.. _example_rgb:

========================
Plot RGB images on a map
========================

To create an RGB or RGBA composite from 3 (or 4) datasets, pass the datasets as tuple:

- the datasets must have the same size as the coordinate arrays!
- the datasets must be scaled between 0 and 1

If you pass a tuple of 3 or 4 arrays, they will be used to set the
RGB (or RGBA) colors of the shapes, e.g.:

- ``m.plot_map(fc=(<R-array>, <G-array>, <B-array>))``
- ``m.plot_map(fc=(<R-array>, <G-array>, <B-array>, <A-array>))``

You can fix individual color channels by passing a list with 1 element, e.g.:

- ``m.plot_map(fc=(<R-array>, [0.12345], <B-array>, <A-array>))``

.. image:: /_static/example_images/example_RGB.png
    :width: 75%
    :align: center

.. code-block::

    from eomaps import Maps
    import numpy as np

    x, y = np.meshgrid(np.linspace(-30, 30, 100), np.linspace(-30, 0, 50))

    # values must be between 0 and 1
    r = np.random.randint(0, 100, x.shape) / 100
    g = np.random.randint(0, 100, x.shape) / 100
    b = [0.4]
    a = np.random.randint(0, 100, x.shape) / 100

    m = Maps(figsize=(10, 5))

    m.set_data(data=None, x=x, y=y)
    m.set_shape.raster()
    m.plot_map(fc=(r, g, b, a))
    ## add gridlines and ticklabels
    g = m.add_gridlines(d=10, lw=1, linestyle='--', color='k')
    g.add_labels(fontsize=10)

    m.show()