Icod.Terminal 1.12.0 — advanced persistent-raster placement geometry

[uniblab]

Summary

Begins Icod.Terminal 1.12.0 development from published 1.11.1.

The approved release theme is bounded advanced persistent-raster placement geometry:

• pixel-space source rectangles;
• signed z-order;
• no relative-placement graph, Unicode placeholder, animation, or scene-graph expansion.

Before the new public placement surface lands, T121 performs the already-approved behavior-preserving table-driven cleanup of TerminalTermInfoSemanticEvidence.

Planned tranches

T120  architecture/API regret gate + roadmap normalization            accepted
T121  table-drive TerminalTermInfoSemanticEvidence                    in progress
T122  source-rectangle public contract + resource-aware validation     planned
T123  z-order public contract + validation                             planned
T124  create/update encoder and acknowledged placement integration     planned
T125  lifecycle/adversarial/boundary hardening                         planned
T126  sample/package-only consumer/XML docs/downstream qualification   planned
T127  API freeze/release docs/three-OS/package release closure         planned

Frozen direction

Planned public additions:

public readonly struct TerminalRasterSourceRectangle {
    public TerminalRasterSourceRectangle(int x, int y, int width, int height);
    public int X { get; }
    public int Y { get; }
    public int Width { get; }
    public int Height { get; }
}

public sealed class TerminalRasterPlacementOptions {
    public int? Columns { get; set; }
    public int? Rows { get; set; }
    public TerminalRasterSourceRectangle? SourceRectangle { get; set; }
    public int? ZIndex { get; set; }
}

Source rectangles must fit completely inside the uploaded source raster; the common API does not inherit backend clipping behavior. ZIndex uses the full signed 32-bit range. Existing current-cursor/no-cursor-movement placement semantics remain intact.

Compatibility guardrails

• stable compatibility floor remains 1.0.0;
• production dependencies remain Icod.TermInfo 1.11.0 and Icod.Timing 1.0.0;
• no new TerminalCapability value is planned;
• private resource/placement identities remain private;
• no source raster byte cache or replay/re-upload behavior;
• existing resource/placement ceilings remain 256 / 4096;
• direct persistent transfer remains the reviewed transport;
• 1.11 placement bytes/behavior remain unchanged when new options are unused.

Current development identity

1.12.0-alpha.1

Authorities

• Icod.Terminal-1.12.0-Development-Roadmap.md
• docs/T120-1.12.0-Architecture-and-API-Regret-Gate.md
• docs/superpowers/specs/2026-09-12-1.12.0-advanced-raster-placement-design.md
• docs/superpowers/plans/2026-09-12-1.12.0-advanced-raster-placement.md

T121 implementation begins from this planning/API-regret gate. The PR remains draft while the implementation tranches advance.