moved vu meter to seperate file

1 files changed, 220 insertions, 0 deletions

diff --git a/src/rhlibrary/vumeter_widget.go b/src/rhlibrary/vumeter_widget.go
new file mode 100644
index 0000000..323e826
--- /dev/null
+++ b/src/rhlibrary/vumeter_widget.go
@@ -0,0 +1,220 @@
+//
+//  rhlibrary
+//
+//  The Radio Helsinki Rivendell Library
+//
+//
+//  Copyright (C) 2016 Christian Pointner <equinox@helsinki.at>
+//
+//  This file is part of rhlibrary.
+//
+//  rhlibrary is free software: you can redistribute it and/or modify
+//  it under the terms of the GNU General Public License as published by
+//  the Free Software Foundation, either version 3 of the License, or
+//  any later version.
+//
+//  rhlibrary is distributed in the hope that it will be useful,
+//  but WITHOUT ANY WARRANTY; without even the implied warranty of
+//  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+//  GNU General Public License for more details.
+//
+//  You should have received a copy of the GNU General Public License
+//  along with rhlibrary. If not, see <http://www.gnu.org/licenses/>.
+//
+
+package main
+
+import (
+	"time"
+
+	"code.helsinki.at/rhrd-go/player"
+	"github.com/gotk3/gotk3/glib"
+	"github.com/gotk3/gotk3/gtk"
+)
+
+const (
+	meterDBFloor        float64 = 72 // -72 db is the lowest VU value
+	meterSegmentsGreen  float64 = 21
+	meterSegmentsOrange float64 = 3
+	meterSegmentsRed    float64 = 1
+	meterSegmentsTotal  float64 = meterSegmentsGreen + meterSegmentsOrange + meterSegmentsRed
+)
+
+var (
+	meterBarCSS *gtk.CssProvider
+)
+
+func init() {
+	var err error
+	if meterBarCSS, err = gtk.CssProviderNew(); err != nil {
+		panic(err.Error())
+	}
+	err = meterBarCSS.LoadFromData(`
+.level-bar {
+  -GtkLevelBar-min-block-width: 13;
+  -GtkLevelBar-min-block-height: 8;
+}
+.level-bar.trough {
+  border: 0;
+  padding: 0;
+  border-radius: 0;
+  background-image: unset;
+}
+.level-bar.fill-block.level-green {
+  border-color: #006600;
+  background-image: linear-gradient(to bottom, #36B736, #006600);
+}
+.level-bar.fill-block.level-orange {
+  border-color: #AE6600;
+  background-image: linear-gradient(to bottom, #FFAC36, #AE6600);
+}
+.level-bar.fill-block.level-red {
+  border-color: #AE0000;
+  background-image: linear-gradient(to bottom, #FF3636, #AE0000);
+}`)
+	if err != nil {
+		panic(err.Error())
+	}
+}
+
+type vuMeterLevel struct {
+	green  float64
+	orange float64
+	red    float64
+}
+
+func (lvl *vuMeterLevel) setLevel(valdb float64) {
+	val := valdb + meterDBFloor
+	if val < 0 {
+		val = 0
+	} else {
+		val = (val / meterDBFloor) * meterSegmentsTotal
+	}
+
+	lvl.green = val
+	lvl.orange = val - meterSegmentsGreen
+	lvl.red = lvl.orange - meterSegmentsOrange
+	if lvl.orange < 0 {
+		lvl.orange = 0
+	}
+	if lvl.red < 0 {
+		lvl.red = 0
+	}
+	return
+}
+
+type vuMeter struct {
+	green  *gtk.LevelBar
+	orange *gtk.LevelBar
+	red    *gtk.LevelBar
+}
+
+func createMeterBar(segments float64) (bar *gtk.LevelBar, err error) {
+	if bar, err = gtk.LevelBarNewForInterval(0, segments); err != nil {
+		return
+	}
+	bar.SetMode(gtk.LEVEL_BAR_MODE_DISCRETE)
+	bar.RemoveOffsetValue(gtk.LEVEL_BAR_OFFSET_LOW)
+	bar.RemoveOffsetValue(gtk.LEVEL_BAR_OFFSET_HIGH)
+
+	var sc *gtk.StyleContext
+	if sc, err = bar.GetStyleContext(); err != nil {
+		return
+	}
+	sc.AddProvider(meterBarCSS, 600) // TOOD: hardcoded value
+	return
+}
+
+func newVUMeter() (meter *vuMeter, err error) {
+	meter = &vuMeter{}
+	if meter.green, err = createMeterBar(meterSegmentsGreen); err != nil {
+		return
+	}
+	if meter.orange, err = createMeterBar(meterSegmentsOrange); err != nil {
+		return
+	}
+	if meter.red, err = createMeterBar(meterSegmentsRed); err != nil {
+		return
+	}
+
+	meter.green.AddOffsetValue("green", 0)
+	meter.orange.AddOffsetValue("orange", 0)
+	meter.red.AddOffsetValue("red", 0)
+
+	return
+}
+
+func (m *vuMeter) SetValue(lvl *vuMeterLevel) {
+	m.green.SetValue(lvl.green)
+	m.orange.SetValue(lvl.orange)
+	m.red.SetValue(lvl.red)
+}
+
+func addVUMeterGrid(frame *gtk.Frame, p *player.PlayerChan) (err error) {
+	var grid *gtk.Grid
+	if grid, err = gtk.GridNew(); err != nil {
+		return
+	}
+	grid.SetRowSpacing(3)
+
+	var left, right *vuMeter
+	if left, err = newVUMeter(); err != nil {
+		return
+	}
+	if right, err = newVUMeter(); err != nil {
+		return
+	}
+
+	p.AddUpdateHandler(func(length time.Duration, pos time.Duration, meter player.Meter, userdata interface{}) bool {
+		glib.IdleAdd(func() {
+			ch := len(meter)
+			lval := &vuMeterLevel{0, 0, 0}
+			rval := &vuMeterLevel{0, 0, 0}
+			if ch >= 2 {
+				lval.setLevel(meter[0].Peak)
+				rval.setLevel(meter[1].Peak)
+			} else if ch == 1 {
+				lval.setLevel(meter[0].Peak)
+				rval = lval
+			}
+			left.SetValue(lval)
+			right.SetValue(rval)
+		})
+		return true
+	}, nil)
+
+	grid.Attach(left.green, 1, 1, 1, 1)
+	grid.Attach(left.orange, 2, 1, 1, 1)
+	grid.Attach(left.red, 3, 1, 1, 1)
+	grid.Attach(right.green, 1, 2, 1, 1)
+	grid.Attach(right.orange, 2, 2, 1, 1)
+	grid.Attach(right.red, 3, 2, 1, 1)
+
+	frame.Add(grid)
+	return
+}
+
+func getVUMeterWidget(p *player.PlayerChan) (gtk.IWidget, error) {
+	frame, err := gtk.FrameNew("")
+	if err != nil {
+		return nil, err
+	}
+
+	var cp *gtk.CssProvider
+	if cp, err = gtk.CssProviderNew(); err != nil {
+		return nil, err
+	}
+	if err = cp.LoadFromData(".frame { padding: 3px; }"); err != nil {
+		return nil, err
+	}
+	var sc *gtk.StyleContext
+	if sc, err = frame.GetStyleContext(); err != nil {
+		return nil, err
+	}
+	sc.AddProvider(cp, 600) // TOOD: hardcoded value
+
+	if err = addVUMeterGrid(frame, p); err != nil {
+		return nil, err
+	}
+	return frame, nil
+}