From b0a574c38708ecb837db59fe378c64b66c759557 Mon Sep 17 00:00:00 2001
From: gizak <gizak@icloud.com>
Date: Thu, 9 Apr 2015 16:40:49 -0400
Subject: [PATCH] Fix https://github.com/gizak/termui/issues/18

Add Block.chopOverflow and apply it to all widgets
---
 bar.go       |  2 +-
 block.go     | 18 ++++++++++++++++++
 chart.go     |  2 +-
 gauge.go     |  2 +-
 list.go      |  2 +-
 p.go         |  2 +-
 sparkline.go |  2 +-
 7 files changed, 24 insertions(+), 6 deletions(-)

diff --git a/bar.go b/bar.go
index 025ce26..807b02d 100644
--- a/bar.go
+++ b/bar.go
@@ -120,5 +120,5 @@ func (bc *BarChart) Buffer() []Point {
 		}
 	}
 
-	return ps
+	return bc.Block.chopOverflow(ps)
 }
diff --git a/block.go b/block.go
index 7037166..9531365 100644
--- a/block.go
+++ b/block.go
@@ -122,3 +122,21 @@ func (d *Block) SetY(y int) {
 func (d *Block) SetWidth(w int) {
 	d.Width = w
 }
+
+// chop the overflow parts
+func (d *Block) chopOverflow(ps []Point) []Point {
+	nps := make([]Point, 0, len(ps))
+	x := d.X
+	y := d.Y
+	w := d.Width
+	h := d.Height
+	for _, v := range ps {
+		if v.X >= x &&
+			v.X < x+w &&
+			v.Y >= y &&
+			v.Y < y+h {
+			nps = append(nps, v)
+		}
+	}
+	return nps
+}
diff --git a/chart.go b/chart.go
index d752362..d2cd635 100644
--- a/chart.go
+++ b/chart.go
@@ -327,5 +327,5 @@ func (lc *LineChart) Buffer() []Point {
 		ps = append(ps, lc.renderBraille()...)
 	}
 
-	return ps
+	return lc.Block.chopOverflow(ps)
 }
diff --git a/gauge.go b/gauge.go
index e437899..3e0003d 100644
--- a/gauge.go
+++ b/gauge.go
@@ -79,5 +79,5 @@ func (g *Gauge) Buffer() []Point {
 		}
 		ps = append(ps, p)
 	}
-	return ps
+	return g.Block.chopOverflow(ps)
 }
diff --git a/list.go b/list.go
index d670aa6..0640932 100644
--- a/list.go
+++ b/list.go
@@ -100,5 +100,5 @@ func (l *List) Buffer() []Point {
 			}
 		}
 	}
-	return ps
+	return l.Block.chopOverflow(ps)
 }
diff --git a/p.go b/p.go
index 22332ed..e327d74 100644
--- a/p.go
+++ b/p.go
@@ -67,5 +67,5 @@ func (p *Par) Buffer() []Point {
 		k++
 		j += w
 	}
-	return ps
+	return p.Block.chopOverflow(ps)
 }
diff --git a/sparkline.go b/sparkline.go
index 2a8cc7b..e0725d5 100644
--- a/sparkline.go
+++ b/sparkline.go
@@ -152,5 +152,5 @@ func (sl *Sparklines) Buffer() []Point {
 		oftY += l.displayHeight
 	}
 
-	return ps
+	return sl.Block.chopOverflow(ps)
 }