cairo_framework.py

# Some cairo magic, thanks goes to Michael Urman for tutorials

import gtk
import cairo
import os

class DrawingArea(gtk.DrawingArea):
    __gsignals__ = { "expose-event": "override" }
    def do_expose_event(self, event):

        cr = self.window.cairo_create()

        cr.rectangle(event.area.x, event.area.y,
                event.area.width, event.area.height)
        cr.clip()

        self.draw(cr, *self.window.get_size())
	
class Pad(DrawingArea):
		
	def Set_Parameters(self,tablet=None):
		self.Tablet = tablet
		if self.Tablet:
			self.ButtonMap = self.Tablet.Buttons
			self.Image = "images/pad/" + self.Tablet.Model + ".png"
			try:
				os.stat(self.Image)
			except:
				print ("No image for %s pad" % self.Tablet.Model)
				self.Image = ""
			
		else:
			self.ButtonMap = []
			self.Image = ""
		
	def draw(self, cr, width, height):

		cr.set_source_rgb(0.5, 0.5, 0.5)
		cr.rectangle(0, 0, width, height)
		cr.fill()

		if self.Image:
			# Draw background image
			cr.set_source_surface(cairo.ImageSurface.create_from_png(self.Image))
			cr.paint()		

		if self.ButtonMap != []:
			# Paint on buttons
			cr.select_font_face("Sans",cairo.FONT_SLANT_NORMAL,cairo.FONT_WEIGHT_BOLD)
			cr.set_font_size(18)
			
			for button in self.ButtonMap:
				cr.set_source_rgba(1,1,1,1)
				choffset = len(str(button.Number)) * 6
				cr.move_to(int((button.X1+button.X2)/2)-choffset,int((button.Y1+button.Y2)/2)+6)
				cr.show_text (str(button.Number))
				cr.set_source_rgba(1.0, 1.0, 1.0,0.4)
				cr.rectangle(button.X1, button.Y1, button.X2-button.X1, button.Y2-button.Y1)
				cr.stroke()
		else:
			cr.select_font_face("Sans",cairo.FONT_SLANT_NORMAL,cairo.FONT_WEIGHT_BOLD)
			cr.set_font_size(10)
			cr.set_source_rgba(1,1,1,1)
			cr.move_to(0,16)
			cr.show_text ("No preview available for this model.")