Outdoor Maps Changes

Outdoor maps — SilentPines Gorge + Dusk Falls

Two mission worlds promoted from 34-line placeholders to playable maps:

World	Mission	Objective	Next
GameData/Worlds/Sektor_01_SilentPines	Sektor_01_SilentPines (Sefirah 1, Terran Prime)	Objective_ClearArea — kill 5	Sektor_02_MegacityGrid
GameData/Worlds/KryoArchipel_Severny	KryoArchipel_Severny (Sefirah 2, Hydrosis Prime)	Objective_CollectRelics — collect 3	Refinery_Complex_02B

Direction was Unreal-'98 outdoor set pieces (NyLeve's Falls / a dusk cascade). Both are all-brush maps: 150 and 136 primitives, 0 errors and 0 headroom traps on worldcheck.

Why all-brush rather than a heightmap

Collision is AABB brushes only. A heightmap supplies a terrain surface (per-cell SampleHeightmapY ground clamp) but no lateral collision, so a heightmap cliff is walk-through. Dust_Ravine is the only shipped heightmap and it is nearly flat (10 units of relief over 180), which is exactly the safe role: gentle ground relief, with all real elevation from brushes. These maps skip the heightmap and build the gorge/terraces from boxes and cylinders.

Every walkable rise is 0.9, not 1.0: kStepHeight is exactly 1.0f, so a 1.0 step sits on a float comparison boundary.

The waterfall kit

# Cascade sheet (0.2 thick), 0.1 clear of the solid face it hangs on
add box <x> <y> <zmid> 0.2 <h> <d> 0 \
  texPath=GameData/Tex/Global/EFX/waterfall_streaks.png texScaleU=1.5 texScaleV=1 \
  flags=268962944 surfAlpha=0.9 panV=-0.35

268962944 = SURF_UNLIT 2048 | SURF_TRANSLUCENT 128 | SURF_TWO_SIDED 1024 | SURF_PAN_V 524288 | SURF_NO_BSP_CUTS 268435456.

• UNLIT matters: without it the sheet takes scene lighting and a dusk waterfall renders as a grey slab.
• NO_BSP_CUTS keeps the sheet cosmetic so it is not an invisible wall.
• Negative panV scrolls the texture downward (uv.y += uPan.y * uTime).
• Pools/rivers use flags=264320 (UNLIT | PAN_U | TRANSLUCENT) with surfAlpha=0.8.

SilentPines' falls also needed a rock face behind the notch (x 86.1..87.5): with the notch open to the skybox the water read as a blue panel rather than a fall.

Water textures (tools/gen_water_textures.ps1)

The repo shipped one water texture, liquid_water.png: a high-contrast blue tile pattern. On a large pool it reads as bathroom tiling, and on a cascade sheet as a flat blue panel. Two textures were generated instead (deterministic — fixed RNG seeds, so re-running rewrites identical bytes):

Texture	Size	Purpose
water_pool.png	64x64 RGB	Dark, low-contrast ripple field (mean RGB ≈ 18/40/58). Pool slabs are `UNLIT
waterfall_streaks.png	64x128 RGBA	Vertical streaks with punched transparent gaps (12.3% of pixels alpha 0, mean alpha 156).

The alpha is the whole point: Surface.fs multiplies the sampled texture's alpha by uAlpha, so transparent holes are what turn a sheet into falling water. The first version of the generator drew 150 anti-aliased lines over a 64px width and measured 84% of pixels inked — a near-solid pale panel. The script now draws 90 thin streaks and then erases 34 small rectangles with CompositingMode.SourceCopy, which is what guarantees real holes rather than low-alpha haze.

The UV trap that dominated the first art pass

OzoneLoader::BuildBox multiplies generated UVs by 16 when h >= 1.0 and 8 when thin, and the authored texScaleU/V is applied on top of that. Values in the shipped-demo range (8–14) therefore compound to hundreds of repeats on a large brush and render as moire noise. Author texScale near 1 for big surfaces. This was the single largest visual defect found by rendering the maps, and it is invisible to worldcheck.

Validation

worldcheck --headroom-all   both worlds: 0 errors, headroom traps: 0
worldcheck --asset-refs     both: no new dangling asset references, 0 case mismatches
client --shot               all captures render; every texPath loads and decodes
in-game log                 sky zone defs bind and their on_enter actions fire

One benign warning per world: multiple playerstarts; only #1 is ever used — the maps author a second playerstart for parity with the other worlds; PawnSystem::GetFirstPlayerStart only reads #1.

Sky: the seam fix

Two independent defects, both measured rather than guessed:

1. Cap band. The skybox draws top/bottom faces with a different texture (useCap) on a horizontal quad, so every wall top met an unrelated image. The band was a 50-level (day) / 24-level (dusk) tonal step.
2. Corner panels. The six quads are separate planes and the four wall quads do not agree on their V mapping. Measured at a cube corner: adjacent walls differed by 33-40 colour levels at the same screen row, and the outer panels ramped horizontally within a row while the wall facing the camera was flat. That is a per-face V offset, so no texture can fix it — a vertically symmetric texture only cancels a flip (it took the step from 41 to 33).

The fix, in three parts:

• tools/gen_sky_textures.ps1 generates horizontally periodic, vertically symmetric gradients (sky_grad_day.png, sky_grad_dusk.png): every horizontal variation is a sum of sin(2*pi*k*u) with integer k and the last column is overwritten with column 0, so corners match by construction; and colour(y) == colour(h-1-y), so a V flip is invisible.
• Sky.fs samples V from WORLD ELEVATION, not from the quad's texcoord: elevV = clamp(dirW.y * 0.5 + 0.5, 0, 1). Elevation is a property of the view ray, so every quad — walls and cap alike — agrees by construction. This is what actually removed the corners.
• Both worlds pass the same gradient as cap and sides (levelinfo <grad> <grad>); with a separate cap image the elevation V made the cap's flat zenith meet the walls' 91%-to-zenith row, leaving a faint trapezoid.

Measured on the same cameras (largest adjacent-pixel step in the sky):

	before	after
SilentPines, seam column x=215 at rows 20 / 60 / 120	33 / 28 / 20	1 / 1 / 1
KryoArchipel, seam column x=215	40 / 36 / 25	5 / 4 / 3
SilentPines, cap band	50 levels	1
KryoArchipel, cap band	24 levels	1
EngineTest (legacy panorama), hard straight band	16.06 lum	2.13 lum

Residuals: a ≤5-level step at the U face boundary (each face still supplies its own fragTexCoord.x), and a faint trapezoid when looking steeply up at the zenith. Both are shading-level, not the hard panels of before.

Behaviour change to know about: because V now tracks elevation, a wall samples only V ≥ 0.5. Legacy panorama skies therefore show only the upper half of their image on the walls — sky_noon.png / sky_day.png now display their top half, which also moved that art's own baked 26-31 level wrap seam onto a constant elevation contour. Legacy worlds measured better (EngineTest's band fell 16.06 → 2.13), but the change is visible and is not confined to the two outdoor maps.

Known visual limitations (engine-level, not content bugs)

1. Sky box cube seams - fixed (see above). The hard panels, the cap band and the corner tonals are gone. What remains is a <=5-level step at each U face boundary (each face still supplies its own fragTexCoord.x) and a faint trapezoid when looking steeply up at the zenith.
2. Water is still a scrolling texture, not a simulation. No foam sheet, refraction or depth term exists; waterfall_streaks.png, water_pool.png and foam.png are paint, and the motion comes from the pan. Foam now reads at the cascade impacts (an impact band, a 3.4x faster churn wall, and shore strips), but it is 1998, not 2004.
3. Outdoor scale reads arena-like. With no terrain and AABB-only collision, a wide valley is a floor plate between tall boxes. Dusk Falls was tightened for this reason (depth 168 -> 102, pools 27x24/44x24/38x28 -> 20x18/26x18/26x22, aqueduct narrowed, seven ruin fragments added); the terraces now have landmarks and a horizon instead of reading as empty plains.
4. No waterfall audio loop. Script play_sound is one-shot; the keyed loop API is stat-driven only. The falls are silent.

Reusable lessons

• Boundary treatment decides whether an outdoor map reads as outdoors: a 44-unit painted ring at the map bounds turns every sightline into a courtyard wall. A ~12-unit rock ridge leaves the sky visible and still stops the player walking off the world.
• Place the spawn at the edge of a height, not in the middle of a plateau, or the first frame is a floor.
• Box arg order is x y z w h d rot: the 5th number is vertical size, the 6th is Y depth.