Step 22-A implement session
Change-Id: Ida63382ffb756e20cc5b17c2702d2895e7e6e889
diff --git a/native/jni/src/geometry_utils.h b/native/jni/src/geometry_utils.h
new file mode 100644
index 0000000..ada889e
--- /dev/null
+++ b/native/jni/src/geometry_utils.h
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+/*
+ * Copyright (C) 2012 The Android Open Source Project
+ *
+ * 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 LATINIME_INCREMENTAL_GEOMETRY_UTILS_H
+#define LATINIME_INCREMENTAL_GEOMETRY_UTILS_H
+
+#include <cmath>
+
+#define MAX_DISTANCE 10000000
+#define KEY_NUM 27
+#define SPACE_KEY 26
+#define MAX_PATHS 2
+
+#define DEBUG_DECODER false
+
+namespace latinime {
+
+static inline float sqr(float x) {
+ return x * x;
+}
+
+static inline float getNormalizedSqrDistance(int x1, int y1, int x2, int y2, int scale) {
+ return sqr((x1 - x2) * 1.0 / scale) + sqr((y1 - y2) * 1.0 / scale);
+}
+
+static inline int getDistance(int x1, int y1, int x2, int y2) {
+ return (int) sqrt(sqr(x2 - x1) + sqr(y2 - y1));
+}
+
+static inline float getDistanceSq(float x1, float y1, float x2, float y2) {
+ return sqr(x2 - x1) + sqr(y2 - y1);
+}
+
+static inline float getAngle(int x1, int y1, int x2, int y2) {
+ float dx = x1 - x2;
+ float dy = y1 - y2;
+ if (dx == 0 && dy == 0)
+ return 0;
+ return atan2(dy, dx);
+}
+
+static inline float angleDiff(float a1, float a2) {
+ float diff = a1 - a2;
+ if (diff < 0) {
+ diff = -diff;
+ }
+ if (diff > M_PI) {
+ return 2 * M_PI - diff;
+ }
+ return diff;
+}
+
+//static float pointToLineDistanceSq(float x, float y, float x1, float y1, float x2, float y2) {
+// float A = x - x1;
+// float B = y - y1;
+// float C = x2 - x1;
+// float D = y2 - y1;
+// return abs(A * D - C * B) / sqrt(C * C + D * D);
+//}
+
+static inline float pointToLineSegDistanceSq(
+ float x, float y, float x1, float y1, float x2, float y2) {
+ float ray1x = x - x1;
+ float ray1y = y - y1;
+ float ray2x = x2 - x1;
+ float ray2y = y2 - y1;
+
+ float dotProduct = ray1x * ray2x + ray1y * ray2y;
+ float lineLengthSq = ray2x * ray2x + ray2y * ray2y;
+ float projectionLengthSq = dotProduct / lineLengthSq;
+
+ float projectionX, projectionY;
+ if (projectionLengthSq < 0) {
+ projectionX = x1;
+ projectionY = y1;
+ } else if (projectionLengthSq > 1) {
+ projectionX = x2;
+ projectionY = y2;
+ } else {
+ projectionX = x1 + projectionLengthSq * ray2x;
+ projectionY = y1 + projectionLengthSq * ray2y;
+ }
+
+ float dist = getDistanceSq(x, y, projectionX, projectionY);
+ return dist;
+}
+} // namespace latinime
+#endif // LATINIME_INCREMENTAL_GEOMETRY_UTILS_H