PQS Main – Optimised With Fast Blend

Shader: Terrain/PQS/PQS Main - Optimised With Fast Blend · materialType = OptimizedFastBlend

The PQS Material { } drives the shader that paints a body's near-surface terrain — the real, subdivided quad-sphere you see from low orbit down to the ground. This is the counterpart to the ScaledVersion materials, which paint only the distant low-LOD sphere; the PQS material takes over as the camera descends and the two are cross-faded across the fadeStart / fadeEnd altitudes. Terrain/PQS/PQS Main - Optimised With Fast Blend is the lightest member of the "PQS Main" family.

Like the rest of the family it builds the surface procedurally and world-space triplanar — projecting tiling textures down the three world axes and blending them by the surface normal, so there are no UV seams. It blends three textures by elevation, layers a separate texture on steep slopes, crossfades between a fine and a coarse tiling by camera distance, and (on bodies with an atmosphere) folds in aerial-perspective haze and underwater fog.

This variant combines two economies. Like Optimized, only the mid elevation band carries a normal map (the low and high bands are flat-shaded), giving a lighter texture budget. And like MainFastBlend it uses the 1.8 "Fast Blend" path and drops the inline Gradient option for the fog ramp. Stock Kerbin falls back to this kind of build at the lowest terrain-detail settings. For per-band normal maps with the same fast blend, see MainFastBlend; for the pre-1.8 equivalent of this cut-down build, see Optimized.

We shall first see how to enable the material, then how the shader assembles the surface, and finally discuss each group of properties in turn.

Enabling

Select the material by setting materialType = OptimizedFastBlend in the PQS { } node. The Material { } node then accepts the properties listed below.

cfg

PQS
{
    materialType = OptimizedFastBlend
    Material
    {
        // Colour grading of the per-vertex colour map
        saturation = 1
        contrast   = 1
        tintColor  = 1, 1, 1, 0

        // How strongly the textures show, and the near/far crossfade distance
        powerNear      = 0.5
        powerFar       = 0.5
        groundTexStart = 2000
        groundTexEnd   = 10000

        // Elevation bands (only the mid band takes a normal map)
        lowTex          = MyMod/PluginData/sand_color.dds
        lowNearTiling   = 1000
        lowMultiFactor  = 10

        midTex          = MyMod/PluginData/rock_color.dds
        midBumpMap      = MyMod/PluginData/rock_normal.dds
        midNearTiling   = 1000
        midMultiFactor  = 10

        highTex         = MyMod/PluginData/snow_color.dds
        highNearTiling  = 1000
        highMultiFactor = 10

        // Where each band fades to the next (on normalised vertex elevation)
        lowStart  = 0
        lowEnd    = 0.3
        highStart = 0.8
        highEnd   = 1

        // Steep-slope overlay
        steepTex      = MyMod/PluginData/cliff_color.dds
        steepBumpMap  = MyMod/PluginData/cliff_normal.dds
        steepPower    = 1

        // Atmospheric haze and underwater fog (only on bodies with an atmosphere)
        globalDensity    = 1
        fogColorRamp     = MyMod/PluginData/fog_ramp.dds
        oceanFogDistance = 1000
    }
}

How the surface is built

The shader is a triplanar terrain surface assembled per pixel. There is no single colour map; instead a base colour, three elevation textures, a steep overlay, and fog are combined in the following order:

Per-vertex colour grading — the PQS supplies a colour per vertex (COLOR.rgb, usually from a colour map or LandControl). The shader desaturates that colour toward its luma by saturation, mixes in tintColor (whose alpha is the mix amount), and scales it by contrast. The result is the base colour that the band textures then tint.
Three elevation bands — lowTex, midTex and highTex are blended by the vertex's normalised elevation (written into COLOR.w by the PQS height build). lowStart/lowEnd set the elevation window where the low band fades up into the mid band, and highStart/highEnd the window where the mid band fades into the high band — so low covers the bottom of the height range, mid the middle, high the top.
Near/far tiling crossfade — each band is sampled at two tiling scales and crossfaded by camera distance: a fine near tiling (*NearTiling) for close-up detail and a coarse far tiling (*MultiFactor) for the distance, blended between the groundTexStart and groundTexEnd view distances. powerNear and powerFar set how strongly the near and far textures show. Because the triplanar coordinates are world position scaled by 10⁻⁵, the tiling numbers are large (the defaults are 1000 near, 10 far).
Texture vs. flat colour — the blended band texture does not replace the base colour, it modulates it: the final albedo is lerp(baseColour, baseColour × bandTexture, texMix), where texMix is driven by powerNear/powerFar and the near/far mix. Where it falls to zero — far away, or with both powers at 0 — you see the flat graded colour map; where it is high you see fully textured terrain.
Steep-slope overlay — steepTex and steepBumpMap are blended over the result on steep terrain. The per-vertex steepness is multiplied by steepPower and clamped, so higher steepPower makes the cliff texture reach onto gentler slopes. The overlay has its own distance fade between steepTexStart and steepTexEnd, and its own steepNearTiling / steepTiling.
Normal mapping — as in the Optimized shader, only the mid band (midBumpMap) and the steep overlay (steepBumpMap) carry normal maps; the low and high bands are flat-shaded by the geometric mesh normal. The blended normal is transformed into world space through the mesh's tangent frame, and the surface is lit with a plain diffuse (Lambert) term plus spherical-harmonic ambient — there is no specular highlight.
Aerial-perspective & ocean fog — on a body with an atmosphere, a distance haze is mixed in last. Its colour is read from fogColorRamp indexed by the sun angle, and its strength grows with distance and globalDensity. A second, underwater ocean fog term reads the same ramp at a different row and fades over the oceanFogDistance. On an airless body the whole fog stage is compiled out and these properties do nothing.

The triplanar projection means the band textures need no UV mapping on the mesh, but the normal mapping still needs mesh tangents, which the PQS quad-sphere provides. Because the colour, elevation and slope all come from the PQS build, the final look depends as much on your PQSMods (height, colour, LandControl) as on the textures set here.

Properties

The properties fall into five groups, which we shall take in turn:

Colour grading — how the per-vertex colour map is processed before texturing.
Texture blend & distance — the near/far strengths and the crossfade distances.
Elevation bands — the three height textures (only the mid band normal-mapped) and their transition windows.
Steep-slope overlay — the cliff texture for steep terrain.
Fog & opacity — the atmospheric haze ramp, ocean-fog distance and the PQS fade scalar.

Colour grading

Property	Format	Description
`saturation`	Decimal	Saturation of the per-vertex colour map: `0` collapses it to greyscale (luma), `1` leaves it unchanged, higher oversaturates. Default 1.
`contrast`	Decimal	Contrast multiplier applied to the graded colour. Default 1.
`tintColor`	Color	A tint mixed into the base colour; the alpha is the mix amount (0 = no tint). Default (1, 1, 1, 0) — i.e. no tint.

Texture blend & distance

Property	Format	Description
`powerNear`	Decimal	Strength of the fine near texture tier. Drops the textures out toward the flat colour map as it approaches 0. Default 0.5.
`powerFar`	Decimal	Strength of the coarse far texture tier. Default 0.5.
`groundTexStart`	Decimal	View distance (m) at which the near→far tiling crossfade begins. Default 2000.
`groundTexEnd`	Decimal	View distance (m) at which only the far tiling remains. Default 10000.

Elevation bands

Each band has an albedo texture with near/far tiling; only the mid band additionally carries a normal map (with a single tiling). The band weights come from the vertex elevation and the four transition values at the end of the table.

Property	Format	Description
`lowTex`	File Path	Albedo for the low elevation band. Triplanar, world-tiled. Default "white".
`lowTexScale` / `lowTexOffset`	Vector2	Tiling and offset of `lowTex`.
`lowNearTiling`	Decimal	World tiling of the low albedo at the near tier. Default 1000.
`lowMultiFactor`	Decimal	World tiling of the low albedo at the far tier. Default 10.
`midTex`	File Path	Albedo for the mid elevation band. Default "white".
`midTexScale` / `midTexOffset`	Vector2	Tiling and offset of `midTex`.
`midBumpMap`	File Path	DXT5nm normal map for the mid band — the only band that has one. Default "bump" (flat).
`midBumpMapScale` / `midBumpMapOffset`	Vector2	Tiling and offset of `midBumpMap`.
`midNearTiling`	Decimal	World tiling of the mid albedo at the near tier. Default 1000.
`midMultiFactor`	Decimal	World tiling of the mid albedo at the far tier. Default 10.
`midBumpNearTiling`	Decimal	World tiling of the mid normal map. Default 1.
`highTex`	File Path	Albedo for the high elevation band. Default "white".
`highTexScale` / `highTexOffset`	Vector2	Tiling and offset of `highTex`.
`highNearTiling`	Decimal	World tiling of the high albedo at the near tier. Default 1000.
`highMultiFactor`	Decimal	World tiling of the high albedo at the far tier. Default 10.
`lowStart`	Decimal	Elevation (normalised 0–1) at which the low band begins fading into the mid band. Default 0.
`lowEnd`	Decimal	Elevation at which the low band has fully given way to the mid band. Default 0.3.
`highStart`	Decimal	Elevation at which the mid band begins fading into the high band. Default 0.8.
`highEnd`	Decimal	Elevation at which the high band fully takes over. Default 1.

Steep-slope overlay

Property	Format	Description
`steepTex`	File Path	Albedo blended over steep slopes (cliffs). Default "white".
`steepTexScale` / `steepTexOffset`	Vector2	Tiling and offset of `steepTex`.
`steepBumpMap`	File Path	DXT5nm normal map for the steep overlay. Default "bump".
`steepBumpMapScale` / `steepBumpMapOffset`	Vector2	Tiling and offset of `steepBumpMap`.
`steepPower`	Decimal	Multiplier on the vertex steepness before it is clamped to the overlay weight. Higher values push the steep texture onto gentler slopes; 0 disables it. Default 1.
`steepTexStart`	Decimal	View distance (m) at which the steep overlay's near→far tiling fade begins. Default 20000.
`steepTexEnd`	Decimal	View distance (m) at which the steep overlay reaches its far tiling. Default 30000.
`steepNearTiling`	Decimal	World tiling of the steep overlay at the near tier. Default 1.
`steepTiling`	Decimal	World tiling of the steep overlay at the far tier. Default 1.

Fog & opacity

Property	Format	Description
`globalDensity`	Decimal	Density multiplier for the aerial-perspective haze. Only has an effect on bodies with an atmosphere; higher values thicken the distance fog. Default 1.
`fogColorRamp`	File Path	1-D colour ramp for the fog. The aerial haze is read from it indexed by the sun angle (so the fog can be tinted differently toward and away from the sun); a second row supplies the underwater ocean-fog colour. Default "white".
`fogColorRampScale` / `fogColorRampOffset`	Vector2	Tiling and offset of the fog ramp.
`oceanFogDistance`	Decimal	Falloff distance (m) of the underwater ocean fog — the distance over which the surface fades into the ocean-fog colour when seen from below the waterline. Default 1000.
`planetOpacity`	Decimal	Opacity of the PQS material, used by KSP to fade the terrain against the scaled-space sphere across the `fadeStart`/`fadeEnd` transition. Normally left at 1. Default 1.

Notes

These are the body's near-surface terrain materials. The body simultaneously has a ScaledVersion material for the distant sphere; KSP cross-fades between the two across the fadeStart / fadeEnd altitudes, so the two should be tuned to match where they meet.
This is the leanest of the family: only the mid band is normal-mapped, and (being a "Fast Blend" build) it does not offer the inline Gradient form of the fog ramp. If the low or high bands need surface relief, use MainFastBlend.
The textures are world-space triplanar, so they need no UVs and the tiling values are in world units scaled by 10⁻⁵ (hence the large defaults). The shader still requires mesh tangents for its normal mapping, which the PQS quad-sphere provides.
The band colour, the per-vertex elevation that drives the band blend, and the slope that drives the steep overlay all come from the PQS build — your height, colour and LandControl mods shape the input this shader paints.
The fog stage (globalDensity, fogColorRamp, oceanFogDistance) is only compiled in for bodies with an atmosphere; on an airless body it is removed entirely and those properties have no effect.
Several shader inputs are driven by KSP at runtime and are not config properties: a floating-origin offset that keeps the world-space triplanar coordinates stable as the game shifts the origin around the craft, and the sun direction, camera altitude and viewer air density used by the fog.
The surface is lit with a diffuse (Lambert) term only — there is no specular response on this shader.
materialType = OptimizedFastBlend is also accepted under its older alias AtmosphericOptimizedFastBlend, which you may see in existing configs; the two select the same shader.

PQS Main – Optimised With Fast Blend ​

Enabling ​

How the surface is built ​

Properties ​

Colour grading ​

Texture blend & distance ​

Elevation bands ​

Steep-slope overlay ​

Fog & opacity ​

Notes ​