Separate method for heatmap color scaling

I separated out the color scaling and slightly simplified the expressions.

Signed-off-by: Robert C. Helling <helling@atdotde.de>
Signed-off-by: Dirk Hohndel <dirk@hohndel.org>

1 files changed, 22 insertions, 15 deletions

diff --git a/profile-widget/diveprofileitem.cpp b/profile-widget/diveprofileitem.cpp
index 62df3b7a2..0856111cf 100644
--- a/profile-widget/diveprofileitem.cpp
+++ b/profile-widget/diveprofileitem.cpp
@@ -384,6 +384,27 @@ void DivePercentageItem::modelDataChanged(const QModelIndex &topLeft, const QMod
 		texts.last()->setAlignment(Qt::AlignLeft | Qt::AlignBottom);
 }
 
+QColor DivePercentageItem::ColorScale(double value)
+{
+	QColor color;
+	double scaledValue = value / (AMB_PERCENTAGE * N2_IN_AIR) * 1000.0;
+
+	if (scaledValue < 0.8)	// grade from cyan to blue to purple
+		color.setHsvF(0.5 + 0.25 * scaledValue / 0.8, 1.0, 1.0);
+	else if (scaledValue < 1.0)	// grade from magenta to black
+		color.setHsvF(0.75, 1.0, (1.0 - scaledValue) / 0.2);
+	else if (value < 55)	// grade from black to green
+		color.setHsvF(0.333, 1.0, (value - AMB_PERCENTAGE * N2_IN_AIR / 1000.0) / (55.0 - AMB_PERCENTAGE * N2_IN_AIR / 1000.0));
+	else if (value < 100)		// grade from green to yellow to red
+		color.setHsvF(0.333 * (100.0 - value) / 45.0, 1.0, 1.0);
+	else if (value < 120)		// M value exceeded - grade from red to white
+		color.setHsvF(0.0, 1 - (value - 100.0) / 20.0, 1.0);
+	else	// white
+		color.setHsvF(0.0, 0.0, 1.0);
+	return color;
+
+}
+
 void DivePercentageItem::paint(QPainter *painter, const QStyleOptionGraphicsItem *option, QWidget *widget)
 {
 	Q_UNUSED(option);
@@ -392,7 +413,6 @@ void DivePercentageItem::paint(QPainter *painter, const QStyleOptionGraphicsItem
 	if (polygon().isEmpty())
 		return;
 	painter->save();
-	QColor color;
 	QPen mypen;
 	mypen.setCosmetic(false);
 	mypen.setWidth(5);
@@ -400,20 +420,7 @@ void DivePercentageItem::paint(QPainter *painter, const QStyleOptionGraphicsItem
 	for (int i = 0, modelDataCount = dataModel->rowCount(); i < modelDataCount; i++) {
 		if (i < poly.count()) {
 			double value = dataModel->index(i, vDataColumn).data().toDouble();
-			if (value < 0.8 * AMB_PERCENTAGE * N2_IN_AIR / 1000.0)	// grade from cyan to blue to purple
-				color.setHsvF(0.5 + 0.25 * value / (0.8 * AMB_PERCENTAGE * N2_IN_AIR / 1000.0), 1.0, 1.0);
-			else if (value < AMB_PERCENTAGE * N2_IN_AIR / 1000.0)	// grade from magenta to black
-				color.setHsvF(0.75, 1.0, (AMB_PERCENTAGE * N2_IN_AIR / 1000.0 - value) / (0.2 * AMB_PERCENTAGE * N2_IN_AIR / 1000.0));
-			else if (value < 55)	// grade from black to green
-				color.setHsvF(0.333, 1.0, (value - AMB_PERCENTAGE * N2_IN_AIR / 1000.0) / (55.0 - AMB_PERCENTAGE * N2_IN_AIR / 1000.0));
-			else if (value < 100)		// grade from green to yellow to red
-				color.setHsvF(0.333 * (100.0 - value) / 45.0, 1.0, 1.0);
-			else if (value < 120)		// M value exceeded - grade from red to white
-				color.setHsvF(0.0, 1 - (value - 100.0) / 20.0, 1.0);
-			else	// white
-				color.setHsvF(0.0, 0.0, 1.0);
-
-			mypen.setBrush(QBrush(color));
+			mypen.setBrush(QBrush(ColorScale(value)));
 			painter->setPen(mypen);
 			painter->drawPoint(poly[i]);
 		}