opacity

rpic extension. opacity sets the fill opacity of an object — 0 is transparent, 1 opaque. The classic use: overlapping regions that should both stay readable.

.PS
circle rad 0.42 shaded "gold" opacity 0.55
circle rad 0.42 shaded "steelblue" opacity 0.55 at last circle + (0.45, 0)
"A" at 1st circle - (0.14, 0); "B" at last circle + (0.14, 0)
.PE

Rules

• Applies to the fill only (SVG fill-opacity); the stroke stays crisp. Whole-object and stroke opacity are possible future increments.
• Composes with every fill: fill, shaded, gradient, hatch backgrounds.
• A block’s opacity multiplies into its members’ fills.
• Default is fully opaque — untouched input renders byte-for-byte classic.

.PS
box wid 1.1 ht 0.6 gradient "crimson" "navy" opacity 0.4 "readable"
.PE