Add curved outputs

- Prolong life, different fades
- Wrap current output

1 files changed, 29 insertions, 1 deletions

diff --git a/blc/output.py b/blc/output.py
index 147ea6b..dfe9a3d 100644
--- a/blc/output.py
+++ b/blc/output.py
@@ -1,9 +1,10 @@
 """DMX module.
 
-Defines a generic interface for a DMX interface.
+Defines a generic interface for a DMX interface along with some utility interfaces.
 """
 
 from abc import ABC, abstractmethod
+import array
 
 class LightingOutput(ABC):
     """Generic lighting interface."""
@@ -40,3 +41,30 @@ class ChainedLightingOutput(LightingOutput):
     def __init__(self, *outputs):
         self.outputs = outputs
         self.trans_time = min((i.trans_time for i in outputs))
+
+class CurvedOutput(LightingOutput):
+    """Class for using a custom dimmer curve. 
+
+    The given f may be a callable (which must accept integers from 0--255, inclusive) or a list 
+    of 256 values, with f[0] representing the output at 0 and f[255] the output at 255. 
+    """
+    def set_values(self, values):
+        self.output.set_values(map(self.map, values))
+
+    def __init__(self, output, f=lambda x: x):
+        self.output = output
+        self.trans_time = output.trans_time
+        if callable(f):
+            self.curve = array.array('B', (f(i) for i in range(256)))
+        else:
+            self.curve = array.array('B', f)
+        self.map = lambda a: (a[0], self.curve[a[1]],)
+
+## Enforce that all lights remain on at 5%
+LINEAR_PREHEAT = lambda x: int(243/255*x + 12)
+
+## Enforce that all lights stay below 95%
+LINEAR_TOPSET = lambda x: int(243/255*x)
+
+## Enforce that all lights remain in the 5%--95% range
+LINEAR_BOTH = lambda x: int(231/255*x + 12)