// SPDX-FileCopyrightText: Copyright 2024 yuzu Emulator Project
// SPDX-License-Identifier: GPL-3.0-or-later
#include "common/math_util.h"
#include "hid_core/resources/touch_screen/gesture_handler.h"
namespace Service::HID {
constexpr f32 Square(s32 num) {
return static_cast<f32>(num * num);
}
GestureHandler::GestureHandler() {}
GestureHandler::~GestureHandler() {}
void GestureHandler::SetTouchState(std::span<TouchState> touch_state, u32 count, s64 timestamp) {
gesture = {};
gesture.active_points = std::min(MaxPoints, static_cast<std::size_t>(count));
for (size_t id = 0; id < gesture.active_points; ++id) {
const auto& [active_x, active_y] = touch_state[id].position;
gesture.points[id] = {
.x = static_cast<s32>(active_x),
.y = static_cast<s32>(active_y),
};
gesture.mid_point.x += static_cast<s32>(gesture.points[id].x / gesture.active_points);
gesture.mid_point.y += static_cast<s32>(gesture.points[id].y / gesture.active_points);
}
for (size_t id = 0; id < gesture.active_points; ++id) {
const f32 distance = std::sqrt(Square(gesture.mid_point.x - gesture.points[id].x) +
Square(gesture.mid_point.y - gesture.points[id].y));
gesture.average_distance += distance / static_cast<f32>(gesture.active_points);
}
gesture.angle = std::atan2(static_cast<f32>(gesture.mid_point.y - gesture.points[0].y),
static_cast<f32>(gesture.mid_point.x - gesture.points[0].x));
gesture.detection_count = last_gesture.detection_count;
if (last_update_timestamp > timestamp) {
timestamp = last_tap_timestamp;
}
time_difference = static_cast<f32>(timestamp - last_update_timestamp) / (1000 * 1000 * 1000);
}
bool GestureHandler::NeedsUpdate() {
if (force_update) {
force_update = false;
return true;
}
// Update if coordinates change
for (size_t id = 0; id < MaxPoints; id++) {
if (gesture.points[id] != last_gesture.points[id]) {
return true;
}
}
// Update on press and hold event after 0.5 seconds
if (last_gesture_state.type == GestureType::Touch && last_gesture_state.point_count == 1 &&
time_difference > PressDelay) {
return enable_press_and_tap;
}
return false;
}
void GestureHandler::UpdateGestureState(GestureState& next_state, s64 timestamp) {
last_update_timestamp = timestamp;
GestureType type = GestureType::Idle;
GestureAttribute attributes{};
// Reset next state to default
next_state.sampling_number = last_gesture_state.sampling_number + 1;
next_state.delta = {};
next_state.vel_x = 0;
next_state.vel_y = 0;
next_state.direction = GestureDirection::None;
next_state.rotation_angle = 0;
next_state.scale = 0;
if (gesture.active_points > 0) {
if (last_gesture.active_points == 0) {
NewGesture(type, attributes);
} else {
UpdateExistingGesture(next_state, type);
}
} else {
EndGesture(next_state, type, attributes);
}
// Apply attributes
next_state.detection_count = gesture.detection_count;
next_state.type = type;
next_state.attributes = attributes;
next_state.pos = gesture.mid_point;
next_state.point_count = static_cast<s32>(gesture.active_points);
next_state.points = gesture.points;
last_gesture = gesture;
last_gesture_state = next_state;
}
void GestureHandler::NewGesture(GestureType& type, GestureAttribute& attributes) {
gesture.detection_count++;
type = GestureType::Touch;
// New touch after cancel is not considered new
if (last_gesture_state.type != GestureType::Cancel) {
attributes.is_new_touch.Assign(1);
enable_press_and_tap = true;
}
}
void GestureHandler::UpdateExistingGesture(GestureState& next_state, GestureType& type) {
// Promote to pan type if touch moved
for (size_t id = 0; id < MaxPoints; id++) {
if (gesture.points[id] != last_gesture.points[id]) {
type = GestureType::Pan;
break;
}
}
// Number of fingers changed cancel the last event and clear data
if (gesture.active_points != last_gesture.active_points) {
type = GestureType::Cancel;
enable_press_and_tap = false;
gesture.active_points = 0;
gesture.mid_point = {};
gesture.points.fill({});
return;
}
// Calculate extra parameters of panning
if (type == GestureType::Pan) {
UpdatePanEvent(next_state, type);
return;
}
// Promote to press type
if (last_gesture_state.type == GestureType::Touch) {
type = GestureType::Press;
}
}
void GestureHandler::EndGesture(GestureState& next_state, GestureType& type,
GestureAttribute& attributes) {
if (last_gesture.active_points != 0) {
switch (last_gesture_state.type) {
case GestureType::Touch:
if (enable_press_and_tap) {
SetTapEvent(type, attributes);
return;
}
type = GestureType::Cancel;
force_update = true;
break;
case GestureType::Press:
case GestureType::Tap:
case GestureType::Swipe:
case GestureType::Pinch:
case GestureType::Rotate:
type = GestureType::Complete;
force_update = true;
break;
case GestureType::Pan:
EndPanEvent(next_state, type);
break;
default:
break;
}
return;
}
if (last_gesture_state.type == GestureType::Complete ||
last_gesture_state.type == GestureType::Cancel) {
gesture.detection_count++;
}
}
void GestureHandler::SetTapEvent(GestureType& type, GestureAttribute& attributes) {
type = GestureType::Tap;
gesture = last_gesture;
force_update = true;
f32 tap_time_difference =
static_cast<f32>(last_update_timestamp - last_tap_timestamp) / (1000 * 1000 * 1000);
last_tap_timestamp = last_update_timestamp;
if (tap_time_difference < DoubleTapDelay) {
attributes.is_double_tap.Assign(1);
}
}
void GestureHandler::UpdatePanEvent(GestureState& next_state, GestureType& type) {
next_state.delta = gesture.mid_point - last_gesture_state.pos;
next_state.vel_x = static_cast<f32>(next_state.delta.x) / time_difference;
next_state.vel_y = static_cast<f32>(next_state.delta.y) / time_difference;
last_pan_time_difference = time_difference;
// Promote to pinch type
if (std::abs(gesture.average_distance - last_gesture.average_distance) > PinchThreshold) {
type = GestureType::Pinch;
next_state.scale = gesture.average_distance / last_gesture.average_distance;
}
const f32 angle_between_two_lines = std::atan((gesture.angle - last_gesture.angle) /
(1 + (gesture.angle * last_gesture.angle)));
// Promote to rotate type
if (std::abs(angle_between_two_lines) > AngleThreshold) {
type = GestureType::Rotate;
next_state.scale = 0;
next_state.rotation_angle = angle_between_two_lines * 180.0f / Common::PI;
}
}
void GestureHandler::EndPanEvent(GestureState& next_state, GestureType& type) {
next_state.vel_x =
static_cast<f32>(last_gesture_state.delta.x) / (last_pan_time_difference + time_difference);
next_state.vel_y =
static_cast<f32>(last_gesture_state.delta.y) / (last_pan_time_difference + time_difference);
const f32 curr_vel =
std::sqrt((next_state.vel_x * next_state.vel_x) + (next_state.vel_y * next_state.vel_y));
// Set swipe event with parameters
if (curr_vel > SwipeThreshold) {
SetSwipeEvent(next_state, type);
return;
}
// End panning without swipe
type = GestureType::Complete;
next_state.vel_x = 0;
next_state.vel_y = 0;
force_update = true;
}
void GestureHandler::SetSwipeEvent(GestureState& next_state, GestureType& type) {
type = GestureType::Swipe;
gesture = last_gesture;
force_update = true;
next_state.delta = last_gesture_state.delta;
if (std::abs(next_state.delta.x) > std::abs(next_state.delta.y)) {
if (next_state.delta.x > 0) {
next_state.direction = GestureDirection::Right;
return;
}
next_state.direction = GestureDirection::Left;
return;
}
if (next_state.delta.y > 0) {
next_state.direction = GestureDirection::Down;
return;
}
next_state.direction = GestureDirection::Up;
}
} // namespace Service::HID
