From cbed4624faeb4b192f908b1a2a66b7f3744fb32a Mon Sep 17 00:00:00 2001
From: Christoph Oelckers <coelckers@zdoom.fake>
Date: Fri, 29 Nov 2013 13:24:38 +0100
Subject: [PATCH] - added a user-settable factor for earthquake intensity.
 Value can be between 0 (no shaking) and 1 (normal shaking.)

---
 src/r_utility.cpp         | 13 +++++++++----
 wadsrc/static/menudef.txt |  1 +
 2 files changed, 10 insertions(+), 4 deletions(-)

diff --git a/src/r_utility.cpp b/src/r_utility.cpp
index 606cca840..356bfe741 100644
--- a/src/r_utility.cpp
+++ b/src/r_utility.cpp
@@ -89,6 +89,11 @@ CVAR (Bool, r_deathcamera, false, CVAR_ARCHIVE)
 CVAR (Int, r_clearbuffer, 0, 0)
 CVAR (Bool, r_drawvoxels, true, 0)
 CVAR (Bool, r_drawplayersprites, true, 0)	// [RH] Draw player sprites?
+CUSTOM_CVAR(Float, r_quakeintensity, 1.0f, CVAR_ARCHIVE | CVAR_GLOBALCONFIG)
+{
+	if (self < 0.f) self = 0.f;
+	else if (self > 1.f) self = 1.f;
+}
 
 DCanvas			*RenderTarget;		// [RH] canvas to render to
 
@@ -837,10 +842,10 @@ void R_SetupFrame (AActor *actor)
 		int intensity = DEarthquake::StaticGetQuakeIntensity (camera);
 		if (intensity != 0)
 		{
-			viewx += ((pr_torchflicker() % (intensity<<2))
-						-(intensity<<1))<<FRACBITS;
-			viewy += ((pr_torchflicker() % (intensity<<2))
-						-(intensity<<1))<<FRACBITS;
+			fixed_t quakefactor = FLOAT2FIXED(r_quakeintensity);
+
+			viewx += quakefactor * ((pr_torchflicker() % (intensity<<2)) - (intensity<<1));
+			viewy += quakefactor * ((pr_torchflicker() % (intensity<<2)) - (intensity<<1));
 		}
 	}
 
diff --git a/wadsrc/static/menudef.txt b/wadsrc/static/menudef.txt
index 6457051bf..71aeb9ae5 100644
--- a/wadsrc/static/menudef.txt
+++ b/wadsrc/static/menudef.txt
@@ -686,6 +686,7 @@ OptionMenu "VideoOptions"
 	Option "Show player sprites",		"r_drawplayersprites", "OnOff"
 	Option "Death camera",				"r_deathcamera", "OnOff"
 	Option "Teleporter zoom",			"telezoom", "OnOff"
+	Slider "Earthquake shake intensity",	"r_quakeintensity", 0.0, 1.0, 0.05, 2
 	Option "Interpolate monster movement",	"nomonsterinterpolation", "NoYes"
 }