# HyperTwist Phase 7D MagicTile renderer-port decision packet

Created on `2026-06-19`

## Status

- first-party HyperTwist packet
- spec-only `Phase 7D` decision/control slice
- no implementation widening is granted by this packet
- adjacent evidence status on `2026-06-19`: the current embedded-browser lane
  was audited in
  `docs/arch/HYPERTWIST_PHASE7D_MAGICTILE_RENDERER_PORT_EVIDENCE_AUDIT_2026-06-19.md`
  and the verdict remained explicit `No-Go`

## Purpose

This packet turns the newly landed `Phase 7C` native behavior proof seam into
an explicit go/no-go decision gate for any later native `MagicTile`
renderer-port widening.

The granted slice is:

- define the decision posture for future native spherical or hyperbolic
  renderer ownership
- require future widening to prove a real browser-host gap rather than assume
  one
- bind any future native renderer work to the already landed first-party
  `Phase 7C` behavior proof seam

It is not:

- a renderer implementation packet
- a `WinForms` / `OpenTK` host-shell transplant
- a generic non-Euclidean runtime-base replacement
- a reversal of the landed embedded browser/CEF shipping posture

## Current authority basis

This decision packet stands on:

- `docs/ops/HYPERTWIST_COMPREHENSIVE_RECONSTRUCTION_ROADMAP_2026-06-10.md`
- `docs/v6_5_deep_manual_pack/HyperTwist/ROADMAP.md`
- `docs/v6_5_deep_manual_pack/HyperTwist/ARCHITECTURE.md`
- `docs/v6_5_deep_manual_pack/HyperTwist/FEATURE_REGISTRY.md`
- `docs/ops/HYPERTWIST_IMPLEMENTATION_PHASE_1_KICKOFF.md`
- `docs/arch/HYPERTWIST_PHASE7C_MAGICTILE_NATIVE_BEHAVIOR_PROOF_IMPLEMENTATION_PACKET_2026-06-19.md`
- `docs/arch/HYPERTWIST_PHASE8B_OPTIONAL_FULL_BROWSER_CLIENT_HTTP_BACKEND_PREPARATION_PACKET_2026-06-19.md`

The routing facts now accepted are:

- `Phase 7A` already chose the embedded browser/CEF shell as the live
  `MagicTile` host posture
- `Phase 7B` already established first-party tiling state envelopes, shared
  scramble normalization, and unified timer continuity
- `Phase 7C` already established the first-party native behavior proof seam
  for selected-cell focus, candidate-twist disambiguation, preview, commit or
  cancel, and timer continuity
- the optional full-browser client path remains a separate spec-only branch
  rather than the same decision as native renderer ownership

## Default posture

The default renderer-port decision is now `No-Go`.

Future native renderer widening stays closed by default unless a later packet
explicitly satisfies all required go criteria in this document.

## Required go criteria

Any future native renderer packet may reopen only if all of the following are
made explicit first:

1. the request names a concrete first shipping target:
   - one puzzle family or geometry family
   - one explicit projection/view posture
   - one bounded interaction surface above the landed `Phase 7C` seam
2. the request demonstrates a real browser-host insufficiency that remains
   after using the landed browser shell, browser-state bridge, and `Phase 7C`
   proof seam as intended
3. the request reuses the landed `Phase 7C` proof vocabulary as the required
   behavior contract:
   - selected-cell focus
   - candidate-twist disambiguation
   - preview token
   - commit or cancel semantics
   - timer continuity
4. the request keeps the owned widening bounded to first-party renderer
   surfaces rather than broad host-shell or runtime-base replacement
5. the request provides an explicit validation plan containing:
   - canonical Windows Unreal build validation
   - focused new renderer-facing automation
   - regression reruns for `HyperTwist.FirstParty.MagicTile`,
     `HyperTwist.Browser`, and `HyperTwist.Permissive.MagicTile`
6. the request preserves current authority boundaries:
   - no direct `WinForms` / `OpenTK` transplant
   - no donor renderer literal carryover
   - no authority inversion away from first-party runtime ownership

## Immediate no-go criteria

Future native renderer widening remains an explicit `No-Go` if any of the
following are true:

1. the request does not identify a concrete browser-host failure beyond
   preference, aesthetics, or speculation
2. the request widens into broad non-Euclidean interaction-shell ownership
   instead of one bounded renderer target
3. the request implicitly reopens legacy `WinForms` / `OpenTK` host-shell
   ownership
4. the request cannot describe how the landed `Phase 7C` proof seam remains
   authoritative during the widening
5. the request omits a real Windows build plus regression-validation plan
6. the request attempts to merge the optional full-browser client path and the
   native renderer path into one forced topology decision

## If-go envelope

If a future packet satisfies the go criteria, the first allowed widening is
still narrow:

- one first-party native renderer pilot packet
- one explicit named puzzle-family/geometry-family target
- one explicit projection/view contract
- one explicit behavior-parity proof above the landed `Phase 7C` seam
- browser-host posture retained as the current shipping lane until the native
  pilot itself is separately validated and accepted

That future green light does not authorize:

- immediate broad runtime replacement
- host-shell replacement
- generic donor-to-native porting
- removal of the landed browser lane as current shipping posture

## If-no-go follow-on

If the decision remains `No-Go`, follow-on work should stay inside already
owned lanes:

- improve the embedded browser shell
- improve browser-side interaction composition
- extend first-party bridge/state vocabulary only where the vocabulary remains
  transport-neutral
- widen the optional full-browser client path only through its own separate
  spec/implementation approvals

## Acceptance criteria

- this packet records that future native `MagicTile` renderer widening is now
  governed by an explicit first-party go/no-go gate
- this packet records that the landed `Phase 7C` proof seam is the required
  behavior authority for any future widening
- this packet records that the default posture remains `No-Go`
- this packet records that browser-host insufficiency, bounded scope, and full
  Windows validation are mandatory prerequisites for any later `Go`

## Validation target

Validate this packet through doc-consistency only:

1. roadmap, architecture, feature-registry, kickoff, and adjacent `Phase 7C`
   / `Phase 8B` packets must agree on the new decision gate
2. no Unreal build or code-validation claim is required for this spec-only
   packet
3. no renderer implementation or ownership claim may be inferred from this
   document

## Queue effect

If this packet lands cleanly:

- the native renderer branch becomes explicitly decision-gated rather than
  loosely deferred
- the default posture remains the landed embedded browser/CEF shell plus the
  landed `Phase 7C` proof seam
- any future renderer-facing widening must first satisfy this packet instead
  of inheriting permission from `Phase 7C` alone
