GridObjectCollection layout: anchor parent to left/center/right and top/middle/bottom

[julenka]

Overview

The current GridObjectCollection will tile the objects with the parent object in the center of the collection - this great if you have a collection that you want to appear in the middle of something, but if you have a UI where you have a grid of buttons, which you want to appear going from the top left of a place and then growing toward the bottom right, this makes things difficult (you need to duplicate the layout logic to figure out where the buttons will be, and then move the parent object to JUST the right location).

This change adds the ability to lay out the buttons so that the parent is in the left/center/right x top/middle/bottom of the collection.

Changes

• Fixes: Adding tile direction aka "anchor" aka "alignment" support to GridObjectCollection #4777

• Add a new field named "anchor" to specify how objects should be tiled. Works with all types of surfaces.
  

• Adds tests to verify that all anchor layouts tile content correctly

• When layout type is "Columns then rows", ask user to specify number of columns instead of number of rows.
  
  

• Modify Rows and Columns property so that users cannot change rows if layout type is ColumnsThenRows, and vice versa

Breaking changes

• If any assets have layout type "ColumnThenRow", update your asset to specify number of columns that should exist in your grid.

To Do

• Remove breaking change by fixing up asset or offering button on validate to fix incorrect row / columns
• Add documentation for this change describing anchor. Also add explanations around layout fields

Verification

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[wiwei]

using System;

// Copyright (c) Microsoft Corporation.
// Licensed under the MIT License.

https://docs.opensource.microsoft.com/content/releasing/copyright-headers.html

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Refers to: Assets/MixedRealityToolkit.Examples/Demos/UX/Collections/Scripts/GridObjectLayoutControl.cs:1 in 77406ff. [](commit_id = 77406ff, deletion_comment = False)

[radicalad]

Love it. Could we mitigate the breaking change by falling back to the row property if the collection is already set up? Perhaps check the layout type and column count and then set it from row?

[ritijain]

nit: only UpdateCollection on value change

[wiwei]

I think the same comment applies to the LayoutOrder one too!

[julenka]

Thought about why the other fields don't call UpdateCollection() after and realized this is because you may want to change multiple properties in a frame, and only need to recompute once. Decided to follow that existing pattern to save on layout compute.

[ritijain]

are the AnchorType properties applicable to other surfaceTypes as well ?

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Refers to: Assets/MixedRealityToolkit.SDK/Features/UX/Scripts/Collections/GridObjectCollection.cs:19 in 77406ff. [](commit_id = 77406ff, deletion_comment = False)

[keveleigh]

/azp run

[azure-pipelines]

Azure Pipelines successfully started running 2 pipeline(s).

[ritijain]

@julenka - PR looks good to me, however I had a few broader concerns regarding the feature -

1. There is no documentation attached to this PR, going over the usage of the new properties introduced. Having documentation for this is critical since it prevents the exercise of folks trying to checkout the repo and launch the scene or dig through code to discover these properties.

2. Calling the feature "GridObjectCollection" is a bit misleading, when the script's "Layout" property also support Horizontal and Vertical Layouts. Again the documentation for this is missing (https://microsoft.github.io/MixedRealityToolkit-Unity/Documentation/README_ObjectCollection.html)

I would prefer if 1 above is addressed in this PR. For 2 - in general we would all benefit from opening another issue for improving the documentation of this feature.

[keveleigh]

Looks like .NET validation is failing with

Assets\MixedRealityToolkit.Examples\Demos\UX\Collections\Scripts\GridObjectLayoutControl.cs(108,50): error CS1503: Argument 1: cannot convert from 'string' to 'System.IO.Stream'

[julenka]

There is no documentation attached to this PR, going over the usage of the new properties introduced. Having documentation for this is critical since it prevents the exercise of folks trying to checkout the repo and launch the scene or dig through code to discover these properties.

Great point! I had thought maybe it's not needed since the grid object collection docs are already pretty broad, but actually those docs could be improved. I'll add it as a to do for this PR. Thanks for the great feedback @ritijain!

[david-c-kline]

/azp run

[azure-pipelines]

Azure Pipelines successfully started running 2 pipeline(s).

[julenka]

/azp run

[julenka]

/azp run

[azure-pipelines]

Azure Pipelines successfully started running 2 pipeline(s).

[julenka]

@cre8ivepark friendly ping. Would especially appreciate your input regarding the layout of the example scene:

[david-c-kline]

@julenka, that scene looks wonderful!

[keveleigh]

/azp run

[azure-pipelines]

Azure Pipelines successfully started running 2 pipeline(s).

[cre8ivepark]

Updated the text to use Segoe UI Semibold font, a small adjustment in the layout

[keveleigh]

@cre8ivepark Small comment on your image, but the top right layout color looks kinda like the "missing material magenta". The bottom right one has some outlining it looks like, but I'm not sure about the top right one.

Not sure if it's just the image or something we want to update.

[cre8ivepark]

@keveleigh Oh, it is just spectrum color change when it viewed from a different angle.