From 4f1aa7c5cf353c8952fa0c5fc424a3aba57f7d5f Mon Sep 17 00:00:00 2001
From: Sven Eberhardt <sven2@goldwipf.de>
Date: Tue, 5 Aug 2014 17:01:37 +0200
Subject: [PATCH] Destroy single pixels of non-diggable material [ala]

---
 planet/Material.ocg/Vehicle.ocm | 2 +-
 src/landscape/C4Landscape.cpp   | 8 +++++---
 src/landscape/C4Material.cpp    | 2 ++
 src/landscape/C4Material.h      | 1 +
 4 files changed, 9 insertions(+), 4 deletions(-)

diff --git a/planet/Material.ocg/Vehicle.ocm b/planet/Material.ocg/Vehicle.ocm
index 3d078e365..43e981e19 100644
--- a/planet/Material.ocg/Vehicle.ocm
+++ b/planet/Material.ocg/Vehicle.ocm
@@ -2,4 +2,4 @@
 Name=Vehicle
 Density=100
 Friction=100
- 
+KeepSinglePixels=1
diff --git a/src/landscape/C4Landscape.cpp b/src/landscape/C4Landscape.cpp
index f9dda50b4..baaa63067 100644
--- a/src/landscape/C4Landscape.cpp
+++ b/src/landscape/C4Landscape.cpp
@@ -756,14 +756,16 @@ bool C4Landscape::CheckInstability(int32_t tx, int32_t ty, int32_t recursion_cou
 {
 	int32_t mat=GetMat(tx,ty);
 	if (MatValid(mat)) {
-		if (::MaterialMap.Map[mat].Instable)
+		const C4Material &material = MaterialMap.Map[mat];
+		if (material.Instable)
 			return ::MassMover.Create(tx,ty);
 		// Get rid of single pixels
-		else if (::MaterialMap.Map[mat].DigFree && recursion_count<10) 
+		else if (DensitySolid(material.Density) && !material.KeepSinglePixels && recursion_count<10) 
 			if ((!::GBackSolid(tx,ty+1)) + (!::GBackSolid(tx,ty-1)) + (!::GBackSolid(tx+1,ty)) + (!::GBackSolid(tx-1,ty)) >= 3)
 			{
 				if (!ClearPix(tx,ty)) return false;
-				::PXS.Create(mat,itofix(tx),itofix(ty));
+				// Diggable material drops; other material just gets removed
+				if (material.DigFree) ::PXS.Create(mat,itofix(tx),itofix(ty));
 				// check other pixels around this
 				// Note this cannot lead to an endless recursion (unless you do funny stuff like e.g. set DigFree=1 in material Tunnel).
 				// Check recursion anyway, because very large strips of single pixel width might cause sufficient recursion to crash
diff --git a/src/landscape/C4Material.cpp b/src/landscape/C4Material.cpp
index 469a8b06e..5419e5b08 100644
--- a/src/landscape/C4Material.cpp
+++ b/src/landscape/C4Material.cpp
@@ -265,6 +265,7 @@ void C4MaterialCore::Clear()
 	TempConvStrength = 0;
 	MinHeightCount = 0;
 	SplashRate=10;
+	KeepSinglePixels=false;
 }
 
 void C4MaterialCore::Default()
@@ -364,6 +365,7 @@ void C4MaterialCore::CompileFunc(StdCompiler *pComp)
 	                                                "BelowTempConvertTo",  ""));
 	pComp->Value(mkNamingAdapt(MinHeightCount,      "MinHeightCount",      0));
 	pComp->Value(mkNamingAdapt(SplashRate,          "SplashRate",          10));
+	pComp->Value(mkNamingAdapt(KeepSinglePixels,    "KeepSinglePixels",    false));
 	pComp->NameEnd();
 	// material reactions
 	pComp->Value(mkNamingAdapt(mkSTLContainerAdapt(CustomReactionList),
diff --git a/src/landscape/C4Material.h b/src/landscape/C4Material.h
index 45e60febb..b8cc0a28d 100644
--- a/src/landscape/C4Material.h
+++ b/src/landscape/C4Material.h
@@ -178,6 +178,7 @@ public:
 	int32_t  TempConvStrength;
 	int32_t  MinHeightCount; // minimum material thickness in order for it to be counted
 	int32_t  SplashRate;
+	bool KeepSinglePixels; // if true, single pixels are not destroyed (for vehicle)
 
 	void Clear();
 	void Default();