Move TouchTransformerController to ui/display/.

ash/touch/touch_transformer_controller.cc

-// Copyright 2014 The Chromium Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style license that can be
-// found in the LICENSE file.
-
-#include "ash/touch/touch_transformer_controller.h"
-
-#include "ash/display/window_tree_host_manager.h"
-#include "ash/host/ash_window_tree_host.h"
-#include "ash/root_window_controller.h"
-#include "ash/shell.h"
-#include "third_party/skia/include/core/SkMatrix44.h"
-#include "ui/aura/window_tree_host.h"
-#include "ui/display/display_layout.h"
-#include "ui/display/manager/chromeos/display_configurator.h"
-#include "ui/display/manager/display_manager.h"
-#include "ui/display/types/display_constants.h"
-#include "ui/display/types/display_snapshot.h"
-#include "ui/events/devices/device_data_manager.h"
-
-namespace ash {
-
-namespace {
-
-display::DisplayManager* GetDisplayManager() {
-  return Shell::GetInstance()->display_manager();
-}
-
-ui::TouchscreenDevice FindTouchscreenById(int id) {
-  const std::vector<ui::TouchscreenDevice>& touchscreens =
-      ui::DeviceDataManager::GetInstance()->GetTouchscreenDevices();
-  for (const auto& touchscreen : touchscreens) {
-    if (touchscreen.id == id)
-      return touchscreen;
-  }
-
-  return ui::TouchscreenDevice();
-}
-
-// Given an array of touch point and display point pairs, this function computes
-// and returns the constants(defined below) using a least fit algorithm.
-// If (xt, yt) is a touch point then its corresponding (xd, yd) would be defined
-// by the following 2 equations:
-// xd = xt * A + yt * B + C
-// yd = xt * D + yt * E + F
-// This function computes A, B, C, D, E and F and sets |ctm| with the calibrated
-// transform matrix. In case the computation fails, the function will return
-// false.
-// See http://crbug.com/672293
-bool GetCalibratedTransform(
-    std::array<std::pair<gfx::Point, gfx::Point>, 4> touch_point_pairs,
-    const gfx::Transform& pre_calibration_tm,
-    gfx::Transform* ctm) {
-  // Transform the display points before solving the equation.
-  // If the calibration was performed at a resolution that is 0.5 times the
-  // current resolution, then the display points (x, y) for a given touch point
-  // now represents a display point at (2 * x, 2 * y). This and other kinds of
-  // similar tranforms can be applied using |pre_calibration_tm|.
-  for (int row = 0; row < 4; row++)
-    pre_calibration_tm.TransformPoint(&touch_point_pairs[row].first);
-
-  // Vector of the X-coordinate of display points corresponding to each of the
-  // touch points.
-  SkVector4 display_points_x(
-      touch_point_pairs[0].first.x(), touch_point_pairs[1].first.x(),
-      touch_point_pairs[2].first.x(), touch_point_pairs[3].first.x());
-  // Vector of the Y-coordinate of display points corresponding to each of the
-  // touch points.
-  SkVector4 display_points_y(
-      touch_point_pairs[0].first.y(), touch_point_pairs[1].first.y(),
-      touch_point_pairs[2].first.y(), touch_point_pairs[3].first.y());
-
-  // Initialize |touch_point_matrix|
-  // If {(xt_1, yt_1), (xt_2, yt_2), (xt_3, yt_3)....} are a set of touch points
-  // received during calibration, then the |touch_point_matrix| would be defined
-  // as:
-  // |xt_1  yt_1  1  0|
-  // |xt_2  yt_2  1  0|
-  // |xt_3  yt_3  1  0|
-  // |xt_4  yt_4  1  0|
-  SkMatrix44 touch_point_matrix;
-  for (int row = 0; row < 4; row++) {
-    touch_point_matrix.set(row, 0, touch_point_pairs[row].second.x());
-    touch_point_matrix.set(row, 1, touch_point_pairs[row].second.y());
-    touch_point_matrix.set(row, 2, 1);
-    touch_point_matrix.set(row, 3, 0);
-  }
-  SkMatrix44 touch_point_matrix_transpose(touch_point_matrix);
-  touch_point_matrix_transpose.transpose();
-
-  SkMatrix44 product_matrix = touch_point_matrix_transpose * touch_point_matrix;
-
-  // Set (3, 3) = 1 so that |determinent| of the matrix is != 0 and the inverse
-  // can be calculated.
-  product_matrix.set(3, 3, 1);
-
-  SkMatrix44 product_matrix_inverse;
-
-  // NOTE: If the determinent is zero then the inverse cannot be computed. The
-  // only solution is to restart touch calibration and get new points from user.
-  if (!product_matrix.invert(&product_matrix_inverse)) {
-    NOTREACHED() << "Touch Calibration failed. Determinent is zero.";
-    return false;
-  }
-
-  product_matrix_inverse.set(3, 3, 0);
-
-  product_matrix = product_matrix_inverse * touch_point_matrix_transpose;
-
-  // Constants [A, B, C, 0] used to calibrate the x-coordinate of touch input.
-  // x_new = x_old * A + y_old * B + C;
-  SkVector4 x_constants = product_matrix * display_points_x;
-  // Constants [D, E, F, 0] used to calibrate the y-coordinate of touch input.
-  // y_new = x_old * D + y_old * E + F;
-  SkVector4 y_constants = product_matrix * display_points_y;
-
-  // Create a transform matrix using the touch calibration data.
-  ctm->ConcatTransform(gfx::Transform(
-      x_constants.fData[0], x_constants.fData[1], 0, x_constants.fData[2],
-      y_constants.fData[0], y_constants.fData[1], 0, y_constants.fData[2], 0, 0,
-      1, 0, 0, 0, 0, 1));
-  return true;
-}
-
-// Returns an uncalibrated touch transform.
-gfx::Transform GetUncalibratedTransform(
-    const gfx::Transform& tm,
-    const display::ManagedDisplayInfo& display,
-    const display::ManagedDisplayInfo& touch_display,
-    const gfx::SizeF& touch_area,
-    const gfx::SizeF& touch_native_size) {
-  gfx::SizeF current_size(display.bounds_in_native().size());
-  gfx::Transform ctm(tm);
-  // Take care of panel fitting only if supported. Panel fitting is emulated
-  // in software mirroring mode (display != touch_display).
-  // If panel fitting is enabled then the aspect ratio is preserved and the
-  // display is scaled acordingly. In this case blank regions would be present
-  // in order to center the displayed area.
-  if (display.is_aspect_preserving_scaling() ||
-      display.id() != touch_display.id()) {
-    float touch_calib_ar =
-        touch_native_size.width() / touch_native_size.height();
-    float current_ar = current_size.width() / current_size.height();
-
-    if (current_ar > touch_calib_ar) {  // Letterboxing
-      ctm.Translate(
-          0, (1 - current_ar / touch_calib_ar) * 0.5 * current_size.height());
-      ctm.Scale(1, current_ar / touch_calib_ar);
-    } else if (touch_calib_ar > current_ar) {  // Pillarboxing
-      ctm.Translate(
-          (1 - touch_calib_ar / current_ar) * 0.5 * current_size.width(), 0);
-      ctm.Scale(touch_calib_ar / current_ar, 1);
-    }
-  }
-  // Take care of scaling between touchscreen area and display resolution.
-  ctm.Scale(current_size.width() / touch_area.width(),
-            current_size.height() / touch_area.height());
-  return ctm;
-}
-
-}  // namespace
-
-// This is to compute the scale ratio for the TouchEvent's radius. The
-// configured resolution of the display is not always the same as the touch
-// screen's reporting resolution, e.g. the display could be set as
-// 1920x1080 while the touchscreen is reporting touch position range at
-// 32767x32767. Touch radius is reported in the units the same as touch position
-// so we need to scale the touch radius to be compatible with the display's
-// resolution. We compute the scale as
-// sqrt of (display_area / touchscreen_area)
-double TouchTransformerController::GetTouchResolutionScale(
-    const display::ManagedDisplayInfo& touch_display,
-    const ui::TouchscreenDevice& touch_device) const {
-  if (touch_device.id == ui::InputDevice::kInvalidId ||
-      touch_device.size.IsEmpty() ||
-      touch_display.bounds_in_native().size().IsEmpty())
-    return 1.0;
-
-  double display_area = touch_display.bounds_in_native().size().GetArea();
-  double touch_area = touch_device.size.GetArea();
-  double ratio = std::sqrt(display_area / touch_area);
-
-  VLOG(2) << "Display size: "
-          << touch_display.bounds_in_native().size().ToString()
-          << ", Touchscreen size: " << touch_device.size.ToString()
-          << ", Touch radius scale ratio: " << ratio;
-  return ratio;
-}
-
-gfx::Transform TouchTransformerController::GetTouchTransform(
-    const display::ManagedDisplayInfo& display,
-    const display::ManagedDisplayInfo& touch_display,
-    const ui::TouchscreenDevice& touchscreen,
-    const gfx::Size& framebuffer_size) const {
-  auto current_size = gfx::SizeF(display.bounds_in_native().size());
-  auto touch_native_size = gfx::SizeF(touch_display.GetNativeModeSize());
-#if defined(USE_OZONE)
-  auto touch_area = gfx::SizeF(touchscreen.size);
-#elif defined(USE_X11)
-  // On X11 touches are reported in the framebuffer coordinate space.
-  auto touch_area = gfx::SizeF(framebuffer_size);
-#endif
-
-  gfx::Transform ctm;
-
-  if (current_size.IsEmpty() || touch_native_size.IsEmpty() ||
-      touch_area.IsEmpty() || touchscreen.id == ui::InputDevice::kInvalidId)
-    return ctm;
-
-#if defined(USE_OZONE)
-  // Translate the touch so that it falls within the display bounds. This
-  // should not be performed if the displays are mirrored.
-  if (display.id() == touch_display.id()) {
-    ctm.Translate(display.bounds_in_native().x(),
-                  display.bounds_in_native().y());
-  }
-#endif
-
-  // If touch calibration data is unavailable, use naive approach.
-  if (!touch_display.has_touch_calibration_data()) {
-    return GetUncalibratedTransform(ctm, display, touch_display, touch_area,
-                                    touch_native_size);
-  }
-
-  // The resolution at which the touch calibration was performed.
-  gfx::SizeF touch_calib_size(touch_display.GetTouchCalibrationData().bounds);
-
-  // Any additional transfomration that needs to be applied to the display
-  // points, before we solve for the final transform.
-  gfx::Transform pre_transform;
-
-  if (display.id() != touch_display.id() ||
-      display.is_aspect_preserving_scaling()) {
-    // Case of displays being mirrored or in panel fitting mode.
-    // Aspect ratio of the touch display's resolution during calibration.
-    float calib_ar = touch_calib_size.width() / touch_calib_size.height();
-    // Aspect ratio of the display that is being mirrored.
-    float current_ar = current_size.width() / current_size.height();
-
-    if (current_ar < calib_ar) {
-      pre_transform.Scale(current_size.height() / touch_calib_size.height(),
-                          current_size.height() / touch_calib_size.height());
-      pre_transform.Translate(
-          (current_ar / calib_ar - 1.f) * touch_calib_size.width() * 0.5f, 0);
-    } else {
-      pre_transform.Scale(current_size.width() / touch_calib_size.width(),
-                          current_size.width() / touch_calib_size.width());
-      pre_transform.Translate(
-          0, (calib_ar / current_ar - 1.f) * touch_calib_size.height() * 0.5f);
-    }
-  } else {
-    // Case of current resolution being different from the resolution when the
-    // touch calibration was performed.
-    pre_transform.Scale(current_size.width() / touch_calib_size.width(),
-                        current_size.height() / touch_calib_size.height());
-  }
-  // Solve for coefficients and compute transform matrix.
-  gfx::Transform stored_ctm;
-  if (!GetCalibratedTransform(
-          touch_display.GetTouchCalibrationData().point_pairs, pre_transform,
-          &stored_ctm)) {
-    // TODO(malaykeshav): This can be checked at the calibration step before
-    // storing the calibration associated data. This will allow us to explicitly
-    // inform the user with proper UX.
-
-    // Clear stored calibration data.
-    GetDisplayManager()->ClearTouchCalibrationData(touch_display.id());
-
-    // Return uncalibrated transform.
-    return GetUncalibratedTransform(ctm, display, touch_display, touch_area,
-                                    touch_native_size);
-  }
-
-  stored_ctm.ConcatTransform(ctm);
-  return stored_ctm;
-}
-
-TouchTransformerController::TouchTransformerController() {
-  Shell::GetInstance()->window_tree_host_manager()->AddObserver(this);
-}
-
-TouchTransformerController::~TouchTransformerController() {
-  Shell::GetInstance()->window_tree_host_manager()->RemoveObserver(this);
-}
-
-void TouchTransformerController::UpdateTouchRadius(
-    const display::ManagedDisplayInfo& display) const {
-  ui::DeviceDataManager* device_manager = ui::DeviceDataManager::GetInstance();
-  for (const auto& device_id : display.input_devices()) {
-    device_manager->UpdateTouchRadiusScale(
-        device_id,
-        GetTouchResolutionScale(display, FindTouchscreenById(device_id)));
-  }
-}
-
-void TouchTransformerController::UpdateTouchTransform(
-    int64_t target_display_id,
-    const display::ManagedDisplayInfo& touch_display,
-    const display::ManagedDisplayInfo& target_display) const {
-  ui::DeviceDataManager* device_manager = ui::DeviceDataManager::GetInstance();
-  gfx::Size fb_size =
-      Shell::GetInstance()->display_configurator()->framebuffer_size();
-  for (const auto& device_id : touch_display.input_devices()) {
-    device_manager->UpdateTouchInfoForDisplay(
-        target_display_id, device_id,
-        GetTouchTransform(target_display, touch_display,
-                          FindTouchscreenById(device_id), fb_size));
-  }
-}
-
-void TouchTransformerController::UpdateTouchTransformer() const {
-  ui::DeviceDataManager* device_manager = ui::DeviceDataManager::GetInstance();
-  device_manager->ClearTouchDeviceAssociations();
-
-  // Display IDs and display::ManagedDisplayInfo for mirror or extended mode.
-  int64_t display1_id = display::kInvalidDisplayId;
-  int64_t display2_id = display::kInvalidDisplayId;
-  display::ManagedDisplayInfo display1;
-  display::ManagedDisplayInfo display2;
-  // Display ID and display::ManagedDisplayInfo for single display mode.
-  int64_t single_display_id = display::kInvalidDisplayId;
-  display::ManagedDisplayInfo single_display;
-
-  WindowTreeHostManager* window_tree_host_manager =
-      Shell::GetInstance()->window_tree_host_manager();
-  display::DisplayManager* display_manager = GetDisplayManager();
-  if (display_manager->num_connected_displays() == 0) {
-    return;
-  } else if (display_manager->num_connected_displays() == 1 ||
-             display_manager->IsInUnifiedMode()) {
-    single_display_id = display_manager->first_display_id();
-    DCHECK(single_display_id != display::kInvalidDisplayId);
-    single_display = display_manager->GetDisplayInfo(single_display_id);
-    UpdateTouchRadius(single_display);
-  } else {
-    display::DisplayIdList list = display_manager->GetCurrentDisplayIdList();
-    display1_id = list[0];
-    display2_id = list[1];
-    DCHECK(display1_id != display::kInvalidDisplayId &&
-           display2_id != display::kInvalidDisplayId);
-    display1 = display_manager->GetDisplayInfo(display1_id);
-    display2 = display_manager->GetDisplayInfo(display2_id);
-    UpdateTouchRadius(display1);
-    UpdateTouchRadius(display2);
-  }
-
-  if (display_manager->IsInMirrorMode()) {
-    int64_t primary_display_id =
-        window_tree_host_manager->GetPrimaryDisplayId();
-    if (GetDisplayManager()->SoftwareMirroringEnabled()) {
-      // In extended but software mirroring mode, there is a WindowTreeHost for
-      // each display, but all touches are forwarded to the primary root
-      // window's WindowTreeHost.
-      display::ManagedDisplayInfo target_display =
-          primary_display_id == display1_id ? display1 : display2;
-      UpdateTouchTransform(target_display.id(), display1, target_display);
-      UpdateTouchTransform(target_display.id(), display2, target_display);
-    } else {
-      // In mirror mode, there is just one WindowTreeHost and two displays. Make
-      // the WindowTreeHost accept touch events from both displays.
-      UpdateTouchTransform(primary_display_id, display1, display1);
-      UpdateTouchTransform(primary_display_id, display2, display2);
-    }
-    return;
-  }
-
-  if (display_manager->num_connected_displays() > 1) {
-    // In actual extended mode, each display is associated with one
-    // WindowTreeHost.
-    UpdateTouchTransform(display1_id, display1, display1);
-    UpdateTouchTransform(display2_id, display2, display2);
-    return;
-  }
-
-  // Single display mode. The WindowTreeHost has one associated display id.
-  UpdateTouchTransform(single_display_id, single_display, single_display);
-}
-
-void TouchTransformerController::OnDisplaysInitialized() {
-  UpdateTouchTransformer();
-}
-
-void TouchTransformerController::OnDisplayConfigurationChanged() {
-  UpdateTouchTransformer();
-}
-
-}  // namespace ash