| // Copyright 2017 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. |
| |
| #ifndef REMOTING_CLIENT_UI_DESKTOP_VIEWPORT_H_ |
| #define REMOTING_CLIENT_UI_DESKTOP_VIEWPORT_H_ |
| |
| #include "base/callback.h" |
| #include "remoting/client/ui/view_matrix.h" |
| |
| namespace remoting { |
| |
| // The viewport is a sliding window on the desktop image. This class defines |
| // the viewport's position and size, provides methods to manipulate it, and |
| // outputs a desktop space -> surface space transformation matrix for drawing |
| // the desktop onto the client's view surface on the screen. |
| // |
| // Desktop space: Coordinates to locate a point on the host's desktop image in |
| // pixels, similar to the mouse's cursor position. |
| // Surface space: Coordinates to locate a point on the client device's view |
| // surface (e.g. GLKView/SurfaceView) for rendering the desktop, this is |
| // often the coordinate system to locate a point on the user's phone |
| // screen (if the surface expands to the whole screen). |
| // |
| // Viewport: Projection of the user surface view on the desktop space. |
| // Desktop: Projection of the host's desktop on the surface space. |
| // |
| // You may either manipulate the desktop on the surface coordinate or manipulate |
| // the viewport on the desktop coordinate, depending on your choice of the |
| // reference frame. |
| class DesktopViewport { |
| public: |
| using TransformationCallback = |
| base::RepeatingCallback<void(const ViewMatrix&)>; |
| |
| DesktopViewport(); |
| ~DesktopViewport(); |
| |
| // Sets the |desktop_size_| and (re)initializes the viewport. |
| void SetDesktopSize(int desktop_width, int desktop_height); |
| |
| // Sets the |surface_size_| and (re)initializes the viewport. |
| void SetSurfaceSize(int surface_width, int surface_height); |
| |
| // Sets insets on the surface area to allow viewport to be panned out of them. |
| // Should be used to adjust for system UI like soft keyboard and screen |
| // notches/cutouts. |
| // This method effectively shrinks the size of the viewport on the surface. |
| // You may want to call this before SetSurfaceSize() so that safe insets are |
| // taken into account when initializing viewport. |
| void SetSafeInsets(int left, int top, int right, int bottom); |
| |
| // Translates the desktop on the surface's reference frame by <dx, dy>. |
| void MoveDesktop(float dx, float dy); |
| |
| // Scales the desktop on the surface's reference frame at pivot point (px, py) |
| // by |scale|. |
| void ScaleDesktop(float px, float py, float scale); |
| |
| // Moves the viewport center by <x, y> on the desktop's coordinate. |
| void MoveViewport(float dx, float dy); |
| |
| // Sets the viewport center to (x, y) on the desktop's coordinate. |
| void SetViewportCenter(float x, float y); |
| |
| // Returns the current center of the viewport on the desktop's coordinate. |
| ViewMatrix::Point GetViewportCenter() const; |
| |
| // Returns true if |point| is within the bounds of the desktop. |
| bool IsPointWithinDesktopBounds(const ViewMatrix::Point& point) const; |
| |
| // True if desktop size and surface size are set. |
| bool IsViewportReady() const; |
| |
| // Constrains |point| within the bounds of the desktop. Do nothing if the |
| // desktop size is not set. |
| ViewMatrix::Point ConstrainPointToDesktop( |
| const ViewMatrix::Point& point) const; |
| |
| // Registers the callback to be called once the transformation has changed. |
| // run_immediately: If true and the viewport is ready to be used, the callback |
| // will be called immedately with the transformation matrix. |
| void RegisterOnTransformationChangedCallback( |
| const TransformationCallback& callback, |
| bool run_immediately); |
| |
| // Returns the reference to the desktop-to-surface transformation. |
| const ViewMatrix& GetTransformation() const; |
| |
| private: |
| struct Bounds { |
| float left; |
| float top; |
| float right; |
| float bottom; |
| }; |
| |
| // Resizes the desktop such that the image is displayed without borders in |
| // minimum possible zoom-level. This will be called once both the desktop |
| // and the surface size are set. |
| void ResizeToFit(); |
| |
| // Adjusts the size and position of the viewport so that the constrains always |
| // hold, then feed the matrix to |on_transformation_changed_|. |
| void UpdateViewport(); |
| |
| // Gets a rectangle of all possible positions where the viewport's center can |
| // locate. |
| Bounds GetViewportCenterBounds() const; |
| |
| // Gets the size of |surface_size_| inset by |safe_insets_|. |
| ViewMatrix::Vector2D GetSurfaceSafeAreaSize() const; |
| |
| // Translates the viewport on the desktop's reference frame by <dx, dy>, |
| // without calling UpdateViewport(). |
| void MoveViewportWithoutUpdate(float dx, float dy); |
| |
| // Moves the point inside the bounds with minimum displacement if it is out of |
| // the bounds. |
| static ViewMatrix::Point ConstrainPointToBounds( |
| const Bounds& bounds, |
| const ViewMatrix::Point& point); |
| |
| ViewMatrix::Vector2D desktop_size_{0.f, 0.f}; |
| ViewMatrix::Vector2D surface_size_{0.f, 0.f}; |
| Bounds safe_insets_{0, 0, 0, 0}; |
| |
| ViewMatrix desktop_to_surface_transform_; |
| |
| TransformationCallback on_transformation_changed_; |
| |
| // DesktopViewport is neither copyable nor movable. |
| DesktopViewport(const DesktopViewport&) = delete; |
| DesktopViewport& operator=(const DesktopViewport&) = delete; |
| }; |
| |
| } // namespace remoting |
| #endif // REMOTING_CLIENT_UI_DESKTOP_VIEWPORT_H_ |