layers/ground.h
| Line | Branch | Exec | Source |
|---|---|---|---|
| 1 | /// @file | ||
| 2 | /// @brief The terrain beneath a layer, readable at any point. | ||
| 3 | #pragma once | ||
| 4 | |||
| 5 | #include "terraingen/util/geometry.h" | ||
| 6 | |||
| 7 | #include <cstddef> | ||
| 8 | #include <functional> | ||
| 9 | #include <span> | ||
| 10 | |||
| 11 | namespace terraingen { | ||
| 12 | |||
| 13 | /// Heights of the ground at world positions, NaN where there is none; thread-safe. | ||
| 14 | using HeightSampler = std::function<float(double x, double y)>; | ||
| 15 | |||
| 16 | /// The terrain beneath a layer (its source and the layers before it), readable anywhere. | ||
| 17 | /// | ||
| 18 | /// Layers that depend on the shape of the ground, such as craters cut to a datum, read it here | ||
| 19 | /// rather than from cells they changed, so they agree on every grid, tile and point. | ||
| 20 | /// Implementations must be deterministic and thread-safe. | ||
| 21 | class Ground { | ||
| 22 | public: | ||
| 23 | 46637926 | virtual ~Ground() = default; | |
| 24 | |||
| 25 | /// The ground's height at world (x, y), or NaN where there is no data. | ||
| 26 | /// @param spacing Sample spacing in world units. | ||
| 27 | virtual float HeightAt(double x, double y, double spacing) const = 0; | ||
| 28 | |||
| 29 | /// `HeightAt` at each of `points`, into `heights` of the same size; implementations may read | ||
| 30 | /// them all in one pass, to the same values. | ||
| 31 | 676 | virtual void HeightsAt(std::span<const Vec2d> points, std::span<float> heights, | |
| 32 | double spacing) const { | ||
| 33 | 381187 | for (std::size_t i = 0; i < points.size(); ++i) { | |
| 34 | 380511 | heights[i] = HeightAt(points[i].x, points[i].y, spacing); | |
| 35 | } | ||
| 36 | 676 | } | |
| 37 | |||
| 38 | /// A sampler reading `HeightAt` at a fixed spacing; `*this` must outlive it. | ||
| 39 | 220550 | HeightSampler Sampler(double spacing) const { | |
| 40 | 1497442 | return [this, spacing](double x, double y) { return HeightAt(x, y, spacing); }; | |
| 41 | } | ||
| 42 | }; | ||
| 43 | |||
| 44 | } // namespace terraingen | ||
| 45 |