raster.test.ts

1	import { readFileSync } from 'node:fs'
2	import { describe, expect, it } from 'vitest'
3	import {
4	RASTER_HEIGHT, RASTER_MAX_HEIGHT_M, RASTER_MIN_HEIGHT_M, RASTER_WIDTH,
5	isSurface, rasterSet,
6	} from '../src/views/raster.js'
7	import { MAP_CUT_WITHOUT_SLATS } from '../src/canon/geometry.js'
8
9	const geo = JSON.parse(readFileSync('content/geography.json', 'utf8')) as {
10	render: {
11	gridWidth: number; gridHeight: number
12	minHeightM: number; maxHeightM: number; mapThetaOrigin: number
13	}
14	}
15
16	/**
17	* The interior view displaces its shell by the height raster and paints it with the
18	* colour raster. Both are read as fractions of numbers the app cannot see, so if
19	* the generator's idea of them ever drifts, the terrain moves or flattens with no
20	* error anywhere.
21	*/
22	describe('raster metadata matches the generator', () => {
23	it('agrees on the grid', () => {
24	expect(geo.render.gridWidth).toBe(RASTER_WIDTH)
25	expect(geo.render.gridHeight).toBe(RASTER_HEIGHT)
26	})
27
28	it('agrees on what black and white mean in the height map', () => {
29	expect(geo.render.minHeightM).toBe(RASTER_MIN_HEIGHT_M)
30	expect(geo.render.maxHeightM).toBe(RASTER_MAX_HEIGHT_M)
31	})
32
33	/**
34	* The range is declared rather than fitted so the raster keeps its meaning as the
35	* geography is edited. That only works if it actually contains the terrain, so
36	* check it still does — the generator warns, but nobody watches a build log.
37	*/
38	it('still covers the terrain it is meant to cover', () => {
39	// The extremes the generator last measured. These are a second line of defence
40	// and a weak one — they are numbers written down when they were true, not the
41	// terrain that came out of the most recent run, so they cannot notice the
42	// geography growing past them. `npm run terrain` now exits non-zero when a
43	// pixel is clamped, which is the check that actually holds.
44	expect(RASTER_MIN_HEIGHT_M).toBeLessThanOrEqual(-521)
45	expect(RASTER_MAX_HEIGHT_M).toBeGreaterThanOrEqual(4381)
46	})
47
48	it('agrees on where the map is cut', () => {
49	expect(geo.render.mapThetaOrigin).toBeCloseTo(MAP_CUT_WITHOUT_SLATS, 6)
50	})
51	})
52
53	/**
54	* The Cascadia surface is a second pair of rasters on the same cylinder (D-055).
55	* It only works because it shares canon's grid and height window: the interior
56	* view bakes that window into its GLSL as literals, so a surface that quietly
57	* declared its own would displace its ground by the wrong scale — silently, which
58	* is D-024's failure mode exactly. tools/cascadia.mjs cannot import this module,
59	* so read the constants back out of it and hold it to them.
60	*/
61	describe('every surface shares one height window', () => {
62	const src = readFileSync('tools/cascadia.mjs', 'utf8')
63	const constant = (name: string): number => {
64	// The declarations carry trailing comments, so match the number, not the line.
65	const m = new RegExp(`^const ${name} = (-?\\d+)\\b`, 'm').exec(src)
66	if (!m) throw new Error(`tools/cascadia.mjs no longer declares ${name}`)
67	return Number(m[1])
68	}
69
70	it('cascadia borrows canon\u2019s range rather than declaring its own', () => {
71	expect(constant('HEIGHT_MIN_M')).toBe(RASTER_MIN_HEIGHT_M)
72	expect(constant('HEIGHT_MAX_M')).toBe(RASTER_MAX_HEIGHT_M)
73	})
74
75	it('cascadia is sampled onto canon\u2019s grid', () => {
76	expect(constant('GRID_W')).toBe(RASTER_WIDTH)
77	expect(constant('GRID_H')).toBe(RASTER_HEIGHT)
78	})
79
80	it('names a distinct pair of rasters per surface', () => {
81	expect(rasterSet('canon')).not.toEqual(rasterSet('cascadia'))
82	for (const s of ['canon', 'cascadia'] as const) {
83	expect(rasterSet(s).color).toMatch(/\.png$/)
84	expect(rasterSet(s).height).toMatch(/\.png$/)
85	}
86	})
87
88	it('rejects a surface name it does not know', () => {
89	expect(isSurface('canon')).toBe(true)
90	expect(isSurface('cascadia')).toBe(true)
91	expect(isSurface('wisconsin')).toBe(false)
92	expect(isSurface(null)).toBe(false)
93	})
94	})