Initial revision

2 files changed, 113 insertions, 0 deletions

diff --git a/Lib/lib-stdwin/StripChart.py b/Lib/lib-stdwin/StripChart.py
new file mode 100644
index 0000000..2021cc4
--- /dev/null
+++ b/Lib/lib-stdwin/StripChart.py
@@ -0,0 +1,67 @@
+# Module 'StripChart'
+
+
+import rect
+from Buttons import *
+from Resize import *
+
+
+class StripChart() = LabelAppearance(), NoReactivity(), NoResize():
+	#
+	def define(self, (win, bounds, scale)):
+		self.init_appearance(win, bounds)
+		self.init_reactivity()
+		self.init_resize()
+		self.ydata = []
+		self.scale = scale
+		self.resetbounds()
+		return self
+	#
+	def setbounds(self, bounds):
+		LabelAppearance.setbounds(self, bounds)
+		self.resetbounds()
+	#
+	def resetbounds(self):
+		(left, top), (right, bottom) = self.bounds
+		self.width = right-left
+		self.height = bottom-top
+		excess = len(self.ydata) - self.width
+		if excess > 0:
+			del self.ydata[:excess]
+		elif excess < 0:
+			while len(self.ydata) < self.width:
+				self.ydata.insert(0, 0)
+	#
+	def append(self, y):
+		self.ydata.append(y)
+		excess = len(self.ydata) - self.width
+		if excess > 0:
+			del self.ydata[:excess]
+			if not self.limbo:
+				self.win.scroll(self.bounds, (-excess, 0))
+		if not self.limbo:
+			(left, top), (right, bottom) = self.bounds
+			i = len(self.ydata)
+			area = (left+i-1, top), (left+i, bottom)
+			self.draw(self.win.begindrawing(), area)
+	#
+	def draw(self, (d, area)):
+		self.limbo = 0
+		area = rect.intersect(area, self.bounds)
+		if area = rect.empty:
+			return
+		d.cliprect(area)
+		d.erase(self.bounds)
+		(a_left, a_top), (a_right, a_bottom) = area
+		(left, top), (right, bottom) = self.bounds
+		height = bottom - top
+		i1 = a_left - left
+		i2 = a_right - left
+		for i in range(max(0, i1), min(len(self.ydata), i2)):
+			split = bottom-self.ydata[i]*height/self.scale
+			d.paint((left+i, split), (left+i+1, bottom))
+		if not self.enabled:
+			self.flipenable(d)
+		if self.hilited:
+			self.fliphilite(d)
+		d.noclip()
diff --git a/Lib/lib-stdwin/VUMeter.py b/Lib/lib-stdwin/VUMeter.py
new file mode 100644
index 0000000..65c018b
--- /dev/null
+++ b/Lib/lib-stdwin/VUMeter.py
@@ -0,0 +1,46 @@
+# Module VUMeter
+
+import audio
+from StripChart import StripChart
+
+K = 1024
+Rates = [0, 32*K, 16*K, 8*K]
+
+class VUMeter() = StripChart():
+	#
+	# Override define() and timer() methods
+	#
+	def define(self, (win, bounds)):
+		self = StripChart.define(self, (win, bounds, 128))
+		self.sampling = 0
+		self.rate = 3
+		self.enable(0)
+		return self
+	#
+	def timer(self):
+		if self.sampling:
+			chunk = audio.wait_recording()
+			self.sampling = 0
+			nums = audio.chr2num(chunk)
+			ampl = max(abs(min(nums)), abs(max(nums)))
+			self.append(ampl)
+		if self.enabled and not self.sampling:
+			audio.setrate(self.rate)
+			size = Rates[self.rate]/10
+			size = size/48*48
+			audio.start_recording(size)
+			self.sampling = 1
+		if self.sampling:
+			self.win.settimer(1)
+	#
+	# New methods: start() and stop()
+	#
+	def stop(self):
+		if self.sampling:
+			chunk = audio.stop_recording()
+			self.sampling = 0
+		self.enable(0)
+	#
+	def start(self):
+		self.enable(1)
+		self.timer()