Implemented "six degrees of freedom" movement for guided redeemer missiles (reload/zoom for manual tilt control).

Made part of the guided redeemer reticle rotate according to the missile's roll just to show off Shape2D.

zscript.txt

@@ -2,6 +2,7 @@ version "3.4"
 
 #include "zscript/mk_matrix.zsc"
 #include "zscript/mk_coordutil.zsc"
+#include "zscript/mk_quaternion.zsc"
 #include "zscript/utcommon.zsc"
 #include "zscript/impacthammer.zsc"
 #include "zscript/chainsaw.zsc"

zscript/mk_quaternion.zsc

@@ -0,0 +1,97 @@
+/*
+   Quaternion math helper class.
+   (C)2018 Marisa Kirisame, UnSX Team.
+   Released under the GNU Lesser General Public License version 3 (or later).
+   See https://www.gnu.org/licenses/lgpl-3.0.txt for its terms.
+*/
+
+Class Quat
+{
+	protected double W, X, Y, Z;
+
+	Quat init( double w, double x, double y, double z )
+	{
+		self.W = w;
+		self.X = x;
+		self.Y = y;
+		self.Z = z;
+		return self;
+	}
+
+	void copy( Quat q )
+	{
+		W = q.W;
+		X = q.X;
+		Y = q.Y;
+		Z = q.Z;
+	}
+
+	static Quat create( double w, double x, double y, double z )
+	{
+		return new("Quat").init(w,x,y,z);
+	}
+
+	static Quat create_axis( Vector3 axis, double theta )
+	{
+		double scale = axis dot axis;
+		if ( scale < double.epsilon ) return Quat.create(1,0,0,0);
+		theta *= 0.5;
+		double f = sin(theta)/sqrt(scale);
+		return Quat.create(cos(theta),axis.x*f,axis.y*f,axis.z*f);
+	}
+
+	static Quat create_euler( double pitch, double yaw, double roll )
+	{
+		Quat zrot = Quat.create_axis((0,0,1),yaw);
+		Quat yrot = Quat.create_axis((0,1,0),pitch);
+		Quat xrot = Quat.create_axis((1,0,0),roll);
+		Quat sum = zrot.qmul(yrot);
+		sum = sum.qmul(xrot);
+		return sum;
+	}
+
+	// copied here since Actor.Normalize180 is not (yet) clearscope
+	static double Normalize180( double ang )
+	{
+		ang = ang%360;
+		ang = (ang+360)%360;
+		if ( ang > 180 ) ang -= 360;
+		return ang;
+	}
+
+	double, double, double to_euler()
+	{
+		double stest = z*x-w*y;
+		double yawY = 2*(w*z+x*y);
+		double yawX = 1-2*(y*y+z*z);
+		double st = 0.4999995;
+		double pitch = 0;
+		double yaw = 0;
+		double roll = 0;
+		if ( stest <= -st )
+		{
+			pitch = 90;
+			yaw = atan2(yawY,yawX);
+			roll = Normalize180(yaw+(2*atan2(x,w)));
+		}
+		else if ( stest > st )
+		{
+			pitch = -90;
+			yaw = atan2(yawY,yawX);
+			roll = Normalize180(yaw+(2*atan2(x,w)));
+		}
+		else
+		{
+			pitch = -asin(2*stest);
+			yaw = atan2(yawY,yawX);
+			roll = atan2(2*(w*x+y*z),(1-2*(x*x+y*y)));
+		}
+		return pitch, yaw, roll;
+	}
+
+	Quat qmul( Quat q )
+	{
+		return Quat.create(w*q.w-x*q.x-y*q.y-z*q.z,w*q.x+x*q.w+y*q.z-z
+			*q.y,w*q.y+y*q.w+z*q.x-x*q.z,w*q.z+z*q.w+x*q.y-y*q.x);
+	}
+}

zscript/warheadlauncher.zsc

@@ -355,15 +355,13 @@ Class WarShell : Actor
 
 Class GuidedWarShell : WarShell
 {
-	double lagangle, lagpitch, lagangle2, lagpitch2;
-	double guideangle, guidepitch, lastguideroll;
+	double lagangle, lagpitch, lagroll, lagangle2, lagpitch2, lagroll2,
+		guideangle, guidepitch, guideroll;
 
 	override void PostBeginPlay()
 	{
 		Super.PostBeginPlay();
 		if ( target && target.player ) target.player.camera = self;
-		guideangle = angle;
-		guidepitch = pitch;
 	}
 	override void Tick()
 	{
@@ -385,22 +383,25 @@ Class GuidedWarShell : WarShell
 		{
 			lagangle = target.player.cmd.yaw/128.;
 			lagpitch = -target.player.cmd.pitch/128.;
-			guideangle += lagangle2*0.95+lagangle*0.05;
-			guidepitch += lagpitch2*0.95+lagpitch*0.05;
-			guidepitch = Clamp(guidepitch,-89,89);
-			double guideroll = -lagangle2*15;
-			Vector3 dir = (cos(guideangle)*cos(guidepitch),sin(guideangle)*cos(guidepitch),-sin(guidepitch));
-			destangle = atan2(dir.y,dir.x);
-			destpitch = asin(-dir.z);
-			double destroll = lastguideroll*0.9+guideroll*0.1;
-			A_SetAngle(destangle,SPF_INTERPOLATE);
-			A_SetPitch(destpitch,SPF_INTERPOLATE);
-			A_SetRoll(destroll,SPF_INTERPOLATE);
+			if ( target.player.cmd.buttons&BT_RELOAD ) lagroll = 5;
+			else if ( target.player.cmd.buttons&BT_ZOOM ) lagroll = -5;
+			else lagroll = 0;
+			guideangle = lagangle2*0.95+lagangle*0.05;
+			guidepitch = lagpitch2*0.95+lagpitch*0.05;
+			guideroll = lagroll2*0.95+lagroll*0.05;
+			Quat orient = Quat.create_euler(pitch,angle,roll);
+			Quat angles = Quat.create_euler(guidepitch,guideangle,guideroll);
+			orient = orient.qmul(angles);
+			double npitch, nangle, nroll;
+			[npitch, nangle, nroll] = orient.to_euler();
+			A_SetAngle(nangle,SPF_INTERPOLATE);
+			A_SetPitch(npitch,SPF_INTERPOLATE);
+			A_SetRoll(nroll,SPF_INTERPOLATE);
 			vel = (vel+(cos(angle)*cos(pitch),sin(angle)*cos(pitch),-sin(pitch))*0.8).unit()*11;
 		}
 		lagangle2 = lagangle2*0.95+lagangle*0.05;
 		lagpitch2 = lagpitch2*0.95+lagpitch*0.05;
-		lastguideroll = roll*0.98;
+		lagroll2 = lagroll2*0.95+lagroll*0.05;
 	}
 	States
 	{
@@ -439,25 +440,36 @@ Class RedeemerHUD : HUDMessageBase
 {
 	Actor Camera;
 	Vector3 ViewPos;
-	double ViewAngle, ViewPitch, ViewRoll;
-	TextureID reticle, mark, readout;
+	double ViewAngle, ViewPitch, ViewRoll, LagRoll, LagRoll2;
+	TextureID reticle1, reticle2, mark, readout;
 	Font whfont;
 	ThinkerIterator t;
 	MidTracer tr;
 	Array<TargetActor> ta;
+	Shape2D rreticle;
 
 	RedeemerHUD Init()
 	{
-		reticle = TexMan.CheckForTexture("GuidedX",TexMan.Type_Any);
+		reticle1 = TexMan.CheckForTexture("GuidedX1",TexMan.Type_Any);
+		reticle2 = TexMan.CheckForTexture("GuidedX2",TexMan.Type_Any);
 		mark = TexMan.CheckForTexture("Crosshr6",TexMan.Type_Any);
 		readout = TexMan.CheckForTexture("Readout",TexMan.Type_Any);
 		whfont = Font.GetFont('WHFONT');
 		t = ThinkerIterator.Create("Actor");
 		tr = new("MidTracer");
+		rreticle = new("Shape2D");
+		rreticle.PushCoord((0,0));
+		rreticle.PushCoord((1,0));
+		rreticle.PushCoord((0,1));
+		rreticle.PushCoord((1,1));
+		rreticle.PushTriangle(0,3,1);
+		rreticle.PushTriangle(0,2,3);
 		return self;
 	}
 	override bool Tick()
 	{
+		LagRoll = Quat.Normalize180(ViewRoll-LagRoll2);
+		LagRoll2 += Quat.Normalize180(LagRoll-LagRoll2)*0.1;
 		// shootable targetting
 		if ( CVar.GetCVar('flak_redeemerreadout',players[consoleplayer]).GetBool() )
 		{
@@ -494,8 +506,21 @@ Class RedeemerHUD : HUDMessageBase
 				Screen.DrawText(whfont,Font.CR_UNTRANSLATED,(ta[i].vpos.x-whfont.StringWidth(ta[i].diststr)/2)-12,ta[i].vpos.y+8,ta[i].diststr,DTA_RenderStyle,(1|2<<8|1<<16));
 			}
 		}
-		// other stuff
-		Screen.DrawTexture(reticle,false,320,240,DTA_VirtualWidth,640,DTA_VirtualHeight,480,DTA_RenderStyle,(1|2<<8|1<<16));
+		// reticle
+		Vector2 vs = (640,640/Screen.GetAspectRatio());
+		Vector2 mid, siz;
+		[mid, siz] = Screen.VirtualToRealCoords(vs*0.5,(128,128),vs,false,false);
+		Vector2 verts[4];
+		verts[0] = (-siz.x,-siz.y);
+		verts[1] = (siz.x,-siz.y);
+		verts[2] = (-siz.x,siz.y);
+		verts[3] = (siz.x,siz.y);
+		rreticle.Clear(Shape2D.C_Verts);
+		for ( int i=0; i<4; i++ )
+			rreticle.PushVertex(mid+(verts[i].x*cos(LagRoll2)-verts[i].y*sin(LagRoll2),verts[i].x*sin(LagRoll2)+verts[i].y*cos(LagRoll2)));
+		Screen.DrawShape(reticle1,false,rreticle,DTA_RenderStyle,(1|2<<8|1<<16));
+		Screen.DrawTexture(reticle2,false,vs.x*0.5,vs.y*0.5,DTA_VirtualWidthF,vs.x,DTA_VirtualHeightF,vs.y,DTA_KeepRatio,true,DTA_RenderStyle,(1|2<<8|1<<16));
+		// faux assembly readout
 		int numreadouts = Screen.GetHeight()/128+2;
 		for ( int i=0; i<numreadouts; i++ )
 		{