commit 816c832c449c506e73761af5d9b807b80eb26954
author Amirhossein Simjour <asimjour@chromium.org> Wed Apr 08 15:43:48 2015 -0400
committer ChromeOS Commit Bot <chromeos-commit-bot@chromium.org> Tue Apr 14 01:15:38 2015 +0000
tree 77f710e1f457d1c9e5ac9a967ee0cbbe6d947929
parent 2af67890317a3371ed213a3cda4f5e4ae95f2a74

Scaling filter is changed to stop filtering small fingers

The threshold is modified to allow small fingers.
Fingers with pressure smaller than one are converted to fingers
with pressure = 1.0

BUG=chromium:475186
TEST=Manually tested and fixes the reported log. Regression test is
performed and no new problem was introduced.
All unittests pass.

Change-Id: I321c31536ea2043369810c33bd0cc8baee54cd5a
Reviewed-on: https://chromium-review.googlesource.com/264783
Reviewed-by: Andrew de los Reyes <adlr@chromium.org>
Tested-by: Amirhossein Simjour <asimjour@chromium.org>
Commit-Queue: Amirhossein Simjour <asimjour@chromium.org>

include/scaling_filter_interpreter.h

diff --git a/include/scaling_filter_interpreter.h b/include/scaling_filter_interpreter.h
index 2d78749..28d1346 100644
--- a/include/scaling_filter_interpreter.h
+++ b/include/scaling_filter_interpreter.h
@@ -100,6 +100,10 @@
   DoubleProperty pressure_scale_;
   DoubleProperty pressure_translate_;
   DoubleProperty pressure_threshold_;
+  // if true, the low pressure touch will be ignored.
+  // if false, or doesn't exist, the low pressure touch will be converted
+  // to touch with pressure 1.0
+  BoolProperty filter_low_pressure_;
 
   // If true, adjust touch count to match finger count when scaling
   // input state. This can help avoid being considered a T5R2 pad.

src/scaling_filter_interpreter.cc

diff --git a/src/scaling_filter_interpreter.cc b/src/scaling_filter_interpreter.cc
index 0578d6c..9f9219c 100644
--- a/src/scaling_filter_interpreter.cc
+++ b/src/scaling_filter_interpreter.cc
@@ -33,6 +33,7 @@
       pressure_scale_(prop_reg, "Pressure Calibration Slope", 1.0),
       pressure_translate_(prop_reg, "Pressure Calibration Offset", 0.0),
       pressure_threshold_(prop_reg, "Pressure Minimum Threshold", 0.0),
+      filter_low_pressure_(prop_reg, "Filter Low Pressure", 0),
       force_touch_count_to_match_finger_count_(
           prop_reg,
           "Force Touch Count To Match Finger Count",
@@ -129,7 +130,8 @@
 
   if (surface_area_from_pressure_.val_) {
     // Drop the small fingers, i.e. low pressures.
-    FilterLowPressure(hwstate);
+    if (filter_low_pressure_.val_ || pressure_threshold_.val_ > 0.0)
+      FilterLowPressure(hwstate);
   }
 
   for (short i = 0; i < hwstate->finger_cnt; i++) {
@@ -191,6 +193,9 @@
       else
         hwstate->fingers[i].pressure = 0;
     }
+
+    hwstate->fingers[i].pressure = std::max(1.0f,
+                                            hwstate->fingers[i].pressure);
   }
 
   if (!surface_area_from_pressure_.val_) {

src/scaling_filter_interpreter_unittest.cc

diff --git a/src/scaling_filter_interpreter_unittest.cc b/src/scaling_filter_interpreter_unittest.cc
index b43b4b1..7d3ba5a 100644
--- a/src/scaling_filter_interpreter_unittest.cc
+++ b/src/scaling_filter_interpreter_unittest.cc
@@ -323,6 +323,8 @@
 
     has_zero_area[i] = pressure == 0.0;
 
+    pressure = std::max(pressure , 1.0f);
+
     if (has_zero_area[i]) {
       base_interpreter->expected_orientation_.push_back(
           std::vector<float>(0));
@@ -374,7 +376,10 @@
 
   const float e_x = 17;
   const float e_y = 71;
+  const bool kFilterLowPressure = 1;
+
   interpreter.surface_area_from_pressure_.val_ = false;
+  interpreter.filter_low_pressure_.val_ = kFilterLowPressure;
   interpreter.tp_x_bias_.val_ = e_x;
   interpreter.tp_y_bias_.val_ = e_y;