▼Pict:   Functional Pictures
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hyperlinkize
scale-color
color-series
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13 Miscellaneous

procedure

(hyperlinkize pict) → pict?

  pict : pict-convertible?
Adds an underline and blue color. The pict’s height and descent are extended.

Example:
> (hyperlinkize (text "Help me I'm trapped in this documentation"
                      null 15))

image

procedure

(scale-color factor color) → (is-a?/c color%)

  factor : real?
  color : (or/c string (is-a?/c color%))
Scales a color, making it brighter or darker. If the factor is less than 1, the color is darkened by multiplying the RGB components by the factor. If the factor is greater than 1, the color is lightened by dividing the gap between the RGB components and 255 by the factor.

Examples:
> (disk 30 #:color "royalblue")

image

> (disk 30 #:color (scale-color 0.5 "royalblue"))

image

> (disk 30 #:color (scale-color 1.5 "royalblue"))

image

procedure

(color-series dc    
  max-step    
  step-delta    
  start    
  end    
  proc    
  set-pen?    
  set-brush?) → void?
  dc : (is-a?/c dc<%>)
  max-step : exact-nonnegative-integer?
  step-delta : (and/c exact? positive?)
  start : (or/c string? (is-a?/c color%))
  end : (or/c string? (is-a?/c color%))
  proc : (exact? . -> . any)
  set-pen? : any/c
  set-brush? : any/c
Calls a proc multiple times, gradually changing the pen and/or brush color for each call. For the first call, the current pen and/or brush color matches start; for the last call, it matches end; and for intermediate calls, the color is an intermediate color.

The max-step and step-delta arguments should be exact numbers; the procedure is called with each number from 0 to max-step inclusive using a step-delta increment.

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