Moving the GL implementation details into a sub folder for client display.

remoting/client/gl_canvas.h

-// 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_OPENGL_GL_CANVAS_H_
-#define REMOTING_CLIENT_OPENGL_GL_CANVAS_H_
-
-#include <array>
-
-#include "base/macros.h"
-#include "base/threading/thread_checker.h"
-#include "remoting/client/sys_opengl.h"
-
-namespace remoting {
-
-// This class holds zoom and pan configurations of the canvas and is used to
-// draw textures on the canvas.
-// Must be constructed after the OpenGL surface is created and destroyed before
-// the surface is destroyed.
-class GlCanvas {
- public:
-  // gl_version: version number of the OpenGL ES context. Either 2 or 3.
-  GlCanvas(int gl_version);
-
-  ~GlCanvas();
-
-  // 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.
-  void SetTransformationMatrix(const std::array<float, 9>& matrix);
-
-  // Sets the size of the view in pixels.
-  void SetViewSize(int width, int height);
-
-  // 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.
-  void DrawTexture(int texture_id,
-                   GLuint texture_handle,
-                   GLuint vertex_buffer,
-                   float alpha_multiplier);
-
-  // Returns the version number of current OpenGL ES context. Either 2 or 3.
-  int GetGlVersion() const;
-
-  // Returns the maximum texture resolution limitation. Neither the width nor
-  // the height of the texture can exceed this limitation.
-  int GetMaxTextureSize() const;
-
- private:
-  int gl_version_;
-
-  int max_texture_size_ = 0;
-  bool transformation_set_ = false;
-  bool view_size_set_ = false;
-
-  // Handles.
-  GLuint vertex_shader_;
-  GLuint fragment_shader_;
-  GLuint program_;
-
-  // Locations of the corresponding shader attributes.
-  GLuint transform_location_;
-  GLuint view_size_location_;
-  GLuint texture_location_;
-  GLuint alpha_multiplier_location_;
-  GLuint position_location_;
-  GLuint tex_cord_location_;
-
-  base::ThreadChecker thread_checker_;
-
-  DISALLOW_COPY_AND_ASSIGN(GlCanvas);
-};
-
-}  // namespace remoting
-
-#endif  // REMOTING_CLIENT_OPENGL_GL_CANVAS_H_