Changed: "Unable to save the map: there are too many unique sidedefs!" error message now displays info about sidedefs counts before and after sidedef compression.

Fixed, Draw Grid mode: in some cases invalid geometry was created when drawing very large grids.
Fixed, Things mode, "Rotate Clockwise" action: fixed inability to change thing angle from 0 to 315 when "doomthingrotationangles" Game Configuration property was set to true.
Updated ZDoom_DECORATE.cfg.

Build/Scripting/ZDoom_DECORATE.cfg

@@ -120,7 +120,7 @@ keywords
 //Generic monster attacks
 	A_CustomMissile = "A_CustomMissile(str missiletype[, float spawnheight = 32.0[, float spawnofs_horiz = 0.0[, int angle = 0[, int aimflags = 0[, int pitch = 0[, int target = AAPTR_TARGET]]]]]])";
 	A_CustomBulletAttack = "A_CustomBulletAttack(float horz_spread, float vert_spread, int numbullets, int damageperbullet[, str pufftype = \"BulletPuff\"[, float range = 0.0[, int flags = 0[, int target = AAPTR_TARGET]]]])";
-	A_CustomRailgun = "A_CustomRailgun(int damage[, int offset[, color ringcolor[, color corecolor[, int flags = 0[, bool aim = false[, float maxdiff = 0.0[, str pufftype = \"\"[, float spread_xy = 0.0[, float spread_z = 0.0[, float range = 8192[, int duration = 35[, float sparsity = 1.0[, float driftspeed = 1.0[, str spawnclass = \"\"[, float spawnofs_z = 0[, int spiraloffset = 270]]]]]]]]]]]]]]]])";
+	A_CustomRailgun = "A_CustomRailgun(int damage[, int offset[, color ringcolor[, color corecolor[, int flags = 0[, bool aim = false[, float maxdiff = 0.0[, str pufftype = \"\"[, float spread_xy = 0.0[, float spread_z = 0.0[, float range = 8192[, int duration = 35[, float sparsity = 1.0[, float driftspeed = 1.0[, str spawnclass = \"\"[, float spawnofs_z = 0[, int spiraloffset = 270[, int actorpiercelimit = 0]]]]]]]]]]]]]]]]])";
 	A_CustomMeleeAttack = "A_CustomMeleeAttack[(int damage = 0[, str meleesound = \"\"[, str misssound = \"\"[, str damagetype = \"Melee\"[, bool bleed = true]]]])]";
 	A_CustomComboAttack = "A_CustomComboAttack(str missiletype, float spawnheight, int damage, str meleesound[, str damagetype = \"Melee\"[, bool bleed = true]])";
 	A_MonsterRefire = "state A_MonsterRefire(int chancecontinue, str abortstate)";
@@ -292,6 +292,7 @@ keywords
 	A_RadiusGive = "int A_RadiusGive(str item, float distance, int flags[, int amount = 0[, str filter = \"None\"[, str species = \"None\"[, int mindist = 0[, int limit = 0]]]]])\nflags: RGF flags.";
 //Weapon functions
 	A_WeaponReady = "A_WeaponReady[(int flags = 0)]\nflags: WRF flags.";
+	A_WeaponOffset = "A_WeaponOffset[(float x = 0[, float y = 32[, int flags = 0])]\nflags: WOF flags.";
 	A_Lower = "A_Lower";
 	A_Raise = "A_Raise";
 	A_ReFire = "A_ReFire[(str state = \"Hold\")]";
@@ -305,17 +306,19 @@ keywords
 	A_Light1 = "A_Light1";
 	A_Light2 = "A_Light2";
 	A_LightInverse = "A_LightInverse";
+	A_Overlay = "A_Overlay(int layer[, state start])";
+	A_OverlayFlags = "A_OverlayFlags(int layer, int flags, bool set)\nflags: PSPF flags.";
+	A_OverlayOffset = "A_OverlayOffset[(int layer = 0[, float x = 0.0f[, float y = 32.0f[, int flags = 0]]]])]\nflags: WOF flags.";
 	A_Recoil = "A_Recoil(float force)";
 	A_ZoomFactor = "A_ZoomFactor[(float zoom = 1.0[, int flags = 0])]\nflags: ZOOM flags.";
 	A_SetCrosshair = "A_SetCrosshair(int number)";
-	A_WeaponOffset = "A_WeaponOffset[(float x = 0[, float y = 32[, int flags = 0])]\nflags: WOF flags.";
 //Weapon attack functions
 	A_Punch = "A_Punch";
 	A_Saw = "A_Saw[(str fullsound = \"weapons/sawfull\"[, str hitsound = \"weapons/sawhit\"[, int damage = 0[, str pufftype = \"BulletPuff\"[, int flags = 0[, float range = 65.0[, float spread_xy = 2.8125[, float spread_z = 0.0[, float lifesteal = 0.0[, int lifestealmax = 0[, str armorbonustype = \"ArmorBonus\"]]]]]]]]]])]";
 	A_CustomPunch = "A_CustomPunch(int damage[, bool norandom = false[, int flags = 0[, str pufftype = \"BulletPuff\"[, float range = 64.0[, float lifesteal = 0.0[, int lifestealmax = 0[, str armorbonustype = \"ArmorBonus\"[, str meleesound[, str misssound]]]]]]]]])";
 	A_FireBullets = "A_FireBullets(int spread_horz, int spread_vert, int numbullets, int damage[, str pufftype = \"\"[, int flags = FBF_USEAMMO[, float range = 0.0]]])";
 	A_FireCustomMissile = "A_FireCustomMissile(str missiletype[, int angle = 0[, bool useammo = false[, float spawnofs_horz = 0.0[, int spawnheight = 0[, int flags = 0[, angle pitch = 0]]]]]])";
-	A_RailAttack = "A_RailAttack(int damage[, int spawnofs_horz[, bool useammo[, str ringcolor[, str corecolor[, int flags[, int maxdiff[, str pufftype[, float spread_xy = 0.0[, float spread_z = 0.0[, float range = 8192.0[, int duration = 35[, float sparsity = 1.0[, float driftspeed = 1.0[, str spawnclass[, float spawnofs_z = 0.0[, int spiraloffset = 270]]]]]]]]]]]]]]]])";
+	A_RailAttack = "A_RailAttack(int damage[, int spawnofs_horz[, bool useammo[, str ringcolor[, str corecolor[, int flags[, int maxdiff[, str pufftype[, float spread_xy = 0.0[, float spread_z = 0.0[, float range = 8192.0[, int duration = 35[, float sparsity = 1.0[, float driftspeed = 1.0[, str spawnclass[, float spawnofs_z = 0.0[, int spiraloffset = 270[, int actorpiercelimit = 0]]]]]]]]]]]]]]]]])";
 	A_FireAssaultGun = "A_FireAssaultGun";
 	A_FireBFG = "A_FireBFG";
 	A_FireOldBFG = "A_FireOldBFG";
@@ -1359,4 +1362,9 @@ constants
 	WOF_KEEPX;
 	WOF_KEEPY;
 	WOF_ADD;
+//A_OverlayFlags flags
+	PSPF_ADDWEAPON;
+	PSPF_ADDBOB;
+	PSPF_POWDOUBLE;
+	PSPF_CVARFAST;	
 }

Source/Core/General/MapManager.cs

@@ -662,6 +662,7 @@ namespace CodeImp.DoomBuilder
 			if(map.Sidedefs.Count > io.MaxSidedefs)
 			{
 				// Compress sidedefs
+				int initialsidescount = outputset.Sidedefs.Count; //mxd
 				General.MainWindow.DisplayStatus(StatusType.Busy, "Compressing sidedefs...");
 				outputset.CompressSidedefs();
 
@@ -669,7 +670,9 @@ namespace CodeImp.DoomBuilder
 				if(outputset.Sidedefs.Count > io.MaxSidedefs)
 				{
 					// Problem! Can't save the map like this!
-					General.ShowErrorMessage("Unable to save the map: There are too many unique sidedefs!", MessageBoxButtons.OK);
+					General.ShowErrorMessage("Unable to save the map: there are too many unique sidedefs!" + Environment.NewLine + Environment.NewLine
+						+ "Sidedefs before compresion: " + initialsidescount + Environment.NewLine
+						+ "Sidedefs after compresion: " + outputset.Sidedefs.Count, MessageBoxButtons.OK);
 					General.MainWindow.DisplayStatus(oldstatus);
 					return false;
 				}

Source/Core/Geometry/Tools.cs

@@ -937,6 +937,7 @@ namespace CodeImp.DoomBuilder.Geometry
 				if(points[0].stitch) mergeverts.Add(v1); else nonmergeverts.Add(v1);
 
 				// Go for all other points
+				int roundprecision = (General.Map.FormatInterface.VertexDecimals > 0 ? General.Map.FormatInterface.VertexDecimals - 1 : 0); //mxd
 				for(int i = 1; i < points.Count; i++)
 				{
 					// Create vertex for point
@@ -999,6 +1000,10 @@ namespace CodeImp.DoomBuilder.Geometry
 							// may already have changed in length due to a previous split
 							Vector2D splitpoint = measureline.GetCoordinatesAt(u);
 
+							//mxd. Work around some imprecisions when splitting very long lines (like 19000 mu long)
+							splitpoint.x = (float)Math.Round(splitpoint.x, roundprecision);
+							splitpoint.y = (float)Math.Round(splitpoint.y, roundprecision);
+
 							// Make the vertex
 							Vertex splitvertex = map.CreateVertex(splitpoint);
 							if(splitvertex == null) return false;

Source/Plugins/BuilderModes/ClassicModes/DrawGridMode.cs

@@ -364,7 +364,8 @@ namespace CodeImp.DoomBuilder.BuilderModes
 					int step = width / slicesH;
 					for(int w = 0; w < slicesH; w++)
 					{
-						shapes.Add(new[] { new Vector2D((int)s.x + step * w, (int)s.y), new Vector2D((int)s.x + step * w + step, (int)s.y) });
+						shapes.Add(new[] { new Vector2D((float)Math.Round(s.x + step * w), (float)Math.Round(s.y)), 
+										   new Vector2D((float)Math.Round(s.x + step * w + step), (float)Math.Round(s.y)) });
 					}
 					return shapes;
 				}
@@ -375,7 +376,8 @@ namespace CodeImp.DoomBuilder.BuilderModes
 					int step = height / slicesV;
 					for(int h = 0; h < slicesV; h++)
 					{
-						shapes.Add(new[] {new Vector2D((int) s.x, (int) s.y + step * h), new Vector2D((int) s.x, (int) s.y + step * h + step)});
+						shapes.Add(new[] { new Vector2D((float)Math.Round(s.x), (float)Math.Round(s.y + step * h)), 
+										   new Vector2D((float)Math.Round(s.x), (float)Math.Round(s.y + step * h + step)) });
 					}
 					return shapes;
 				}
@@ -384,7 +386,7 @@ namespace CodeImp.DoomBuilder.BuilderModes
 				return new List<Vector2D[]> {new[] {s, e}};
 			}
 
-			// Create shape
+			// Create grid shape
 			List<Vector2D> rect = new List<Vector2D> { s, new Vector2D((int)s.x, (int)e.y), e, new Vector2D((int)e.x, (int)s.y), s };
 			if(slicesH == 1 && slicesV == 1) 
 			{
@@ -397,7 +399,7 @@ namespace CodeImp.DoomBuilder.BuilderModes
 			RectangleF[,] blocks = new RectangleF[slicesH, slicesV];
 			for(int w = 0; w < slicesH; w++) 
 			{
-				for(int h = 0; h < slicesV; h++) 
+				for(int h = 0; h < slicesV; h++)
 				{
 					float left = (float)Math.Round(InterpolationTools.Interpolate(s.x, e.x, (float)w / slicesH, horizontalinterpolation));
 					float top = (float)Math.Round(InterpolationTools.Interpolate(s.y, e.y, (float)h / slicesV, verticalinterpolation));
@@ -412,15 +414,15 @@ namespace CodeImp.DoomBuilder.BuilderModes
 			{
 				for(int w = 1; w < slicesH; w++) 
 				{
-					int px = (int) Math.Round(blocks[w, 0].X);
+					float px = (float)Math.Round(blocks[w, 0].X);
-					shapes.Add(new[] {new Vector2D(px, s.y), new Vector2D(px, e.y)});
+					shapes.Add(new[] { new Vector2D(px, s.y), new Vector2D(px, e.y) });
 				}
 			}
 			if(slicesV > 1) 
 			{
 				for(int h = 1; h < slicesV; h++) 
 				{
-					int py = (int) Math.Round(blocks[0, h].Y);
+					float py = (float)Math.Round(blocks[0, h].Y);
 					shapes.Add(new[] { new Vector2D(s.x, py), new Vector2D(e.x, py) });
 				}
 			}

Source/Plugins/BuilderModes/ClassicModes/ThingsMode.cs

@@ -1576,8 +1576,7 @@ namespace CodeImp.DoomBuilder.BuilderModes
 			foreach(Thing t in selected)
 			{
 				int newangle = t.AngleDoom + increment;
-				if(General.Map.Config.DoomThingRotationAngles) newangle = (newangle + 22) / 45 * 45;
+				if(General.Map.Config.DoomThingRotationAngles) newangle = newangle / 45 * 45;
-
 				t.Rotate(General.ClampAngle(newangle));
 			}