meter.py

   1 #!/usr/bin/env python
   2 #
   3 # This file is part of jack_mixer
   4 #
   5 # Copyright (C) 2006 Nedko Arnaudov <nedko@arnaudov.name>
   6 #
   7 # This program is free software; you can redistribute it and/or modify
   8 # it under the terms of the GNU General Public License as published by
   9 # the Free Software Foundation; version 2 of the License
  10 #
  11 # This program is distributed in the hope that it will be useful,
  12 # but WITHOUT ANY WARRANTY; without even the implied warranty of
  13 # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14 # GNU General Public License for more details.
  15 #
  16 # You should have received a copy of the GNU General Public License
  17 # along with this program; if not, write to the Free Software
  18 # Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  19
  20 import gtk
  21
  22 class meter(gtk.DrawingArea):
  23     def __init__(self, scale):
  24         gtk.DrawingArea.__init__(self)
  25
  26         self.scale = scale
  27
  28         self.connect("expose-event", self.on_expose)
  29         self.connect("size-request", self.on_size_request)
  30         self.connect("size_allocate", self.on_size_allocate)
  31
  32         self.color_bg = gtk.gdk.Color(0,0,0)
  33         self.color_value = gtk.gdk.Color(int(65535 * 0.8), int(65535 * 0.7), 0)
  34         self.color_mark = gtk.gdk.Color(int(65535 * 0.2), int(65535 * 0.2), int(65535 * 0.2))
  35         self.width = 0
  36         self.height = 0
  37
  38     def on_expose(self, widget, event):
  39         cairo_ctx = widget.window.cairo_create()
  40
  41         # set a clip region for the expose event
  42         cairo_ctx.rectangle(event.area.x, event.area.y, event.area.width, event.area.height)
  43         cairo_ctx.clip()
  44
  45         self.draw(cairo_ctx)
  46
  47         return False
  48
  49     def on_size_allocate(self, widget, allocation):
  50         #print allocation.x, allocation.y, allocation.width, allocation.height
  51         self.width = float(allocation.width)
  52         self.height = float(allocation.height)
  53         self.font_size = 10
  54
  55     def on_size_request(self, widget, requisition):
  56         #print "size-request, %u x %u" % (requisition.width, requisition.height)
  57         requisition.width = 20
  58         return
  59
  60     def invalidate_all(self):
  61         self.queue_draw_area(0, 0, int(self.width), int(self.height))
  62
  63     def draw_background(self, cairo_ctx):
  64         cairo_ctx.set_source_color(self.color_bg)
  65         cairo_ctx.rectangle(0, 0, self.width, self.height)
  66         cairo_ctx.fill()
  67
  68         cairo_ctx.set_source_color(self.color_mark)
  69         cairo_ctx.select_font_face("Fixed")
  70         cairo_ctx.set_font_size(self.font_size)
  71         glyph_width = self.font_size * 3 / 5 # avarage glyph ratio
  72         for mark in self.scale.get_marks():
  73             mark_position = int(self.height * (1 - mark.scale))
  74             cairo_ctx.move_to(0, mark_position)
  75             cairo_ctx.line_to(self.width, mark_position)
  76             cairo_ctx.stroke()
  77             x_correction = self.width / 2 - glyph_width * len(mark.text) / 2
  78             cairo_ctx.move_to(x_correction, mark_position - 2)
  79             cairo_ctx.show_text(mark.text)
  80
  81     def draw_value(self, cairo_ctx, value, x, width):
  82         #return
  83         cairo_ctx.set_source_color(self.color_value)
  84         cairo_ctx.rectangle(x, self.height * (1 - value), width, self.height * value)
  85         cairo_ctx.fill()
  86
  87     def set_scale(self, scale):
  88         self.scale = scale
  89         self.invalidate_all()
  90
  91 class mono(meter):
  92     def __init__(self, scale):
  93         meter.__init__(self, scale)
  94         self.value = 0.0
  95
  96     def draw(self, cairo_ctx):
  97         self.draw_background(cairo_ctx)
  98         self.draw_value(cairo_ctx, self.value, self.width/4.0, self.width/2.0)
  99
 100     def set_value(self, value):
 101         if value != self.value:
 102             self.value = self.scale.db_to_scale(value)
 103             self.invalidate_all()
 104
 105 class stereo(meter):
 106     def __init__(self, scale):
 107         meter.__init__(self, scale)
 108         self.left = 0.0
 109         self.right = 0.0
 110
 111     def draw(self, cairo_ctx):
 112         self.draw_background(cairo_ctx)
 113         self.draw_value(cairo_ctx, self.left, self.width/5.0, self.width/5.0)
 114         self.draw_value(cairo_ctx, self.right, self.width/5.0 * 3.0, self.width/5.0)
 115
 116     def set_values(self, left, right):
 117         if left != self.left or right != self.right:
 118             self.left = self.scale.db_to_scale(left)
 119             self.right = self.scale.db_to_scale(right)
 120             self.invalidate_all()