Proposal: Grid Enhancements

Contents

• Introduction
• References
• Requirements
• Constraints
• Discussion
• Use Cases
• Grid line style and color
• Diagram Properties
• Size validation
• Grid Visibility
• Considered Approaches
• Design Artifacts
• Future Considerations
• Test Cases
• Grid line style and color
• Diagram Properties
• Size validation
• Grid Visibility

Introduction

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This document defines a set of enhancements to the diagram grid functionality present in the Graphical Modeling Framework (GMF). The goal of the enhancements is to help with the usability and discoverability of the grids and their feature set.

The following Bugzilla reports will be considered in this proposal:

* These enhancements will be implemented for M4.

References

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• Eclipse documentation and code base (Eclipse SDK 3.1.0)
• The Graphical Modeling Framework project (GMF)
• The Graphical Editing Framework project (GEF)

Requirements

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This feature must address the following high-level requirements:

* Under consideration

Constraints

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The feature is subject to the following design constraints:

• Backward compatibility: Ensure backward compatibility for any meta-model changes

Discussion

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The enhancements chosen for implementation reflect the most important missing functionality for the grid feature set. Enhancement E8 was chosen because it will be very easy to implement.

The remaining items will not be implemented because they represent minor inconveniences or possibly enhancements that are not required. E5 was not chosen because the GEF request will provide GMF with the proper functionality for this enhancement.

Use Cases for intended implementation

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Select the use case title to expand the details.

1. Grid line style and color

• Brief description

  A diagram grid's line style (solid, dashed or dotted), transparency and color will be configurable from the diagram's context menu and the main diagram menu.

  Addresses

  E1

  Flow of events

  -The user creates a new diagram or opens an existing diagram with the grid visible. The user may also set the grid visible.

  -The user may now select a diagram's context menu and Diagram menu to modify the active diagram's grid line.

2. Diagram Properties

   • Brief description

     The properties view should reflect the diagram grid properties (visibility, spacing, line style, transparency, order and color). The properties view would support a separate grid tab. Here is a mock up of the grid properties tab with a subset of the intended property set.

     

     Addresses

     E2, E9, E10

     Flow of events

     -The user creates a new diagram or opens an existing diagram with the grid visible. The user may also set the grid visible.

     -The user chooses to show the properties view with the active diagram in focus.

     - The diagram properties Advanced Tab displays the View > Grid table item with sub items: visibility, spacing, line style and color.

3. Size validation

   • Brief description

     The grid spacing preference value will accommodate spacing of equal value for each presented unit of measure.

     Addresses

     E8

     Flow of events

     -The user sets the maximum grid spacing for any of the units of measure

     -The user switches to another unit of measure without error

     Corollary: If the user exceeds the maximum for any unit measure then switching will also display an error

4. Grid Visibility

   • Brief description

     There grid order (i.e. grid in front/back of shapes) will be a property of the diagram and the user will be able to change the setting on the fly.

     Addresses

     E1

     Flow of events

     • -The user creates a new diagram or opens an existing diagram with the grid visible. The user may also set the grid visible.

     • -The user adds some diagram objects to the diagram.

     • -The grid will be rendered above/below the new objects based on the diagram property, even when nested or multiple objects overlap one another.

Considered Approaches

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The grid properties could be persisted in the meta-model or remain as workspace viewer properties. I believe that the current solution is best because the grid feature is used as a helper for diagram arrangement and is not intrinsically part of the diagram. The properties should be expanded to accommodate all aforementioned grid properties. The preferences should also reflect new feature defaults.

Design Artifacts

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Future Considerations

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1. The grid spacing may be increased using a resize arrow above the grid lines.
   
    

2. A specific context menu could be generated for the grid. This would bring up a "Grid Settings" dialog that would include grid visibility, spacing, line style and color.
   
    

3. Independent grid spacing on the X and Y axis

4. Grid functionality tied to the ruler

Test Cases for intended implementation

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Select the test case title to expand the details.

1. Grid line style and color

• Create a new logic diagram and use the diagram context menu to set the grid visibility to true.
• Use the diagram context menu View > Grid to launch the Grid Settings dialog.
• Test all settings and ensure that the grid lines reflect each change.
   

2. Diagram Properties

• Create a new logic diagram and use the diagram context menu to set the grid visibility to true.
• Use the diagram context menu Show Properties View.
• Select the Advanced Tab and test the Grid table entry settings.
• Ensure that the grid lines reflect each change.
   

3. Size validation

• Select the Window > Preferences... menu item.
• Select the Logic Diagrams > Rulers and Grid tree item.
• Test each unit of measure for a maximum allowable value (e.g. < 100 inches)
• Ensure that each remaining unit of measure supports an equivalent number of corresponding units (e.g. < 9600 pixels)
   

4. Grid Visibility

• Create a new logic diagram and use the diagram context menu to set the grid visibility to true.
• Create multiple diagram shapes on the diagram including overlapping objects.
• Ensure that the grid lines are visible over all shapes when the grid order property is set to front.
• Ensure that the grid lines are not visible over shapes when the grid order property is set to back.