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diff --git a/ink_stroke_modeler/stroke_modeler.h b/ink_stroke_modeler/stroke_modeler.h
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+/*
+ * Copyright 2022 Google LLC
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#ifndef INK_STROKE_MODELER_STROKE_MODELER_H_
+#define INK_STROKE_MODELER_STROKE_MODELER_H_
+
+#include <memory>
+#include <vector>
+
+#include "absl/status/status.h"
+#include "absl/status/statusor.h"
+#include "absl/types/optional.h"
+#include "ink_stroke_modeler/internal/position_modeler.h"
+#include "ink_stroke_modeler/internal/prediction/input_predictor.h"
+#include "ink_stroke_modeler/internal/stylus_state_modeler.h"
+#include "ink_stroke_modeler/internal/wobble_smoother.h"
+#include "ink_stroke_modeler/params.h"
+#include "ink_stroke_modeler/types.h"
+
+namespace ink {
+namespace stroke_model {
+
+// This class models a stroke from a raw input stream. The modeling is performed
+// in several stages, which are delegated to component classes:
+// - Wobble Smoothing: Dampens high-frequency noise from quantization error.
+// - Position Modeling: Models the pen tip as a mass, connected by a spring, to
+//   a moving anchor.
+// - Stylus State Modeling: Constructs stylus states for modeled positions by
+//   interpolating over the raw input.
+//
+// Additionally, this class provides prediction of the modeled stroke.
+//
+// StrokeModeler is completely unit-agnostic. That is, it doesn't matter what
+// units or coordinate-system the input is given in; the output will be given in
+// the same coordinate-system and units.
+class StrokeModeler {
+ public:
+  // Clears any in-progress stroke, and initializes (or re-initializes) the
+  // model with the given parameters. Returns an error if the parameters are
+  // invalid.
+  absl::Status Reset(const StrokeModelParams &stroke_model_params);
+
+  // Updates the model with a raw input, returning the generated results. Any
+  // previously generated results are stable, i.e. any previously returned
+  // Results are still valid.
+  //
+  // Returns an error if the the model has not yet been initialized (via Reset)
+  // or if the input stream is malformed (e.g decreasing time, Up event before
+  // Down event).
+  //
+  // If this does not return an error, the result will contain at least one
+  // Result, and potentially more than one if the inputs are slower than
+  // the minimum output rate.
+  absl::StatusOr<std::vector<Result>> Update(const Input &input);
+
+  // Model the given input prediction without changing the internal model state.
+  //
+  // Returns an error if the the model has not yet been initialized (via Reset),
+  // or if there is no stroke in progress. The output is limited to results
+  // where the predictor has sufficient confidence,
+  absl::StatusOr<std::vector<Result>> Predict() const;
+
+ private:
+  absl::StatusOr<std::vector<Result>> ProcessDownEvent(const Input &input);
+  absl::StatusOr<std::vector<Result>> ProcessMoveEvent(const Input &input);
+  absl::StatusOr<std::vector<Result>> ProcessUpEvent(const Input &input);
+
+  std::unique_ptr<InputPredictor> predictor_;
+
+  absl::optional<StrokeModelParams> stroke_model_params_;
+
+  WobbleSmoother wobble_smoother_;
+  PositionModeler position_modeler_;
+  StylusStateModeler stylus_state_modeler_;
+
+  struct InputAndCorrectedPosition {
+    Input input;
+    Vec2 corrected_position{0};
+  };
+  absl::optional<InputAndCorrectedPosition> last_input_;
+};
+
+}  // namespace stroke_model
+}  // namespace ink
+
+#endif  // INK_STROKE_MODELER_STROKE_MODELER_H_