Generating menus and buttons

Method

Library_gfx::get_menu_button_set()

Description

Creates an HTML menu bar by rendering button images with annotated text and basic interaction

Required Parameters

menu_buttons - An array of the buttons to generate. See &Library_gfx::get_button() for details.

Optional Parameters

separator - A string of html to be inserted between each generated button. images/opt_separator.gif is provided for this purpose.

template - Array of links to a LunpaCMS template when the button is clicked. If a scalar is passed, then the link is used for every button.

url - Array of links to an URL when the button is clicked. If a scalar is passed, then the link is used for every button.

Example

sub get_menu_button_set {

    my ($FORM, %params) = @_;

      my ($output, @menu_buttons);



        push(@menu_buttons, {title=>'Home',

                             template=>'index',

                             shadow_depth=>20,

                             shadow_x_offset=>0,

                             shadow_y_offset=>-2,

                             shadow_color=>'red'});



        push(@menu_buttons, {title=>"LunpaCMS\nDocumentation",

                             url=>'http://www.lunpacms.org/base.cgim?template=documentation_template_manager',

                             shadow_depth=>100,

                             shadow_color=>'black'});



        $output = &Library_gfx::get_menu_button_set($FORM,

                    menu_buttons=>\@menu_buttons,

                    separator=>"<img src=\"/images/opt_separator.gif\" width=2 height=\"100%\" alt=\"\">");



        return $output;

}

Individual buttons

Single buttons can be generated by calling &Library_gfx::get_button()

Method

Library_gfx::get_button()

Description

Generates annotated button images used for navigation links and in get_menu_button_set

Requried Parameters

title - Text to be annotated, is centred on the image by default. Escape characters such as \n and \t are rendered as expected.

Optional Parameters

template - Returns the image tag as a link to a LunpaCMS template.

url - Returns the image tag as a link to the specified URL

text_color - Fill color of the annotated text. This can either a word or HTML hex string, per ImageMagick's supported colour model specification.

blank_button - Background button image to annotate. images/opt.gif, images/opt_select.gif, and images/opt_hover.gif are provided for use with get_menu_button_set. To provide an "active" button for a menubar, use blank_button=<'opt_select.gif' or your own custom selected button template for the desired effect.

no_shadow - Set to 1 to disable rendering a drop shadow

shadow_color - Colour to render for the text drop shadow. Valid colours

shadow_depth - Integer level of blur to apply to the dropshadow (0 - 100).

shadow_x_offset - X-Pixel offset of the dropshadow. Defaults to 1.

shadow_y_offset - Y-Pixel offset of the dropshadow. Defaults to 2.

Example

$output = &Library_gfx::get_button($FORM,

      text=>"Pretty\nButtons",

      shadow_depth=>100,

      shadow_color=>'#636363',

      shadow_x_offset=>0,

      shadow_y_offset=>0);



return $output;

Annotating images

Images can be annotated with various fonts and colours with a transparent background using &Library_gfx::mixed_text_annotate(). The optimal geometries for a given font and text length can be determined using &Library_gfx::mixed_text_query_font_metric.

Method

Library_gfx::mixed_text_annotate

Description

Annotates an image with one or more fonts, colours, and geometries.

Required Parameters

image - An imagemagick image to annotate. use Image::Magick->new and Image::Magick->Read

text - String or array of strings to write to the image

font - Font or array of fonts to use for the annotation. These should be in the server's ImageMagick or LunpaCMS path.

font_size - Integer size of font sizes to render.

text_color - HTML or ImageMagick colour to render font in.

Optional Parameters

x_offset - Distance from origin of image.

y_offset - Distance from origin image.

gravity - Sets gravity for optional text shadow. Defaults to 'northwest'

font_directory - Path to search for true-type fonts in. Defaults to /usr/share/fonts/default/TrueType

no_shadow - Boolean to disable rendering text with a shadow.

shadow_color - Colour to render shadow. Defaults to 'grey'.

shadow_depth - Level of blurring for text shadow (0 - 100)

shadow_x_offset - Horizontal shadow offset (default 1)

shadow_y_offset - Vertical shadow offset (default 2)

Preparing to annotate an image

&Library_gfx::mixed_text_query_font_metric can help to annotate images with variable text length in a predictable and graceful way.

Method

Library_gfx::mixed_text_query_font_metric

Description

Returns metrics on the specified text and font, such as width, height, ascender, descender

Required Parameters

image - An imagemagick image to annotate. use Image::Magick->new and Image::Magick->Read

text - String or array of strings to write to the image

font - Font or array of fonts to use for the annotation. These should be in the server's ImageMagick or LunpaCMS path.

font_size - Integer size of font sizes to render.

text_color - HTML or ImageMagick colour to render font in.