# HG changeset patch
# User Jeremy Thurgood <firxen@gmail.com>
# Date 1328974895 -7200
# Node ID 1eb1537173ef960e029814b522f4ba95b9f062e3
# Parent  4e9178215e7509d81b5ab116a464cb5ed6177580
Add some image transforms.

diff -r 4e9178215e75 -r 1eb1537173ef pyntnclick/image_transforms.py
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/pyntnclick/image_transforms.py	Sat Feb 11 17:41:35 2012 +0200
@@ -0,0 +1,63 @@
+"""Transforms to apply to images when they're loaded."""
+
+from pygame.transform import rotate
+from pygame.locals import BLEND_RGBA_MULT, SRCALPHA
+from pygame.surface import Surface
+
+
+class Transform(object):
+
+    def __init__(self, func, *args):
+        self._func = func
+        self._args = args
+
+    def __call__(self, image):
+        return self._func(image, *self._args)
+
+    def __hash__(self):
+        return hash((id(self._func), self._args))
+
+    def __eq__(self, other):
+        return (self._func is other._func) and self._args == other._args
+
+    def __repr__(self):
+        return "<%s args=%r>" % (self.__class__.__name__, self._args)
+
+
+# transform that does nothing
+NULL = Transform(lambda x: x)
+
+# base rotation transforms
+R90 = Transform(rotate, 90)
+R180 = Transform(rotate, 180)
+R270 = Transform(rotate, -90)
+
+
+# overlays
+class Overlay(Transform):
+    """Overlay another image on top of the given one."""
+
+    def __init__(self, resources, image_name_fragments, blend=0):
+        super(Overlay, self).__init__(
+            self.overlay, resources, image_name_fragments, blend)
+
+    def overlay(self, image, resources, image_name_fragments, blend):
+        image = image.copy()
+        overlay = resources.load_image(image_name_fragments)
+        image.blit(overlay, (0, 0), None, blend)
+        return image
+
+
+# colour overlays
+class Colour(Transform):
+    """Overlay an image with a colour."""
+
+    def __init__(self, colour, blend=BLEND_RGBA_MULT):
+        super(Colour, self).__init__(self.colour, colour, blend)
+
+    def colour(self, image, colour, blend):
+        image = image.copy()
+        overlay = Surface(image.get_size(), SRCALPHA, image)
+        overlay.fill(colour)
+        image.blit(overlay, (0, 0), None, blend)
+        return image
diff -r 4e9178215e75 -r 1eb1537173ef pyntnclick/resources.py
--- a/pyntnclick/resources.py	Sat Feb 11 17:38:57 2012 +0200
+++ b/pyntnclick/resources.py	Sat Feb 11 17:41:35 2012 +0200
@@ -66,8 +66,7 @@
         image name out of several fragments.
 
         The `transforms` param may contain transforms, which modify an image
-        in-place to apply various effects. TODO: Implement transforms
-        somewhere, so this becomes useful.
+        in-place to apply various effects.
 
         The `basedir` param defaults to 'images', but may be overriden to load
         images from other places. ('icons', for example.)
@@ -90,7 +89,7 @@
             self._image_cache[image_path] = image
         image = self._image_cache[image_path]
 
-        # Apply any mutators we're given.
+        # Apply any transforms we're given.
         for transform in transforms:
             image = transform(image)
         self._transformed_image_cache[key] = image