[Proc Gen] HeightMap - Threshold operations #197

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opened 2026-01-12 00:07:54 +00:00 by john · 0 comments

john commented

2026-01-12 00:07:54 +00:00

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Parent Issue: #192

Overview

Add threshold operations that return new HeightMap objects, preserving the original.

Specification

def threshold(self, range: tuple[float, float]) -> HeightMap

Return new HeightMap with original values where in range, 0.0 elsewhere.

def threshold_binary(self, range: tuple[float, float], value: float = 1.0) -> HeightMap

Return new HeightMap with value where in range, 0.0 elsewhere.

def inverse(self) -> HeightMap

Return new HeightMap with (1.0 - value) for each cell.

Implementation Notes

These create NEW HeightMaps (unlike scalar/combination ops which mutate)
threshold preserves original values for gradient operations (ColorLayer lerp)
threshold_binary is for pure masking
Range is inclusive: min <= value <= max

Acceptance Criteria

threshold returns new HeightMap, original unchanged
Values in range are preserved, values outside become 0.0
threshold_binary sets uniform value in range
inverse correctly inverts all values
Unit tests verify immutability of original

**Parent Issue:** #192 ## Overview Add threshold operations that return **new** HeightMap objects, preserving the original. ## Specification ```python def threshold(self, range: tuple[float, float]) -> HeightMap ``` Return new HeightMap with original values where in range, 0.0 elsewhere. ```python def threshold_binary(self, range: tuple[float, float], value: float = 1.0) -> HeightMap ``` Return new HeightMap with `value` where in range, 0.0 elsewhere. ```python def inverse(self) -> HeightMap ``` Return new HeightMap with `(1.0 - value)` for each cell. ## Implementation Notes - These create NEW HeightMaps (unlike scalar/combination ops which mutate) - `threshold` preserves original values for gradient operations (ColorLayer lerp) - `threshold_binary` is for pure masking - Range is inclusive: `min <= value <= max` ## Acceptance Criteria - [ ] `threshold` returns new HeightMap, original unchanged - [ ] Values in range are preserved, values outside become 0.0 - [ ] `threshold_binary` sets uniform value in range - [ ] `inverse` correctly inverts all values - [ ] Unit tests verify immutability of original