► |  | Slideshow: Figure and Presentation Tools

1 | Creating Slide Presentations
2 | Making Pictures
3 | Making Slides
4 | Typesetting Racket Code
5 | Animations
| Bibliography
| Index

▼ | 2 | Making Pictures

2.1 | Pict Datatype
2.2 | Basic Pict Constructors
2.3 | Pict Combiners
2.4 | Pict Drawing Adjusters
2.5 | Bounding Box Adjusters
2.6 | Pict Finders
2.7 | More Pict Constructors
2.8 | Miscellaneous
2.9 | Rendering
2.10 | Conversion to Picts

On this page:

scale
rotate
ghost
linewidth
linestyle
colorize
cellophane
clip
inset/ clip
scale/ improve-new-text
black-and-white

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#### 2.4`` Pict Drawing Adjusters

> > procedure

> > (scale pict factor) → pict?

> pict : pict?
> factor : real?
> (scale pict w-factor h-factor) → pict?
> pict : pict?
> w-factor : real?
> h-factor : real?

Scales a pict drawing, as well as its bounding box. The drawing is scaled by adjusting the destination dc<%>’s scale while drawing the original pict.

> > procedure

> > (rotate pict theta) → pict?

> pict : pict?
> theta : real?

Rotates a pict’s drawing by theta radians counter-clockwise.

The bounding box of the resulting pict is the box encloses the rotated corners of pict (which inflates the area of the bounding box, unless theta is a multiple of half of pi). The ascent and descent lines of the result’s bounding box are the horizontal lines that bisect the rotated original lines; if the ascent line drops below the descent line, the two lines are flipped.

> > procedure

> > (ghost pict) → pict?

> pict : pict?

Creats a container picture that doesn’t draw the child picture, but uses the child’s size.

> > procedure

> > (linewidth w pict) → pict?

> w : (or/c real? #f)
> pict : pict?

Selects a specific pen width for drawing, which applies to pen drawing for pict that does not already use a specific pen width. A #f value for w makes the pen transparent (in contrast to a zero value, which means “as thin as possible for the target device”).

> > procedure

> > (linestyle style pict) → pict?

> style

> :

> (one-of/c 'transparent 'solid 'xor 'hilite
> 'dot 'long-dash 'short-dash 'dot-dash
> 'xor-dot 'xor-long-dash 'xor-short-dash
> 'xor-dot-dash)

> pict : pict?

Selects a specific pen style for drawing, which applies to pen drawing for pict that does not already use a specific pen style.

> > procedure

> > (colorize pict color) → pict?

> pict : pict?

> color

> :

> (or/c string?
> (is-a?/c color%)
> (list (integer-in 0 255)
> (integer-in 0 255)
> (integer-in 0 255)))

Selects a specific color drawing, which applies to drawing in pict that does not already use a specific color. The black-and-white parameter causes all non-white colors to be converted to black.

> > procedure

> > (cellophane pict opacity) → pict?

> pict : pict?
> opacity : (real-in 0 1)

Makes the given pict semi-transparent, where an opacity of 0 is fully transparent, and an opacity of 1 is fully opaque. See set-alpha for information about the contexts and cases when semi-transparent drawing works.

> > procedure

> > (clip pict) → pict

> pict : pict?

Clips a pict’s drawing to its bounding box.

> > procedure

> > (inset/clip pict amt) → pict?

> pict : pict?
> amt : real?
> (inset/clip pict h-amt v-amt) → pict?
> pict : pict?
> h-amt : real?
> v-amt : real?
> (inset/clip pict l-amt t-amt r-amt b-amt) → pict?
> pict : pict?
> l-amt : real?
> t-amt : real?
> r-amt : real?
> b-amt : real?

Insets and clips the pict’s drawing to its bounding box. Usually, the inset amounts are negative.

> > syntax

> > (scale/improve-new-text pict-expr scale-expr)

> (scale/improve-new-text pict-expr x-scale-expr y-scale-expr)

Like the scale procedure, but also sets current-expected-text-scale while evaluating pict-expr.

> > parameter

> > (black-and-white) → boolean?

> (black-and-white on?) → void?
> on? : any/c

A parameter that determines whether colorize uses color or black-and-white colors.
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