Gadget minimum height/width is now 0 from 1.

src/batgrl/gadgets/box_image.py

@@ -203,13 +203,18 @@ def alpha(self, alpha: float):
         self._image.alpha = alpha
 
     @property
-    def path(self):
+    def path(self) -> Path | None:
         """Path to image."""
         return self._path
 
     @path.setter
-    def path(self, value):
-        self._path = value
+    def path(self, path: Path | None):
+        self._path: Path | None = path
+
+        if path is None:
+            self._otexture = np.zeros((1, 1, 3), dtype=np.uint8)
+        else:
+            self._otexture = cv2.imread(str(path.absolute()), cv2.IMREAD_COLOR)
         self._load_texture()
 
     def on_size(self):
@@ -219,11 +224,11 @@ def on_size(self):
 
     def _load_texture(self):
         h, w = self.size
-        canvas = self._image.canvas
-
-        img = cv2.imread(str(self.path.absolute()), cv2.IMREAD_COLOR)
-        img_bgr = cv2.resize(img, (2 * w, 2 * h))
+        if h == 0 or w == 0:
+            return
 
+        canvas = self._image.canvas
+        img_bgr = cv2.resize(self._otexture, (2 * w, 2 * h))
         img_rgb = cv2.cvtColor(img_bgr, cv2.COLOR_BGR2RGB)
         img_hls = cv2.cvtColor(img_bgr, cv2.COLOR_BGR2HLS)
 

src/batgrl/gadgets/braille_image.py

@@ -203,13 +203,18 @@ def alpha(self, alpha: float):
         self._image.alpha = alpha
 
     @property
-    def path(self):
+    def path(self) -> Path | None:
         """Path to image."""
         return self._path
 
     @path.setter
-    def path(self, value):
-        self._path = value
+    def path(self, path: Path | None):
+        self._path: Path | None = path
+
+        if path is None:
+            self._otexture = np.zeros((1, 1, 3), dtype=np.uint8)
+        else:
+            self._otexture = cv2.imread(str(path.absolute()), cv2.IMREAD_COLOR)
         self._load_texture()
 
     def on_size(self):
@@ -219,11 +224,11 @@ def on_size(self):
 
     def _load_texture(self):
         h, w = self.size
-        canvas = self._image.canvas
-
-        img = cv2.imread(str(self.path.absolute()), cv2.IMREAD_COLOR)
-        img_bgr = cv2.resize(img, (2 * w, 4 * h))
+        if h == 0 or w == 0:
+            return
 
+        canvas = self._image.canvas
+        img_bgr = cv2.resize(self._otexture, (2 * w, 4 * h))
         img_rgb = cv2.cvtColor(img_bgr, cv2.COLOR_BGR2RGB)
         img_hls = cv2.cvtColor(img_bgr, cv2.COLOR_BGR2HLS)
 

src/batgrl/gadgets/braille_video.py

@@ -54,8 +54,7 @@ class BrailleVideo(Gadget):
     gray_threshold : int, default: 127
         Pixel values over this threshold in the source video will be rendered.
     enable_shading : bool, default: False
-        If true, foreground will be set to `default_fg_color` multiplied by the
-        normalized grays from the source.
+        Whether foreground colors are shaded.
     invert_colors : bool, default: False
         Invert the colors in the source before rendering.
     alpha : float, default: 1.0
@@ -90,8 +89,7 @@ class BrailleVideo(Gadget):
     gray_threshold : int
         Pixel values over this threshold in the source video will be rendered.
     enable_shading : bool
-        If true, foreground will be set to `default_fg_color` multiplied by the
-        normalized grays from the source.
+        Whether foreground colors are shaded.
     invert_colors : bool
         If true, colors in the source are inverted before video is rendered.
     alpha : float
@@ -315,13 +313,13 @@ def _release_resource(self):
             atexit.unregister(self._resource.release)
             self._resource = None
             self._current_frame = None
-            self._video.canvas["char"] = " "
+            self._video.clear()
 
     def _paint_frame(self):
-        if self._current_frame is None:
+        h, w = self.size
+        if self._current_frame is None or h == 0 or w == 0:
             return
 
-        h, w = self.size
         canvas = self._video.canvas
         upscaled = cv2.resize(self._current_frame, (2 * w, 4 * h)) > self.gray_threshold
         sectioned = np.swapaxes(upscaled.reshape(h, 4, w, 2), 1, 2)
@@ -332,7 +330,7 @@ def _paint_frame(self):
             shades = lerp(self.bg_color, self.fg_color, normals[..., None])
             canvas["fg_color"] = shades.astype(np.uint8)
         else:
-            canvas["fg_color"] = self.default_fg_color
+            canvas["fg_color"] = self.fg_color
 
     def _time_delta(self) -> float:
         return time.monotonic() - self._resource.get(cv2.CAP_PROP_POS_MSEC) / 1000
@@ -366,6 +364,7 @@ async def _play_video(self):
             self.play()
         else:
             self._current_frame = None
+            self._video.clear()
 
     def on_size(self):
         """Resize canvas and colors arrays."""
@@ -412,4 +411,4 @@ def stop(self):
         self.pause()
         self.seek(0)
         self._current_frame = None
-        self.clear()
+        self._video.clear()

src/batgrl/gadgets/console.py

@@ -237,12 +237,7 @@ def _enter_callback(textbox: Textbox):
 
 class _Prompt(Text):
     def set_text(self, text: str, **kwargs):
-        # To fake a 0-width prompt move the prompt offscreen when text is empty.
         self._text = text
-        if len(text) == 0:
-            self.left = -1
-        else:
-            self.left = 0
         super().set_text(text, **kwargs)
 
 
@@ -495,8 +490,7 @@ def update_bars():
 
     def _add_text_to_output(self, text: str, with_prompt: bool = False):
         if with_prompt:
-            prompt = self._prompt._text
-            text = f"{prompt}{text}"
+            text = f"{self._prompt._text}{text}"
         else:
             text = text.rstrip("\n")
             if not text:

src/batgrl/gadgets/gadget.py

@@ -552,7 +552,7 @@ def __init__(
         self.children: list[Gadget] = []
 
         h, w = size
-        self._size = Size(clamp(h, 1, None), clamp(w, 1, None))
+        self._size = Size(clamp(h, 0, None), clamp(w, 0, None))
         self._pos = Point(*pos)
 
         if size_hint is None:
@@ -594,7 +594,7 @@ def size(self, size: Size):
             return
 
         h, w = size
-        size = Size(clamp(int(h), 1, None), clamp(int(w), 1, None))
+        size = Size(clamp(int(h), 0, None), clamp(int(w), 0, None))
 
         if self.root:
             self.root._render_lock.acquire()

src/batgrl/gadgets/graphics.py

@@ -22,7 +22,7 @@
     clamp,
     lerp,
 )
-from .texture_tools import Interpolation, _composite
+from .texture_tools import Interpolation, _composite, resize_texture
 
 __all__ = [
     "Anchor",
@@ -214,11 +214,7 @@ def __init__(
         self.alpha = alpha
 
         h, w = self.size
-        self.texture = np.full(
-            (2 * h, w, 4),
-            default_color,
-            dtype=np.uint8,
-        )
+        self.texture = np.full((2 * h, w, 4), default_color, dtype=np.uint8)
 
     @property
     def alpha(self) -> float:
@@ -232,13 +228,8 @@ def alpha(self, alpha: float):
 
     def on_size(self):
         """Resize texture array."""
-        h, w = self._size
-
-        self.texture = cv2.resize(
-            self.texture,
-            (w, 2 * h),
-            interpolation=Interpolation._to_cv_enum[self.interpolation],
-        )
+        h, w = self.size
+        self.texture = resize_texture(self.texture, (2 * h, w), self.interpolation)
 
     @property
     def interpolation(self) -> Interpolation:

src/batgrl/gadgets/image.py

@@ -1,7 +1,6 @@
 """An image gadget."""
 from pathlib import Path
 
-import cv2
 import numpy as np
 from numpy.typing import NDArray
 
@@ -16,7 +15,7 @@
     SizeHint,
     SizeHintDict,
 )
-from .texture_tools import read_texture
+from .texture_tools import read_texture, resize_texture
 
 __all__ = [
     "Image",
@@ -214,23 +213,18 @@ def path(self) -> Path | None:
         return self._path
 
     @path.setter
-    def path(self, new_path: Path | None):
-        self._path = new_path
-        if new_path is not None:
-            self._otexture = read_texture(new_path)
+    def path(self, path: Path | None):
+        self._path = path
+        if path is None:
+            self._otexture = np.full((1, 1, 4), self.default_color, dtype=np.uint8)
         else:
-            self._otexture = np.full((2, 1, 4), self.default_color, dtype=np.uint8)
-
+            self._otexture = read_texture(path)
         self.on_size()
 
     def on_size(self):
         """Resize texture array."""
         h, w = self._size
-        self.texture = cv2.resize(
-            self._otexture,
-            (w, 2 * h),
-            interpolation=Interpolation._to_cv_enum[self.interpolation],
-        )
+        self.texture = resize_texture(self._otexture, (2 * h, w), self.interpolation)
 
     @classmethod
     def from_texture(

src/batgrl/gadgets/line_plot.py

@@ -479,10 +479,10 @@ def y_label(self, y_label: str | None):
         self._build_plot()
 
     def _build_plot(self):
-        if self.root is None:
+        h, w = self.size
+        if self.root is None or h == 0 or w == 0:
             return
 
-        h, w = self.size
         has_x_label = self._x_label_gadget.is_enabled = bool(self.x_label is not None)
         has_y_label = self._y_label_gadget.is_enabled = bool(self.y_label is not None)
 

src/batgrl/gadgets/raycaster.py

@@ -625,6 +625,10 @@ def cast_sprites(self):
 
     def _render(self, canvas_view: NDArray[Cell]):
         """Render visible region of gadget."""
+        h, w = self.size
+        if h == 0 or w == 0:
+            return
+
         # Early calculations on rays can be vectorized:
         np.dot(self._ray_angles, self.camera._plane, out=self._rotated_angles)
         with np.errstate(divide="ignore"):
@@ -637,7 +641,6 @@ def _render(self, canvas_view: NDArray[Cell]):
         np.multiply(self._sides, self._steps, out=self._sides)
         np.multiply(self._sides, self._deltas, out=self._sides)
 
-        h = self.texture.shape[0] // 2
         self.texture[:h, :, :3] = self.ceiling_color
         self.texture[h:, :, :3] = self.floor_color
         self.texture[..., 3] = 255

src/batgrl/gadgets/scroll_view.py

@@ -721,8 +721,6 @@ def scroll_to_rect(self, pos: Point, size: Size = Size(1, 1)):
 
         y, x = pos
         h, w = size
-        h = clamp(h, 1, None)
-        w = clamp(w, 1, None)
         gy, gx = self.view.pos
         ay, ax = gy + y, gx + x
         if ay < 0:

src/batgrl/gadgets/shadow_caster.py

@@ -402,6 +402,8 @@ def __init__(
     def cast_shadows(self):
         """Update texture by shadow casting all light sources."""
         h, w, _ = self.texture.shape
+        if h == 0 or w == 0:
+            return
 
         cy, cx = self.camera.pos
         ch, cw = self.camera.size

src/batgrl/gadgets/split_layout.py

@@ -271,7 +271,7 @@ def min_split_height(self) -> int:
     @min_split_height.setter
     def min_split_height(self, min_split_height: int):
         self._min_split_height = clamp(min_split_height, 1, None)
-        self.split_row = self.split_row  # Clamp split and call `on_size`
+        self.split_row = self.split_row
 
     @property
     def split_row(self) -> int:

src/batgrl/gadgets/texture_tools.py

@@ -61,7 +61,7 @@ def resize_texture(
     Parameters
     ----------
     texture : NDArray[np.uint8]
-        The texture to resize.
+        An RGBA texture to resize.
     size : Size
         The new size of the texture.
     interpolation : Interpolation, default: "linear"
@@ -72,7 +72,10 @@ def resize_texture(
     NDArray[np.uint8]
         A new uint8 RGBA array.
     """
+    old_h, old_w, _ = texture.shape
     h, w = size
+    if old_h == 0 or old_w == 0 or h == 0 or w == 0:
+        return np.zeros((h, w, 4), np.uint8)
     return cv2.resize(
         texture,
         (w, h),

src/batgrl/gadgets/video.py

@@ -275,12 +275,14 @@ def _time_delta(self) -> float:
 
     def _display_current_frame(self):
         h, w = self.size
-        if self._current_frame is not None:
-            self.texture = cv2.resize(
-                self._current_frame,
-                (w, 2 * h),
-                interpolation=Interpolation._to_cv_enum[self.interpolation],
-            )
+        if self._current_frame is None or h == 0 or w == 0:
+            return
+
+        self.texture = cv2.resize(
+            self._current_frame,
+            (w, 2 * h),
+            interpolation=Interpolation._to_cv_enum[self.interpolation],
+        )
 
     async def _play_video(self):
         if self._resource is None: