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# class Draw

### Table Of Contents

### class methods

- new

### attribute writers

- affine=
- align=
- decorate=
- density=
- encoding=
- fill=
- font=
- font_family=
- font_stretch=
- font_style=
- font_weight=
- gravity=
- pointsize=
- rotation=
- stroke=
- text_antialias=
- undercolor=

### drawing primitive methods

- affine
- arc
- bezier
- circle
- clip_path
- clip_rule
- clip_units
- color
- composite
- decorate
- define_clip_path
- ellipse
- encoding
- fill
- fill_opacity
- fill_rule
- font
- font_family

- font_stretch
- font_style
- font_weight
- gravity
- line
- matte
- opacity
- path
- pattern
- point
- pointsize
- polygon
- polyline
- pop
- push
- rectangle
- rotate
- roundrectangle

- scale
- skewx
- skewy
- stroke
- stroke_antialias
- stroke_dasharray
- stroke_dashoffset
- stroke_linecap
- stroke_linejoin
- stroke_miterlimit
- stroke_opacity
- stroke_width
- text
- text_align
- text_anchor
- text_antialias
- text_undercolor
- translate

### other instance methods

- annotate
- draw
- get_type_metrics
- inspect

## class methods

new | Magick::Draw.new [ { additional parameters } ] -> draw

Description

Creates a new Draw object. You can assign some initial values by setting attributes in the associated block. However, you will usually find it more useful to use one of the Draw instance methods to set these values while the primitives are being executed. When the values are initialized by new, they will be overridden by the corresponding instance method.

The attributes you can set are shown in the following table.

Method | Description
--- | ---
antialias=`true` or `false` | Initializes both stroke_antialias and text_antialias
font=font_name | See font
density="XxY" | Font density
pointsize=size | See pointsize and pointsize=
border_color="color_name" |
server_name="name" |
debug=`true` or `false` | See draw

Example

    primitives = Magick::Draw.new {
       self.font = "Courier"      # override default font
       }

ImageMagick API | CloneDrawInfo

## attribute writers

These methods are usually used to set attribute values for the annotate method. They may be set prior to calling annotate or in a block associated with the call. To set a value to be used when drawing with the draw method, use one of the drawing methods listed in the drawing primitive methods section, below.
affine= | draw.affine = anAffineMatrix
| The transformation matrix. See AffineMatrix. The default is the null transformation. Also see affine.
align= | draw.align = anAlignType
| The text alignment, left, center, or right. The default is LeftAlign. See also text_align.
decorate= | draw.decorate = aDecorationType
| The text decoration. See DecorationType. The default is NoDecorationType.
density= | draw.density = aString
| The text density in the x and y directions. The default is "72x72".
encoding= | draw.encoding = aString
| The text encoding. One of the following strings: "AdobeCustom", "AdobeExpert", "AdobeStandard", "AppleRoman", "BIG5", "GB2312", "Latin 2", "None", "SJISCode", "Symbol", "Unicode", "Wansung".
fill= | draw.fill = aString draw.fill = aPixel
| The name of the fill color. May also be a Pixel object. The default is "black".
font= | draw.font = aString
| The font name. The default is "Helvetica". See also font.
font_family= | draw.font_family = aString
| The font family name. For example, "arial" or "helvetica".
font_stretch= | draw.font_stretch = aStretchType
| A StretchType constant.
font_style= | draw.font_style = aStyleType
| A StyleType constant.
font_weight= | draw.font_weight = aWeightType
| A WeightType constant or one of the numbers 100, 200, 300, 400, 500, 600, 700, 800, or 900.
gravity= | draw.gravity = aGravityType
| The text gravity. The default is NorthWestGravity.
pointsize= | draw.pointsize = anInteger
| The font size. The default is 12.
rotation= | draw.rotation = aNumber
| Rotate the text. Specify the amount of rotation in degrees.
| See rotated_text.rb.
stroke= | draw.stroke = aString draw.stroke = aPixel
| The stroke color. This is the color used to outline the text. May also be a Pixel object. The default is "black".
text_antialias= | draw.text_antialias = `true` or `false`
| Whether the text is antialiased or not. The default is `true`.
undercolor= | draw.undercolor = aString draw.undercolor = aPixel
| If set, causes the text to be drawn over a box of the specified color. May be a color name or a Pixel object. See also text_undercolor.

Example

This example displays the effect of the following attribute values:

          font = "Helvetica"
          decorate = Magick::OverlineDecoration
          fill = "red"
          gravity = Magick::CenterGravity
          pointsize = 48
          stroke = "black"
          undercolor = "cyan"

Notice that, along with the text, the surrounding cyan box is outlined with black, the stroke color. For more examples, see annotate.

## drawing primitive methods

affine | draw.affine(sx, rx, ry, sy, tx, ty) -> draw
Description | Transforms the coordinate system by a 3x3 transformation matrix. See Coordinate system transformations in the Scalable Vector Graphics (SVG) 1.0 Specification.

Arguments

sx, sy
  The amount of scaling in the x and y directions
rx, ry
  The rotation in the x and y directions, in radians.
tx, ty
  The translation distances in the x and y directions

Example

`draw.affine(1, 0, 0, -1, 0, max_y)`

See also | rotate, scale, skewx, skewy, translate
arc | draw.arc(start_x, start_y, end_x, end_y, start_degrees, end_degrees) -> draw
Description | Draws an arc within a rectangle.

Arguments

start_x, start_y
  start point
end_x, end_y
  end point
start_degrees, end_degrees
  degree of rotation at start and end

Returns | self

Example

`draw.arc(130,30, 200,100, 45,90)`

bezier | draw.bezier(x1,y1, cx1,cy1, cx2,cy2, x2, y2...) -> draw
Description | Draw a cubic Bezier curve
Arguments | The arguments are pairs of points. At least 4 pairs must be specified. Each point xn, yn on the curve is associated with a control point cxn, cyn. The first point, x1, y1, is the starting point. The last point, xn, yn, is the ending point. Other point/control point pairs specify intermediate points on a polybezier curve.

Example

The following examples are taken from the Paths section of the Scalable Vector Graphics (SVG) 1.0 Specification.
`draw.bezier(100,200, 100,100, 400, 100, 400,200)`
`draw.bezier(100,200, 175,100, 475,100, 400,200)`
`draw.bezier(100,200, 25,100, 475, 100, 400,200)`
`draw.bezier(100,200, 100,50, 400, 350, 400,200)`
`draw.bezier(100,200, 175,100, 325, 100, 400,200)`
`draw.bezier(100,200, 100,100, 250,100, 250,200, 250,300, 400,300, 400,200)`

circle | draw.circle(origin_x, origin_y, perim_x, perim_y) -> draw
Description | Draw a circle centered on the point origin_x, origin_y and the point perim_x, perim_y on the perimeter.

Example

`draw.circle(125,125, 25,125)`

clip_path | draw.clip_path(pathname) -> draw
Description | Draws the clip path on the image mask. The clip path defines a clipping area, where only the contained area will be drawn upon. Areas outside of the clipping area are masked. Before using a clip-path, you must create it using the define_clip_path method.
Arguments | The name of the clip path.

Example

`draw.clip_path('example')`

See also | define_clip_path
clip_rule | draw.clip_rule(`"evenodd"` or `"nonzero"`) -> draw
Description | Specify how to determine if a point on the image is inside clipping region. See the 'fill-rule' property in the Scalable Vector Graphics (SVG) 1.0 Specification for a complete description and examples.
Arguments | Either "evenodd" or "nonzero".
clip_units | draw.clip_units(`"userSpace"` or `"userSpaceOnUse"` or `"objectSpace"`) -> draw
Description | Defines the coordinate space within the clipping region. See the `clipPathUnits` property in the Scalable Vector Graphics (SVG) 1.0 Specification for a complete description and examples.
Arguments | Either "userSpace", "userSpaceOnUse", or "objectSpace".
color | draw.color(x, y, aPaintMethod) -> draw
Description | Set color in image according to the specified PaintMethod constant.
Arguments | See the PaintMethod constants.
Example | `draw.color(x, y, Magick::ReplaceMethod)`
composite | draw.composite(x, y, width, height, composite_image, op=`Magick::OverCompositeOp`) -> draw
Description | Composite `composite_image` with the background image.

Arguments

x, y
  The offset of `composite_image` relative to the background image.
width, height
  Scale the `composite_image` to this size. If either value is 0, `composite_image` is not scaled.
composite_image
  Either an imagelist or a image. If an imagelist, uses the current image.
op
  A CompositeOperator constant.

Examples

See also | Image#composite
decorate | draw.decorate(aDecorationType) -> draw
Description | Specify text decoration.
Arguments | See the DecorationType constants.
Example | `draw.decorate(Magick::LineThroughDecoration)`
See also | decorate=
define_clip_path | draw.define_clip_path(aString) { block } -> draw

Description

Define a clip-path. Within block, call other drawing primitive methods (rectangle, polygon, text, etc.) to define the clip-path. The union of all the primitives (excluding the effects of rendering methods such as stroke_width, etc.) is the clip-path. After the clip-path is invoked by the clip-path method, anything drawn on the image inside the clip-path will appear. Anything drawn outside the clip-path will be hidden. (See clip_rule for a definition of how ImageMagick decides what is "inside" and what is "outside" of the clip-path.)

Arguments | The name of the clip-path.
Example | See the example for clip_path.
See also | clip_path
ellipse | draw.ellipse(origin_x, origin_y, width, height, arc_start, arc_end) -> draw
Description | Draw an ellipse.

Arguments

origin_x, origin_y
  The center of the ellipse
width, height
  The horizontal and vertical radii
arc_start
  Where to start the ellipse, in degrees. 0 degrees is at 3 o'clock.
arc_end
  Where to end the ellipse, in degrees

Example

`draw.ellipse(180,125, 150,75, 0, 270)`

encoding | draw.encoding(`"UTF-8"`) -> draw
Description | Specify the font encoding as "UTF-8".
Arguments | "UTF-8". (Note: This looks like a placeholder in ImageMagick. All other arguments are ignored.)
See also | encoding=
fill | draw.fill(aString) -> draw
Description | Specify the color or pattern with which graphical elements are filled.
Arguments | A color name or pattern name.
Example | `draw.fill('red')`
Aliases | fill_color, fill_pattern
fill_opacity | draw.fill_opacity(aFloat) -> draw draw.fill_opacity(aString -> draw)
Description | Specify the fill opacity.
Arguments | A number between 0 and 1, inclusive, or a percentage represented as a string, i.e. '30%'. The argument .3 is the same as '30%'.

Example

    draw.fill_opacity(.4)
    draw.fill_opacity('40%')

See the example for opacity.

See also | opacity stroke_opacity
fill_rule | draw.fill_rule(`"evenodd"` or `"nonzero"`) -> draw
Description | Specify how to determine if a point on the image is inside a shape. See the 'fill-rule' property in the Scalable Vector Graphics (SVG) 1.0 Specification for a complete description and examples.
Arguments | Either "evenodd" or "nonzero".
font | draw.font(aString) -> draw
Description | Specify the font to draw text with.

Arguments

The font name or filename. You can tag a font to specify whether it is a Postscript, Truetype, or OPTION1 font. For example, Arial.ttf is a Truetype font, ps:helvetica is Postscript, and x:fixed is OPTION1.

The font name can be a complete filename such as `"/mnt/windows/windows/fonts/Arial.ttf"`. The font name can also be a fully qualified X font name such as `"-urw-times-medium-i-normal--0-0-0-0-p-0-iso8859-13"`.

Example | `draw.font('Helvetica')`
font_family | draw.font_family(aString) -> draw
Description | Specify the font family.
Arguments | A font family name such as "arial" or "helvetica".
Example | See the example for text.
font_stretch | draw.font_stretch(aStretchType) -> draw
Description | Specify the spacing between text characters.
Arguments | A StretchType constant.
Example | `draw.font_stretch(Magick::UltraCondensedStretch)`
font_style | draw.font_style(aStyleType) -> draw
Description | Specify the font style, i.e. italic, oblique, or normal.
Arguments | A StyleType constant.
Example | See the example for text.
font_weight | draw.font_weight(aWeightType) -> draw
Description | Specify the font weight. For example, "bold" or "normal".
Arguments | A WeightType constant, or one of the numbers 100, 200, 300, 400, 500, 600, 700, 800, or 900.
Example | See the example for text.
gravity | draw.gravity(aGravityType) -> draw
Description | Specify how the text is positioned. The default is `Magick::NorthWestGravity`.
Arguments | A GravityType constant.
Example |
See also | text
line | draw.line(here_x, here_y, there_x, there_y) -> draw
Description | Draw a line from here to there.

Arguments

here_x, here_y
  The starting point.
there_x, there_y
  The ending point.

Example

`draw.line(50,50, 50,200) draw.line(50,200, 200,200) draw.line(200,200, 50,50)`

matte | draw.matte(x,y, aPaintMethod) -> draw
Description | Make the image transparent according to the specified PaintMethod constant.

Arguments

x, y
  Point in image to use, along with the PaintMethod constant, to set transparent pixels in the image.
aPaintMethod
  One of the following PaintMethod constants:
  PointMethod
    Make the pixel at (x,y) transparent.
  ReplaceMethod
    Make all pixels that are the same color as the pixel at (x,y) transparent.
  FloodfillMethod
    Make all the pixels surrounding the pixel at (x,y) transparent, until encountering pixels that fail to match color at (x,y).
  FillToBorderMethod
    Make all the pixels surrounding the pixel at (x,y) transparent, until encountering pixels that match the border color.
  ResetMethod
    Make the entire image transparent.

See also | Image#matte_point, Image#matte_replace, Image#matte_floodfill, Image#matte_fill_to_border, Image#opaque, Image#transparent
opacity | draw.opacity(opacity) -> draw
Description | Specify the fill and stroke opacities.
Argument | Either a number between 0 and 1, or a percentage represented as a string, i.e. "25%". The string argument "25%" is the same as the numeric argument 0.25. Both the fill and stroke opacities are set to the specified value.
Example |
See also | fill_opacity stroke_opacity
path | draw.path(aString)
Description | Draw using SVG-compatible path drawing commands. See "Paths" in the Scalable Vector Graphics (SVG) 1.0 Specification.
Arguments | A string containing SVG moveto, line, curve, arc, or closepath instructions. The string is equivalent to the d attribute in an SVG 'path' element.

Example

These examples are all taken from the SVG path examples.

Example arcs01
Example quad01
Example cubic01

pattern | draw.pattern(name, x, y, width, height) { pattern primitives } -> draw
Description | Define a pattern that can be used as the fill or stroke pattern.

Arguments

name
  The name of the pattern. The pattern is used in a fill or stroke method by specifying its name.
x, y, width, height
  Define how the pattern is tiled. The pattern rectangles start at (x + m*width, y+n*height) for the values of n and m as necessary to fill the space.
pattern primitives
  The method calls that draw the pattern.

Example

See also | fill, stroke
point | draw.point(x, y) -> draw
Description | Set the pixel at x,y to the fill color.

Arguments

x, y
  The pixel location

Example | `draw.point(30, 40)`
pointsize | draw.pointsize(anInteger) -> draw
Description | Set the font size in points. The default is 12.
Example | See the example for text.
Alias | font_size
polygon | draw.polygon(x1, y1,...,xN, yN) -> draw
Description | Draw a polygon.
Arguments | The arguments are a sequence of 2 or more points. If the last point is not the same as the first, the polygon is closed by drawing a line from the last point to the first.

Example

This example is taken from the The 'polygon' element in the Scalable Vector Graphics (SVG) 1.0 Specification

polyline | draw.polyline(x1, y1,...,xN, yN) -> draw
Description | Draw a polyline. Unlike a polygon, a polyline is not automatically closed.
Arguments | A sequence of 2 or more points.

Example

This example is taken from the The 'polyline' element in the Scalable Vector Graphics (SVG) 1.0 Specification

pop | draw.pop -> draw
Description | Restore the graphics context to its previous state.
Example | `draw.pop`
See also | push
push | draw.push -> draw
Description | Save the current state of the graphics context, including the attribute settings and the current set of primitives. Use the pop primitive to restore the state. Note: The push and pop primitives are probably not as useful in RMagick as they are in C language ImageMagick programs, since it is easy to create separate draw objects, each with its own set of properties and primitives.
Example | `draw.push`
See also | pop
rectangle | draw.rectangle(x1, y1, x2, y2) -> draw
Description | Draw a rectangle.

Arguments

x1, y1
  The upper left hand corner of the rectangle
x2, y2
  The lower right hand corner of the rectangle

Example

`draw.rectangle(20,20, 280,180)`

rotate | draw.rotate(degrees) -> draw
Description | Specify a rotation transformation to the coordinate space. The default is 0.
Arguments | The amount of rotation, in degrees. The angle of rotation is clockwise, so 90° is south.

Example

`draw.rotate(45)`

See also | affine
roundrectangle | draw.roundrectangle(x1, y1, x2, y2, cw, ch) -> draw
Description | Draw a rectangle with rounded corners.

Arguments

x1, y1
  The upper left hand corner of the rectangle
x2, y2
  The lower right hand corner of the rectangle
cw, ch
  The corner width and height

Example

`draw.roundrectangle(20,20, 280,180, 8, 8)`

scale | draw.scale(sx, sy) -> draw
Description | Define a scale transformation to the coordinate space. The default scale is (1.0, 1,0).

Arguments

sx, sy
  The amount of scaling in the x and y dimensions.

Example

`draw.scale(1.5, 1.25)`

See also | affine skewx skewy
skewx | draw.skewx(aFloat) -> draw
Description | Define a skew tranformation along the x-axis.
Arguments | The amount of skew, in degrees.

Example

`draw.skewx(30)`

See also | skewy, rotate
skewy | draw.skewy(aFloat) -> draw
Description | Define a skew tranformation along the y-axis.
Arguments | The amount of skew, in degrees.

Example

`draw.skewy(30)`

See also | skewx, rotate
stroke | draw.stroke(aString) -> draw
Description | Specify the stroke color or pattern.
Arguments | A color name or pattern name.
Example | `draw.stroke('red')`
Aliases | stroke_color, stroke_pattern
stroke_antialias | draw.stroke_antialias(`true` or `false`) -> draw
Description | Specify if stroke should be antialiased. The default is `true`.
Example | `draw.stroke_antialias(false)`
stroke_dasharray | draw.stroke_dasharray(x1,...,xn) -> draw
Description | Describe a pattern of dashes to be used when stroking paths. The arguments are a list of pixel widths of alternating dashes and gaps.
Arguments | The first argument is the width of the first dash. The second is the width of the gap following the first dash. The third argument is another dash width, followed by another gap width, etc. If you specify an odd number of arguments, the arguments are repeated to produce an even number. All arguments must be > 0. To produce a solid stroke, specify no arguments, i.e. `stroke_dasharray()`
Example |
See also | stroke_dashoffset
stroke_dashoffset | draw.stroke_dashoffset(anInteger) -> draw
Description | Specify the initial distance into the dash pattern.
Arguments | The initial distance into the dash pattern. The units are pixels.
Example | See stroke_dasharray.
See also | stroke_dasharray
stroke_linecap | draw.stroke_linecap(aString) -> draw
Description | Specify how the line ends should be drawn.
Arguments | One of "butt", "round", or "square".

Example

The following example is from the Stroke Properties section of the Scalable Vector Graphics (SVG) 1.0 Specification.

stroke_linejoin | draw.stroke_linejoin(aString) -> draw
Description | Specify how corners are drawn.
Arguments | One of "miter", "round", or "bevel".

Example

The following example is from the Stroke Properties section of the Scalable Vector Graphics (SVG) 1.0 Specification.

stroke_miterlimit | draw.stroke_miterlimit(aFloat) -> draw
Description | Specify a constraint on the length of the "miter" formed by two lines meeting at an angle. If the angle if very sharp, the miter could be very long relative to the line thickness. The miter limit is a limit on the ratio of the miter length to the line width.
Arguments | A number >= 1. The limit on the ratio of the miter length to the line width.
Example | `draw.stroke_miterlimit(2.0)`
stroke_opacity | draw.stroke_opacity(aFloat) -> draw draw.stroke_opacity(aString) -> draw
Description | Specify the stroke opacity.
Arguments | A number between 0 and 1, inclusive, or a percentage represented as a string, i.e. '30%'. The argument .3 is the same as '30%'.

Example

    draw.stroke_opacity(.4)
    draw.stroke_opacity('40%')

See the example for opacity.

See also | opacity fill_opacity
stroke_width | draw.stroke_width(anInteger) -> draw
Description | Specify the stroke width in pixels.
Example |
text | draw.text(x,y, text) -> draw
Description | Draw text at the location specified by (x,y). Use gravity to position the text relative to (x, y). Specify the text appearance with the font, font_family, font_stretch, font_style, and font_weight methods. Use the text_antialias method to set antialiasing on or off.

Arguments

x, y
  The text position.
text
  The text.

Example |
See also | annotate
text_align | draw.text_align(anAlignType) -> draw
Description | Align text relative to the starting point.
Arguments | An AlignType constant.
Example |
text_anchor | draw.text_anchor(anAnchorType) -> draw
Description | Align text relative to the starting point. This is the SVG 1.1 equivalent to text_align.
Arguments | One of the constants `Magick::AnchorStart`, `Magick::AnchorMiddle`, or `Magick::AnchorEnd`.
text_antialias | draw.antialias(`true` or `false`) -> draw
Description | Specify if the text is to be antialiased.
Arguments | Either `true` or `false`. The default is `true`.

Example

The character on the left is not antialiased. The character on the right is antialiased.

text_undercolor | draw.undercolor(aString) -> draw
Description | The color to draw underneath text. The default is transparent.
Arguments | A color name.
Example |
translate | draw.translate(tx, ty) -> draw
Description | Specify a translation operation on the coordinate space.

Arguments

tx, ty
  The amount of translation in the x and y directions.

Example |
See also | affine

## other instance methods

annotate | draw.annotate(img, width, height, x, y, text) [ { additional parameters } ] -> draw

Description

Annotates a image with text. The text is positioned according to the gravity attribute around the rectangle described by the x, y, width, and height arguments. If either of the width or height arguments are omitted, uses the image width - x and the image height - y to compute the rectangle width and height. The attributes described in attribute writers, above, influence the appearance and position of the text. These attributes may be set within the optional additional parameters block.

Arguments

img
  the image or imagelist to be annotated
width
  width of the rectangle within which the text is positioned
height
  height of the rectangle within which the text is positioned
x
  x offset of the rectangle
y
  y offset of the rectangle
text
  the text

Returns | self
Example | See attribute writers, also gravity.rb
ImageMagick API | AnnotateImage

Advanced

You can include information about the image by including one or more of the special characters shown in this table.

%b | the file size in bytes
%c | comment
%d | the directory in which the image file resides
%e | the image filename extension
%f | original image filename
%h | image height
%i | current image filename
%k | number of unique colors
%l | the label string
%m | the image file format
%n | number of images in the image sequence (for RMagick, this is always 1)
%o | output image filename
%p | image page number
%q | image depth
%s | scene number (within a sequence, not to be confused with the Image#scene attribute)
%t | image filename without extension
%u | unique temporary filename
%w | image widith
%x | x resolution
%y | y resolution

draw | draw.draw(img) -> draw
Description | Draws the list of graphic primitives on the specified image.
Arguments | Either an imagelist or a image. If an imagelist, draws on the current image.
Example | See the other examples for the Draw class.
ImageMagick API | DrawImage

Notes

Calling draw does not affect the list of primitives. Each time you call draw the primitives will be re-executed from the beginning. However, if you establish the initial value of some draw object attributes using the optional parameters to new, or by setting one or more attributes, keep in mind that the initial state will not be restored after draw completes. If you want to use the draw object again, you must reset the attributes yourself.

get_type_metrics | draw.get_type_metrics(anImage, aString) -> aTypeMetric
Description | Returns information for a specific string if rendered on a image.

Arguments

image
  The image on which the string will be rendered. ImageMagick uses the attributes of the image (font name, pointsize, etc.) to compute the metrics.
string
  The string to be rendered.

Returns

A Magick::TypeMetric struct. This structure has the following attributes. (The descriptions are taken from the Magick++ documentation and source code.)

Accessor | Description
--- | ---
pixels_per_em.x | Character width. (See Point.)
pixels_per_em.y | Character height
ascent | Distance in pixels from the text baseline to the highest/upper grid coordinate used to place an outline point. Always a positive value.
descent | Distance in pixels from the baseline to the lowest grid coordinate used to place an outline point. Always a negative value.
width | Text width in pixels
height | Text height in pixels
max_advance | Maximum horizontal advance (advance from the beginning of a character to the beginning of the next character) in pixels.
bounds.x1 |
bounds.x2 |
bounds.y1 |
bounds.y1 |
underline_position |
underline_thickness |

ImageMagick API | GetTypeMetrics

Advanced

The Magick++ documentation for its TypeMetric class provides this useful additional information. (I've changed it a bit to use RMagick names.)

The TypeMetric class provides the means to pass data from the Draw class's get_type_metric method to the user. It provides information regarding font metrics such as ascent, descent, text width, text height, and maximum horizontal advance. The units of these font metrics are in pixels...(T)he metrics are dependent on the current Image font (default Ghostscript's "Helvetica"), pointsize (default 12 points), and x/y resolution (default 72 DPI) settings.

The pixel units may be converted to points (the standard resolution-independent measure used by the typesetting industry) via the following equation:

> size_points = (size_pixels * 72)/resolution

where resolution is in dots-per-inch (DPI). This means that at the default image resolution, there is one pixel per point.

Note that a font's pointsize is only a first-order approximation of the font height (ascender + descender) in points. The relationship between the specified pointsize and the rendered font height is determined by the font designer.

See FreeType Glyph Conventions for a detailed description of font metrics related issues.

inspect | draw.inspect -> draw
Description | Displays the list of primitives that have been added to the draw object.

Example

    draw.inspect »
       "stroke red
        fill transparent
        rectangle 20,20 380,180
        line 200,20 200,180
        line 20,100 380,100
        stroke transparent
        fill black"

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