C++ Input::GetTouch方法代码示例

//------------------------------------------------------------------------------------------------------------------------------------------------------
void BaseApplication::HandleSceneUpdate(StringHash eventType, VariantMap& eventData)
{
    // Move the camera by touch, if the camera node is initialized by descendant sample class
    if (touchEnabled_ && cameraNode_)
    {
        Input* input = GetSubsystem<Input>();
        for (unsigned i = 0; i < input->GetNumTouches(); ++i)
        {
            TouchState* state = input->GetTouch(i);
            if (!state->touchedElement_)    // Touch on empty space
            {
                if (state->delta_.x_ ||state->delta_.y_)
                {
                    Camera* camera = cameraNode_->GetComponent<Camera>();
                    if (!camera)
                        return;

                    Graphics* graphics = GetSubsystem<Graphics>();
                    yaw_ += TOUCH_SENSITIVITY * camera->GetFov() / graphics->GetHeight() * state->delta_.x_;
                    pitch_ += TOUCH_SENSITIVITY * camera->GetFov() / graphics->GetHeight() * state->delta_.y_;

                    // Construct new orientation for the camera scene node from yaw and pitch; roll is fixed to zero
                    cameraNode_->SetRotation(Quaternion(pitch_, yaw_, 0.0f));
                }
                else
                {
                    // Move the cursor to the touch position
                    Cursor* cursor = GetSubsystem<UI>()->GetCursor();
                    if (cursor && cursor->IsVisible())
                        cursor->SetPosition(state->position_);
                }
            }
        }
    }
}

void Touch::UpdateTouches(Controls& controls) // Called from HandleUpdate
{
    zoom_ = false; // reset bool

    Input* input = GetSubsystem<Input>();

    // Zoom in/out
    if (input->GetNumTouches() == 2)
    {
        TouchState* touch1 = input->GetTouch(0);
        TouchState* touch2 = input->GetTouch(1);

        // Check for zoom pattern (touches moving in opposite directions and on empty space)
        if (!touch1->touchedElement_ && !touch2->touchedElement_ && ((touch1->delta_.y_ > 0 && touch2->delta_.y_ < 0) || (touch1->delta_.y_ < 0 && touch2->delta_.y_ > 0)))
            zoom_ = true;
        else
            zoom_ = false;

        if (zoom_)
        {
            int sens = 0;
            // Check for zoom direction (in/out)
            if (Abs(touch1->position_.y_ - touch2->position_.y_) > Abs(touch1->lastPosition_.y_ - touch2->lastPosition_.y_))
                sens = -1;
            else
                sens = 1;
            cameraDistance_ += Abs(touch1->delta_.y_ - touch2->delta_.y_) * sens * touchSensitivity_ / 50.0f;
            cameraDistance_ = Clamp(cameraDistance_, CAMERA_MIN_DIST, CAMERA_MAX_DIST); // Restrict zoom range to [1;20]
        }
    }

    // Gyroscope (emulated by SDL through a virtual joystick)
    if (useGyroscope_ && input->GetNumJoysticks() > 0)  // numJoysticks = 1 on iOS & Android
    {
        JoystickState* joystick = input->GetJoystickByIndex(0);
        if (joystick->GetNumAxes() >= 2)
        {
            if (joystick->GetAxisPosition(0) < -GYROSCOPE_THRESHOLD)
                controls.Set(CTRL_LEFT, true);
            if (joystick->GetAxisPosition(0) > GYROSCOPE_THRESHOLD)
                controls.Set(CTRL_RIGHT, true);
            if (joystick->GetAxisPosition(1) < -GYROSCOPE_THRESHOLD)
                controls.Set(CTRL_FORWARD, true);
            if (joystick->GetAxisPosition(1) > GYROSCOPE_THRESHOLD)
                controls.Set(CTRL_BACK, true);
        }
    }
}

void UIDrag::HandleUpdate(StringHash eventType, VariantMap& eventData)
{
    UI* ui = GetSubsystem<UI>();
    UIElement* root = ui->GetRoot();

    Input* input = GetSubsystem<Input>();

    unsigned n = input->GetNumTouches();
    for (unsigned i = 0; i < n; i++)
    {
        Text* t = (Text*)root->GetChild("Touch " + String(i));
        TouchState* ts = input->GetTouch(i);
        t->SetText("Touch " + String(ts->touchID_));

        IntVector2 pos = ts->position_;
        pos.y_ -= 30;

        t->SetPosition(pos);
        t->SetVisible(true);
    }

    for (unsigned i = n; i < 10; i++)
    {
        Text* t = (Text*)root->GetChild("Touch " + String(i));
        t->SetVisible(false);
    }
    
    if (input->GetKeyPress(KEY_SPACE))
    {
        PODVector<UIElement*> elements;
        root->GetChildrenWithTag(elements, "SomeTag");
        for (PODVector<UIElement*>::ConstIterator i = elements.Begin(); i != elements.End(); ++i)
        {
            UIElement* element = *i;
            element->SetVisible(!element->IsVisible());
        }
    }
}

void VehicleDemo::HandleUpdate(StringHash eventType, VariantMap& eventData)
{
    using namespace Update;

    Input* input = GetSubsystem<Input>();

    if (vehicle_)
    {
        UI* ui = GetSubsystem<UI>();

        // Get movement controls and assign them to the vehicle component. If UI has a focused element, clear controls
        if (!ui->GetFocusElement())
        {
            vehicle_->controls_.Set(CTRL_FORWARD, input->GetKeyDown(KEY_W));
            vehicle_->controls_.Set(CTRL_BACK, input->GetKeyDown(KEY_S));
            vehicle_->controls_.Set(CTRL_LEFT, input->GetKeyDown(KEY_A));
            vehicle_->controls_.Set(CTRL_RIGHT, input->GetKeyDown(KEY_D));

            // Add yaw & pitch from the mouse motion or touch input. Used only for the camera, does not affect motion
            if (touchEnabled_)
            {
                for (unsigned i = 0; i < input->GetNumTouches(); ++i)
                {
                    TouchState* state = input->GetTouch(i);
                    if (!state->touchedElement_)    // Touch on empty space
                    {
                        Camera* camera = cameraNode_->GetComponent<Camera>();
                        if (!camera)
                            return;

                        Graphics* graphics = GetSubsystem<Graphics>();
                        vehicle_->controls_.yaw_ += TOUCH_SENSITIVITY * camera->GetFov() / graphics->GetHeight() * state->delta_.x_;
                        vehicle_->controls_.pitch_ += TOUCH_SENSITIVITY * camera->GetFov() / graphics->GetHeight() * state->delta_.y_;
                    }
                }
            }
            else
            {
                vehicle_->controls_.yaw_ += (float)input->GetMouseMoveX() * YAW_SENSITIVITY;
                vehicle_->controls_.pitch_ += (float)input->GetMouseMoveY() * YAW_SENSITIVITY;
            }
            // Limit pitch
            vehicle_->controls_.pitch_ = Clamp(vehicle_->controls_.pitch_, 0.0f, 80.0f);

            // Check for loading / saving the scene
            if (input->GetKeyPress(KEY_F5))
            {
                File saveFile(context_, GetSubsystem<FileSystem>()->GetProgramDir() + "Data/Scenes/VehicleDemo.xml",
                    FILE_WRITE);
                scene_->SaveXML(saveFile);
            }
            if (input->GetKeyPress(KEY_F7))
            {
                File loadFile(context_, GetSubsystem<FileSystem>()->GetProgramDir() + "Data/Scenes/VehicleDemo.xml", FILE_READ);
                scene_->LoadXML(loadFile);
                // After loading we have to reacquire the weak pointer to the Vehicle component, as it has been recreated
                // Simply find the vehicle's scene node by name as there's only one of them
                Node* vehicleNode = scene_->GetChild("Vehicle", true);
                if (vehicleNode)
                    vehicle_ = vehicleNode->GetComponent<Vehicle>();
            }
        }
        else
            vehicle_->controls_.Set(CTRL_FORWARD | CTRL_BACK | CTRL_LEFT | CTRL_RIGHT, false);
    }
}

void CharacterDemo::HandleUpdate(StringHash eventType, VariantMap& eventData)
{
    using namespace Update;

    Input* input = GetSubsystem<Input>();

    if (character_)
    {
        // Clear previous controls
        character_->controls_.Set(CTRL_FORWARD | CTRL_BACK | CTRL_LEFT | CTRL_RIGHT | CTRL_JUMP, false);

        // Update controls using touch utility class
        if (touch_)
            touch_->UpdateTouches(character_->controls_);

        // Update controls using keys
        UI* ui = GetSubsystem<UI>();
        if (!ui->GetFocusElement())
        {
            if (!touch_ || !touch_->useGyroscope_)
            {
                character_->controls_.Set(CTRL_FORWARD, input->GetKeyDown(KEY_W));
                character_->controls_.Set(CTRL_BACK, input->GetKeyDown(KEY_S));
                character_->controls_.Set(CTRL_LEFT, input->GetKeyDown(KEY_A));
                character_->controls_.Set(CTRL_RIGHT, input->GetKeyDown(KEY_D));
            }
            character_->controls_.Set(CTRL_JUMP, input->GetKeyDown(KEY_SPACE));

            // Add character yaw & pitch from the mouse motion or touch input
            if (touchEnabled_)
            {
                for (unsigned i = 0; i < input->GetNumTouches(); ++i)
                {
                    TouchState* state = input->GetTouch(i);
                    if (!state->touchedElement_)    // Touch on empty space
                    {
                        Camera* camera = cameraNode_->GetComponent<Camera>();
                        if (!camera)
                            return;

                        Graphics* graphics = GetSubsystem<Graphics>();
                        character_->controls_.yaw_ += TOUCH_SENSITIVITY * camera->GetFov() / graphics->GetHeight() * state->delta_.x_;
                        character_->controls_.pitch_ += TOUCH_SENSITIVITY * camera->GetFov() / graphics->GetHeight() * state->delta_.y_;
                    }
                }
            }
            else
            {
                character_->controls_.yaw_ += (float)input->GetMouseMoveX() * YAW_SENSITIVITY;
                character_->controls_.pitch_ += (float)input->GetMouseMoveY() * YAW_SENSITIVITY;
            }
            // Limit pitch
            character_->controls_.pitch_ = Clamp(character_->controls_.pitch_, -80.0f, 80.0f);
            // Set rotation already here so that it's updated every rendering frame instead of every physics frame
            character_->GetNode()->SetRotation(Quaternion(character_->controls_.yaw_, Vector3::UP));

            // Switch between 1st and 3rd person
            if (input->GetKeyPress(KEY_F))
                firstPerson_ = !firstPerson_;

            // Turn on/off gyroscope on mobile platform
            if (touch_ && input->GetKeyPress(KEY_G))
                touch_->useGyroscope_ = !touch_->useGyroscope_;

            // Check for loading / saving the scene
            if (input->GetKeyPress(KEY_F5))
            {
                File saveFile(context_, GetSubsystem<FileSystem>()->GetProgramDir() + "Data/Scenes/CharacterDemo.xml", FILE_WRITE);
                scene_->SaveXML(saveFile);
            }
            if (input->GetKeyPress(KEY_F7))
            {
                File loadFile(context_, GetSubsystem<FileSystem>()->GetProgramDir() + "Data/Scenes/CharacterDemo.xml", FILE_READ);
                scene_->LoadXML(loadFile);
                // After loading we have to reacquire the weak pointer to the Character component, as it has been recreated
                // Simply find the character's scene node by name as there's only one of them
                Node* characterNode = scene_->GetChild("Jack", true);
                if (characterNode)
                    character_ = characterNode->GetComponent<Character>();
            }
        }
    }
}