TextLayout Class

Inheritance diagram of TextLayout

class TextLayout(document, width=None, height=None, multiline=False, dpi=None, batch=None, group=None, wrap_lines=True)

Lay out and display documents.

This class is intended for displaying documents that do not change regularly – any change will cost some time to lay out the complete document again and regenerate all vertex lists.

The benefit of this class is that texture state is shared between all layouts of this class. The time to draw one TextLayout may be roughly the same as the time to draw one IncrementalTextLayout; but drawing ten TextLayout objects in one batch is much faster than drawing ten incremental or scrollable text layouts.

Label and HTMLLabel provide a convenient interface to this class.

Variables:
  • content_width – Calculated width of the text in the layout. This may overflow the desired width if word-wrapping failed.
  • content_height – Calculated height of the text in the layout.
  • top_group – Top-level rendering group.
  • background_group – Rendering group for background color.
  • foreground_group – Rendering group for glyphs.
  • foreground_decoration_group – Rendering group for glyph underlines.

Constructor:

__init__(document, width=None, height=None, multiline=False, dpi=None, batch=None, group=None, wrap_lines=True)

Create a text layout.

Parameters:
  • document (AbstractDocument) – Document to display.
  • width (int) – Width of the layout in pixels, or None
  • height (int) – Height of the layout in pixels, or None
  • multiline (bool) – If False, newline and paragraph characters are ignored, and text is not word-wrapped. If True, text is wrapped only if the wrap_lines is True.
  • dpi (float) – Font resolution; defaults to 96.
  • batch (Batch) – Optional graphics batch to add this layout to.
  • group (Group) – Optional rendering group to parent all groups this text layout uses. Note that layouts with different rendered simultaneously in a batch.
  • wrap_lines (bool) – If True and multiline is True, the text is word-wrapped using the specified width.

Methods:

begin_update() Indicate that a number of changes to the layout or document are about to occur.
delete() Remove this layout from its batch.
draw() Draw this text layout.
end_update() Perform pending layout changes since begin_update.
on_delete_text(start, end) Event handler for AbstractDocument.on_delete_text.
on_insert_text(start, text) Event handler for AbstractDocument.on_insert_text.
on_style_text(start, end, attributes) Event handler for AbstractDocument.on_style_text.

Attributes:

anchor_x Horizontal anchor alignment.
anchor_y Vertical anchor alignment.
background_group A group with partial order.
content_valign Vertical alignment of content within larger layout box.
document
dpi Get DPI used by this layout.
foreground_decoration_group Rendering group for decorative elements (e.g., glyph underlines) in all text layouts.
foreground_group Rendering group for foreground elements (glyphs) in all text layouts.
height Height of the layout.
multiline Set if multiline layout is enabled.
top_group Type: TextLayoutGroup
width Width of the layout.
x X coordinate of the layout.
y Y coordinate of the layout.

Methods

TextLayout.begin_update()

Indicate that a number of changes to the layout or document are about to occur.

Changes to the layout or document between calls to begin_update and end_update do not trigger any costly relayout of text. Relayout of all changes is performed when end_update is called.

Note that between the begin_update and end_update calls, values such as content_width and content_height are undefined (i.e., they may or may not be updated to reflect the latest changes).

TextLayout.delete()

Remove this layout from its batch.

TextLayout.draw()

Draw this text layout.

Note that this method performs very badly if a batch was supplied to the constructor. If you add this layout to a batch, you should ideally use only the batch’s draw method.

TextLayout.end_update()

Perform pending layout changes since begin_update.

See begin_update.

TextLayout.on_delete_text(start, end)

Event handler for AbstractDocument.on_delete_text.

The event handler is bound by the text layout; there is no need for applications to interact with this method.

TextLayout.on_insert_text(start, text)

Event handler for AbstractDocument.on_insert_text.

The event handler is bound by the text layout; there is no need for applications to interact with this method.

TextLayout.on_style_text(start, end, attributes)

Event handler for AbstractDocument.on_style_text.

The event handler is bound by the text layout; there is no need for applications to interact with this method.

Attributes

TextLayout.anchor_x

Horizontal anchor alignment.

This property determines the meaning of the x coordinate. It is one of the enumerants:

"left" (default)
The X coordinate gives the position of the left edge of the layout.
"center"
The X coordinate gives the position of the center of the layout.
"right"
The X coordinate gives the position of the right edge of the layout.

For the purposes of calculating the position resulting from this alignment, the width of the layout is taken to be width if multiline is True and wrap_lines is True, otherwise content_width.

Type:str
TextLayout.anchor_y

Vertical anchor alignment.

This property determines the meaning of the y coordinate. It is one of the enumerants:

"top"
The Y coordinate gives the position of the top edge of the layout.
"center"
The Y coordinate gives the position of the center of the layout.
"baseline"
The Y coordinate gives the position of the baseline of the first line of text in the layout.
"bottom" (default)
The Y coordinate gives the position of the bottom edge of the layout.

For the purposes of calculating the position resulting from this alignment, the height of the layout is taken to be the smaller of height and content_height.

See also content_valign.

Type:str
TextLayout.background_group = OrderedGroup(0)
TextLayout.content_valign

Vertical alignment of content within larger layout box.

This property determines how content is positioned within the layout box when content_height is less than height. It is one of the enumerants:

top (default)
Content is aligned to the top of the layout box.
center
Content is centered vertically within the layout box.
bottom
Content is aligned to the bottom of the layout box.

This property has no effect when content_height is greater than height (in which case the content is aligned to the top) or when height is None (in which case there is no vertical layout box dimension).

Type:str
TextLayout.document
TextLayout.dpi

Get DPI used by this layout.

Read-only.

Type:float
TextLayout.foreground_decoration_group = TextLayoutForegroundDecorationGroup(2)
TextLayout.foreground_group = TextLayoutForegroundGroup(1)
TextLayout.height

Height of the layout.

Type:int
TextLayout.multiline

Set if multiline layout is enabled.

If multiline is False, newline and paragraph characters are ignored and text is not word-wrapped. If True, the text is word-wrapped only if the wrap_lines is True.

Type:bool
TextLayout.top_group = <pyglet.text.layout.TextLayoutGroup object at 0x7ff49523a350>
TextLayout.width

Width of the layout.

This property has no effect if multiline is False or wrap_lines is False.

Type:int
TextLayout.x

X coordinate of the layout.

See also anchor_x.

Type:int
TextLayout.y

Y coordinate of the layout.

See also anchor_y.

Type:int

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