"""
Demonstration of altering a plot's origin and orientation.

The origin parameter sets a plot's default origin to the specified corner
of the plot window. These positions has the following behavior:

* 'left' : index increases left to right
* 'right' : index increases right to left
* 'top' : index increases top to bottom
* 'bottom' : index increases bottom to top

The orientation parameter switches the x- and y-axes. Alternatively, you can
think of this as a transpose about the origin.
"""

# Major library imports
from scipy.misc import face

# Enthought library imports
from enable.api import Component, ComponentEditor
from traits.api import HasTraits, Instance
from traitsui.api import UItem, Group, View

# Chaco imports
from chaco.api import ArrayPlotData, GridContainer, Plot
from chaco.tools.api import PanTool, ZoomTool


class Demo(HasTraits):
    plot = Instance(Component)

    traits_view = View(
        Group(
            UItem("plot", editor=ComponentEditor(size=(1000, 500))),
            orientation="vertical",
        ),
        resizable=True,
        title="Demo of image origin and orientation",
    )

    def _plot_default(self):
        # Create a GridContainer to hold all of our plots: 2 rows, 4 columns:
        container = GridContainer(
            fill_padding=True,
            bgcolor="lightgray",
            use_backbuffer=True,
            shape=(2, 4),
        )

        arrangements = [
            ("top left", "h"),
            ("top right", "h"),
            ("top left", "v"),
            ("top right", "v"),
            ("bottom left", "h"),
            ("bottom right", "h"),
            ("bottom left", "v"),
            ("bottom right", "v"),
        ]
        orientation_name = {"h": "horizontal", "v": "vertical"}

        pd = ArrayPlotData(image=face())
        # Plot some bessel functions and add the plots to our container
        for origin, orientation in arrangements:
            plot = Plot(pd, default_origin=origin, orientation=orientation)
            plot.img_plot("image")

            # Attach some tools to the plot
            plot.tools.append(PanTool(plot))
            zoom = ZoomTool(plot, tool_mode="box", always_on=False)
            plot.overlays.append(zoom)

            title = "{0}, {1}"
            plot.title = title.format(
                orientation_name[orientation], origin.replace(" ", "-")
            )

            # Add to the grid container
            container.add(plot)

        return container


demo = Demo()


if __name__ == "__main__":
    demo.configure_traits()