Solaraviz api (#2263)

* add new solara viz API

---------

Co-authored-by: pre-commit-ci[bot] <66853113+pre-commit-ci[bot]@users.noreply.github.com>
Co-authored-by: Ewout ter Hoeven <[email protected]>

mesa/visualization/UserParam.py

@@ -0,0 +1,56 @@
+class UserParam:
+    _ERROR_MESSAGE = "Missing or malformed inputs for '{}' Option '{}'"
+
+    def maybe_raise_error(self, param_type, valid):
+        if valid:
+            return
+        msg = self._ERROR_MESSAGE.format(param_type, self.label)
+        raise ValueError(msg)
+
+
+class Slider(UserParam):
+    """
+    A number-based slider input with settable increment.
+
+    Example:
+
+    slider_option = Slider("My Slider", value=123, min=10, max=200, step=0.1)
+
+    Args:
+        label: The displayed label in the UI
+        value: The initial value of the slider
+        min: The minimum possible value of the slider
+        max: The maximum possible value of the slider
+        step: The step between min and max for a range of possible values
+        dtype: either int or float
+    """
+
+    def __init__(
+        self,
+        label="",
+        value=None,
+        min=None,
+        max=None,
+        step=1,
+        dtype=None,
+    ):
+        self.label = label
+        self.value = value
+        self.min = min
+        self.max = max
+        self.step = step
+
+        # Validate option type to make sure values are supplied properly
+        valid = not (self.value is None or self.min is None or self.max is None)
+        self.maybe_raise_error("slider", valid)
+
+        if dtype is None:
+            self.is_float_slider = self._check_values_are_float(value, min, max, step)
+        else:
+            self.is_float_slider = dtype is float
+
+    def _check_values_are_float(self, value, min, max, step):
+        return any(isinstance(n, float) for n in (value, min, max, step))
+
+    def get(self, attr):
+        return getattr(self, attr)

mesa/visualization/__init__.py

@@ -0,0 +1,14 @@
+from .components.altair import make_space_altair
+from .components.matplotlib import make_plot_measure, make_space_matplotlib
+from .solara_viz import JupyterViz, SolaraViz, make_text
+from .UserParam import Slider
+
+__all__ = [
+    "JupyterViz",
+    "SolaraViz",
+    "make_text",
+    "Slider",
+    "make_space_altair",
+    "make_space_matplotlib",
+    "make_plot_measure",
+]

mesa/visualization/components/altair.py

@@ -0,0 +1,86 @@
+import contextlib
+
+import solara
+
+with contextlib.suppress(ImportError):
+    import altair as alt
+
+from mesa.visualization.utils import update_counter
+
+
+def make_space_altair(agent_portrayal=None):
+    if agent_portrayal is None:
+
+        def agent_portrayal(a):
+            return {"id": a.unique_id}
+
+    def MakeSpaceAltair(model):
+        return SpaceAltair(model, agent_portrayal)
+
+    return MakeSpaceAltair
+
+
+@solara.component
+def SpaceAltair(model, agent_portrayal, dependencies: list[any] | None = None):
+    update_counter.get()
+    space = getattr(model, "grid", None)
+    if space is None:
+        # Sometimes the space is defined as model.space instead of model.grid
+        space = model.space
+    chart = _draw_grid(space, agent_portrayal)
+    solara.FigureAltair(chart)
+
+
+def _draw_grid(space, agent_portrayal):
+    def portray(g):
+        all_agent_data = []
+        for content, (x, y) in g.coord_iter():
+            if not content:
+                continue
+            if not hasattr(content, "__iter__"):
+                # Is a single grid
+                content = [content]  # noqa: PLW2901
+            for agent in content:
+                # use all data from agent portrayal, and add x,y coordinates
+                agent_data = agent_portrayal(agent)
+                agent_data["x"] = x
+                agent_data["y"] = y
+                all_agent_data.append(agent_data)
+        return all_agent_data
+
+    all_agent_data = portray(space)
+    invalid_tooltips = ["color", "size", "x", "y"]
+
+    encoding_dict = {
+        # no x-axis label
+        "x": alt.X("x", axis=None, type="ordinal"),
+        # no y-axis label
+        "y": alt.Y("y", axis=None, type="ordinal"),
+        "tooltip": [
+            alt.Tooltip(key, type=alt.utils.infer_vegalite_type([value]))
+            for key, value in all_agent_data[0].items()
+            if key not in invalid_tooltips
+        ],
+    }
+    has_color = "color" in all_agent_data[0]
+    if has_color:
+        encoding_dict["color"] = alt.Color("color", type="nominal")
+    has_size = "size" in all_agent_data[0]
+    if has_size:
+        encoding_dict["size"] = alt.Size("size", type="quantitative")
+
+    chart = (
+        alt.Chart(
+            alt.Data(values=all_agent_data), encoding=alt.Encoding(**encoding_dict)
+        )
+        .mark_point(filled=True)
+        .properties(width=280, height=280)
+        # .configure_view(strokeOpacity=0)  # hide grid/chart lines
+    )
+    # This is the default value for the marker size, which auto-scales
+    # according to the grid area.
+    if not has_size:
+        length = min(space.width, space.height)
+        chart = chart.mark_point(size=30000 / length**2, filled=True)
+
+    return chart