diff --git a/src/Utils.cpp b/src/Utils.cpp
index 6a5c3491..b7980fc3 100644
--- a/src/Utils.cpp
+++ b/src/Utils.cpp
@@ -382,19 +382,6 @@ utils::linkColor()
return QPalette().color(QPalette::Link).name();
}
-QString
-utils::generateHexColor(const int hash)
-{
- QString colour("#");
- for (int i = 0; i < 3; i++) {
- int value = (hash >> (i * 8)) & 0xFF;
- colour.append(("00" + QString::number(value, 16)).right(2));
- }
- // nhlog::ui()->debug("Hex Generated {} -> {}", QString::number(hash).toStdString(),
- // colour.toStdString());
- return colour.toUpper();
-}
-
int
utils::hashQString(const QString &input)
{
@@ -404,8 +391,6 @@ utils::hashQString(const QString &input)
hash = input.at(i).digitValue() + ((hash << 5) - hash);
}
- hash *= 13;
-
return hash;
}
@@ -417,59 +402,84 @@ utils::generateContrastingHexColor(const QString &input, const QString &backgrou
const qreal backgroundLum = luminance(background);
// Create a color for the input
- auto hash = hashQString(input);
- auto colorHex = generateHexColor(hash);
+ auto hash = hashQString(input);
+ // create a hue value based on the hash of the input.
+ auto userHue = qAbs(hash % 360);
+ nhlog::ui()->debug(
+ "User Hue {} : {}", input.toStdString(), QString::number(userHue).toStdString());
+ // start with moderate saturation and lightness values.
+ auto sat = 220;
+ auto lightness = 125;
// converting to a QColor makes the luminance calc easier.
- QColor inputColor = QColor(colorHex);
+ QColor inputColor = QColor::fromHsl(userHue, sat, lightness);
- // attempt to score both the luminance and the contrast.
- // contrast should have a higher precedence, but luminance
- // helps dictate how exciting the colors are.
- auto colorLum = luminance(inputColor);
- auto contrast = computeContrast(colorLum, backgroundLum);
+ // calculate the initial luminance and contrast of the
+ // generated color. It's possible that no additional
+ // work will be necessary.
+ auto lum = luminance(inputColor);
+ auto contrast = computeContrast(lum, backgroundLum);
- // If the contrast or luminance don't meet our criteria,
- // try again and again until they do. After 10 tries,
- // the best-scoring color will be chosen.
- int att = 0;
- while ((contrast < 5 || (colorLum < 0.05 || colorLum > 0.95)) && ++att < 10) {
- hash = hashQString(input) + ((hash << 2) * 13);
- auto newHex = generateHexColor(hash);
- inputColor.setNamedColor(newHex);
- auto tmpLum = luminance(inputColor);
- auto tmpContrast = computeContrast(tmpLum, backgroundLum);
+ // If the contrast doesn't meet our criteria,
+ // try again and again until they do by modifying first
+ // the lightness and then the saturation of the color.
+ while (contrast < 5) {
+ // if our lightness is at it's bounds, try changing
+ // saturation instead.
+ if (lightness == 242 || lightness == 13) {
+ qreal newSat = qBound(26.0, sat * 1.25, 242.0);
+ nhlog::ui()->info("newSat {}", QString::number(newSat).toStdString());
- // Prioritize contrast over luminance
- // If both values are better, it's a no brainer.
- if (tmpContrast > contrast && (tmpLum > 0.05 && tmpLum < 0.95)) {
- contrast = tmpContrast;
- colorHex = newHex;
- colorLum = tmpLum;
- }
- // Otherwise, if we still can get a more
- // vibrant color and have met our contrast
- // threshold, pick the more vibrant color,
- // even if contrast will drop somewhat.
- // choosing 50% luminance as ideal.
- else if ((qAbs(tmpLum - 0.50) < qAbs(colorLum - 0.50)) && tmpContrast >= 5) {
- contrast = tmpContrast;
- colorHex = newHex;
- colorLum = tmpLum;
- }
- // Otherwise, just take the better contrast.
- else if (tmpContrast > contrast) {
- contrast = tmpContrast;
- colorHex = newHex;
- colorLum = tmpLum;
+ inputColor.setHsl(userHue, qFloor(newSat), lightness);
+ auto tmpLum = luminance(inputColor);
+ auto higherContrast = computeContrast(tmpLum, backgroundLum);
+ if (higherContrast > contrast) {
+ contrast = higherContrast;
+ sat = newSat;
+ } else {
+ newSat = qBound(26.0, sat / 1.25, 242.0);
+ inputColor.setHsl(userHue, qFloor(newSat), lightness);
+ tmpLum = luminance(inputColor);
+ auto lowerContrast = computeContrast(tmpLum, backgroundLum);
+ if (lowerContrast > contrast) {
+ contrast = lowerContrast;
+ sat = newSat;
+ }
+ }
+ } else {
+ qreal newLightness = qBound(13.0, lightness * 1.25, 242.0);
+
+ inputColor.setHsl(userHue, sat, qFloor(newLightness));
+
+ auto tmpLum = luminance(inputColor);
+ auto higherContrast = computeContrast(tmpLum, backgroundLum);
+
+ // Check to make sure we have actually improved contrast
+ if (higherContrast > contrast) {
+ contrast = higherContrast;
+ lightness = newLightness;
+ // otherwise, try going the other way instead.
+ } else {
+ newLightness = qBound(13.0, lightness / 1.25, 242.0);
+ inputColor.setHsl(userHue, sat, qFloor(newLightness));
+ tmpLum = luminance(inputColor);
+ auto lowerContrast = computeContrast(tmpLum, backgroundLum);
+ if (lowerContrast > contrast) {
+ contrast = lowerContrast;
+ lightness = newLightness;
+ }
+ }
}
}
+ // get the hex value of the generated color.
+ auto colorHex = inputColor.name();
+
nhlog::ui()->debug("Hex Generated for {}: [hex: {}, contrast: {}, luminance: {}]",
input.toStdString(),
colorHex.toStdString(),
QString::number(contrast).toStdString(),
- QString::number(colorLum).toStdString());
+ QString::number(lum).toStdString());
return colorHex;
}
@@ -496,7 +506,9 @@ utils::luminance(const QColor &col)
v <= 0.03928 ? lumRgb[i] = v / 12.92 : lumRgb[i] = qPow((v + 0.055) / 1.055, 2.4);
}
- return lumRgb[0] * 0.2126 + lumRgb[1] * 0.7152 + lumRgb[2] * 0.0722;
+ auto lum = lumRgb[0] * 0.2126 + lumRgb[1] * 0.7152 + lumRgb[2] * 0.0722;
+
+ return lum;
}
void
|
