Add aspect-preserving opaque image fitting

2026-11-07 17:12:00 +01:00
parent bb90b2c060
commit 2620a17c64
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+# Opaque image fitting
+
+`ImageScaler.fitOpaque(source, maxWidth, maxHeight, background)` returns an
+independent RGB BufferedImage. It fits within positive bounds without enlargement,
+keeps aspect ratio to the nearest pixel (minimum one pixel per dimension), and
+composites transparent pixels onto the supplied opaque AWT Color. Bilinear
+interpolation is used. The source is unchanged and graphics resources are released.
+
+This operation is independent of file format and wire encoding. Callers own image
+decoding, any source subsampling, and target quantization. Existing PNG scaling
+methods retain their original behavior.
+
+`ImageScalerTest` verifies fitting, no enlargement, transparent/partial-alpha
+composition, narrow images, source preservation, and invalid bounds.