D.cpp
+++ b/win32/CDirect3D.cpp
@@ -134,7 +134,7 @@ bool CDirect3D::Initialize(HWND hWnd)
 	pDevice->SetSamplerState(0, D3DSAMP_ADDRESSU, D3DTADDRESS_BORDER);
 	pDevice->SetSamplerState(0, D3DSAMP_ADDRESSV, D3DTADDRESS_BORDER);
 
-	pDevice->Clear(0, NULL, D3DCLEAR_TARGET, D3DCOLOR_XRGB(0, 0, 0), 1.0f, 0);
+	Clear();
 
 	init_done = true;
 
@@ -298,8 +298,9 @@ void CDirect3D::Render(SSurface Src)
 		drawSurface->UnlockRect(0);
 	}
 
-	if(!GUI.Stretch||GUI.AspectRatio)
-		pDevice->Clear(0, NULL, D3DCLEAR_TARGET, D3DCOLOR_XRGB(0, 0, 0), 1.0f, 0);
+	if (!GUI.Stretch || GUI.AspectRatio) {
+		Clear();
+	}
 
 	//if the output size of the render method changes we need to update the viewport
 	if(afterRenderHeight != dstRect.bottom || afterRenderWidth != dstRect.right) {
@@ -687,3 +688,24 @@ void CDirect3D::SetFiltering()
 		pDevice->SetSamplerState(0, D3DSAMP_MINFILTER, D3DTEXF_POINT);
 	}
 }
+
+// reset viewport to whole window, clear, set back to current viewport
+void CDirect3D::Clear()
+{
+	if (!init_done)
+		return;
+
+	D3DVIEWPORT9 vp_current, vp_all;
+	pDevice->GetViewport(&vp_current);
+
+	vp_all.X = 0;
+	vp_all.Y = 0;
+	vp_all.Width = dPresentParams.BackBufferWidth;
+	vp_all.Height = dPresentParams.BackBufferHeight;
+	vp_all.MinZ = 0.0;
+	vp_all.MaxZ = 1.0;
+
+	pDevice->SetViewport(&vp_all);
+	pDevice->Clear(0, NULL, D3DCLEAR_TARGET, D3DCOLOR_XRGB(0, 0, 0), 1.0f, 0);
+	pDevice->SetViewport(&vp_current);
+}
diff --git a/win32/CDirect3D.h b/win32/CDirect3D.h
index 7d9e939b..c8f65c31 100644
--- a/win32/CDirect3D.h
+++ b/win32/CDirect3D.h
@@ -76,6 +76,7 @@ private:
 	bool SetShader(const TCHAR *file);
 	void checkForCgError(const char *situation);
 	bool SetShaderCG(const TCHAR *file);
+	void Clear();
 
 public:
 	CDirect3D();