Remove unnecessary UI element math.

chrome/browser/android/vr_shell/ui_scene.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 "chrome/browser/android/vr_shell/ui_scene.h"
 
 #include <string>
 #include <utility>
 
 #include "base/memory/ptr_util.h"
@@ skipping 125 matching lines @@
       result = base::MakeUnique<easing::EaseInOut>(pow);
       break;
     }
   }
   return result;
 }
 
 void ApplyAnchoring(const ContentRectangle& parent,
                     XAnchoring x_anchoring,
                     YAnchoring y_anchoring,
-                    ReversibleTransform* transform) {
+                    Transform* transform) {
   // To anchor a child, use the parent's size to find its edge.
   float x_offset;
   switch (x_anchoring) {
     case XLEFT:
       x_offset = -0.5f * parent.size.x;
       break;
     case XRIGHT:
       x_offset = 0.5f * parent.size.x;
       break;
     case XNONE:
@@ skipping 166 matching lines @@
         RemoveAnimation(element_id, animation_id);
         break;
       }
       case Command::UPDATE_BACKGROUND:
         UpdateBackgroundFromDict(*data);
         break;
     }
   }
 }
 
-void UiScene::UpdateTransforms(float screen_tilt, int64_t time_in_micro) {
+void UiScene::UpdateTransforms(int64_t time_in_micro) {
   // Process all animations before calculating object transforms.
   for (auto& element : ui_elements_) {
     element->Animate(time_in_micro);
   }
   for (auto& element : ui_elements_) {
-    element->transform.MakeIdentity();
-    element->transform.Scale(element->size.x, element->size.y, element->size.z);
+    Transform transform;
+    transform.MakeIdentity();
+    transform.Scale(element->size.x, element->size.y, element->size.z);
     element->computed_opacity = 1.0f;
-    ApplyRecursiveTransforms(*element.get(), &element->transform,
+    ApplyRecursiveTransforms(*element.get(), &transform,
                              &element->computed_opacity);
-    element->transform.Rotate(1.0f, 0.0f, 0.0f, screen_tilt);

[cjgrant, 2017/03/03 21:30:34]

Whoa, this looks broken, and the unit tests don't catch it.

[mthiesse, 2017/03/06 17:26:07]

THAT explains a lot. I thought recentering was doing weird things and not
actually centering.

[cjgrant, 2017/03/06 17:43:34]

Oops, disregard, this block is fine.

[cjgrant, 2017/03/06 17:43:34]

Since my original comment was not valid, I need to ask you what you meant by
this.

[mthiesse, 2017/03/06 17:46:00]

We can follow up offline and make sure I'm not crazy. Feel free to submit as-is.

+    element->SetTransform(transform);
   }
 }
 
 ContentRectangle* UiScene::GetUiElementById(int element_id) {
   for (auto& element : ui_elements_) {
     if (element->id == element_id) {
       return element.get();
     }
   }
   return nullptr;
@@ skipping 10 matching lines @@
 const std::vector<std::unique_ptr<ContentRectangle>>& UiScene::GetUiElements()
     const {
   return ui_elements_;
 }
 
 UiScene::UiScene() = default;
 
 UiScene::~UiScene() = default;
 
 void UiScene::ApplyRecursiveTransforms(const ContentRectangle& element,
-                                       ReversibleTransform* transform,
+                                       Transform* transform,
                                        float* opacity) {
   transform->Scale(element.scale.x, element.scale.y, element.scale.z);
   transform->Rotate(element.rotation.x, element.rotation.y, element.rotation.z,
                     element.rotation.angle);
   transform->Translate(element.translation.x, element.translation.y,
                        element.translation.z);
   *opacity *= element.opacity;
 
   if (element.parent_id >= 0) {
     const ContentRectangle* parent = GetUiElementById(element.parent_id);
     CHECK(parent != nullptr);
     ApplyAnchoring(*parent, element.x_anchoring, element.y_anchoring,
                    transform);
+
     ApplyRecursiveTransforms(*parent, transform, opacity);
   }
 }
 
 void UiScene::ApplyDictToElement(const base::DictionaryValue& dict,
                                  ContentRectangle* element) {
   int parent_id;
 
   if (ParseInt(dict, "parentId", &parent_id)) {
     CHECK_GE(parent_id, 0);
@@ skipping 57 matching lines @@
         content_element_ = element;
         break;
       default:
         element->fill = Fill::NONE;
         break;
     }
   }
 }
 
 }  // namespace vr_shell