30 lines
792 B
Dart
30 lines
792 B
Dart
import 'dart:math' as math;
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import 'dart:ui';
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/// Deterministic serpentine layout for the journey map. Stage 0 is at the
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/// bottom; the path snakes upward. Works for any stage count.
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class MapLayout {
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const MapLayout({
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required this.width,
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this.nodeSpacing = 108,
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this.topPadding = 140,
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this.bottomPadding = 150,
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});
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final double width;
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final double nodeSpacing;
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final double topPadding;
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final double bottomPadding;
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double get amplitude => width * 0.26;
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double heightFor(int count) =>
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topPadding + bottomPadding + (count - 1) * nodeSpacing;
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Offset nodeCenter(int index, int count) {
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final y = heightFor(count) - bottomPadding - index * nodeSpacing;
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final x = width / 2 + amplitude * math.sin(index * 1.05);
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return Offset(x, y);
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}
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}
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