1 files changed, 74 insertions, 0 deletions

diff --git a/src/gestures-scroll.c b/src/gestures-scroll.c
new file mode 100644
index 0000000..96e153b
--- /dev/null
+++ b/src/gestures-scroll.c
@@ -0,0 +1,74 @@
+/*****************************************************************************
+ *
+ * grail - Gesture Recognition And Instantiation Library
+ *
+ * Copyright (C) 2010 Canonical Ltd.
+ *
+ * This program is free software: you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the
+ * Free Software Foundation, either version 3 of the License, or (at your
+ * option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ * Authors:
+ *      Henrik Rydberg <rydberg@bitmath.org>
+ *
+ ****************************************************************************/
+
+#include "grail-recognizer.h"
+#include <math.h>
+
+void gru_reset_scroll(struct grail *ge,
+                                 const struct touch_frame *frame)
+{
+        struct gesture_inserter *gin = ge->gin;
+        struct gesture_recognizer *gru = ge->gru;
+        struct scroll_model *state = &gru->scroll;
+        struct move_model *move = &gru->move;
+        gin_gesture_discard_type(gin, GRAIL_TYPE_SCROLL);
+        state->x = move->x;
+        state->y = move->y;
+        state->active = 0;
+        state->moving = 0;
+}
+
+int gru_scroll(struct grail *ge,
+                          const struct touch_frame *frame)
+{
+        struct gesture_inserter *gin = ge->gin;
+        struct gesture_recognizer *gru = ge->gru;
+        struct scroll_model *state = &gru->scroll;
+        struct move_model *move = &gru->move;
+        grail_prop_t prop[DIM_GRAIL_PROP];
+        float dx, dy;
+        int i;
+        dx = move->x - state->x;
+        dy = move->y - state->y;
+        if (fabs(dx) < 1 && fabs(dy) < 1)
+                return 0;
+        if (!state->active) {
+                i = gin_gesture_begin(ge, GRAIL_TYPE_SCROLL, 1,
+                                      frame->touches, sizeof(frame->touches));
+                state->geslot = i;
+                state->active = 1;
+        }
+        if (!state->moving && fabs(dx) < move->xbar && fabs(dy) < move->ybar)
+                return 0;
+        state->moving = 1;
+        prop[0] = dx;
+        prop[1] = dy;
+        gin_gesture_event(gin, state->geslot,
+                          move->x, move->y, move->ntouch,
+                          prop, 2);
+        state->x = move->x;
+        state->y = move->y;
+        return 1;
+}
+