Revert "Drop circular pad support"

This reverts commit 3b02e7fd81da4b100fb9ac32378f6d50f54cf0e2.

Signed-off-by: Peter Hutterer <peter.hutterer@who-t.net>

Conflicts:
	man/synaptics.man
	src/synaptics.c

Acked-by: Daniel Stone <daniel@fooishbar.org>
(cherry picked from commit 4f543ce1d6ae9ca11086a3009d149505590584a8)

3 files changed, 65 insertions, 0 deletions

diff --git a/src/properties.c b/src/properties.c
index 0041544..886d8c2 100644
--- a/src/properties.c
+++ b/src/properties.c
@@ -295,6 +295,9 @@ InitDeviceProperties(InputInfoPtr pInfo)
     prop_circscroll_trigger =
         InitAtom(pInfo->dev, SYNAPTICS_PROP_CIRCULAR_SCROLLING_TRIGGER, 8, 1,
                  &para->circular_trigger);
+    prop_circpad =
+        InitAtom(pInfo->dev, SYNAPTICS_PROP_CIRCULAR_PAD, 8, 1,
+                 &para->circular_pad);
     prop_palm =
         InitAtom(pInfo->dev, SYNAPTICS_PROP_PALM_DETECT, 8, 1,
                  &para->palm_detect);
@@ -666,6 +669,12 @@ SetProperty(DeviceIntPtr dev, Atom property, XIPropertyValuePtr prop,
         para->circular_trigger = trigger;
 
     }
+    else if (property == prop_circpad) {
+        if (prop->size != 1 || prop->format != 8 || prop->type != XA_INTEGER)
+            return BadMatch;
+
+        para->circular_pad = *(BOOL *) prop->data;
+    }
     else if (property == prop_palm) {
         if (prop->size != 1 || prop->format != 8 || prop->type != XA_INTEGER)
             return BadMatch;
diff --git a/src/synaptics.c b/src/synaptics.c
index 493986d..1c22873 100644
--- a/src/synaptics.c
+++ b/src/synaptics.c
@@ -701,6 +701,7 @@ set_default_parameters(InputInfoPtr pInfo)
     pars->circular_scrolling =
         xf86SetBoolOption(opts, "CircularScrolling", FALSE);
     pars->circular_trigger = xf86SetIntOption(opts, "CircScrollTrigger", 0);
+    pars->circular_pad = xf86SetBoolOption(opts, "CircularPad", FALSE);
     pars->palm_detect = xf86SetBoolOption(opts, "PalmDetect", FALSE);
     pars->palm_min_width = xf86SetIntOption(opts, "PalmMinWidth", palmMinWidth);
     pars->palm_min_z = xf86SetIntOption(opts, "PalmMinZ", palmMinZ);
@@ -1328,6 +1329,32 @@ DeviceInit(DeviceIntPtr dev)
     return !Success;
 }
 
+/*
+ * Convert from absolute X/Y coordinates to a coordinate system where
+ * -1 corresponds to the left/upper edge and +1 corresponds to the
+ * right/lower edge.
+ */
+static void
+relative_coords(SynapticsPrivate * priv, int x, int y,
+                double *relX, double *relY)
+{
+    int minX = priv->synpara.left_edge;
+    int maxX = priv->synpara.right_edge;
+    int minY = priv->synpara.top_edge;
+    int maxY = priv->synpara.bottom_edge;
+    double xCenter = (minX + maxX) / 2.0;
+    double yCenter = (minY + maxY) / 2.0;
+
+    if ((maxX - xCenter > 0) && (maxY - yCenter > 0)) {
+        *relX = (x - xCenter) / (maxX - xCenter);
+        *relY = (y - yCenter) / (maxY - yCenter);
+    }
+    else {
+        *relX = 0;
+        *relY = 0;
+    }
+}
+
 /* return angle of point relative to center */
 static double
 angle(SynapticsPrivate * priv, int x, int y)
@@ -1352,10 +1379,38 @@ diffa(double a1, double a2)
 }
 
 static enum EdgeType
+circular_edge_detection(SynapticsPrivate * priv, int x, int y)
+{
+    enum EdgeType edge = 0;
+    double relX, relY, relR;
+
+    relative_coords(priv, x, y, &relX, &relY);
+    relR = SQR(relX) + SQR(relY);
+
+    if (relR > 1) {
+        /* we are outside the ellipse enclosed by the edge parameters */
+        if (relX > M_SQRT1_2)
+            edge |= RIGHT_EDGE;
+        else if (relX < -M_SQRT1_2)
+            edge |= LEFT_EDGE;
+
+        if (relY < -M_SQRT1_2)
+            edge |= TOP_EDGE;
+        else if (relY > M_SQRT1_2)
+            edge |= BOTTOM_EDGE;
+    }
+
+    return edge;
+}
+
+static enum EdgeType
 edge_detection(SynapticsPrivate * priv, int x, int y)
 {
     enum EdgeType edge = NO_EDGE;
 
+    if (priv->synpara.circular_pad)
+        return circular_edge_detection(priv, x, y);
+
     if (x > priv->synpara.right_edge)
         edge |= RIGHT_EDGE;
     else if (x < priv->synpara.left_edge)
diff --git a/src/synapticsstr.h b/src/synapticsstr.h
index 3f66b14..54bc154 100644
--- a/src/synapticsstr.h
+++ b/src/synapticsstr.h
@@ -190,6 +190,7 @@ typedef struct _SynapticsParameters {
     Bool circular_scrolling;    /* Enable circular scrolling */
     double scroll_dist_circ;    /* Scrolling angle radians */
     int circular_trigger;       /* Trigger area for circular scrolling */
+    Bool circular_pad;          /* Edge has an oval or circular shape */
     Bool palm_detect;           /* Enable Palm Detection */
     int palm_min_width;         /* Palm detection width */
     int palm_min_z;             /* Palm detection depth */