meter.py

   1 # This file is part of jack_mixer
   2 #
   3 # Copyright (C) 2006 Nedko Arnaudov <nedko@arnaudov.name>
   4 #
   5 # This program is free software; you can redistribute it and/or modify
   6 # it under the terms of the GNU General Public License as published by
   7 # the Free Software Foundation; version 2 of the License
   8 #
   9 # This program is distributed in the hope that it will be useful,
  10 # but WITHOUT ANY WARRANTY; without even the implied warranty of
  11 # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12 # GNU General Public License for more details.
  13 #
  14 # You should have received a copy of the GNU General Public License
  15 # along with this program; if not, write to the Free Software
  16 # Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  17
  18 import logging
  19
  20 import cairo
  21 from gi.repository import Gtk
  22 from gi.repository import Gdk
  23
  24
  25 log = logging.getLogger(__name__)
  26
  27
  28 class MeterWidget(Gtk.DrawingArea):
  29     def __init__(self, scale):
  30         log.debug("Creating MeterWidget for scale %s", scale)
  31         super().__init__()
  32         self.scale = scale
  33         self.color_bg = Gdk.Color(0, 0, 0)
  34         self.color_value = None
  35         self.color_mark = Gdk.Color(int(65535 * 0.2), int(65535 * 0.2), int(65535 * 0.2))
  36         self.width = 0
  37         self.height = 0
  38         self.cache_surface = None
  39         self.min_width = 15
  40         self.preferred_width = 25
  41         self.preferred_height = 200
  42
  43         self.widen()
  44
  45         self.connect("draw", self.draw)
  46         self.connect("size-allocate", self.on_size_allocate)
  47
  48     def narrow(self):
  49         return self.widen(False)
  50
  51     def widen(self, flag=True):
  52         self.set_size_request(
  53             self.preferred_width if flag else self.min_width, self.preferred_height
  54         )
  55
  56     def set_color(self, color):
  57         self.color_value = color
  58         self.cache_surface = None
  59         self.invalidate_all()
  60
  61     def on_expose(self, widget, event):
  62         cairo_ctx = widget.window.cairo_create()
  63         # set a clip region for the expose event
  64         cairo_ctx.rectangle(event.area.x, event.area.y, event.area.width, event.area.height)
  65         cairo_ctx.clip()
  66
  67         self.draw(cairo_ctx)
  68
  69         return False
  70
  71     def on_size_allocate(self, widget, allocation):
  72         self.width = float(allocation.width)
  73         self.height = float(allocation.height)
  74         self.font_size = 10
  75         self.cache_surface = None
  76
  77     def invalidate_all(self):
  78         self.queue_draw_area(0, 0, int(self.width), int(self.height))
  79
  80     def draw_background(self, cairo_ctx):
  81         if not self.cache_surface:
  82             self.cache_surface = cairo.Surface.create_similar(
  83                 cairo_ctx.get_target(), cairo.CONTENT_COLOR, int(self.width), int(self.height)
  84             )
  85             cache_cairo_ctx = cairo.Context(self.cache_surface)
  86
  87             cache_cairo_ctx.set_source_rgba(0, 0, 0, 0)
  88             cache_cairo_ctx.rectangle(0, 0, self.width, self.height)
  89             cache_cairo_ctx.fill()
  90
  91             cache_cairo_ctx.set_source_rgba(0.2, 0.2, 0.2, 1)
  92             cache_cairo_ctx.select_font_face("Fixed")
  93             cache_cairo_ctx.set_font_size(self.font_size)
  94             glyph_width = self.font_size * 3 / 5  # avarage glyph ratio
  95
  96             for mark in self.scale.get_marks():
  97                 mark_position = int(self.height * (1 - mark.scale))
  98                 cache_cairo_ctx.move_to(0, mark_position)
  99                 cache_cairo_ctx.line_to(self.width, mark_position)
 100                 cache_cairo_ctx.stroke()
 101                 x_correction = self.width / 2 - glyph_width * len(mark.text) / 2
 102                 cache_cairo_ctx.move_to(x_correction, mark_position - 2)
 103                 cache_cairo_ctx.show_text(mark.text)
 104
 105         cairo_ctx.set_source_surface(self.cache_surface, 0, 0)
 106         cairo_ctx.paint()
 107
 108     def draw_value(self, cairo_ctx, value, x, width):
 109         if self.color_value is not None:
 110             cairo_ctx.set_source_rgb(
 111                 self.color_value.red / 65535.0,
 112                 self.color_value.green / 65535.0,
 113                 self.color_value.blue / 65535.0,
 114             )
 115         else:
 116             height = self.height
 117             gradient = cairo.LinearGradient(1, 1, width - 1, height - 1)
 118
 119             if self.scale.scale_id == "K20":
 120                 gradient.add_color_stop_rgb(0, 1, 0, 0)
 121                 gradient.add_color_stop_rgb(0.38, 1, 1, 0)
 122                 gradient.add_color_stop_rgb(0.5, 0, 1, 0)
 123                 gradient.add_color_stop_rgb(1, 0, 0, 1)
 124             elif self.scale.scale_id == "K14":
 125                 gradient.add_color_stop_rgb(0, 1, 0, 0)
 126                 gradient.add_color_stop_rgb(1 - self.scale.db_to_scale(-14), 1, 1, 0)
 127                 gradient.add_color_stop_rgb(1 - self.scale.db_to_scale(-24), 0, 1, 0)
 128                 gradient.add_color_stop_rgb(1, 0, 0, 1)
 129             else:
 130                 gradient.add_color_stop_rgb(0, 1, 0, 0)
 131                 gradient.add_color_stop_rgb(0.2, 1, 1, 0)
 132                 gradient.add_color_stop_rgb(1, 0, 1, 0)
 133
 134             cairo_ctx.set_source(gradient)
 135
 136         cairo_ctx.rectangle(x, self.height * (1 - value), width, self.height * value)
 137         cairo_ctx.fill()
 138
 139     def draw_peak(self, cairo_ctx, value, x, width):
 140         cairo_ctx.set_source_rgb(1, 1, 1)
 141         cairo_ctx.rectangle(x, self.height * (1 - value), width, 2.5)
 142         cairo_ctx.fill()
 143
 144     def set_scale(self, scale):
 145         self.scale = scale
 146         self.cache_surface = None
 147         self.invalidate_all()
 148
 149
 150 class MonoMeterWidget(MeterWidget):
 151     def __init__(self, scale):
 152         super().__init__(scale)
 153         self.value = 0.0
 154         self.pk = 0.0
 155         self.raw_value = 0.0
 156         self.raw_pk = 0.0
 157
 158     def draw(self, widget, cairo_ctx):
 159         self.draw_background(cairo_ctx)
 160         self.draw_value(cairo_ctx, self.value, self.width / 4.0, self.width / 2.0)
 161         self.draw_peak(cairo_ctx, self.pk, self.width / 4.0, self.width / 2.0)
 162
 163     def set_values(self, pk, value):
 164         if value == self.raw_value and pk == self.raw_pk:
 165             return
 166
 167         self.raw_value = value
 168         self.raw_pk = pk
 169         old_value = self.value
 170         old_pk = self.pk
 171         self.value = self.scale.db_to_scale(value)
 172         self.pk = self.scale.db_to_scale(pk)
 173
 174         if (abs(old_value - self.value) * self.height) > 0.01 or (
 175             abs(old_pk - self.pk) * self.height
 176         ) > 0.01:
 177             self.invalidate_all()
 178
 179
 180 class StereoMeterWidget(MeterWidget):
 181     def __init__(self, scale):
 182         super().__init__(scale)
 183         self.pk_left = 0.0
 184         self.pk_right = 0.0
 185
 186         self.left = 0.0
 187         self.right = 0.0
 188
 189         self.raw_left_pk = 0.0
 190         self.raw_right_pk = 0.0
 191
 192         self.raw_left = 0.0
 193         self.raw_right = 0.0
 194
 195     def draw(self, widget, cairo_ctx):
 196         self.draw_background(cairo_ctx)
 197         self.draw_value(cairo_ctx, self.left, self.width / 5.0, self.width / 5.0)
 198         self.draw_value(cairo_ctx, self.right, self.width / 5.0 * 3.0, self.width / 5.0)
 199         self.draw_peak(cairo_ctx, self.pk_left, self.width / 5.0, self.width / 5.0)
 200         self.draw_peak(cairo_ctx, self.pk_right, self.width / 5.0 * 3.0, self.width / 5.0)
 201
 202     def set_values(self, pk_l, pk_r, left, right):
 203         if (
 204             left == self.raw_left
 205             and right == self.raw_right
 206             and pk_l == self.raw_left_pk
 207             and pk_r == self.raw_right_pk
 208         ):
 209             return
 210
 211         self.raw_left = left
 212         self.raw_right = right
 213         self.raw_left_pk = pk_l
 214         self.raw_right_pk = pk_r
 215         old_left = self.left
 216         old_right = self.right
 217         old_pk_left = self.pk_left
 218         old_pk_right = self.pk_right
 219         self.left = self.scale.db_to_scale(left)
 220         self.right = self.scale.db_to_scale(right)
 221         self.pk_left = self.scale.db_to_scale(pk_l)
 222         self.pk_right = self.scale.db_to_scale(pk_r)
 223
 224         if (
 225             (abs(old_left - self.left) * self.height) > 0.01
 226             or (abs(old_right - self.right) * self.height) > 0.01
 227             or (abs(old_pk_left - self.pk_left) * self.height) > 0.01
 228             or (abs(old_pk_right - self.pk_right) * self.height) > 0.01
 229         ):
 230             self.invalidate_all()