Make blend animation to use ResetTrack as default value

core/extension/gdnative_interface.cpp

@@ -241,6 +241,13 @@ static GDNativeBool gdnative_variant_booleanize(const GDNativeVariantPtr p_self)
 	return self->booleanize();
 }
 
+static void gdnative_variant_sub(const GDNativeVariantPtr p_a, const GDNativeVariantPtr p_b, GDNativeVariantPtr r_dst) {
+	const Variant *a = (const Variant *)p_a;
+	const Variant *b = (const Variant *)p_b;
+	memnew_placement(r_dst, Variant);
+	Variant::sub(*a, *b, *(Variant *)r_dst);
+}
+
 static void gdnative_variant_blend(const GDNativeVariantPtr p_a, const GDNativeVariantPtr p_b, float p_c, GDNativeVariantPtr r_dst) {
 	const Variant *a = (const Variant *)p_a;
 	const Variant *b = (const Variant *)p_b;
@@ -939,6 +946,7 @@ void gdnative_setup_interface(GDNativeInterface *p_interface) {
 	gdni.variant_iter_get = gdnative_variant_iter_get;
 	gdni.variant_hash_compare = gdnative_variant_hash_compare;
 	gdni.variant_booleanize = gdnative_variant_booleanize;
+	gdni.variant_sub = gdnative_variant_sub;
 	gdni.variant_blend = gdnative_variant_blend;
 	gdni.variant_interpolate = gdnative_variant_interpolate;
 	gdni.variant_duplicate = gdnative_variant_duplicate;

core/extension/gdnative_interface.h

@@ -416,6 +416,7 @@ typedef struct {
 	void (*variant_iter_get)(const GDNativeVariantPtr p_self, GDNativeVariantPtr r_iter, GDNativeVariantPtr r_ret, GDNativeBool *r_valid);
 	GDNativeBool (*variant_hash_compare)(const GDNativeVariantPtr p_self, const GDNativeVariantPtr p_other);
 	GDNativeBool (*variant_booleanize)(const GDNativeVariantPtr p_self);
+	void (*variant_sub)(const GDNativeVariantPtr p_a, const GDNativeVariantPtr p_b, GDNativeVariantPtr r_dst);
 	void (*variant_blend)(const GDNativeVariantPtr p_a, const GDNativeVariantPtr p_b, float p_c, GDNativeVariantPtr r_dst);
 	void (*variant_interpolate)(const GDNativeVariantPtr p_a, const GDNativeVariantPtr p_b, float p_c, GDNativeVariantPtr r_dst);
 	void (*variant_duplicate)(const GDNativeVariantPtr p_self, GDNativeVariantPtr r_ret, GDNativeBool p_deep);

core/variant/variant.h

@@ -511,6 +511,7 @@ public:
 	Variant recursive_duplicate(bool p_deep, int recursion_count) const;
 	static void blend(const Variant &a, const Variant &b, float c, Variant &r_dst);
 	static void interpolate(const Variant &a, const Variant &b, float c, Variant &r_dst);
+	static void sub(const Variant &a, const Variant &b, Variant &r_dst);
 
 	/* Built-In Methods */
 

core/variant/variant_setget.cpp

@@ -1868,6 +1868,110 @@ Variant Variant::recursive_duplicate(bool p_deep, int recursion_count) const {
 	}
 }
 
+void Variant::sub(const Variant &a, const Variant &b, Variant &r_dst) {
+	if (a.type != b.type) {
+		return;
+	}
+
+	switch (a.type) {
+		case NIL: {
+			r_dst = Variant();
+		}
+			return;
+		case INT: {
+			int64_t va = a._data._int;
+			int64_t vb = b._data._int;
+			r_dst = int(va - vb);
+		}
+			return;
+		case FLOAT: {
+			double ra = a._data._float;
+			double rb = b._data._float;
+			r_dst = ra - rb;
+		}
+			return;
+		case VECTOR2: {
+			r_dst = *reinterpret_cast<const Vector2 *>(a._data._mem) - *reinterpret_cast<const Vector2 *>(b._data._mem);
+		}
+			return;
+		case VECTOR2I: {
+			int32_t vax = reinterpret_cast<const Vector2i *>(a._data._mem)->x;
+			int32_t vbx = reinterpret_cast<const Vector2i *>(b._data._mem)->x;
+			int32_t vay = reinterpret_cast<const Vector2i *>(a._data._mem)->y;
+			int32_t vby = reinterpret_cast<const Vector2i *>(b._data._mem)->y;
+			r_dst = Vector2i(int32_t(vax - vbx), int32_t(vay - vby));
+		}
+			return;
+		case RECT2: {
+			const Rect2 *ra = reinterpret_cast<const Rect2 *>(a._data._mem);
+			const Rect2 *rb = reinterpret_cast<const Rect2 *>(b._data._mem);
+			r_dst = Rect2(ra->position - rb->position, ra->size - rb->size);
+		}
+			return;
+		case RECT2I: {
+			const Rect2i *ra = reinterpret_cast<const Rect2i *>(a._data._mem);
+			const Rect2i *rb = reinterpret_cast<const Rect2i *>(b._data._mem);
+
+			int32_t vax = ra->position.x;
+			int32_t vay = ra->position.y;
+			int32_t vbx = ra->size.x;
+			int32_t vby = ra->size.y;
+			int32_t vcx = rb->position.x;
+			int32_t vcy = rb->position.y;
+			int32_t vdx = rb->size.x;
+			int32_t vdy = rb->size.y;
+
+			r_dst = Rect2i(int32_t(vax - vbx), int32_t(vay - vby), int32_t(vcx - vdx), int32_t(vcy - vdy));
+		}
+			return;
+		case VECTOR3: {
+			r_dst = *reinterpret_cast<const Vector3 *>(a._data._mem) - *reinterpret_cast<const Vector3 *>(b._data._mem);
+		}
+			return;
+		case VECTOR3I: {
+			int32_t vax = reinterpret_cast<const Vector3i *>(a._data._mem)->x;
+			int32_t vbx = reinterpret_cast<const Vector3i *>(b._data._mem)->x;
+			int32_t vay = reinterpret_cast<const Vector3i *>(a._data._mem)->y;
+			int32_t vby = reinterpret_cast<const Vector3i *>(b._data._mem)->y;
+			int32_t vaz = reinterpret_cast<const Vector3i *>(a._data._mem)->z;
+			int32_t vbz = reinterpret_cast<const Vector3i *>(b._data._mem)->z;
+			r_dst = Vector3i(int32_t(vax - vbx), int32_t(vay - vby), int32_t(vaz - vbz));
+		}
+			return;
+		case AABB: {
+			const ::AABB *ra = reinterpret_cast<const ::AABB *>(a._data._mem);
+			const ::AABB *rb = reinterpret_cast<const ::AABB *>(b._data._mem);
+			r_dst = ::AABB(ra->position - rb->position, ra->size - rb->size);
+		}
+			return;
+		case QUATERNION: {
+			Quaternion empty_rot;
+			const Quaternion *qa = reinterpret_cast<const Quaternion *>(a._data._mem);
+			const Quaternion *qb = reinterpret_cast<const Quaternion *>(b._data._mem);
+			r_dst = (*qb).inverse() * *qa;
+		}
+			return;
+		case COLOR: {
+			const Color *ca = reinterpret_cast<const Color *>(a._data._mem);
+			const Color *cb = reinterpret_cast<const Color *>(b._data._mem);
+			float new_r = ca->r - cb->r;
+			float new_g = ca->g - cb->g;
+			float new_b = ca->b - cb->b;
+			float new_a = ca->a - cb->a;
+			new_r = new_r > 1.0 ? 1.0 : new_r;
+			new_g = new_g > 1.0 ? 1.0 : new_g;
+			new_b = new_b > 1.0 ? 1.0 : new_b;
+			new_a = new_a > 1.0 ? 1.0 : new_a;
+			r_dst = Color(new_r, new_g, new_b, new_a);
+		}
+			return;
+		default: {
+			r_dst = a;
+		}
+			return;
+	}
+}
+
 void Variant::blend(const Variant &a, const Variant &b, float c, Variant &r_dst) {
 	if (a.type != b.type) {
 		if (a.is_num() && b.is_num()) {

scene/animation/animation_tree.cpp

@@ -540,6 +540,11 @@ bool AnimationTree::_update_caches(AnimationPlayer *player) {
 	List<StringName> sname;
 	player->get_animation_list(&sname);
 
+	Ref<Animation> reset_anim;
+	bool has_reset_anim = player->has_animation("RESET");
+	if (has_reset_anim) {
+		reset_anim = player->get_animation("RESET");
+	}
 	for (const StringName &E : sname) {
 		Ref<Animation> anim = player->get_animation(E);
 		for (int i = 0; i < anim->get_track_count(); i++) {
@@ -593,6 +598,12 @@ bool AnimationTree::_update_caches(AnimationPlayer *player) {
 
 						track = track_value;
 
+						if (has_reset_anim) {
+							int rt = reset_anim->find_track(path, track_type);
+							if (rt >= 0 && reset_anim->track_get_key_count(rt) > 0) {
+								track_value->init_value = reset_anim->track_get_key_value(rt, 0);
+							}
+						}
 					} break;
 					case Animation::TYPE_POSITION_3D:
 					case Animation::TYPE_ROTATION_3D:
@@ -645,6 +656,25 @@ bool AnimationTree::_update_caches(AnimationPlayer *player) {
 							}
 						}
 
+						if (has_reset_anim) {
+							int rt = reset_anim->find_track(path, track_type);
+							if (rt >= 0 && reset_anim->track_get_key_count(rt) > 0) {
+								switch (track_type) {
+									case Animation::TYPE_POSITION_3D: {
+										track_xform->init_loc = reset_anim->track_get_key_value(rt, 0);
+									} break;
+									case Animation::TYPE_ROTATION_3D: {
+										track_xform->ref_rot = reset_anim->track_get_key_value(rt, 0);
+										track_xform->init_rot = track_xform->ref_rot.log();
+									} break;
+									case Animation::TYPE_SCALE_3D: {
+										track_xform->init_scale = reset_anim->track_get_key_value(rt, 0);
+									} break;
+									default: {
+									}
+								}
+							}
+						}
 #endif // _3D_DISABLED
 					} break;
 					case Animation::TYPE_BLEND_SHAPE: {
@@ -675,6 +705,13 @@ bool AnimationTree::_update_caches(AnimationPlayer *player) {
 						track_bshape->object = mesh_3d;
 						track_bshape->object_id = mesh_3d->get_instance_id();
 						track = track_bshape;
+
+						if (has_reset_anim) {
+							int rt = reset_anim->find_track(path, track_type);
+							if (rt >= 0 && reset_anim->track_get_key_count(rt) > 0) {
+								track_bshape->init_value = reset_anim->track_get_key_value(rt, 0);
+							}
+						}
 #endif
 					} break;
 					case Animation::TYPE_METHOD: {
@@ -704,6 +741,13 @@ bool AnimationTree::_update_caches(AnimationPlayer *player) {
 						track_bezier->object_id = track_bezier->object->get_instance_id();
 
 						track = track_bezier;
+
+						if (has_reset_anim) {
+							int rt = reset_anim->find_track(path, track_type);
+							if (rt >= 0 && reset_anim->track_get_key_count(rt) > 0) {
+								track_bezier->init_value = reset_anim->track_get_key_value(rt, 0);
+							}
+						}
 					} break;
 					case Animation::TYPE_AUDIO: {
 						TrackCacheAudio *track_audio = memnew(TrackCacheAudio);
@@ -1226,7 +1270,7 @@ void AnimationTree::_process_graph(double p_delta) {
 
 						if (t->process_pass != process_pass) {
 							t->process_pass = process_pass;
-							t->value = 0;
+							t->value = t->init_value;
 						}
 
 						float value;
@@ -1238,7 +1282,7 @@ void AnimationTree::_process_graph(double p_delta) {
 							continue;
 						}
 
-						t->value += value * blend;
+						t->value += (value - t->init_value) * blend;
 #endif // _3D_DISABLED
 					} break;
 					case Animation::TYPE_VALUE: {
@@ -1256,10 +1300,15 @@ void AnimationTree::_process_graph(double p_delta) {
 
 							if (t->process_pass != process_pass) {
 								t->process_pass = process_pass;
-								t->value = value;
+								if (!t->init_value) {
-								t->value.zero();
+									t->init_value = value;
+									t->init_value.zero();
+								} else {
+									t->value = t->init_value;
+								}
 							}
 
+							Variant::sub(value, t->init_value, value);
 							Variant::blend(t->value, value, blend, t->value);
 						} else {
 							if (blend < CMP_EPSILON) {
@@ -1303,10 +1352,10 @@ void AnimationTree::_process_graph(double p_delta) {
 
 						if (t->process_pass != process_pass) {
 							t->process_pass = process_pass;
-							t->value = 0;
+							t->value = t->init_value;
 						}
 
-						t->value += bezier * blend;
+						t->value += (bezier - t->init_value) * blend;
 					} break;
 					case Animation::TYPE_AUDIO: {
 						if (blend < CMP_EPSILON) {

scene/animation/animation_tree.h

@@ -212,12 +212,14 @@ private:
 
 	struct TrackCacheBlendShape : public TrackCache {
 		MeshInstance3D *mesh_3d = nullptr;
+		float init_value = 0;
 		float value = 0;
 		int shape_index = -1;
 		TrackCacheBlendShape() { type = Animation::TYPE_BLEND_SHAPE; }
 	};
 
 	struct TrackCacheValue : public TrackCache {
+		Variant init_value;
 		Variant value;
 		Vector<StringName> subpath;
 		TrackCacheValue() { type = Animation::TYPE_VALUE; }
@@ -228,6 +230,7 @@ private:
 	};
 
 	struct TrackCacheBezier : public TrackCache {
+		real_t init_value = 0.0;
 		real_t value = 0.0;
 		Vector<StringName> subpath;
 		TrackCacheBezier() {