Add grail_contact and a method to retrieve the current contacts

This patch adds the possibility to extract the current set of
contacts from the grail state.

Signed-off-by: Henrik Rydberg <rydberg@euromail.se>

4 files changed, 101 insertions, 1 deletions

diff --git a/include/grail.h b/include/grail.h
index ae3a73f..40cf22f 100644
--- a/include/grail.h
+++ b/include/grail.h
@@ -49,6 +49,32 @@ struct grail_coord {
         float x, y;
 };
 
+/**
+ * struct grail_contact - MT event information in bounding box units
+ * @id: Contact tracking id
+ * @tool_type: Tool type (ABS_MT_TOOL_TYPE)
+ * @pos: Position of contact (bbox units)
+ * @touch_major: Major axis of contact shape (bbox units)
+ * @touch_minor: Minor axis of contact shape (bbox units)
+ * @width_major: Major axis of perimeter (bbox units)
+ * @width_minor: Minor axis of perimeter (bbox units)
+ * @angle: Angle of orientation (vertical: 0 horizontal: +-M_PI_2)
+ * @pressure: Pressure of contact (min: 0 max: 1)
+ *
+ * Depending on the native support of the underlying device, some or all of
+ * the listed properties may be computed.
+ */
+struct grail_contact {
+        int id;
+        int tool_type;
+        struct grail_coord pos;
+        float touch_major;
+        float touch_minor;
+        float width_major;
+        float width_minor;
+        float angle;
+        float pressure;
+};
 
 /**
  * struct grail_client_id - Gesture client information
@@ -228,4 +254,16 @@ void grail_filter_abs_events(struct grail *ge, int usage);
 void grail_get_units(const struct grail *ge,
                      struct grail_coord *min, struct grail_coord *max);
 
+/**
+ * grail_get_contacts - get current contact state
+ * @ge: the grail device in use
+ * @touch: array of contacts to be filled in
+ * @max_touch: maximum number of contacts supported by the array
+ *
+ * Extract the contact state as currently seen by grail.
+ *
+ */
+int grail_get_contacts(const struct grail *ge,
+                       struct grail_contact *touch, int max_touch);
+
 #endif
diff --git a/src/Makefile.am b/src/Makefile.am
index eec0eeb..06a33fa 100644
--- a/src/Makefile.am
+++ b/src/Makefile.am
@@ -21,6 +21,7 @@ libutouch_grail_la_SOURCES = \
         gestures-tapping.c \
         grail-recognizer.c \
         grail-recognizer.h \
+        grail-event.c \
         grail-api.c
 
 AM_CFLAGS = $(CWARNFLAGS)
diff --git a/src/grail-event.c b/src/grail-event.c
new file mode 100644
index 0000000..6479cc0
--- /dev/null
+++ b/src/grail-event.c
@@ -0,0 +1,51 @@
+/*****************************************************************************
+ *
+ * grail - Gesture Recognition And Instantiation Library
+ *
+ * Copyright (C) 2010 Canonical Ltd.
+ * Copyright (C) 2010 Henrik Rydberg <rydberg@bitmath.org>
+ *
+ * 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/>.
+ *
+ ****************************************************************************/
+
+#include "grail-inserter.h"
+#include "grail-impl.h"
+#include <math.h>
+
+int grail_get_contacts(const struct grail *ge,
+                       struct grail_contact *touch, int max_touch)
+{
+        const struct touch_dev *dev = &ge->impl->dev;
+        const struct gesture_inserter *gin = ge->gin;
+        const struct touch_frame *frame = &dev->frame;
+        int i;
+        if (frame->nactive < max_touch)
+                max_touch = frame->nactive;
+        for (i = 0; i < max_touch; i++) {
+                struct grail_contact *t = &touch[i];
+                const struct touch *ct = frame->active[i];
+                t->id = ct->id;
+                t->tool_type = ct->tool_type;
+                t->pos.x = gin_prop_x(gin, ct->x);
+                t->pos.y = gin_prop_y(gin, ct->y);
+                t->touch_major = gin->scale_r * ct->touch_major;
+                t->touch_minor = gin->scale_r * ct->touch_minor;
+                t->width_major = gin->scale_r * ct->width_major;
+                t->width_minor = gin->scale_r * ct->width_minor;
+                t->angle = touch_angle(dev, ct->orientation);
+                t->pressure = touch_pressure(dev, ct->pressure);
+        }
+        return max_touch;
+}
diff --git a/test/grail-gesture.c b/test/grail-gesture.c
index 762d3df..d30e713 100644
--- a/test/grail-gesture.c
+++ b/test/grail-gesture.c
@@ -53,11 +53,21 @@ static void tp_event(struct grail *ge, const struct input_event *ev)
 
 static void tp_gesture(struct grail *ge, const struct grail_event *ev)
 {
-        int i;
+        struct grail_contact touch[32];
+        int i, ntouch;
         fprintf(stderr, "gesture %d %d %d %d - %f %f %d - %d\n",
                 ev->type, ev->id, ev->client_id.client, ev->client_id.event,
                 ev->pos.x, ev->pos.y, ev->ntouch,
                 ev->status);
+        ntouch = grail_get_contacts(ge, touch, 32);
+        for (i = 0; i < ntouch; i++) {
+                const struct grail_contact *t = &touch[i];
+                fprintf(stderr, "\t%d: %d %d\n", i, t->id, t->tool_type);
+                fprintf(stderr, "\t   %f %f\n", t->pos.x, t->pos.y);
+                fprintf(stderr, "\t   %f %f %f %f\n", t->touch_major,
+                        t->touch_minor, t->width_major, t->width_minor);
+                fprintf(stderr, "\t   %f %f\n", t->angle, t->pressure);
+        }
         for (i = 0; i < ev->nprop; i++)
                 fprintf(stderr, "\t%d: %f\n", i, ev->prop[i]);
 }