Added graph zooming; closes #3

6 files changed, 50 insertions, 11 deletions

diff --git a/README.md b/README.md
index eb49ff2..5d8e4eb 100644
--- a/README.md
+++ b/README.md
@@ -37,7 +37,7 @@ go get github.com/cjbassi/gotop
 ### Keybinds
 
 * Quit: `q` or `<C-c>`
-* Navigation:
+* Process Navigation:
     * `<up>`/`<down>` and `j`/`k`: up and down
     * `<C-d>` and `<C-u>`: up and down half a page
     * `<C-f>` and `<C-b>`: up and down a full page
@@ -48,6 +48,7 @@ go get github.com/cjbassi/gotop
     * `p`: PID
 * `<tab>`: toggle process grouping
 * `dd`: kill the selected process or process group
+* `h` and `l`: zoom in and out of CPU and Mem graphs
 * `?`: toggles keybind help menu
 
 
diff --git a/gotop.go b/gotop.go
index a5a708a..e25841a 100644
--- a/gotop.go
+++ b/gotop.go
@@ -26,11 +26,15 @@ var (
 	procLoaded = make(chan bool, 1)
 	// used to render the proc widget whenever a key is pressed for it
 	keyPressed = make(chan bool, 1)
+	// used to render cpu and mem when zoom has changed
+	zoomed = make(chan bool, 1)
 
 	colorscheme = colorschemes.Default
 
-	minimal  = false
-	interval = time.Second
+	minimal      = false
+	interval     = time.Second
+	zoom         = 7
+	zoomInterval = 3
 
 	cpu  *w.CPU
 	mem  *w.Mem
@@ -128,6 +132,21 @@ func keyBinds() {
 			helpVisible = false
 		}
 	})
+
+	ui.On("h", func(e ui.Event) {
+		zoom += zoomInterval
+		cpu.Zoom = zoom
+		mem.Zoom = zoom
+		zoomed <- true
+	})
+	ui.On("l", func(e ui.Event) {
+		if zoom > zoomInterval {
+			zoom -= zoomInterval
+			cpu.Zoom = zoom
+			mem.Zoom = zoom
+			zoomed <- true
+		}
+	})
 }
 
 func termuiColors() {
@@ -167,8 +186,8 @@ func main() {
 	// need to do this before initializing widgets so that they can inherit the colors
 	termuiColors()
 
-	cpu = w.NewCPU(interval)
-	mem = w.NewMem(interval)
+	cpu = w.NewCPU(interval, zoom)
+	mem = w.NewMem(interval, zoom)
 	proc = w.NewProc(procLoaded, keyPressed)
 	if !minimal {
 		net = w.NewNet()
@@ -227,6 +246,10 @@ func main() {
 				if !helpVisible {
 					ui.Render(proc)
 				}
+			case <-zoomed:
+				if !helpVisible {
+					ui.Render(ui.Body)
+				}
 			case <-drawTick.C:
 				if !helpVisible {
 					ui.Render(ui.Body)
diff --git a/termui/linegraph.go b/termui/linegraph.go
index 4b01691..01d8414 100644
--- a/termui/linegraph.go
+++ b/termui/linegraph.go
@@ -12,6 +12,7 @@ type LineGraph struct {
 	*Block
 	Data      map[string][]float64
 	LineColor map[string]Color
+	Zoom      int
 
 	DefaultLineColor Color
 }
@@ -22,6 +23,7 @@ func NewLineGraph() *LineGraph {
 		Block:     NewBlock(),
 		Data:      make(map[string][]float64),
 		LineColor: make(map[string]Color),
+		Zoom:      5,
 
 		DefaultLineColor: Theme.LineGraph,
 	}
@@ -61,9 +63,18 @@ func (lc *LineGraph) Buffer() *Buffer {
 		lastY, lastX := -1, -1
 		// assign colors to `colors` and lines/points to the canvas
 		for i := len(seriesData) - 1; i >= 0; i-- {
-			x := ((lc.X + 1) * 2) - 1 - (((len(seriesData) - 1) - i) * 5)
+			x := ((lc.X + 1) * 2) - 1 - (((len(seriesData) - 1) - i) * lc.Zoom)
 			y := ((lc.Y + 1) * 4) - 1 - int((float64((lc.Y)*4)-1)*(seriesData[i]/100))
-			if x < 0 { // stop rendering at the left-most wall
+			if x < 0 {
+				// render the line to the last point up to the wall
+				if x > 0-lc.Zoom {
+					for _, p := range drawille.Line(lastX, lastY, x, y) {
+						if p.X > 0 {
+							c.Set(p.X, p.Y)
+							colors[p.X/2][p.Y/4] = seriesLineColor
+						}
+					}
+				}
 				break
 			}
 			if lastY == -1 { // if this is the first point
diff --git a/widgets/cpu.go b/widgets/cpu.go
index 82c097c..6065279 100644
--- a/widgets/cpu.go
+++ b/widgets/cpu.go
@@ -14,7 +14,7 @@ type CPU struct {
 	interval time.Duration
 }
 
-func NewCPU(interval time.Duration) *CPU {
+func NewCPU(interval time.Duration, zoom int) *CPU {
 	count, _ := psCPU.Counts(false)
 	c := &CPU{
 		LineGraph: ui.NewLineGraph(),
@@ -22,6 +22,7 @@ func NewCPU(interval time.Duration) *CPU {
 		interval:  interval,
 	}
 	c.Label = "CPU Usage"
+	c.Zoom = zoom
 	for i := 0; i < c.count; i++ {
 		key := "CPU" + strconv.Itoa(i+1)
 		c.Data[key] = []float64{0}
diff --git a/widgets/help.go b/widgets/help.go
index ff5c716..faa64b9 100644
--- a/widgets/help.go
+++ b/widgets/help.go
@@ -9,7 +9,7 @@ import (
 const KEYBINDS = `
 Quit: q or <C-c>
 
-Navigation
+Process Navigation
   - <up>/<down> and j/k: up and down
   - <C-d> and <C-u>: up and down half a page
   - <C-f> and <C-b>: up and down a full page
@@ -22,6 +22,8 @@ Process Sorting
 
 <tab>: toggle process grouping
 dd: kill the selected process or process group
+
+h and l: zoom in and out of CPU and Mem graphs
 `
 
 type HelpMenu struct {
@@ -31,7 +33,7 @@ type HelpMenu struct {
 func NewHelpMenu() *HelpMenu {
 	block := ui.NewBlock()
 	block.X = 48                                   // width - 1
-	block.Y = 15                                   // height - 1
+	block.Y = 17                                   // height - 1
 	block.XOffset = (ui.Body.Width - block.X) / 2  // X coordinate
 	block.YOffset = (ui.Body.Height - block.Y) / 2 // Y coordinate
 	return &HelpMenu{block}
diff --git a/widgets/mem.go b/widgets/mem.go
index 70bf9ae..073d9e6 100644
--- a/widgets/mem.go
+++ b/widgets/mem.go
@@ -12,12 +12,13 @@ type Mem struct {
 	interval time.Duration
 }
 
-func NewMem(interval time.Duration) *Mem {
+func NewMem(interval time.Duration, zoom int) *Mem {
 	m := &Mem{
 		LineGraph: ui.NewLineGraph(),
 		interval:  interval,
 	}
 	m.Label = "Memory Usage"
+	m.Zoom = zoom
 	m.Data["Main"] = []float64{0}
 	m.Data["Swap"] = []float64{0}