Colors¶
Import Color and colors from openbacktesting. Colors are immutable RGBA values used by plotting and color inputs.
from openbacktesting import Color, colors
up = colors.GREEN
faded = up.with_transparency(80)
custom = Color.rgb(30, 120, 220, transparency=25)
parsed = Color.from_hex("#2277AA")
print(custom.to_hex())
middle = Color.from_gradient(
50, lower=0, upper=100, lower_color=colors.RED, upper_color=colors.GREEN,
)
print(middle.to_hex())
rgb takes integer red/green/blue components in 0..255. Transparency is 0..100: zero is opaque, 100 is invisible. from_hex accepts only #RRGGBB or #RRGGBBAA; the alpha byte uses 255 for opaque. to_hex() returns uppercase #RRGGBBAA for saving or passing to another application.
from_gradient(value, lower, upper, lower_color, upper_color) is called with keyword bounds/colors as shown above. It interpolates RGBA components and clamps values outside the bounds. Bounds must be finite and strictly increasing; endpoint colors must be Color values. Convert NumPy/indicator scalars with float(...) after checking validity.
Use self.plotting.line(self.average, color=faded) for a static color, or compute a scalar gradient in next() and pass it to self.plotting.bar_color(...). Color arrays are not accepted. For a user setting, declare inputs.color(colors.TEAL, title="Line color"); the runtime value is a Color.
Color¶
Immutable color compared by all four channels; alpha means opacity, with no implicit equality to strings.
| Attribute | Type | Meaning |
|---|---|---|
red |
int |
Red byte from 0 to 255. |
green |
int |
Green byte from 0 to 255. |
blue |
int |
Blue byte from 0 to 255. |
alpha |
int |
Opacity byte: 0 is transparent and 255 is opaque. |
Attributes¶
| Attribute | Meaning |
|---|---|
transparency |
0–100 transparency derived from quantized alpha; it may differ from the original percentage. |
Color.from_hex¶
Parse six- or eight-digit hexadecimal colors; append FF for six digits.
Color.rgb¶
Construct from integer RGB and 0–100 transparency; 0 is opaque, 100 is fully transparent.
Color.with_transparency¶
Replace alpha using 0–100 transparency and return a new value; do not modify or multiply the original color.
Color.to_hex¶
Return uppercase #RRGGBBAA; fully transparent colors retain RGB and do not become None.
Color.from_gradient¶
Linearly interpolate a scalar between unpremultiplied RGBA bytes at both endpoints; clamp outside the interval.
Named presets¶
The colors module exposes these Color constants. Use them directly or call .with_transparency(...).