# class Tioga::TeX_Text

Text in tioga goes to TeX for typesetting: you aren't using a partial emulation that is sort-of-like TeX, you are using the real thing.

Since text strings in tioga are passed directly to TeX, you can basically do anything in the text of figures that you can do with text in TeX. The text string can include embedded commands to change font size, family, or whatever. However, more commonly the text string will leave the font selection to a higher level in the document. In tioga it is easy for you to use the “NFSS”, TeX's “New Font Selection Scheme” that specifies the font by independently setting family, series, shape, and size. Families include roman, sans serif, and typewriter.

Series include medium and bold face. Shapes include upright, italic, slant, and small caps. All these, and the size, are set in the SetTiogaFontInfo command in the TeX file preamble. The tioga defaults for size, family, series, and shape are 10 point roman, medium, and upright. You can change these by means of the attributes `tex_fontfamily`, `tex_fontseries`, `tex_fontshape`, and tex_fontsize. Just like for the tex_preview page and figure sizes, these are given as strings to be copied to the TeX preview file as part of the SetTiogaFontInfo definition.

Text is sized by giving a scale factor relative to a base size. The base size is given by the attribute `default_font_size`, that is initialized to 10 and can be changed using set_default_font_size. The scale factor is called `default_text_scale`, is initialized to 1.0, and is changed by rescale_text. When you do a `show_text` command in tioga, the call can include an additional scale factor. The product of this extra factor times the `default_text_scale` times the `default_font_size` determines the size in big points on the output page. At least that's the size the text will have if the output page doesn't get scaled up or down, and the TeX document doesn't decide to change things! With text that is being passed to TeX for typesetting, the final decisions aren't made until the last moment. See `Page_Frame_Bounds` for more details.

See `Tutorial::TextForTeX` for information about how to add packages and how (and how not) to enter text for TeX.

### Public Instance Methods

alignment click to toggle source
alignment = an_alignment

Default for text vertical alignment. Valid settings are predefined constants: `ALIGNED_AT_TOP`, `ALIGNED_AT_MIDHEIGHT`, `ALIGNED_AT_BASELINE`, and `ALIGNED_AT_BOTTOM`. See also `justification`.

    # File lib/Tioga/TeX_Text.rb, line 325
    def alignment
    end

check_label_clip(x, y) click to toggle source

Returns `true` if the point given by the figure coordinates (x, y) is inside the current label clipping margins. The routine `show_label` uses this to filter out unwanted text by testing the reference point. If the point passes this test, then `show_label` calls `show_text`; otherwise, it simply returns without showing the text.

    # File lib/Tioga/TeX_Text.rb, line 303
    def check_label_clip(x, y)
    end

default_font_size click to toggle source

Default font size in points (relative to the `default_font_size`). Is initialized to 10.0 and changed by set_default_font_size. The intention is that this gets set rarely and most font sizing is done using rescale_text.

    # File lib/Tioga/TeX_Text.rb, line 450
    def default_font_size
    end

default_text_height_dx click to toggle source

Height of text having the `default_text_scale` as measured in x figure coordinates.

    # File lib/Tioga/TeX_Text.rb, line 332
    def default_text_height_dx
    end

default_text_height_dy click to toggle source

Height of text having the `default_text_scale` as measured in y figure coordinates.

    # File lib/Tioga/TeX_Text.rb, line 339
    def default_text_height_dy
    end

default_text_scale click to toggle source

Default factor determining text size (relative to the default font size). Is initialized to 1.0 and changed by rescale_text.

    # File lib/Tioga/TeX_Text.rb, line 439
    def default_text_scale
    end

get_text_size(name) click to toggle source

Returns information about the text measure named name. It returns a hash with the following information:

    * _[xy][tb][lr]_ the X/Y coordinates of the Top/Bottom Left/Right point of the
      box around the text (top, left, right and bottom are relative to the text
      natural orientation)
    * _just_ the text justification
    * _angle_ the text's angle, in degrees
    * _tex_measured_depth_, _tex_measured_height_, tex_measured_width_, the
      text's depth, width and height as measured by TeX,
     (does not take scaling into accound)
    * _xanchor_, _yanchor_: the page coordinates of the position of the text
      (the ones that were given to #show_text)
    * _points_ an array of (x,y) coordinates of the points that make the box,
      in the order bottom left, bottom right, top right, top left.
    * _depth_, _width_, _height_ : the size of the text.
    * _align_ the alignment of the text

All the measures are given in postscript points, which means you need to multiply by 10 before using the with `Page_Frame_Bounds#convert_output_to_figure_x` `Page_Frame_Bounds#convert_output_to_figure_y`. See the example

Please make sure you test the presence of one key before using it, as any code using measures has to run twice: one first time to typeset the text and ask LaTeX for information about its size, and the second time to actually use the information. You don't need to call the code twice as it is done automatically, but keep in mind that in the first run, the returned hash will be empty.

    def text_size_with_rotation
      t.stroke_rect(0,0,1,1)
      t.rescale(0.5)

      equation = '\int_{-\infty}^{\infty} \! e^{-x^{2}}\, \! dx = \sqrt{\pi}'
      text = "\\fbox{$\\displaystyle #{equation}$}"

      nb = 5
      nb.times do |i|
        scale = 0.5 + i * 0.2
        angle = i * 37
        x = (i+1)/(nb+1.0)
        y = x
        color = [1.0 - i * 0.2, i*0.2, 0]
        t.show_text('text' => text, 'color' => color, 'x' => x,
                    'y' => x,
                    'alignment' => ALIGNED_AT_MIDHEIGHT,
                    'scale' => scale , 'measure' => "box#{i}",
                    'angle' => angle )
        size = t.get_text_size("box#{i}")
        if size.key? 'points'
          xs = Dvector.new
          ys = Dvector.new
          for x,y in size['points']
            xs << t.convert_output_to_figure_x(x)
            ys << t.convert_output_to_figure_y(y)
          end
          t.stroke_color = color
          t.line_type = Line_Type_Dashes
          t.stroke_rect(xs.min, ys.min,
                        (xs.max - xs.min),(ys.max - ys.min))
        end
      end
    end

    # File lib/Tioga/TeX_Text.rb, line 282
    def get_text_size(name)
    end

justification click to toggle source
justification = a_justification

Default for text horizontal justification. Valid settings are predefined constants: `LEFT_JUSTIFIED`, `CENTERED`, and `RIGHT_JUSTIFIED`. See also `alignment`.

    # File lib/Tioga/TeX_Text.rb, line 315
    def justification
    end

label_bottom_margin click to toggle source
label_bottom_margin = a_float

Size of margin on bottom of frame measured as a fraction of frame height, with positive values corresponding to margins on the inside of the frame, and negative values to margins on the outside. The `show_label` routine discards text having its reference point below this position.

    # File lib/Tioga/TeX_Text.rb, line 383
    def label_bottom_margin
    end

label_left_margin click to toggle source
label_left_margin = a_float

Size of margin on left of frame measured as a fraction of frame width, with positive values corresponding to margins on the inside of the frame, and negative values to margins on the outside. The `show_label` routine discards text having its reference point to the left of this position.

    # File lib/Tioga/TeX_Text.rb, line 350
    def label_left_margin
    end

label_right_margin click to toggle source
label_right_margin = a_float

Size of margin on right of frame measured as a fraction of frame width, with positive values corresponding to margins on the inside of the frame, and negative values to margins on the outside. The `show_label` routine discards text having its reference point to the right of this position.

    # File lib/Tioga/TeX_Text.rb, line 361
    def label_right_margin
    end

label_top_margin click to toggle source
label_top_margin = a_float

Size of margin on top of frame measured as a fraction of frame height, with positive values corresponding to margins on the inside of the frame, and negative values to margins on the outside. The `show_label` routine discards text having its reference point above this position.

    # File lib/Tioga/TeX_Text.rb, line 372
    def label_top_margin
    end

rescale_text(scale) click to toggle source

Changes the `default_text_scale` attribute by multiplying it times scale. This also updates the `default_text_height_dx` and `default_text_height_dy` attributes to match the new setting for default_text_scale. See also rescale.

    # File lib/Tioga/TeX_Text.rb, line 289
    def rescale_text(scale)
    end

set_default_font_size(size, update_size_string) # size in points click to toggle source

Sets the font size in points. If the 'update_size_string' flag is true, then the 'tex_fontsize' attribute will be set to match the new font size. The intention is that `set_default_font_size` gets called rarely and most font sizing is done using rescale_text.

    # File lib/Tioga/TeX_Text.rb, line 460
    def set_default_font_size(size, update_size_string = true)
    end

show_label(dict) click to toggle source

Calls `check_label_clip` with the location for the text reference point from the dict. If `check_label_clip` returns `false`, this routine simply returns. Otherwise, it passes the dict to show_text.

    # File lib/Tioga/TeX_Text.rb, line 295
    def show_label(dict)
    end

show_text(dict) click to toggle source

This routine takes care of text that is being sent to TeX for typesetting (see also show_marker for text being used as graphics and sent directly to PDF).

The location of the reference point for the text can be given either in figure coordinates ('x' and 'y', or 'at') or relative to an edge of the frame ('side', 'position', and 'shift').

You can optionally provide a color as an RGB triple which will be used in a 'textcolor' command for TeX enclosing the rest of the text.

The text is scaled by the product of the 'scale' entry times the current value of the `default_text_scale` attribute. It is rotated by the given 'angle'.

The reference point can be specified horizontally ('justification') and vertically ('alignment').

The 'text' to be sent to TeX can contain anything that TeX will let you put in a box. In addition to the usual text and inline math, you can also do display math, lists, tables, etc.

You can even define your own commands in your TeX preamble and then use those commands as part of the text in the figure.

NOTE: When entering text for TeX in your Ruby program, you'll generally want to use single quotes around the string rather than double quotes. With single quotes, backslashes are treated as normal characters (except for the two special cases of ' and \), so TeX commands using backslashes don't cause trouble.

With double quotes, Ruby uses backslash for a variety of escape characters such as newline (n) and tab (t), so the backslashes for TeX need to be entered as \ pairs to be safe. Compare '$nusimtau$' to the equivalent form “$\\nu\\sim\\tau$” and the incorrect form “$nusimtau$”.

Starting from `Tioga` 1.7, `Tioga` can measure the TeX text it typesets. For that purpose, provide `show_text` with a 'measure' dictionnary entry that serves as a key to retrieve the information using `get_text_size`.

Dictionary Entries

    'text'            => a_string        # to be processed by TeX
    'side'            => a_side          # TOP, BOTTOM, LEFT, or RIGHT
    'loc'                                # alias for 'side'
    'position'        => a_float         # fractional distance along side from bottom left
    'pos'                                # alias for 'position'
    'shift'           => a_float         # distance away from side in units of text height
    'at'              => [ x, y ]        # figure coordinates for text reference point
    'point'                              # alias for 'at'
    'x'               => a_float         # x location for reference point
    'y'               => a_float         # y location for reference point
    'color'           => a_color         # default is to omit color specification
    'scale'           => a_float         # scale relative to default_text_scale.  default 1
    'angle'           => a_float         # degrees to rotate.  default 0
    'alignment'       => an_alignment    # see discussion of alignment
    'justification'   => a_justification # see discussion of justification
    'measure'         => a_string        # the name of the measure

Examples

    def math_typesetting
        centerx = t.bounds_xmin + 0.5 * t.bounds_width
        equation =
            '\int_{-\infty}^{\infty} e^{\color{Red}-x^{2}}\, ' +
            '\! dx = \color{Green}\sqrt{\pi}'
        t.justification = CENTERED
        t.rescale_text(0.8)
        t.show_text(
            'text'=>'Inline Math Mode',
            'x'=>centerx,
            'y' => t.bounds_ymin + 0.88 * t.bounds_height)
        t.show_text(
            'text'=>'Display Math Mode',
            'x'=> centerx,
            'y' => t.bounds_ymin + 0.46 * t.bounds_height)
        t.rescale_text(0.8)
        t.show_text(
            'text'=>'$' + equation + '$',
            'x'=> centerx,
            'y' => t.bounds_ymin + 0.78 * t.bounds_height,
            'scale'=>1.3)
        t.show_text(
            'text'=>'$' + equation + '$',
            'x'=> centerx,
            'y' => t.bounds_ymin + 0.64 * t.bounds_height,
            'angle' => 10, 'scale'=>1.3)
        equation = '\begin{displaymath}' + equation + '\end{displaymath}'
        equation = '\parbox{15em}{' + equation + '}'
        t.show_text(
            'text'=>equation,
            'x'=> centerx,
            'y' => t.bounds_ymin + 0.33 * t.bounds_height,
            'scale'=>1.3)
        t.show_text(
            'text'=>equation,
            'x' => centerx,
            'y' => t.bounds_ymin + 0.16 * t.bounds_height,
            'angle' => 10,
            'scale'=>1.3)
    end

    def strings
        t.stroke_rect(0,0,1,1)
        center_x = 0.5; center_y = 0.5; len = 0.125
        hls = t.rgb_to_hls(Red)
        angles = 10
        delta = 360.0/angles
        equation = '\int_{-\infty}^{\infty} \! e^{-x^{2}}\, \! dx = \sqrt{\pi}'
        text =
            '\parbox{15em}{\begin{displaymath}' +
            equation + '\end{displaymath}}'
        angles.times do |angle|
            angle *= delta
            dx = len*cos(angle*RADIANS_PER_DEGREE)
            dy = len*sin(angle*RADIANS_PER_DEGREE)
            x = center_x + 2*dx; y = center_y + 2*dy;
            text_color = t.hls_to_rgb([angle/1.8 + 200, hls[1], hls[2]])
            t.show_text('text' => text, 'color' => text_color, 'x' => x, 'y' => y,
                'alignment' => ALIGNED_AT_MIDHEIGHT,
                'scale' => 0.7, 'angle' => t.convert_to_degrees(dx,dy))
        end
    end

    def minipages
        centerx = t.bounds_xmin + 0.5 * t.bounds_width
        t.show_text(
            'text' => 'Examples using paragraph boxes',
            'x' => centerx,
            'y' => 0.9)
        t.rescale_text(0.5)
        t.justification = CENTERED
        str2 =
            'The \textcolor{Red}{minipage} is a vertical alignment ' +
            'environment with a \textcolor{Red}{specified width}.  ' +
            'It can contain paragraphs, lists, tables, ' +
            'and equations.  Hyphenation and formatting is automatic.'
        str2 = '\parbox{15em}{' + str2 + '}'
        t.show_text(
            'text' => str2,
            'x'=> centerx,
            'y' => t.bounds_ymin + 0.68 * t.bounds_height)
        t.show_text(
            'text' => str2,
            'x'=> centerx,
            'y' => t.bounds_ymin + 0.30 * t.bounds_height, 'angle' => 20)
    end

    def framebox
        centerx = t.bounds_xmin + 0.5 * t.bounds_width
        t.justification = CENTERED
        t.show_text(
            'text' => 'Examples using \textbackslash framebox',
            'x' => centerx, 'y' =>0.8)
        dx = 0.05; y = 0.6; dy = -0.15; t.line_width = 0.7; t.stroke_color = Blue
        t.rescale_text(0.75)
        t.show_text(
            'text' => '\framebox[20em][c]{\textbackslash framebox[20em][c]\{ a, b, c \}}',
            'at' => [centerx, y])
        y += dy
        t.show_text(
            'text' => '\framebox[20em][l]{\textbackslash framebox[20em][l]\{ a, b, c \}}',
            'at' => [centerx, y])
        y += dy
        t.show_text(
            'text' => '\framebox[20em][r]{\textbackslash framebox[20em][r]\{ a, b, c \}}',
            'at' => [centerx, y])
        y += dy
        t.show_text(
            'text' => '\framebox[20em][s]{\textbackslash framebox[20em][s]\{ a, b, c \}}',
            'at' => [centerx, y])
    end

    # File lib/Tioga/TeX_Text.rb, line 209
    def show_text(dict)
    end

tex_fontfamily click to toggle source
tex_fontfamily = a_string # giving the font family

This string will be used as the basic font family specification in the preview TeX file. Valid strings include 'rmdefault', 'sfdefault', and 'ttdefault', for roman face, sans serif face, and typewriter face, respectively.

See also: `tex_fontsize`, `tex_fontseries`, and tex_fontshape.

    # File lib/Tioga/TeX_Text.rb, line 483
    def tex_fontfamily
    end

tex_fontseries click to toggle source
tex_fontseries = a_string # giving the font series

This string will be used as the basic font series specification in the preview TeX file. Valid strings include 'mddefault' and 'bfdefault', for medium and bold face, respectively.

See also: `tex_fontsize`, `tex_fontfamily`, and tex_fontshape.

    # File lib/Tioga/TeX_Text.rb, line 494
    def tex_fontseries
    end

tex_fontshape click to toggle source
tex_fontshape = a_string # giving the font shape

This string will be used as the basic font shape specification in the preview TeX file. Valid strings include *'updefault', 'itdefault', 'sldefault', and 'scdefault', for upright, italic, slant, and small caps, respectively.

See also: `tex_fontsize`, `tex_fontfamily`, and tex_fontseries.

    # File lib/Tioga/TeX_Text.rb, line 506
    def tex_fontshape
    end

tex_fontsize click to toggle source
tex_fontsize = a_string # giving the font size in points

This string will be used as the basic font size specification in the preview TeX file. Valid strings include things like '10.0' or '12.0'.

See also: `tex_fontfamily`, `tex_fontseries`, and tex_fontshape.

    # File lib/Tioga/TeX_Text.rb, line 471
    def tex_fontsize
    end

tex_xaxis_numeric_label click to toggle source
tex_xaxis_numeric_label = a_string

The string for a numeric label is put in this TeX command string to be formatted. For example,

    $#1$

will give the numbers in math mode, while

    $\mathsf{#1}$

will show the label using the math sans-serif font. Alias for xaxis_numeric_label_tex.

    # File lib/Tioga/TeX_Text.rb, line 521
    def tex_xaxis_numeric_label
    end

tex_yaxis_numeric_label click to toggle source
tex_yaxis_numeric_label = a_string

The string for a numeric label is put in this TeX command string to be formatted. For example,

    $#1$

will give the numbers in math mode, while

    $\mathsf{#1}$

will show the label using the math sans-serif font. Alias for yaxis_numeric_label_tex.

    # File lib/Tioga/TeX_Text.rb, line 535
    def tex_yaxis_numeric_label
    end

text_shift_from_x_origin click to toggle source
text_shift_from_x_origin = a_float

Default value for “shift” in show_yaxis when “loc” is `AT_X_ORIGIN`.

    # File lib/Tioga/TeX_Text.rb, line 423
    def text_shift_from_x_origin
    end

text_shift_from_y_origin click to toggle source
text_shift_from_y_origin = a_float

Default value for “shift” in show_xaxis when “loc” is `AT_Y_ORIGIN`.

    # File lib/Tioga/TeX_Text.rb, line 431
    def text_shift_from_y_origin
    end

text_shift_on_bottom click to toggle source
text_shift_on_bottom = a_float

Default value for “shift” in `show_text` when “side” is `BOTTOM`.

    # File lib/Tioga/TeX_Text.rb, line 415
    def text_shift_on_bottom
    end

text_shift_on_left click to toggle source
text_shift_on_left = a_float

Default value for “shift” in `show_text` when “side” is `LEFT`.

    # File lib/Tioga/TeX_Text.rb, line 391
    def text_shift_on_left
    end

text_shift_on_right click to toggle source
text_shift_on_right = a_float

Default value for “shift” in `show_text` when “side” is `RIGHT`.

    # File lib/Tioga/TeX_Text.rb, line 399
    def text_shift_on_right
    end

text_shift_on_top click to toggle source
text_shift_on_top = a_float

Default value for “shift” in `show_text` when “side” is `TOP`.

    # File lib/Tioga/TeX_Text.rb, line 407
    def text_shift_on_top
    end