Draws a rectangle using the current pen/outline color for the border and brush/fill color for the insides
The outer lines, inclusive of x = 0, y = 0, x = width - 1, and y = height - 1 are drawn with the outlineColor
The rest of the pixels are drawn with the fillColor. If fillColor is transparent, those pixels are not drawn.
The D Programming Language's Unofficial Docs
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Draws a rectangle using the current pen/outline color for the border and brush/fill color for the insides The outer lines, inclusive of x = 0, y = 0, x = width - 1, and y = height - 1 are drawn with the outlineColor The rest of the pixels are drawn with the fillColor. If fillColor is transparent, those pixels are not drawn.