VrShell: implement insecure content warning display

chrome/browser/android/vr_shell/vr_shell.cc

Index: chrome/browser/android/vr_shell/vr_shell.cc
diff --git a/chrome/browser/android/vr_shell/vr_shell.cc b/chrome/browser/android/vr_shell/vr_shell.cc
index 0eb5a06b11f81fa994bbdfaab47dfcca4781a223..0d340367a114f3ea8beac5dd48185489fb9447cb 100644
--- a/chrome/browser/android/vr_shell/vr_shell.cc
+++ b/chrome/browser/android/vr_shell/vr_shell.cc
@@ -250,6 +250,9 @@ void VrShell::DrawFrame(JNIEnv* env, const JavaParamRef<jobject>& obj) {
 
   if (webvr_mode_) {
     DrawWebVr();
+    if (!webvr_secure_origin_) {
+      DrawWebVrOverlay(target_time.monotonic_system_time_nanos);
+    }
   } else {
     DrawVrShell(target_time.monotonic_system_time_nanos);
   }
@@ -405,10 +408,86 @@ void VrShell::DrawWebVr() {
 
   glViewport(0, 0, render_size_.width, render_size_.height);
   vr_shell_renderer_->GetWebVrRenderer()->Draw(content_texture_id_);
+}
 
-  if (!webvr_secure_origin_) {
-    // TODO(klausw): Draw the insecure origin warning here.
+void VrShell::DrawWebVrOverlay(int64_t present_time_nanos) {
+  // Draw WebVR security warning overlays for each eye. This uses
+  // the eye-from-head matrices but not the pose, goal is to place
+  // the icons in an eye-relative position so that they follow along
+  // with head rotations.
+
+  gvr::Mat4f left_eye_view_matrix =
+      gvr_api_->GetEyeFromHeadMatrix(GVR_LEFT_EYE);
+  gvr::Mat4f right_eye_view_matrix =
+      gvr_api_->GetEyeFromHeadMatrix(GVR_RIGHT_EYE);
+
+  buffer_viewport_list_->GetBufferViewport(GVR_LEFT_EYE,
+                                           buffer_viewport_.get());
+  DrawWebVrEye(left_eye_view_matrix, *buffer_viewport_, present_time_nanos);
+  buffer_viewport_list_->GetBufferViewport(GVR_RIGHT_EYE,
+                                           buffer_viewport_.get());
+  DrawWebVrEye(right_eye_view_matrix, *buffer_viewport_, present_time_nanos);
+}
+
+void VrShell::DrawWebVrEye(const gvr::Mat4f& view_matrix,
+                           const gvr::BufferViewport& params,
+                           int64_t present_time_nanos) {
+  gvr::Recti pixel_rect =
+      CalculatePixelSpaceRect(render_size_, params.GetSourceUv());
+  glViewport(pixel_rect.left, pixel_rect.bottom,
+             pixel_rect.right - pixel_rect.left,
+             pixel_rect.top - pixel_rect.bottom);
+  glScissor(pixel_rect.left, pixel_rect.bottom,
+            pixel_rect.right - pixel_rect.left,
+            pixel_rect.top - pixel_rect.bottom);
+
+  gvr::Mat4f projection_matrix =
+      PerspectiveMatrixFromView(params.GetSourceFov(), kZNear, kZFar);
+
+  // If the UI texture hasn't been initialized yet, we can't draw yet.
+  if (ui_tex_width_ == 0.0f || ui_tex_height_ == 0.0f) {
+    return;
   }
+
+  // Draw insecure content warning icons.
+  const float warning_depth = 0.7f;  // Distance in meters.
+
+  // Show IDS_WEBSITE_SETTINGS_INSECURE_WEBVR_CONTENT_PERMANENT text.
+  gvr::Mat4f icon_pos;
+  SetIdentityM(icon_pos);
+  const float small_icon_width = 2 * 0.15f * warning_depth;
+  const float small_icon_height = small_icon_width / 2.0f;  // 2:1 aspect.
+  const float small_icon_angle = 20.0f * M_PI / 180.f;  // Degrees to radians.
+  ScaleM(icon_pos, icon_pos, small_icon_width, small_icon_height, 1.0f);
+  TranslateM(icon_pos, icon_pos, 0.0f, 0.0f, -warning_depth);
+  icon_pos = MatrixMul(
+      QuatToMatrix(QuatFromAxisAngle(1.f, 0.f, 0.f, small_icon_angle)),
+      icon_pos);
+  gvr::Mat4f combined = MatrixMul(projection_matrix,
+                                  MatrixMul(view_matrix, icon_pos));
+  Rectf copy_rect = {256.f / ui_tex_width_, 0.f / ui_tex_height_,
+                     128.f / ui_tex_width_, 64.f / ui_tex_height_};
+  vr_shell_renderer_->GetTexturedQuadRenderer()->Draw(
+      ui_texture_id_, combined, copy_rect);
+
+  // Check if we also need to show the transient warning.
+  if (present_time_nanos > webvr_warning_end_nanos_) {
+    return;
+  }
+
+  // Show IDS_WEBSITE_SETTINGS_INSECURE_WEBVR_CONTENT_TRANSIENT text.
+  SetIdentityM(icon_pos);
+  const float large_icon_width = 2 * 0.25f * warning_depth;
+  const float large_icon_height = large_icon_width / 2.0f;  // 2:1 aspect.
+  ScaleM(icon_pos, icon_pos, large_icon_width, large_icon_height, 1.0f);
+  TranslateM(icon_pos, icon_pos, 0.0f, 0.0f, -warning_depth);
+  combined = MatrixMul(projection_matrix,
+                       MatrixMul(view_matrix, icon_pos));
+  copy_rect = {0.f / ui_tex_width_, 0.f / ui_tex_height_,
+               256.f / ui_tex_width_, 128.f / ui_tex_height_};
+  vr_shell_renderer_->GetTexturedQuadRenderer()->Draw(
+      ui_texture_id_, combined, copy_rect);
+
 }
 
 void VrShell::OnPause(JNIEnv* env, const JavaParamRef<jobject>& obj) {
@@ -447,6 +526,13 @@ void VrShell::SetWebVrMode(JNIEnv* env,
                            const base::android::JavaParamRef<jobject>& obj,
                            bool enabled) {
   webvr_mode_ = enabled;
+  if (enabled) {
+    const int64_t warning_seconds = 30;
+    int64_t now = gvr::GvrApi::GetTimePointNow().monotonic_system_time_nanos;
+    webvr_warning_end_nanos_ = now + warning_seconds * 1000 * 1000 * 1000;
+  } else {
+    webvr_warning_end_nanos_ = 0;
+  }
 }
 
 void VrShell::SetWebVRSecureOrigin(bool secure_origin) {