From e0b2497a5621e8bfc64c8ccf57c68ca99328e8a8 Mon Sep 17 00:00:00 2001
From: Christoph Oelckers <coelckers@users.noreply.github.com>
Date: Tue, 21 Apr 2020 21:26:33 +0200
Subject: [PATCH] - backend update.

---
 source/common/2d/v_draw.cpp       |  6 ++++++
 source/common/2d/v_draw.h         | 36 +++++++++++++++++++++++++++++++
 source/core/rendering/v_video.cpp |  6 ------
 source/core/rendering/v_video.h   |  4 ----
 4 files changed, 42 insertions(+), 10 deletions(-)

diff --git a/source/common/2d/v_draw.cpp b/source/common/2d/v_draw.cpp
index a85f1ac8a..bf33d6f6a 100644
--- a/source/common/2d/v_draw.cpp
+++ b/source/common/2d/v_draw.cpp
@@ -1384,3 +1384,9 @@ void DrawFrame(F2DDrawer* twod, PalEntry color, int left, int top, int width, in
 	twod->AddColorOnlyQuad(right, top - offset, offset, height + 2 * offset, color);
 }
 
+void V_CalcCleanFacs(int designwidth, int designheight, int realwidth, int realheight, int* cleanx, int* cleany, int* _cx1, int* _cx2)
+{
+	if (designheight < 240 && realheight >= 480) designheight = 240;
+	*cleanx = *cleany = std::min(realwidth / designwidth, realheight / designheight);
+}
+
diff --git a/source/common/2d/v_draw.h b/source/common/2d/v_draw.h
index e42b6f306..fe76272f5 100644
--- a/source/common/2d/v_draw.h
+++ b/source/common/2d/v_draw.h
@@ -233,3 +233,39 @@ void VirtualToRealCoordsInt(F2DDrawer* drawer, int& x, int& y, int& w, int& h, i
 
 extern int CleanWidth, CleanHeight, CleanXfac, CleanYfac;
 extern int CleanWidth_1, CleanHeight_1, CleanXfac_1, CleanYfac_1;
+
+void V_CalcCleanFacs(int designwidth, int designheight, int realwidth, int realheight, int* cleanx, int* cleany, int* cx1 = NULL, int* cx2 = NULL);
+
+class ScaleOverrider
+{
+	int savedxfac, savedyfac, savedwidth, savedheight;
+
+public:
+	// This is to allow certain elements to use an optimal fullscreen scale which for the menu would be too large.
+	// The old code contained far too much mess to compensate for the menus which negatively affected everything else.
+	// However, for compatibility reasons the currently used variables cannot be changed so they have to be overridden temporarily.
+	// This class provides a safe interface for this because it ensures that the values get restored afterward.
+	// Currently, the intermission and the level summary screen use this.
+	ScaleOverrider(F2DDrawer *drawer)
+	{
+		savedxfac = CleanXfac;
+		savedyfac = CleanYfac;
+		savedwidth = CleanWidth;
+		savedheight = CleanHeight;
+
+		if (drawer)
+		{
+			V_CalcCleanFacs(320, 200, drawer->GetWidth(), drawer->GetHeight(), &CleanXfac, &CleanYfac);
+			CleanWidth = drawer->GetWidth() / CleanXfac;
+			CleanHeight = drawer->GetHeight() / CleanYfac;
+		}
+	}
+
+	~ScaleOverrider()
+	{
+		CleanXfac = savedxfac;
+		CleanYfac = savedyfac;
+		CleanWidth = savedwidth;
+		CleanHeight = savedheight;
+	}
+};
diff --git a/source/core/rendering/v_video.cpp b/source/core/rendering/v_video.cpp
index b8e4d22fa..85c0d799f 100644
--- a/source/core/rendering/v_video.cpp
+++ b/source/core/rendering/v_video.cpp
@@ -298,12 +298,6 @@ void V_OutputResized (int width, int height)
 	C_NewModeAdjust();
 }
 
-void V_CalcCleanFacs (int designwidth, int designheight, int realwidth, int realheight, int *cleanx, int *cleany, int *_cx1, int *_cx2)
-{
-	if (designheight < 240 && realheight >= 480) designheight = 240;
-	*cleanx = *cleany = std::min(realwidth / designwidth, realheight / designheight);
-}
-
 bool IVideo::SetResolution ()
 {
 	DFrameBuffer *buff = CreateFrameBuffer();
diff --git a/source/core/rendering/v_video.h b/source/core/rendering/v_video.h
index aefb66f09..26aa349b3 100644
--- a/source/core/rendering/v_video.h
+++ b/source/core/rendering/v_video.h
@@ -38,9 +38,6 @@
 #include "basics.h"
 #include "vectors.h"
 #include "m_png.h"
-
-//#include "doomdef.h"
-//#include "dobject.h"
 #include "renderstyle.h"
 #include "c_cvars.h"
 #include "v_2ddrawer.h"
@@ -118,7 +115,6 @@ extern int DisplayWidth, DisplayHeight;
 
 void V_UpdateModeSize (int width, int height);
 void V_OutputResized (int width, int height);
-void V_CalcCleanFacs (int designwidth, int designheight, int realwidth, int realheight, int *cleanx, int *cleany, int *cx1=NULL, int *cx2=NULL);
 
 EXTERN_CVAR(Int, vid_rendermode)
 EXTERN_CVAR(Bool, vid_fullscreen)