KColorUtils Namespace Reference
from PyKDE4.kdeui.KColorUtils import *
Detailed Description
A set of methods used to work with colors.
Functions | |
| float | contrastRatio (QColor a0, QColor a1) |
| QColor | darken (QColor a0, float amount=0.5, float chromaGain=1.0) |
| QColor | lighten (QColor a0, float amount=0.5, float chromaInverseGain=1.0) |
| float | luma (QColor a0) |
| QColor | mix (QColor c1, QColor c2, float bias=0.5) |
| QColor | overlayColors (QColor base, QColor paint, QPainter::CompositionMode comp=QPainter.CompositionMode_SourceOver) |
| QColor | shade (QColor a0, float lumaAmount, float chromaAmount=0.0) |
| QColor | tint (QColor base, QColor color, float amount=0.3) |
Function Documentation
| float contrastRatio | ( | QColor | a0, | |
| QColor | a1 | |||
| ) |
Calculate the contrast ratio between two colors, according to the W3C/WCAG2.0 algorithm, (Lmax + 0.05)/(Lmin + 0.05), where Lmax and Lmin are the luma values of the lighter color and the darker color, respectively.
A contrast ration of 5:1 (result == 5.0) is the minimum for "normal" text to be considered readable (large text can go as low as 3:1). The ratio ranges from 1:1 (result == 1.0) to 21:1 (result == 21.0).
- See also:
- KColorUtils.luma
| QColor darken | ( | QColor | a0, | |
| float | amount=0.5, | |||
| float | chromaGain=1.0 | |||
| ) |
Adjust the luma of a color by changing its distance from black.
- Parameters:
-
amount factor by which to adjust the luma component of the color chromaGain (optional) factor by which to adjust the chroma component of the color; 1.0 means no change, 0.0 minimizes chroma
- See also:
- KColorUtils.shade
| QColor lighten | ( | QColor | a0, | |
| float | amount=0.5, | |||
| float | chromaInverseGain=1.0 | |||
| ) |
Adjust the luma of a color by changing its distance from white.
- Parameters:
-
amount factor by which to adjust the luma component of the color chromaInverseGain (optional) factor by which to adjust the chroma component of the color; 1.0 means no change, 0.0 maximizes chroma
- See also:
- KColorUtils.shade
| float luma | ( | QColor | a0 | |
| ) |
Calculate the luma of a color. Luma is weighted sum of gamma-adjusted R'G'B' components of a color. The result is similar to qGray. The range is from 0.0 (black) to 1.0 (white).
KColorUtils.darken(), KColorUtils.lighten() and KColorUtils.shade() operate on the luma of a color.
- See also:
- http://en.wikipedia.org/wiki/Luma_(video)
| QColor mix | ( | QColor | c1, | |
| QColor | c2, | |||
| float | bias=0.5 | |||
| ) |
Blend two colors into a new color by linear combination.
QColor lighter = KColorUtils.mix(myColor, Qt.white)
- Parameters:
-
c1 first color. c2 second color. bias weight to be used for the mix. bias <= 0 gives c1, bias >= 1 gives c2. bias == 0.5 gives a 50% blend of c1 and c2.
| QColor overlayColors | ( | QColor | base, | |
| QColor | paint, | |||
| QPainter::CompositionMode | comp=QPainter.CompositionMode_SourceOver | |||
| ) |
Blend two colors into a new color by painting the second color over the first using the specified composition mode.
QColor white(Qt.white); white.setAlphaF(0.5); QColor lighter = KColorUtils.overlayColors(myColor, white);
- Parameters:
-
base the base color (alpha channel is ignored). paint the color to be overlayed onto the base color. comp the CompositionMode used to do the blending.
| QColor shade | ( | QColor | a0, | |
| float | lumaAmount, | |||
| float | chromaAmount=0.0 | |||
| ) |
Adjust the luma and chroma components of a color. The amount is added to the corresponding component.
- Parameters:
-
lumaAmount amount by which to adjust the luma component of the color; 0.0 results in no change, -1.0 turns anything black, 1.0 turns anything white chromaAmount (optional) amount by which to adjust the chroma component of the color; 0.0 results in no change, -1.0 minimizes chroma, 1.0 maximizes chroma
- See also:
- KColorUtils.luma
| QColor tint | ( | QColor | base, | |
| QColor | color, | |||
| float | amount=0.3 | |||
| ) |
Create a new color by tinting one color with another. This function is meant for creating additional colors withing the same class (background, foreground) from colors in a different class. Therefore when amount is low, the luma of base is mostly preserved, while the hue and chroma of color is mostly inherited.
- Parameters:
-
base color to be tinted color color with which to tint amount how strongly to tint the base; 0.0 gives base, 1.0 gives color
KDE 4.7 PyKDE API Reference