Introduce convenience function for device dimensions

The capability names are rather lengthy; this patch adds convenience
functions for the dimension capabilities.

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

3 files changed, 15 insertions, 6 deletions

diff --git a/src/capabilities.c b/src/capabilities.c
index cdd05c5..7316f01 100644
--- a/src/capabilities.c
+++ b/src/capabilities.c
@@ -81,6 +81,16 @@ int read_capabilities(struct Capabilities *cap, int fd)
         return 0;
 }
 
+int get_cap_xsize(const struct Capabilities *cap)
+{
+        return cap->abs_position_x.maximum - cap->abs_position_x.minimum;
+}
+
+int get_cap_ysize(const struct Capabilities *cap)
+{
+        return cap->abs_position_y.maximum - cap->abs_position_y.minimum;
+}
+
 void output_capabilities(const struct Capabilities *cap)
 {
         char line[1024];
diff --git a/src/capabilities.h b/src/capabilities.h
index 66ce29b..dc257ce 100644
--- a/src/capabilities.h
+++ b/src/capabilities.h
@@ -41,6 +41,9 @@ struct Capabilities {
 };
 
 int read_capabilities(struct Capabilities *cap, int fd);
+int get_cap_xsize(const struct Capabilities *cap);
+int get_cap_ysize(const struct Capabilities *cap);
+
 void output_capabilities(const struct Capabilities *cap);
 
 #endif
diff --git a/src/multitouch.c b/src/multitouch.c
index 2919b9d..fd2393f 100644
--- a/src/multitouch.c
+++ b/src/multitouch.c
@@ -185,12 +185,8 @@ static void handle_gestures(LocalDevicePtr local,
                             const struct Capabilities *caps)
 {
         static int vscroll, hscroll;
-        int vstep = 1 +
-                vscroll_fraction * (caps->abs_position_y.maximum -
-                                    caps->abs_position_y.minimum);
-        int hstep = 1 +
-                hscroll_fraction * (caps->abs_position_x.maximum -
-                                    caps->abs_position_x.minimum);
+        int vstep = 1 + vscroll_fraction * get_cap_ysize(caps);
+        int hstep = 1 + hscroll_fraction * get_cap_xsize(caps);
         int i;
         for (i = 0; i < DIM_BUTTON; i++) {
                 if (GETBIT(gs->btmask, i)) {