Add recentering

Signed-off-by: Slendi <slendi@socopon.com>

src/Config.c

@@ -159,7 +159,6 @@ int config_load_ref(lua_State *L, int idx, Config *out)
 
 	// ======== DEFAULTS ========
 	out->space.offset = (Vector3) { 0, 0, 0 };
-	out->space.initial_center = (Vector3) { 0, 0, 0 };
 	out->space.radius = 1.0f;
 	out->space.window_scale = 0.001f;
 	out->displays.hud.size = 720;
@@ -262,11 +261,6 @@ int config_load_ref(lua_State *L, int idx, Config *out)
 			out->space.offset = lua_readVector3(L, lua_absindex(L, -1));
 		lua_pop(L, 1);
 
-		lua_getfield(L, -1, "initial_center");
-		if (lua_istable(L, -1) || lua_isuserdata(L, -1))
-			out->space.initial_center = lua_readVector3(L, lua_absindex(L, -1));
-		lua_pop(L, 1);
-
 		lua_getfield(L, -1, "radius");
 		if (lua_isnumber(L, -1))
 			out->space.radius = (float)lua_tonumber(L, -1);

src/Config.h

@@ -28,7 +28,6 @@ typedef struct {
 
 	struct {
 		Vector3 offset;
-		Vector3 initial_center;
 		float radius;
 		float window_scale;
 	} space;

src/LunarWM.c

@@ -1638,7 +1638,26 @@ static int l_cycle_next(lua_State *L)
 
 static int l_recenter(lua_State *L)
 {
-	g_wm.renderer.center = g_wm.renderer.camera.position;
+	(void)L;
+
+	Vector3 pos = g_wm.renderer.camera.position;
+	Vector3 fwd
+	    = Vector3Normalize(Vector3Subtract(g_wm.renderer.camera.target, pos));
+
+	float len_xz = sqrtf(fwd.x * fwd.x + fwd.z * fwd.z);
+	float yaw = (len_xz > 1e-6f) ? atan2f(fwd.x, fwd.z) : 0.0f;
+
+	Quaternion q_step = QuaternionFromAxisAngle((Vector3) { 0, 1, 0 }, -yaw);
+	Vector3 t_step = Vector3Negate(Vector3RotateByQuaternion(pos, q_step));
+
+	Quaternion q_total = QuaternionMultiply(q_step, g_wm.xr.recenter_rot);
+	Vector3 t_total = Vector3Add(
+	    Vector3RotateByQuaternion(g_wm.xr.recenter_trans, q_step), t_step);
+
+	g_wm.xr.recenter_rot = q_total;
+	g_wm.xr.recenter_trans = t_total;
+	g_wm.xr.recenter_active = true;
+
 	lua_pushnil(L);
 	return 1;
 }
@@ -1679,7 +1698,9 @@ bool LunarWM_init(LunarWM *this)
 		this->renderer.camera.up = (Vector3) { 0, 1, 0 };
 		this->renderer.camera.fovy = 45;
 		this->renderer.camera.projection = CAMERA_PERSPECTIVE;
-		this->renderer.center = (Vector3) { 0, 0, 0 };
+		this->xr.recenter_rot = (Quaternion) { 0, 0, 0, 1 };
+		this->xr.recenter_trans = (Vector3) { 0, 0, 0 };
+		this->xr.recenter_active = false;
 	}
 
 	this->cman = config_manager_create(get_config_path());
@@ -1702,8 +1723,6 @@ bool LunarWM_init(LunarWM *this)
 		lua_setglobal(L, "lunar");
 
 		config_manager_reload(this->cman);
-
-		this->renderer.center = this->cman->cfg.space.initial_center;
 	}
 
 	if (getenv("DISPLAY") != nullptr || getenv("WAYLAND_DISPLAY") != nullptr) {
@@ -2201,7 +2220,7 @@ void render_hud(LunarWM *this, float /*dt*/, int hud_size)
 
 void render_3d(LunarWM *this, float /*dt*/)
 {
-	Skybox_draw(this->renderer.skybox, this->renderer.center);
+	Skybox_draw(this->renderer.skybox, Vector3Zero());
 
 	// rlDisableBackfaceCulling();
 	for (size_t i = 0; i < vector_size(this->wayland.v_toplevels); i++) {
@@ -2214,10 +2233,8 @@ void render_3d(LunarWM *this, float /*dt*/)
 		//	continue;
 
 		DrawTexture3D(tl->rl_texture,
-		    Vector3Add(this->renderer.center,
-		        (Vector3) {
-		            0, 0, this->cman->cfg.space.radius - 0.01 * (float)i }),
-		    this->renderer.center, this->cman->cfg.space.window_scale, false);
+		    (Vector3) { 0, 0, this->cman->cfg.space.radius - 0.01 * (float)i },
+		    Vector3Zero(), this->cman->cfg.space.window_scale, false);
 	}
 	// rlEnableBackfaceCulling();
 
@@ -2257,6 +2274,21 @@ void render_3d(LunarWM *this, float /*dt*/)
 	}
 }
 
+static inline Vector3 RecenterPoint(LunarWM *wm, Vector3 p)
+{
+	if (!wm->xr.recenter_active)
+		return p;
+	return Vector3Add(Vector3RotateByQuaternion(p, wm->xr.recenter_rot),
+	    wm->xr.recenter_trans);
+}
+
+static inline Quaternion RecenterOrient(LunarWM *wm, Quaternion q)
+{
+	if (!wm->xr.recenter_active)
+		return q;
+	return QuaternionMultiply(wm->xr.recenter_rot, q);
+}
+
 static bool render_layer(LunarWM *this, LunarWM_RenderLayerInfo *info, float dt)
 {
 	auto const view_count = (uint32_t)this->xr.view_configuration_views_count;
@@ -2395,6 +2427,23 @@ static bool render_layer(LunarWM *this, LunarWM_RenderLayerInfo *info, float dt)
 			    = Vector3Add(this->renderer.camera.position, forward);
 			this->renderer.camera.up = up;
 		}
+
+		if (this->xr.recenter_active) {
+			Vector3 pos = this->renderer.camera.position;
+			Vector3 fwd = Vector3Normalize(
+			    Vector3Subtract(this->renderer.camera.target, pos));
+			Vector3 up = this->renderer.camera.up;
+
+			pos = Vector3Add(
+			    Vector3RotateByQuaternion(pos, this->xr.recenter_rot),
+			    this->xr.recenter_trans);
+			fwd = Vector3RotateByQuaternion(fwd, this->xr.recenter_rot);
+			up = Vector3RotateByQuaternion(up, this->xr.recenter_rot);
+
+			this->renderer.camera.position = pos;
+			this->renderer.camera.target = Vector3Add(pos, fwd);
+			this->renderer.camera.up = up;
+		}
 	}
 
 	BeginMode3D(this->renderer.camera);
@@ -2592,6 +2641,33 @@ void LunarWM_run(LunarWM *this)
 					return;
 				}
 			}
+
+			for (int h = 0; h < 2; h++) {
+				auto *hand_info = &this->xr.hands[h];
+				for (size_t k = 0; k < XR_HAND_JOINT_COUNT_EXT; ++k) {
+					auto *jl = &hand_info->joint_locations[k];
+
+					Vector3 pos = { jl->pose.position.x, jl->pose.position.y,
+						jl->pose.position.z };
+					pos = RecenterPoint(this, pos);
+
+					Quaternion q
+					    = { jl->pose.orientation.x, jl->pose.orientation.y,
+						      jl->pose.orientation.z, jl->pose.orientation.w };
+					q = RecenterOrient(this, q);
+
+					jl->pose.position.x = pos.x;
+					jl->pose.position.y = pos.y;
+					jl->pose.position.z = pos.z;
+
+					jl->pose.orientation.x = q.x;
+					jl->pose.orientation.y = q.y;
+					jl->pose.orientation.z = q.z;
+					jl->pose.orientation.w = q.w;
+
+					DrawSphere(pos, jl->radius, (Color) { 255, 0, 0, 255 });
+				}
+			}
 		}
 
 		LunarWM_RenderLayerInfo render_layer_info = {

src/LunarWM.h

@@ -190,6 +190,10 @@ typedef struct LunarWM {
 		PFN_xrDestroyHandTrackerEXT DestroyHandTrackerEXT;
 		PFN_xrLocateHandJointsEXT LocateHandJointsEXT;
 
+		Quaternion recenter_rot;
+		Vector3 recenter_trans;
+		bool recenter_active;
+
 		bool session_running;
 	} xr;
 
@@ -201,8 +205,6 @@ typedef struct LunarWM {
 		Camera3D camera;
 		Shader linear_srgb;
 
-		Vector3 center;
-
 		Skybox skybox;
 	} renderer;