VIRUXE/samp-house-shells

samp-house-shells

Making SA-MP's enterable house shells look like they belong in San Andreas.

The SA-MP client ships a set of house models in SAMP\SAMP.img: an exterior that reuses a vanilla house's textures plus a separate interior, for LS, SF and LV.

Servers use them in place of the solid vanilla houses so that players can walk in. Next to the vanilla city they look out of place. This repo holds the tooling, the reworked models and before/after screenshots. The goal is replacement DFF files that any SA-MP or MTA:SA server can use as a drop-in.

Status

Before and after

All 12 houses, original next to reworked, rendered in Blender →

Baked interior lighting (#2)

The original *int models have no prelight at all (geometry flags 0x10036, no prelit bit 0x08, no night colours), so the game lights them uniformly and they glow at midnight. They now carry day and night vertex colours baked from Cycles ambient occlusion, with the exterior loaded as an occluder. Each model's material colour goes from grey 127 to white, because SA multiplies texture × prelight × material colour.

In game (MTA:SA client, same house, the baked model loaded via engineReplaceModel):

Glazed windows (#3)

The shells ship with open window holes. Maps fill each one with SA-MP's 19466 window001: 1,643 objects in the Scavenge & Survive houses alone. That model has no prelight and a grey 127 material, so every pane glowed white at night, and its texture was a flat 16×16 grey at 85% alpha.

• Each exterior now has its own windows. Every opening gets a lined reveal, a sill, glass set into the wall, a frame that stands out of it and, behind it, curtains, a blind or nothing. The frame follows the window texture in the house's vanilla TXD: white sashes in SF, weathered wood in Ganton, louvres, security bars, and so on (see the houses). Everything else in the DFF is left exactly as SA-MP shipped it. With these models a server can stop placing window001 in the houses.
• The look follows vanilla's see-through glass. In the Wang Cars showroom (carshowwin_SFSX) and the SF Ammu-Nation (ammuwindows_SFS), glass is a white-material alpha texture with dark prelight (about 35 by day). It reads as glass with the room behind it, never as a grey board; light, lit-from-inside windows come only from bright night colours. The exteriors use vanilla TXDs, which have no glass texture, so the panes are untextured: alpha 170, prelight graded from about 30 at the bottom to 60 at the top like a sky reflection, a diagonal reflection band, and dark at night.

• window001 is fixed as well, for maps that keep it. It gets day/night prelight and a white material, and lsmall_window01 in lsmall_shops.txd becomes a 64×64 glass texture: a sky-to-street gradient with two reflection streaks, at 59% alpha so the room shows through. 19325 lsmall_window01 (shop glass) shares that texture.

How the openings are found:

1. tools/window_seeds.py takes every window001 near a shell into that shell's frame, plus every door object. Offsets that recur in at least half of the instances become seeds (data/window_seeds.json).
2. tools/glaze_shells.py adds seeds of its own. Maps glaze only some holes: lshouse3 gets one, and lvhouse4's seeds sit outside the model. The script sweeps each exterior with horizontal rays from 8 directions, groups the hits into wall planes, and takes every enclosed gap in a plane as a seed.
3. Each seed is fitted: rays are cast through the wall on a 4 cm grid around it, and the open region connected to the seed is the opening. Openings that leak past ±3 m are dropped. Scanned openings are also dropped when they:
   • hold a map door object (an entrance),
   • are not fully rectangular (an arched doorway), or
   • are over 2.4 m tall (a garage).
4. The fitted openings go to data/windows.json (each tagged map or scan), and tools/add_panes.py writes the panes.

ariane/tour.py flies the editor round one instance of each shell and captures it from two corners, which is how the missing panes were spotted.

The "after" shots hide every window001 (apply-removals.ps1 -WithoutPanes), so the glass you see is the shells' own.

All shots are viewport captures from Ariane at weather 1, taken by ariane/shots.ps1 from fixed cameras, so before and after line up exactly. The placements are a real server's: the house maps of Scavenge & Survive (CC BY-SA 4.0), which also remove the vanilla houses underneath.

Layout

Workflow

# bake (headless, ~1 min for all 12)
& 'C:\Program Files\Blender Foundation\Blender 5.2\blender.exe' --background --factory-startup --python tools/bake_interiors.py -- models/original models/baked
# glaze the exteriors and rework window001 (DragonFF checkout for gtaLib)
python -I tools/window_seeds.py <game copy>\scavenge\scavenge.ipl data/window_seeds.json
& 'C:\Program Files\Blender Foundation\Blender 5.2\blender.exe' --background --factory-startup --python tools/glaze_shells.py -- models/original data/window_seeds.json data/windows.json
python -I tools/add_panes.py <DragonFF> models/original data/windows.json models/baked
python -I tools/rework_window.py <DragonFF> models/original models/baked
# render every house for docs/houses.md (renders in work/renders)
& 'C:\Program Files\Blender Foundation\Blender 5.2\blender.exe' --background --factory-startup --python tools/render_houses.py
python -I tools/gallery.py
# look at one in Blender (original left, baked right; Scene properties > Custom Properties > night)
& 'C:\Program Files\Blender Foundation\Blender 5.2\blender.exe' --python tools/view_house.py -- lshouse1
# see it in the world, then capture and compare
pwsh ariane/use-shells.ps1 baked        # or: original; baked also hides the maps' window001
pwsh ariane/shots.ps1 after             # or: before; optional name filter, e.g. '*-interior'
python -I tools/compare.py

DragonFF notes. gtaLib reads the BinMesh into a plain list (extensions["mat_split"]) that its writer cannot serialise. The gtaLib tools move those triangles, which carry the real material ids, into geometry.triangles and let the writer rebuild the BinMesh. SA-MP's shells keep their material ids only in the BinMesh PLG; the triangle list says material 0 everywhere. Import with read_mat_split=True, or every face gets the first texture. Import with remove_doubles=False, or overlapping faces are merged away. The bake checks that each output's BinMesh matches the original's.

Tools

• Ariane Agent Alpha 1 (map editor with a CLI/MCP agent interface), on a dedicated copy of the game so it never writes to the install you play on.
• GTA Scout to find vanilla textures and props that fit.
• Blender 5.2 with DragonFF (latest master; DFF/TXD import and export, day/night vertex colours) and blender-mcp.

Setup

1. Copy the game (with its SAMP folder) somewhere else, e.g. D:\Games\GTA San Andreas\ariane-sa, and put ariane.exe and fonts\ from the Agent Alpha bundle next to gta_sa.exe.

2. In the copy's data\gta.dat, add the following lines. Put the IMG lines after the existing IMG lines, the IDE lines after the last IDE line, and the IPL line at the end. Later IMG lines override entries of the same name, which is how SHELLS.IMG swaps in the reworked models; ariane/use-shells.ps1 manages that line.

   IMG SAMP\SAMP.IMG
   IMG SAMP\SAMPCOL.IMG
   IMG SAMP\CUSTOM.IMG
   IMG SHELLS\SHELLS.IMG
   IDE SAMP\SAMP.IDE
   IDE SAMP\CUSTOM.IDE
   IPL SCAVENGE\SCAVENGE.IPL
   

3. Generate the placements and run the editor:

   python -I tools/make_ipl.py <scavengesurvive-mta checkout> <game copy> <game copy>\scavenge
   pwsh ariane/start.ps1              # editor on port 48731, token in %LOCALAPPDATA%\ariane-agent\token
   pwsh ariane/apply-removals.ps1     # replays the maps' RemoveBuildingForPlayer list as a scratch session
                                      # (-WithoutPanes also hides window001; takes seconds)
   

   make_ipl.py reads the map data that scavengesurvive-mta generates from the upstream .map files. It writes a text IPL plus the removal list. Map-wide removals are expanded into one entry per vanilla instance, because Ariane caps suppress-world-models at a 250 m radius.

4. For tools/view_house.py, extract the vanilla TXDs it shows into the ignored work/txd/ folder: python -I tools/img.py extract <game copy>\models\gta3.img work/txd ganghouse1_lax.txd comedhos1_la.txd glenphouse_lax.txd boxhses_sfsx.txd vegashse2.txd vegashse3.txd vegashse4.txd vegashse6.txd, plus copy models\original\all_walls.txd work\txd\.

Licence

The scripts, screenshots and our edits are released into the public domain under the Unlicense. The model files come from the SA-MP client. Vanilla GTA San Andreas files are never committed (work/ is ignored).