[Remoting Android] Cursor & Cursor Feedback for OpenGL Renderer

remoting/client/gl_cursor_feedback.cc

+// 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.
+
+#include "remoting/client/gl_cursor_feedback.h"
+
+#include <math.h>
+#include <array>
+
+#include "base/logging.h"
+#include "remoting/client/gl_canvas.h"
+#include "remoting/client/gl_cursor_feedback_texture.h"
+#include "remoting/client/gl_math.h"
+#include "remoting/client/gl_render_layer.h"
+
+namespace {
+
+const int kTextureId = 2;

[Sergey Ulanov, 2016/07/21 19:28:48]

maybe not for this CL: would it be useful to have a shared header define all
texture ids to avoid conflicts?

[Yuwei, 2016/07/21 21:44:41]

Acknowledged. Will send another CL for this.

+const float kAnimationDurationMs = 220.f;
+
+}  // namespace
+
+namespace remoting {
+
+GlCursorFeedback::GlCursorFeedback() {}
+
+GlCursorFeedback::~GlCursorFeedback() {}
+
+void GlCursorFeedback::SetCanvas(GlCanvas* canvas) {
+  if (!canvas) {
+    layer_.reset();
+    return;
+  }
+  layer_.reset(new GlRenderLayer(kTextureId, canvas));
+  GlCursorFeedbackTexture* texture = GlCursorFeedbackTexture::GetInstance();
+  layer_->SetTexture(texture->GetTexture(), texture->GetTextureDiameter(),
+                     texture->GetTextureDiameter());
+}
+
+void GlCursorFeedback::StartAnimation(float normalized_x,
+                                      float normalized_y,
+                                      float normalized_width,
+                                      float normalized_height) {
+  max_width_ = normalized_width;
+  max_height_ = normalized_height;
+  cursor_x_ = normalized_x;
+  cursor_y_ = normalized_y;
+  animation_start_time_ = base::TimeTicks::Now();
+}
+
+bool GlCursorFeedback::Draw() {
+  if (!layer_ || animation_start_time_.is_null()) {
+    return false;
+  }
+  float progress =
+      (base::TimeTicks::Now() - animation_start_time_).InMilliseconds() /
+      kAnimationDurationMs;
+  if (progress > 1) {
+    animation_start_time_ = base::TimeTicks();
+    return false;
+  }
+  float width = progress * max_width_;
+  float height = progress * max_height_;
+  std::array<float, 8> positions;
+  FillRectangleVertexPositions(cursor_x_ - width / 2, cursor_y_ - height / 2,
+                               width, height, &positions);
+  layer_->SetVertexPositions(positions);
+  layer_->Draw(1.f - progress);
+  return true;
+}
+
+}  // namespace remoting