| // Copyright 2016 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_DISPLAY_CANVAS_H_ |
| #define REMOTING_CLIENT_DISPLAY_CANVAS_H_ |
| |
| #include <array> |
| |
| #include "base/macros.h" |
| #include "base/memory/weak_ptr.h" |
| |
| namespace remoting { |
| |
| // This class holds zoom and pan configurations of the canvas and is used to |
| // draw textures on the canvas. |
| class Canvas { |
| public: |
| Canvas() {} |
| virtual ~Canvas() {} |
| |
| // Clears the frame. |
| virtual void Clear() = 0; |
| |
| // Sets the transformation matrix. This matrix defines how the canvas should |
| // be shown on the view. |
| // 3 by 3 transformation matrix, [ m0, m1, m2, m3, m4, m5, m6, m7, m8 ]. |
| // The matrix will be multiplied with the positions (with projective space, |
| // (x, y, 1)) to draw the textures with the right zoom and pan configuration. |
| // |
| // | m0, m1, m2, | | x | |
| // | m3, m4, m5, | * | y | |
| // | m6, m7, m8 | | 1 | |
| // |
| // For a typical transformation matrix such that m1=m3=m6=m7=0 and m8=1, m0 |
| // and m4 defines the scaling factor of the canvas and m2 and m5 defines the |
| // offset of the upper-left corner in pixel. |
| virtual void SetTransformationMatrix(const std::array<float, 9>& matrix) = 0; |
| |
| // Sets the size of the view in pixels such that it fills up the the whole |
| // viewport. |
| // Note that this only affects the transformation matrix. It doesn't affect |
| // how the viewport is rendered on the screen. |
| virtual void SetViewSize(int width, int height) = 0; |
| |
| // Draws the texture on the canvas. Nothing will happen if |
| // SetNormalizedTransformation() has not been called. |
| // vertex_buffer: reference to the 2x4x2 float vertex buffer. |
| // [ four (x, y) position of the texture vertices in pixel |
| // with respect to the canvas, |
| // four (x, y) position of the vertices in percentage |
| // defining the visible area of the texture ] |
| // alpha_multiplier: Will be multiplied with the alpha channel of the texture. |
| // Passing 1 means no change of the transparency of the |
| // texture. |
| virtual void DrawTexture(int texture_id, |
| int texture_handle, |
| int vertex_buffer, |
| float alpha_multiplier) = 0; |
| |
| // Version if applicable to implementation. Default 0 if unused. |
| virtual int GetVersion() const = 0; |
| |
| // Returns the maximum texture resolution limitation. Neither the width nor |
| // the height of the texture can exceed this limitation. |
| virtual int GetMaxTextureSize() const = 0; |
| |
| // Intended to be given to a Drawable to draw onto. |
| virtual base::WeakPtr<Canvas> GetWeakPtr() = 0; |
| |
| private: |
| DISALLOW_COPY_AND_ASSIGN(Canvas); |
| }; |
| |
| } // namespace remoting |
| |
| #endif // REMOTING_CLIENT_DISPLAY_CANVAS_H_ |