Mods are folders with About/About.json metadata; ModLoader resolves a
deterministic load order (dependencies first, ties alphabetical) and
later mods override earlier ones everywhere.
DefDatabase loads JSON def files ({ "type", "defs": [...] }) into
game-registered Def subclasses, with parent inheritance (own fields on
top of the parent's, nested values replaced whole), abstract parents
and full replacement of same-named defs by later mods.
LanguageManager loads Languages/<code>/*.json flat key-string maps,
switches language at runtime and falls back current -> default -> key.
ModContentTree merges one content folder across mods by relative path;
AtlasBuilder gains an explicit-sources Build overload so a merged
texture tree can be packed incrementally at game start.
The LittleSim game now ships its entire content as the Core mod,
demonstrating the module end to end.
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
Collisions: init bucket heads to -1 (QueryAabb hung before the first
rebuild), reset query stamps on truncated QueryAabb (later queries
silently dropped entities), inside-origin raycasts hit at fraction 0 for
circles too, exactly-touching boxes now pair like touching circles.
Graphics: render into the letterbox viewport so the picture matches
ScreenToWorld/WorldToScreen instead of stretching; Y-sort by the
transform pivot rather than the quad center; lock-free snapshot
LayerRegistry (parallel submit read it unsynchronized); validate
InitialCapacity; warn when UseRenderer2D drops options of a later scene.
Core: scenes are explicitly single-use (re-loading threw silently
duplicated systems/entities before — now it throws), Scene.RegisterUnload
for per-scene resources, a switch requested during the reveal phase
covers again instead of hard-swapping, borderless fullscreen
(HardwareModeSwitch off), InputCapture service for input-suppressing
overlays, host disposes the transition renderer and IDisposable services
on shutdown.
Input: game input reads as released while InputCapture is held; mouse
position and wheel freeze so deltas stay zero.
DevConsole: holds InputCapture while open (typing no longer drives the
camera), Revision increments only under the lock, quoted command
arguments, history capped at 256.
UI: scene Desktop skips Myra input processing while the console is open
(clicks no longer fall through), is disposed on scene unload, and Myra
init no longer depends on a process-static flag.
Audio: validate channel count/sample rate before stopping the previous
track, empty looped oggs no longer hang FillBuffers, the instance stops
when a non-looping track drains (IsPlaying was stuck true).
Atlases: metadata v2 stores per-source size+mtime snapshots, so
timestamp-preserving copies and renames invalidate correctly; loader
checks the version and disposes pages on partial load failure; shared
pages never exceed a non-POT MaxPageSize; oversized items pack first
onto exact-size pages instead of splitting an open shared page; the CLI
validates numeric options.
Assets.Generator: file names are escaped in XML docs and string
literals, members no longer collide with the enclosing class (CS0542),
and the Assets root is resolved against build_property.projectdir so
nested "Assets" directories do not shift region paths.
Pathfinding: queries throw when the grid was resized after construction;
generation stamps survive int overflow.
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
The MrGameEng.Sample demo game is deleted along with its assets; the
LittleSim god-sim (which vendors this engine as a submodule) takes over
as the living showcase where every engine feature is demonstrated.
CLAUDE.md, README and docs updated; the demonstration rule now points
to LittleSim, and the stress-scene perf figure is kept as a historical
reference measurement.
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
Pathfinding (depends on Core only): GridPathfinder with A* (octile/
Manhattan heuristic), Dijkstra and BFS over a game-implemented
IPathGrid; 4/8 connectivity, diagonals never cut corners. FlowField +
FlowFieldBuilder (multi-source Dijkstra) give crowds O(1) steering per
agent per frame. All buffers are grid-sized once and invalidated by a
generation stamp - repeated queries allocate nothing and clear nothing.
Collisions (Graphics exception: Transform2D, RectF): Collider component
(circle/AABB, offset, two-way layer masks), CollisionWorld - a uniform
spatial hash on flat arrays rebuilt from scratch each tick (O(n) for
movers, zero alloc after warm-up, deterministic pair order), pair
collection, QueryAabb and closest-hit Raycast. scene.UseCollisions()
registers CollisionSystem after movement systems.
30 new tests (string-map mazes, cost weighting, corner cutting, flow
descent; pair/mask/query/raycast). Sample gains a PathfindingScene
('path' console command): click to set the goal, 250 agents follow the
flow field, the A* path is highlighted, colliding agents flash red.
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
TileSet maps ids to texture regions with tints (0 = empty), TileGrid is a
bounds-checked dense ushort grid, and the Tilemap component places a grid
in the world per render layer. UseTilemaps() inserts TilemapRenderSystem
before the flush; it submits only the camera-visible cell range
(TilemapMath.VisibleCells), so frame cost scales with the screen, not the
grid. Demonstrated in the sample as a checkerboard floor; Tiled loading
stays on the roadmap on top of this API.
AtlasBuilder packs a directory tree of loose images into atlas pages plus
JSON metadata (deterministic shelf packing, incremental rebuilds, orphan
cleanup); TextureAtlas loads them back handing out Texture2DRegions, so
sprites from one page batch into a single draw call. The asset handle
generator maps .atlas files to TextureAtlas and skips page images.
Demonstrated in the sample (Assets/Atlases + 'atlas' console command),
wrapped as tools/MrGameEng.AtlasTool for build scripts.
Documented dependency exception: Atlases depends on Graphics and Assets.
Test projects become executables (OutputType=Exe) as required by v3.
Satisfy the new xUnit1051 analyzer by passing TestContext cancellation
tokens in the generator compilation test.
Load memory_context at session start, search before topic work,
save decisions/bugs/gotchas before ending a session.
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
Core gains a static Log (Debug/Info/Warning/Error + event); the engine
logs key events like scene switches. The console captures Log output
into a 2048-line ring buffer and executes registered commands with
input history (up/down), Tab prefix completion and scrolling
(PageUp/PageDown/End/wheel). Built-ins: help, clear, echo, timescale,
close, quit; games register their own (sample: stress/main/beep).
Console core is pure logic covered by headless tests; the Myra overlay
renders a single label rebuilt only when the Revision counter moves -
an idle or closed console costs nothing per frame. Toggled with the
backquote key; sample gameplay hotkeys are suppressed while open.
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
Five optimizations measured on the 100k-entity stress scene (Release,
vsync off): 103 FPS baseline -> 297 FPS.
- Sprite submission and vertex building run on all cores above
Renderer2DOptions.ParallelThreshold (default 8192). Work is sliced
into 4096-entity segments: a Friflo chunk holds a whole archetype,
so per-chunk parallelism degenerates to one thread. Segments merge
in deterministic order, preserving radix sort stability.
- Vertex buffer is ring-written with SetDataOptions.NoOverwrite
(GPU buffer 2x frame size); Discard only on wrap-around.
- Texture2DRegion precomputes UVs - four float divisions per sprite
per frame removed.
- Renderer2D exposes per-phase timings (submit/sort/build/upload/draw),
shown in the sample HUD - all further optimization is data-driven.
- Sample BounceSystem parallelized the same segmented way.
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
scene.UseUI() creates a per-scene Myra Desktop and registers
UiRenderSystem last in the draw phase (UI on top, window pixels).
GameHost now exposes itself as a Game service (Myra needs the instance;
useful for games too). Myra was picked over Gum/ImGui for the
FontStashSharp ecosystem fit, pipeline-free assets and maturity; its
internal SpriteBatch use is a documented exception to the engine rule.
Sample: on-screen HUD replaces window-title-only stats — live FPS label,
music volume slider and scene-switch buttons on both scenes.
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
SpriteBatcher now sorts with a stable LSD radix sort: equal-key sprites
keep submission order across frames (no flicker) and passes over digits
identical in all keys are skipped, making the common single-layer case
nearly free. Hot paths avoid per-sprite trig and square roots: SinCos is
skipped for unrotated sprites and the culling radius comes from the
region's precomputed diagonal.
Stress scene (100k entities, ~61k on screen, Release): 103 -> 124 FPS.
Sample now runs with VSync off to show real frame rates.
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
Switch(scene, transition) covers the old scene, swaps at full coverage
(hiding slow OnLoad), then reveals the new one. Built-in Fade and Wipe
transitions draw through TransitionRenderer (BasicEffect quad, no
SpriteBatch); custom transitions subclass Transition. Runs on unscaled
time so it works while gameplay is paused; Switch during a transition
replaces the pending target.
Sample: Tab now fades into the stress scene and wipes back.
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
