In this article we will see how we can ensure line is visible in incremental text layout object in PYGLET module in python. Pyglet is easy to use but powerful library for developing visually rich GUI applications like games, multimedia etc. A window is a “heavyweight” object occupying operating system resources. Windows may appear as floating regions or can be set to fill an entire screen (fullscreen). Incremental text layout displays text which is suitable for interactive editing and/or scrolling large documents. Unlike TextLayout and ScrollableTextLayout, this class generates vertex lists only for lines of text that are visible. As the document is scrolled, vertex lists are deleted and created as appropriate to keep video memory usage to a minimum and improve rendering speed. Ensure line visible adjust view_y so that the line with the given index is visible.
We can create a window and incremental text layout with the help of commands given below
# creating a window window = pyglet.window.Window(width, height, title) # creating a in layout = pyglet.text.layout.IncrementalTextLayout(document, width, height)
In order to create window we use ensure_line_visible method
Syntax : layout.ensure_line_visible(line)
Argument : It takes integer as argument
Return : It returns None
Below is the implementation
Python3
# importing pyglet moduleimport pygletimport pyglet.window.key # width of windowwidth = 500 # height of windowheight = 500 # caption i.e title of the windowtitle = "Geeksforneveropen" # creating a windowwindow = pyglet.window.Window(width, height, title) # text text = "neveropen Learn and Grow, Portal for Geeks" # batch objectbatch = pyglet.graphics.Batch() # creating a formatted document# unlike unformatted document it is formatteddocument = pyglet.text.document.FormattedDocument(text) # setting style to the documentdocument.set_style(0, len(document.text), dict(font_name ='Arial', font_size = 16, color =(255, 255, 255, 255))) # creating a incremental text layoutlayout = pyglet.text.layout.IncrementalTextLayout(document, 400, 350, multiline = True, batch = batch) # creating a caretcaret = pyglet.text.caret.Caret(layout, color =(150, 255, 150)) # caret to window push handlerswindow.push_handlers(caret) # setting caret stylecaret.set_style(dict(font_name ="Arial")) # on draw event@window.eventdef on_draw(): # clear the window window.clear() # draw the batch batch.draw() # caret to window push handlers window.push_handlers(caret) # key press event @window.eventdef on_key_press(symbol, modifier): # key "C" get press if symbol == pyglet.window.key.C: # closing the window # window.close() pass # image for iconimg = pyglet.resource.image("gfg.png")# setting image as iconwindow.set_icon(img)# ensuring line visible property for index 1layout.ensure_line_visible(1) # start running the applicationpyglet.app.run() |
Output :
