erlab.interactive.colors

Functions for manipulating colors in Qt.

Functions

color_to_QColor(c[, alpha])	Convert a matplotlib color to a PySide6.QtGui.QColor.
is_dark_mode()	Check if the system is in dark mode.
pg_colormap_from_name(name[, skipCache])	Get a pyqtgraph.ColorMap from its name.
pg_colormap_names([source, exclude_local])	Get all valid pyqtgraph colormap names.
pg_colormap_powernorm(cmap, gamma[, ...])
pg_colormap_to_QPixmap(cmap[, w, h, skipCache])	Convert a pyqtgraph.ColorMap to a w-by-h QPixmap thumbnail.

Classes

BetterColorBarItem([parent, image, ...])
BetterImageItem([image])	pyqtgraph.ImageItem with improved colormap support.
ColorCycleDialog(colors, *[, parent, ...])	Dialog for selecting a color cycle.
ColorMapComboBox(*args, **kwargs)
ColorMapGammaWidget([parent, value, ...])	Slider and spinbox for adjusting colormap gamma.

class erlab.interactive.colors.BetterColorBarItem(parent=None, image=None, autoLevels=False, limits=None, pen='c', hoverPen='m', hoverBrush='#FFFFFF33', *, show_colormap_edit_menu=True, **kargs)

Bases: PlotItem

property images

property primary_image

property levels: Sequence[float]

property limits: tuple[float, float]

set_width(width)

set_dimensions(horiz_pad=None, vert_pad=None, font_size=11.0)

level_change()

level_change_fin()

spanRegion()

setSpanRegion(levels)

setLimits(limits)

addImage(image)

removeImage(image)

setImageItem(image, insert_in=None)

image_level_changed()

image_changed()

reset_levels()

setAutoLevels(value)

color_changed()

limit_changed()

mouseDragEvent(ev)

class erlab.interactive.colors.BetterImageItem(image=None, **kwargs)

Bases: ImageItem

pyqtgraph.ImageItem with improved colormap support.

Parameters:

• image (ndarray[tuple[Any, ...], dtype[TypeVar(_ScalarT, bound= generic)]] | None, default: None) – Image data

• **kwargs – Additional arguments to pyqtgraph.ImageItem.

Signals:

• sigColorChanged()

• sigLimitChanged(float, float)

set_colormap(cmap, gamma, reverse=False, high_contrast=False, zero_centered=False, update=True)

set_pg_colormap(cmap, update=True)

class erlab.interactive.colors.ColorCycleDialog(colors, *, parent=None, preview_cursors=False, opacity_values=(0.95, 0.75, 0.15, 0.35), default_colors=None)

Bases: QDialog

Dialog for selecting a color cycle.

This dialog takes a list of colors and allows the user to edit each color in the cycle, or overwrite the entire cycle by sampling from a colormap.

Parameters:

• colors (Iterable[QColor]) – An iterable of colors to use as the initial color cycle.

• parent (QWidget | None, default: None) – The parent widget for the dialog.

• preview_cursors (bool, default: False) – If True, the preview will include cursor lines and spans with the selected colors.

• opacity_values (tuple[float, float, float, float], default: (0.95, 0.75, 0.15, 0.35)) – A tuple of four float values representing the opacity for the cursor line, cursor line hover, span background, and span edge, respectively. Each value should be between 0 and 1, where 1 is fully opaque and 0 is fully transparent.

• default_colors (Iterable[QColor] | None, default: None) – An iterable of default colors to return to when the user clicks “Restore Defaults”. If None, the restore defaults button will not be shown.

property colors: tuple[QColor]

Return the current color cycle.

setup_ui()

set_from_cmap()

Set the color cycle from a colormap.

reset()

restore_defaults()

Restore the default colors if provided.

accept()

Accept the dialog and emit the new colors.

class erlab.interactive.colors.ColorMapComboBox(*args, **kwargs)

Bases: QComboBox

clear()

showEvent(event)

closeEvent(event)

load_thumbnail(index)

load_all()

showPopup()

setPopupMinimumWidthForItems()

hidePopup()

setDefaultCmap(cmap)

resetCmap()

setCurrentText(text)

Set the current text of the combobox.

class erlab.interactive.colors.ColorMapGammaWidget(parent=None, value=1.0, slider_cls=None, spin_cls=None)

Bases: QWidget

Slider and spinbox for adjusting colormap gamma.

Signals:

valueChanged(float)

value()

setValue(value)

spin_changed(value)

slider_changed(value)

gamma_scale(y)

gamma_scale_inv(x)

erlab.interactive.colors.color_to_QColor(c, alpha=None)

Convert a matplotlib color to a PySide6.QtGui.QColor.

Parameters:

• c (tuple[float, float, float] | str | tuple[float, float, float, float] | tuple[tuple[float, float, float] | str, float] | tuple[tuple[float, float, float, float], float]) – A valid matplotlib color. See the matplotlib documentation for more information.

• alpha (float | None, default: None) – If supplied, applies transparency to the color.

Returns:

PySide6.QtGui.QColor

Return type:

QColor

erlab.interactive.colors.is_dark_mode()

Check if the system is in dark mode.

If a QApplication is not running, this will always return False.

erlab.interactive.colors.pg_colormap_from_name(name, skipCache=True)

Get a pyqtgraph.ColorMap from its name.

Parameters:

• name (str) – A valid colormap name.

• skipCache (bool, default: True) – Whether to skip cache, by default True. Passed onto pyqtgraph.colormap.get().

Returns:

pyqtgraph.ColorMap

Return type:

ColorMap

erlab.interactive.colors.pg_colormap_names(source='all', exclude_local=False)

Get all valid pyqtgraph colormap names.

Parameters:

• source (Literal['local', 'all', 'matplotlib'], default: "all") –

  • “local”: only built-in/pyqtgraph colormaps

  • ”matplotlib”: only matplotlib colormaps

  • ”all”: local + colorcet + matplotlib

• exclude_local (bool, default: False) – If True, drop local colormaps from the final list.

Returns:

list of str – Ordered, de-duplicated list of colormap names.

Return type:

list[str]

erlab.interactive.colors.pg_colormap_powernorm(cmap, gamma, reverse=False, high_contrast=False, zero_centered=False, N=65536)

erlab.interactive.colors.pg_colormap_to_QPixmap(cmap, w=64, h=16, skipCache=True)

Convert a pyqtgraph.ColorMap to a w-by-h QPixmap thumbnail.

Parameters:

• cmap (str | ColorMap) – The colormap.

• w (int, default: 64) – Specifies the dimension of the pixmap.

• h (int, default: 16) – Specifies the dimension of the pixmap.

• skipCache (bool, optional) – Whether to skip cache, by default True. Passed onto pg_colormap_from_name().

Returns:

PySide6.QtGui.QPixmap

Return type:

QPixmap