From 53b989ff609bc1b3eb37ba0cc7723877a272fdc0 Mon Sep 17 00:00:00 2001
From: Cyp <cyp561@gmail.com>
Date: Thu, 12 Feb 2009 19:24:20 +0100
Subject: [PATCH] Highlight graph of selected commit.

Makes the graph of the highlighted commit visible against the selection background, no matter which color it is.

Signed-off-by: Marco Costalba <mcostalba@gmail.com>
---
 src/common.h     |  3 +++
 src/listview.cpp | 22 +++++++++++++++++-----
 2 files changed, 20 insertions(+), 5 deletions(-)

diff --git a/src/common.h b/src/common.h
index 74bbc31..f36634c 100644
--- a/src/common.h
+++ b/src/common.h
@@ -135,6 +135,9 @@ namespace QGit {
 	                                        x == BOUNDARY_R || x == BOUNDARY_L); }
 	inline bool isMerge(int x) { return (x == MERGE_FORK || x == MERGE_FORK_R ||
 	                                     x == MERGE_FORK_L || isBoundary(x)); }
+	inline bool isActive(int x) { return (x == ACTIVE || x == INITIAL || x == BRANCH ||
+	                                      isMerge(x)); }
+
 	// custom events
 	enum EventType {
 		ERROR_EV      = 65432,
diff --git a/src/listview.cpp b/src/listview.cpp
index d5c6da7..0c226f5 100644
--- a/src/listview.cpp
+++ b/src/listview.cpp
@@ -418,6 +418,14 @@ const Rev* ListViewDelegate::revLookup(int row, FileHistory** fhPtr) const {
 	return git->revLookup(lv->sha(row), fh);
 }
 
+static QColor blend(const QColor& col1, const QColor& col2, int amount = 128) {
+
+	// Returns ((256 - amount)*col1 + amount*col2) / 256;
+	return QColor(((256 - amount)*col1.red()   + amount*col2.red()  ) / 256,
+	              ((256 - amount)*col1.green() + amount*col2.green()) / 256,
+	              ((256 - amount)*col1.blue()  + amount*col2.blue() ) / 256);
+}
+
 void ListViewDelegate::paintGraphLane(QPainter* p, int type, int x1, int x2,
                                       const QColor& col, const QColor& mergeCol, const QBrush& back) const {
 
@@ -438,7 +446,7 @@ void ListViewDelegate::paintGraphLane(QPainter* p, int type, int x1, int x2,
 	#define R_CENTER m - r, h - r, d, d
 
 	static QPen myPen(Qt::black, 2); // fast path here
-	myPen.setColor(QColor((col.red()+mergeCol.red())/2, (col.green()+mergeCol.green())/2, (col.blue()+mergeCol.blue())/2));  // Should actually fade from one colour to the other...
+	myPen.setColor(blend(col, mergeCol));  // Should actually fade from one colour to the other...
 	p->setPen(myPen);
 
 	// arc
@@ -600,16 +608,19 @@ void ListViewDelegate::paintGraph(QPainter* p, const QStyleOptionViewItem& opt,
 	QBrush back = opt.palette.base();
 	const QVector<int>& lanes(r->lanes);
 	uint laneNum = lanes.count();
-	uint mergeLane = 0;
+	uint activeLane = 0;
 	for (uint i = 0; i < laneNum; i++)
-		if (isMerge(lanes[i])) {
-			mergeLane = i;
+		if (isActive(lanes[i])) {
+			activeLane = i;
 			break;
 		}
 
 	int x1 = 0, x2 = 0;
 	int maxWidth = opt.rect.width();
 	int lw = laneWidth();
+	QColor activeColor = colors[activeLane % COLORS_NUM];
+	if (opt.state & QStyle::State_Selected)
+		activeColor = blend(activeColor, opt.palette.highlightedText().color(), 208);
 	for (uint i = 0; i < laneNum && x2 < maxWidth; i++) {
 
 		x1 = x2;
@@ -619,7 +630,8 @@ void ListViewDelegate::paintGraph(QPainter* p, const QStyleOptionViewItem& opt,
 		if (ln == EMPTY)
 			continue;
 
-		paintGraphLane(p, ln, x1, x2, colors[i % COLORS_NUM], colors[mergeLane % COLORS_NUM], back);
+		QColor color = i == activeLane ? activeColor : colors[i % COLORS_NUM];
+		paintGraphLane(p, ln, x1, x2, color, activeColor, back);
 	}
 	p->restore();
 }
-- 
2.11.4.GIT