MSFFogOptions

Constructs a FogOptions object with default values.

Returns whether the fog is drawn at all.

Enables or disables the fog without touching any of its values, so a toggle does not have to drive the color or the range through zero. Off means no haze anywhere - the tile content, the background plane, the terrain surface and the sky all stop fogging together.

It stops the HAZE only. HighColor, SpaceColor and StarIntensity ride on this class because Mapbox puts them on its fog property, but they are the sky’s: turning the fog off leaves the dusk sky and the stars exactly as they were. Unlike every other property, this one is ANDed with the style rather than overridden by it: a style cannot re-enable a fog the application switched off. Style property: “fog-enabled” (0 or 1).

Returns the fog color.

Sets the color distant terrain, rasters, geometry and 3D extrusions fade towards. The alpha channel is how opaque the fog gets at full distance, so a fully transparent color (the default) means no fog at all. Fog is what makes a long view distance look like distance rather than like a hard cut, and it is what hides the edge of the terrain when the maximum visible distance is limited. With terrain lighting on, the color is lit by the sun before it is used - haze is air, so it darkens at night and warms at a low sun. Style property: “fog-color”.

Returns where the fog starts.

Sets where the fog starts, in multiples of the camera-to-focus distance. Nothing nearer than this is fogged at all. Mapbox range[0]. Style property: “fog-range-start”.

Returns where the fog reaches full strength.

Sets where the fog reaches its full strength, in multiples of the camera-to-focus distance. A value at or below RangeStart turns the fog off. Mapbox range[1]. Style property: “fog-range-end”.

Returns the color of the upper atmosphere.

Sets the color the sky takes above the fog band - Mapbox high-color, the lit upper atmosphere. Transparent (the default) leaves the sky gradient to SkyOptions alone. Style property: “fog-high-color”.

Returns the color of the sky at the zenith, beyond the atmosphere.

Sets the color the sky reaches straight up, beyond the atmosphere - Mapbox space-color. Transparent (the default) leaves the sky gradient to SkyOptions alone. Style property: “fog-space-color”.

Returns how far up the sky the fog is blended in.

Sets how far above the horizon the fog fades out, as a Mapbox horizon-blend: the fog is scaled by exp(-3 * (sin(elevation) / blend)^2), so it is full at the horizon and essentially gone one blend above it. 1 hazes the whole sky, 0 confines the fog to the horizon itself.

The SAME factor scales the ground, where the elevation angle is negative and the factor is therefore 1 - so distant ground is fogged by distance alone, a ridge standing above the horizon takes exactly what the sky just above it takes, and the two meet with no seam at any tilt or zoom. Style property: “fog-horizon-blend”.

Returns the altitude the fog starts fading out at.

Sets the altitude, in meters above sea level, that the fog starts to fade out at - Mapbox vertical-range[0]. Below it the fog is at full strength. Together with VerticalRangeEnd this is what lets a summit stand clear of a haze filling the valley. Leaving both at 0 (the default) fogs every altitude equally. Style property: “fog-vertical-range-start”.

Returns the altitude the fog has fully faded out at.

Sets the altitude, in meters above sea level, that the fog has completely faded out at - Mapbox vertical-range[1]. A value at or below VerticalRangeStart disables the fade. Style property: “fog-vertical-range-end”.

Returns how brightly stars are drawn beyond the atmosphere.

Sets how brightly stars are drawn in the part of the sky the atmosphere has faded out of

• Mapbox star-intensity. 0 (the default) draws none. They are drawn by the built-in sky shader only, so a custom sky shader has to draw its own. Style property: “fog-star-intensity”.

Returns the custom fog fragment shader source, or an empty string if the built-in blend is used.

Replaces the WHOLE fog block - every function the SDK would have supplied - for the tile content, the background plane, the terrain surface, the vector elements and the sky alike, in 2D and in 3D. The source must define all three entry points:

vec4  applyFog(vec4 color, vec3 dir, float dist, float heightM);
vec4  skyFog(vec4 color, vec3 dir);
float fogLabelFade();

where color is the fragment’s PREMULTIPLIED color, dir is the normalized world-space view ray through it (x east, y north, z up), dist is the true distance from the camera in multiples of the camera-to-focus distance - the unit the range is in - and heightM is the fragment’s altitude in meters. skyFog is the sky’s case: at infinity, so only the direction varies. fogLabelFade is what a label’s alpha is multiplied by, so a label does not go on floating over a map the fog has already swallowed.

The uniform block below is always declared by the SDK and must NOT be redeclared:

uniform vec4 uFogColor;      // the resolved and lit fog color, rgba 0..1
uniform vec4 uFogHighColor;  // the upper atmosphere color, rgba 0..1
uniform vec4 uFogSpaceColor; // the zenith color, rgba 0..1
uniform vec4 uFogParams;     // range start, 1 / (end - start), internal -> range units, horizon blend
uniform vec4 uFogVertical;   // vertical range start and end in meters, meters per unit, camera height
uniform mat3 uFogRay;        // view ray basis, used by the SDK's own call site

These helpers are always declared too, so a custom shader can build on the SDK’s model instead of restating it - or ignore them and compute its own:

vec3  fogRayVec();                 // unnormalized world-space ray through the fragment
float fogRange(float dist);        // distance remapped to 0 at the start, 1 at the end
float fogOpacity(float t);         // the distance ramp, already scaled by the color's alpha
float fogHorizonBlend(vec3 dir);   // the angular term, 1 below the horizon
float fogVertical(float heightM);  // how much of the fog this altitude escapes

Pass an empty string to go back to the built-in blend. If the shader fails to compile, the built-in blend is used and the error is logged.

Undocumented