Milestone (May 11 -> July 5) - Fonts and UI

[Dandielo]

Focused on providing a simple system for font assets and engine trait capable of rendering texts with selected fonts.

The next milestone starting with iteration Vienna (May 11'th)

Milestone: https://github.com/iceshard-engine/engine/milestone/4
Branch: milestone-1105050722

Topic: Fonts and UI

• Implementing font assets and basic rendering.
• Implementing UI with a basic asset definition.

Resulting version change: [major, minor + 1, patch = 0]

Scope

So far this will be focused on the following things (by priority):

• [feature] Very basic Font rendering.
• [feature] Very basic UI Rendering.
• [feature] Definition of a UI asset.
• [tech-debt] Refactor metadata file format and API
• [feature] Very basic asset compiler tool.

Complexity estimations (1, 2, 3, 5, 8)

• [~8] Very basic Font rendering.
  • Complexity is higher due to the amount of work required in total.
  • Should be split into:
    • [2] Loading font assets into memory.
    • [2] Loading glyphs from fonts.
    • [3] Create a font texture from glyphs.
    • [2] Create a renderer that can pick the proper glyphs and render them.
    • [2] Create debug tools for font debugging.
• [~8] Very basic UI Rendering.
  • Needs to be split into:
    • [3] Create a representation for UI objects.
    • [3] Build a basic mesh representation from UI objects.
    • [2] Create debug tools of the UI elements.
    • [2] Allow to display text and textures from UI objects.
• [~5] Definition of a UI asset.
  • [3] Definition of a UI file / asset.
  • [2] Creating UI elements from the asset.
• [2] Refactor metadata file format and API
  • Low complexity, but might require lots of refactoring.
  • Requires a 'view-like' ice::pod::Hash type
• [~5] Very basic asset compiler tool.
  • [3] Research the needs and possibilities of an offline asset compiler tool.
  • Probably not going ot be implemented in this milestone.

Time estimations (rough values in hours)

• [~8] Very basic Font rendering.
  • Complexity is higher due to the amount of work required in total.
  • Should be split into:
    • [2] Loading font assets into memory. (6h)
    • [2] Loading glyphs from fonts. (6h)
    • [3] Create a font texture from glyphs. (10h)
    • [2] Create a renderer that can pick the proper glyphs and render them. (8h)
    • [2] Create debug tools for font debugging. (4h)
• [~8] Very basic UI Rendering.
  • Needs to be split into:
    • [3] Create a representation for UI objects. (8h)
    • [3] Build a basic mesh representation from UI objects. (6h)
    • [2] Create debug tools of the UI elements. (4h)
    • [2] Allow to display text and textures from UI objects. (4h)

---

• [~5] Definition of a UI asset.
  • [3] Definition of a UI file / asset. (4h)
  • [2] Creating UI elements from the asset. (4h)
• [2] Refactor metadata file format and API (4h)
  • Low complexity, but might require lots of refactoring.
  • Requires a 'view-like' ice::pod::Hash type
• [~5] Very basic asset compiler tool.
  • [3] Research the needs and possibilities of an offline asset compiler tool. (8h)
  • Probably not going ot be implemented in this milestone.

Total time for included tasks: 76h
The current milestone limit is: 60h

Resulting stretch goal tasks:

• [~5] Definition of a UI asset.
  • [3] Definition of a UI file / asset. (4h)
  • [2] Creating UI elements from the asset. (4h)
• [2] Refactor metadata file format and API (4h)
  • Low complexity, but might require lots of refactoring.
  • Requires a 'view-like' ice::pod::Hash type
• [~5] Very basic asset compiler tool.
  • [3] Research the needs and possibilities of an offline asset compiler tool. (8h)
  • Probably not going ot be implemented in this milestone.

Final list of issues in this milestone

• Loading font assets into memory. (Research what approaches are used for text rendering with different fonts. #99, Implement loading fonts into memory. #118)
  • Loading glyphs from fonts. (Implement glyph loading into memory. #119)
  • Create a font texture from glyphs. (Create a texture with loaded font glyphs. #120)
  • Create a renderer that can pick the proper glyphs and render them. (Implement text rendering with selected fonts. #101)
  • Create debug tools for text rendering. (Create debug tools for text rendering. #121)
• Create a representation for UI objects. (Implement an in-engine representation for UI objects. #122, Creation of a UI system for IceShard. #76, Implement basic UI systems / traits. #98)
  • Build a basic mesh representation from UI objects. (Build a basic mesh representation from UI objects.  #123)
  • Create debug tools of the UI elements. (Create debug tools of the UI elements. #124)
  • Allow to display text and textures from UI objects. (part of Creation of a UI system for IceShard. #76, Implement basic UI systems / traits. #98)

[Dandielo]

This milestone will be extended by #125 before continuing.

[Dandielo]

As of today, we can properly:

• Create UI objects, render them and test if the mouse is inside.
• We can properly calculate text boundaries required for 'auto' sizes in the UI.
• We can properly layout elements using a VerticalListBox.
• There is a compiletime debug tool for visualizing, bounding, hit and context boxes of some elements.

What is missing still:

• Loading of pre-calculated font atlases from textures / other data.
• Baking fonts with custom character sets. (for example: ひらがな)
• Serializing events from the UI definition.
  • Sending these events into the frame.
• Updating UI after changes were made (ex.: window size)
• Visual customization (colors, textures, borders, etc).
• More element types
• '%' values in size and positions.
• Centering of elements in parent boxes.
• Centering of text.

Due to large amount of work and a still remaining clean-up some of these might not be achievable in this milestone.

[Dandielo]

Pushed today support for UI updates.

• The number of vertices cannot change.
• Values and colors can change.

Prepared initial work for dynamic updates of UI texts.
Made UI definitions much more flexible and properly validating most values.

[Dandielo]

Last few days pushed the following changes:

• Initial suport for setting position of boxes with 'maring=auto'
• Support for resources. Runtime values that are stored in memory and can be updated.
  • These values are not meant to be updated in quick succession as they will always require a full UI rebuild.
• Setting fonts and texts from resources in elements. {Resource <resource_name>} to do so.

New tasks:

• A good 'clean-up' of the game-ui trait. As it's too big in it's current state.
• Brainstorm the actual cases for anchoring, margins and padding. What should work and what not.

[Dandielo]

Finished feature development with very basic styles and quick UI updates. Cleanup remains.

[Dandielo]

Milestone was finished and the engine moved to version v0.2.0.
Due to lots of technical debt accumulated the next milestone will mostly focus on removing it, with smaller features improving the overall API.