mirror of
https://github.com/andre482/O-tie.git
synced 2026-07-22 07:44:11 +00:00
69 lines
2.2 KiB
TypeScript
69 lines
2.2 KiB
TypeScript
import { describe, expect, it } from "vitest";
|
|
import {
|
|
clampZoom,
|
|
computeFit,
|
|
computeZoomAt,
|
|
MAX_ZOOM,
|
|
MIN_ZOOM,
|
|
wheelFactorFromDelta,
|
|
} from "../src/panZoom";
|
|
|
|
describe("clampZoom", () => {
|
|
it("clamps to the configured range", () => {
|
|
expect(clampZoom(0.01)).toBe(MIN_ZOOM);
|
|
expect(clampZoom(99)).toBe(MAX_ZOOM);
|
|
expect(clampZoom(1)).toBe(1);
|
|
});
|
|
});
|
|
|
|
describe("wheelFactorFromDelta", () => {
|
|
it("zooms in for negative delta and out for positive delta", () => {
|
|
expect(wheelFactorFromDelta(-100, false)).toBeGreaterThan(1);
|
|
expect(wheelFactorFromDelta(100, false)).toBeLessThan(1);
|
|
});
|
|
|
|
it("caps the per-notch step", () => {
|
|
expect(wheelFactorFromDelta(-100000, false)).toBeLessThanOrEqual(1.06);
|
|
expect(wheelFactorFromDelta(100000, true)).toBeGreaterThanOrEqual(1 / 1.08);
|
|
});
|
|
});
|
|
|
|
describe("computeZoomAt", () => {
|
|
it("keeps the point under the cursor fixed", () => {
|
|
const view = { zoom: 1, panX: 0, panY: 0 };
|
|
const next = computeZoomAt(view, 200, 100, 2)!;
|
|
expect(next.zoom).toBe(2);
|
|
// World point under (200,100) before zoom: (200,100). After zoom it must map back to (200,100).
|
|
const worldX = (200 - next.panX) / next.zoom;
|
|
const worldY = (100 - next.panY) / next.zoom;
|
|
expect(worldX).toBeCloseTo(200, 5);
|
|
expect(worldY).toBeCloseTo(100, 5);
|
|
});
|
|
|
|
it("returns null when clamped zoom does not change", () => {
|
|
const view = { zoom: MAX_ZOOM, panX: 0, panY: 0 };
|
|
expect(computeZoomAt(view, 0, 0, 2)).toBeNull();
|
|
});
|
|
});
|
|
|
|
describe("computeFit", () => {
|
|
it("centers the diagram within the viewport", () => {
|
|
const fit = computeFit(400, 200, 1000, 600, 40);
|
|
expect(fit.zoom).toBeGreaterThan(0);
|
|
const renderedW = 400 * fit.zoom;
|
|
const renderedH = 200 * fit.zoom;
|
|
expect(fit.panX).toBeCloseTo((1000 - renderedW) / 2, 5);
|
|
expect(fit.panY).toBeCloseTo((600 - renderedH) / 2, 5);
|
|
});
|
|
|
|
it("zooms out enough for large diagrams to fit inside the viewport", () => {
|
|
const viewportW = 800;
|
|
const viewportH = 600;
|
|
const padding = 40;
|
|
const fit = computeFit(5000, 3000, viewportW, viewportH, padding);
|
|
const renderedW = 5000 * fit.zoom;
|
|
const renderedH = 3000 * fit.zoom;
|
|
expect(renderedW).toBeLessThanOrEqual(viewportW - padding * 2 + 0.01);
|
|
expect(renderedH).toBeLessThanOrEqual(viewportH - padding * 2 + 0.01);
|
|
});
|
|
});
|