Add zoom animation to icon_widget presses

adafruit_displayio_layout/widgets/icon_widget.py

@@ -21,27 +21,41 @@
   https://github.com/adafruit/circuitpython/releases
 
 """
-
-
+import gc
+import time
 import terminalio
-from displayio import TileGrid, OnDiskBitmap, ColorConverter
+import bitmaptools
+from displayio import TileGrid, OnDiskBitmap, ColorConverter, Bitmap, Palette
 import adafruit_imageload
 from adafruit_display_text import bitmap_label
 from adafruit_displayio_layout.widgets.control import Control
 from adafruit_displayio_layout.widgets.widget import Widget
+from adafruit_displayio_layout.widgets.easing import quadratic_easeout as easein
+from adafruit_displayio_layout.widgets.easing import quadratic_easein as easeout
 
 
 class IconWidget(Widget, Control):
 
     """
     A touch enabled widget that holds an icon image loaded with
-    adafruit_imageload and a text label centered beneath it.
+    adafruit_imageload and a text label centered beneath it. Includes optional
+    animation to increase the icon size when pressed.
 
-    :param string label_text: the text that will be shown beneath the icon image.
-    :param string icon: the filepath of the bmp image to be used as the icon.
-    :param boolean on_disk: if True use OnDiskBitmap instead of imageload.
+    :param displayio.Display display: the display where the ``IconWidget`` is displayed,
+     used for handling animations.
+    :param str label_text: the text that will be shown beneath the icon image.
+    :param str icon: the filepath of the bmp image to be used as the icon.
+    :param bool on_disk: if True use OnDiskBitmap instead of imageload.
      This can be helpful to save memory. Defaults to False
 
+    :param float max_scale: the maximum zoom during animation, set 1.0 for no animation
+     a value of 1.4 is a good starting point (default: 1.0, no animation),
+     ``max_scale`` must be between 1.0 and 1.5.
+    :param float max_angle: the maximum degrees of rotation during animation, positive values
+     are clockwise, set 0 for no rotation, in degrees (default: 0 degrees)
+    :param float animation_time: the time for the animation in seconds, set to 0.0 for
+     no animation, a value of 0.15 is a good starting point (default: 0.0 seconds)
+
     :param int x: x location the icon widget should be placed. Pixel coordinates.
     :param int y: y location the icon widget should be placed. Pixel coordinates.
     :param anchor_point: (X,Y) values from 0.0 to 1.0 to define the anchor point relative to the
@@ -52,19 +66,47 @@ class IconWidget(Widget, Control):
     :param int max_size: (Optional) this will get passed through to the
      displayio.Group constructor. If omitted we default to
      grid_size width * grid_size height to make room for all (1, 1) sized cells.
-
     """
 
-    def __init__(self, label_text, icon, on_disk=False, **kwargs):
-        super().__init__(**kwargs)
+    # pylint: disable=bad-super-call, too-many-instance-attributes, too-many-locals
+    # pylint: disable=too-many-arguments, unused-argument
+
+    _max_scale = 1.5
+    _max_pixels = 80
+    _max_color_depth = 512
+    _zoom_bitmap = Bitmap(
+        round(_max_scale * _max_pixels),
+        round(_max_scale * _max_pixels),
+        _max_color_depth,
+    )
+    _zoom_palette = Palette(_max_color_depth)
+
+    def __init__(
+        self,
+        display,
+        label_text,
+        icon,
+        on_disk=False,
+        max_scale=1.0,
+        max_angle=8,
+        animation_time=0.0,
+        **kwargs,
+    ):
+
+        super().__init__(**kwargs)  # initialize superclasses
+        super(Control, self).__init__()
+
+        self.display = display
+        self._icon = icon
 
         if on_disk:
             self._file = open(icon, "rb")
             image = OnDiskBitmap(self._file)
             tile_grid = TileGrid(image, pixel_shader=ColorConverter())
         else:
-            image, palette = adafruit_imageload.load(icon)
+            image, palette = adafruit_imageload.load(self._icon)
             tile_grid = TileGrid(image, pixel_shader=palette)
+
         self.append(tile_grid)
         _label = bitmap_label.Label(
             terminalio.FONT,
@@ -81,6 +123,27 @@ def __init__(self, label_text, icon, on_disk=False, **kwargs):
             image.height + _label.bounding_box[3],
         )
 
+        # verify the animation settings
+        self._start_scale = 1.0
+
+        # constrain maximum_scaling between 1.0 and 1.5
+        self._max_scale = min(max(1.0, max_scale), IconWidget._max_scale)
+        if max_scale == 1.0:  # no animation
+            self._animation_time = 0
+        else:
+            self._animation_time = animation_time  # in seconds
+        self._end_scale = max_scale
+
+        self._angle = (max_angle / 360) * 2 * 3.14  # 5 degrees, convert to radians
+
+        # define zoom attributes
+        self._zoom_color_depth = None
+        self._zoom_palette = None
+        self._zoom_bitmap = None
+        self._zoom_tilegrid = None
+
+        self.value = False  # initial value
+
     def contains(self, touch_point):  # overrides, then calls Control.contains(x,y)
 
         """Checks if the IconWidget was touched.  Returns True if the touch_point is
@@ -97,3 +160,111 @@ def contains(self, touch_point):  # overrides, then calls Control.contains(x,y)
         touch_y = touch_point[1] - self.y
 
         return super().contains((touch_x, touch_y, 0))
+
+    def zoom_animation(self, touch_point):
+        """Performs zoom animation when pressed.
+
+        :param touch_point: x,y location of the screen, converted to local coordinates.
+        :type touch_point: Tuple[x,y]
+        :return: None
+        """
+
+        self.value = True
+
+        if self._animation_time > 0:
+            ###
+            ## Update the zoom palette and bitmap buffers and append the tilegrid
+            ###
+
+            _image, _palette = adafruit_imageload.load(self._icon)
+
+            # copy the image palette, add a transparent color at the end
+            for i, color in enumerate(_palette):
+                IconWidget._zoom_palette[i] = color
+            IconWidget._zoom_palette[len(IconWidget._zoom_palette) - 1] = 0x000000
+            IconWidget._zoom_palette.make_transparent(len(IconWidget._zoom_palette) - 1)
+
+            # create the zoom bitmap larger than the original image to allow for zooming
+            IconWidget._zoom_bitmap.fill(
+                len(IconWidget._zoom_palette) - 1
+            )  # transparent fill
+            IconWidget._zoom_bitmap.blit(
+                (IconWidget._zoom_bitmap.width - _image.width) // 2,
+                (IconWidget._zoom_bitmap.height - _image.height) // 2,
+                _image,
+            )  # blit the image into the center of the zoom_bitmap
+
+            # place zoom_bitmap at same location as image
+            self._zoom_tilegrid = TileGrid(
+                IconWidget._zoom_bitmap, pixel_shader=IconWidget._zoom_palette
+            )
+            self._zoom_tilegrid.x = -(IconWidget._zoom_bitmap.width - _image.width) // 2
+            self._zoom_tilegrid.y = (
+                -(IconWidget._zoom_bitmap.height - _image.height) // 2
+            )
+            self.append(self._zoom_tilegrid)  # add to the self group.
+
+            # Animation: zoom larger
+            start_time = time.monotonic()
+            while True:
+                elapsed_time = time.monotonic() - start_time
+                position = min(
+                    1.0, easein(elapsed_time / self._animation_time)
+                )  # fractional position
+                bitmaptools.rotozoom(
+                    dest_bitmap=IconWidget._zoom_bitmap,
+                    ox=IconWidget._zoom_bitmap.width // 2,
+                    oy=IconWidget._zoom_bitmap.height // 2,
+                    source_bitmap=_image,
+                    px=_image.width // 2,
+                    py=_image.height // 2,
+                    scale=self._start_scale
+                    + position * (self._end_scale - self._start_scale),
+                    angle=position * self._angle / 2,
+                )
+                self.display.refresh()
+                if elapsed_time > self._animation_time:
+                    break
+            del _image
+            del _palette
+            gc.collect()
+
+    def zoom_out_animation(self, touch_point):
+        """Performs un-zoom animation when released.
+
+        :param touch_point: x,y location of the screen, converted to local coordinates.
+        :type touch_point: Tuple[x,y]
+        :return: None
+        """
+
+        _image, _palette = adafruit_imageload.load(self._icon)
+
+        if (self._animation_time > 0) and self.value:
+            # Animation: shrink down to the original size
+            start_time = time.monotonic()
+            while True:
+                elapsed_time = time.monotonic() - start_time
+                position = max(0.0, easeout(1 - (elapsed_time / self._animation_time)))
+                IconWidget._zoom_bitmap.fill(len(IconWidget._zoom_palette) - 1)
+                bitmaptools.rotozoom(
+                    dest_bitmap=IconWidget._zoom_bitmap,
+                    ox=IconWidget._zoom_bitmap.width // 2,
+                    oy=IconWidget._zoom_bitmap.height // 2,
+                    source_bitmap=_image,
+                    px=_image.width // 2,
+                    py=_image.height // 2,
+                    scale=self._start_scale
+                    + position * (self._end_scale - self._start_scale),
+                    angle=position * self._angle / 2,
+                )
+                self.display.refresh()
+                if elapsed_time > self._animation_time:
+                    break
+
+            # clean up the zoom display elements
+            self.pop(-1)  # remove self from the group
+            del _image
+            del _palette
+            gc.collect()
+
+        self.value = False

docs/conf.py

@@ -34,6 +34,7 @@
     "terminalio",
     "adafruit_imageload",
     "adafruit_display_text",
+    "bitmaptools",
 ]