Fixed zoom bug by writing some tests. Also moved thigns around a lot.

.gitignore

@@ -2,5 +2,4 @@ build/
 *.log
 *.out
 blank.png
-stdin_forward
-xzoom/xzoom_debug
+interfacer/interfacer

Dockerfile

@@ -8,10 +8,10 @@ RUN apk add --no-cache xvfb xdotool@testing ffmpeg openssh mosh firefox
 # Generate host keys
 RUN ssh-keygen -A
 
-# Installing Hiptext, video to text renderer and our own stdin_forward
+# Installing Hiptext, video to text renderer and our own interface.go
 RUN apk --no-cache add --virtual build-dependencies \
   build-base git go freetype-dev jpeg-dev ffmpeg-dev ragel libx11-dev libxt-dev
-# setup GOPATH and GOBIN and build stdin_forward
+# setup GOPATH and GOBIN and build interface.go
 RUN apk --no-cache add libgflags-dev@testing glog-dev@testing
 RUN mkdir -p build \
   && cd build \

stdin_forward.go → interfacer/interfacer.go

@@ -3,6 +3,7 @@ package main
 import (
 	"fmt"
 	"strings"
+	"path/filepath"
 	"time"
 	"os"
 	"os/exec"
@@ -17,15 +18,15 @@ import (
 // NB: The following comments are parsed by `go build` ...
 
 // #cgo LDFLAGS: -lXext -lX11 -lXt
-// #include "xzoom/xzoom.h"
+// #include "../xzoom/xzoom.h"
 import "C"
 
-var logfile = "./input.log"
+var logfile string
 var current string
 var curev termbox.Event
 var lastMouseButton string
-var desktopWidth float32 = 1600
-var desktopHeight float32 = 1200
+var desktopWidth = float32(C.WIDTH)
+var desktopHeight = float32(C.HEIGHT)
 var desktopXFloat float32
 var desktopYFloat float32
 var roundedDesktopX int
@@ -35,14 +36,20 @@ var roundedDesktopY int
 var hipWidth int
 var hipHeight int
 
+var panning bool
 var panNeedsSetup bool
 var panCachedXOffset float32
 var panCachedYOffset float32
 
 func initialise() {
-	tErr := os.Truncate(logfile, 0)
-	if tErr != nil {
-		panic(tErr)
+	dir, err := filepath.Abs(filepath.Dir(os.Args[0]))
+	if err != nil {
+		panic(err)
+	}
+	os.Mkdir(filepath.Join(dir, "..", "logs"), os.ModePerm)
+	logfile = fmt.Sprintf(filepath.Join(dir, "..", "logs", "input.log"))
+	if _, err := os.Stat(logfile); err == nil {
+		os.Truncate(logfile, 0)
 	}
 	log("Starting...")
 	calculateHipDimensions()
@@ -85,6 +92,13 @@ func log(msg string) {
 	}
 }
 
+func getXGrab() int {
+	return int(C.xgrab)
+}
+func getYGrab() int {
+	return int(C.ygrab)
+}
+
 // Issue an xdotool command to simulate mouse and keyboard input
 func xdotool(args ...string) {
 	log(strings.Join(args, " "))
@@ -133,16 +147,14 @@ func mouseButtonStr(k termbox.Key) []string {
 		return []string{"mouseup", lastMouseButton}
 	case termbox.MouseWheelUp:
 		if ctrlPressed() {
-			C.magx++
-			C.magy++
+			zoom("in")
 			return []string{"noop"}
 		}
 		return []string{"click", "4"}
 	case termbox.MouseWheelDown:
 		if ctrlPressed() {
-			if C.magx > 1 {
-				C.magx--
-				C.magy--
+			if C.magnification > 1 {
+				zoom("out")
 	    }
 			return []string{"noop"}
 		}
@@ -151,6 +163,59 @@ func mouseButtonStr(k termbox.Key) []string {
 	return []string{""}
 }
 
+func zoom(direction string) {
+	oldZoom := C.magnification
+
+	// The actual zoom
+	if direction == "in" {
+		C.magnification++
+	} else {
+		C.magnification--
+	}
+  C.width[C.SRC]  = (C.WIDTH + C.magnification - 1) / C.magnification;
+  C.height[C.SRC] = (C.HEIGHT + C.magnification - 1) / C.magnification;
+
+	// Move the viewport so that the mouse is still over the same part of
+	// the desktop.
+	factor := float32(oldZoom) / float32(C.magnification)
+	magnifiedRelativeX := factor * (desktopXFloat - float32(C.xgrab))
+	magnifiedRelativeY := factor * (desktopYFloat - float32(C.ygrab))
+	C.xgrab = C.int(desktopXFloat - magnifiedRelativeX)
+	C.ygrab = C.int(desktopYFloat - magnifiedRelativeY)
+
+	keepViewportInDesktop()
+}
+
+func keepViewportInDesktop() {
+	// Manage the viewport size
+	if C.width[C.SRC] < 1 {
+		C.width[C.SRC] = 1
+	}
+	if C.width[C.SRC] > C.WIDTH {
+		C.width[C.SRC] = C.WIDTH
+	}
+	if C.height[C.SRC] < 1 {
+		C.height[C.SRC] = 1
+	}
+	if C.height[C.SRC] > C.HEIGHT {
+		C.height[C.SRC] = C.HEIGHT
+	}
+
+	// Manage the viewport position
+	if C.xgrab > (C.WIDTH - C.width[C.SRC]) {
+		C.xgrab = C.WIDTH - C.width[C.SRC]
+	}
+	if C.xgrab < 0 {
+		C.xgrab = 0
+	}
+	if C.ygrab > (C.HEIGHT - C.height[C.SRC]) {
+		C.ygrab = C.HEIGHT - C.height[C.SRC]
+	}
+	if C.ygrab < 0 {
+		C.ygrab = 0
+	}
+}
+
 // Auxillary data. Whether the mouse was moving or a mod key like CTRL
 // is being pressed at the same time.
 func modStr(m termbox.Modifier) string {
@@ -170,27 +235,29 @@ func modStr(m termbox.Modifier) string {
 }
 
 func mouseEvent() {
+	log(
+		fmt.Sprintf(
+			"EventMouse: x: %d, y: %d, b: %s, mod: %s",
+			curev.MouseX, curev.MouseY, mouseButtonStr(curev.Key), modStr(curev.Mod)))
+
 	setCurrentDesktopCoords()
 	// Always move the mouse first so that button presses are correct. This is because we're not constantly
 	// updating the mouse position, *unless* a drag event is happening. This saves bandwidth. Also, mouse
 	// movement isn't supported on all terminals.
 	xdotool("mousemove", fmt.Sprintf("%d", roundedDesktopX), fmt.Sprintf("%d", roundedDesktopY))
 
-	log(
-		fmt.Sprintf(
-			"EventMouse: x: %d, y: %d, b: %s, mod: %s",
-			curev.MouseX, curev.MouseY, mouseButtonStr(curev.Key), modStr(curev.Mod)))
-
 	if ctrlPressed() && mouseMotion() && lastMouseButton == "1" {
-		C.pan = 1
-		if panNeedsSetup == true {
+		panning = true
+		if panNeedsSetup {
 			panCachedXOffset = float32(C.xgrab)
 			panCachedYOffset = float32(C.ygrab)
+			panNeedsSetup = false
 		}
-		panNeedsSetup = false
+		C.xgrab = C.int(desktopXFloat - panCachedXOffset)
+		C.ygrab = C.int(desktopYFloat - panCachedYOffset)
 	} else {
 		panNeedsSetup = true
-		C.pan = 0
+		panning = false
 		if !ctrlPressed() {
 			xdotool(mouseButtonStr(curev.Key)...)
 		}
@@ -207,7 +274,7 @@ func setCurrentDesktopCoords() {
 	eventY := float32(curev.MouseY)
 	width := float32(C.width[C.SRC])
 	height := float32(C.height[C.SRC])
-	if C.pan == 1 {
+	if panning {
 		// When panning starts we want to do it all within the same viewport.
 		// Without the caching here, then the viewport would change for each
 		// mouse movement and panning becomes overly sensitive.
@@ -222,7 +289,7 @@ func setCurrentDesktopCoords() {
 	log(
 		fmt.Sprintf(
 			"setCurrentDesktopCoords: tw: %d, th: %d, dx: %d, dy: %d, mag: %d",
-			hipHeightFloat, hipWidthFloat, desktopXFloat, desktopYFloat, C.magx))
+			hipHeightFloat, hipWidthFloat, eventX, width, C.magnification))
 	roundedDesktopX = roundToInt(desktopXFloat)
 	roundedDesktopY = roundToInt(desktopYFloat)
 }

interfacer/mouse_input_test.go

@@ -0,0 +1,95 @@
+package main
+
+import (
+	"github.com/nsf/termbox-go"
+	. "github.com/onsi/ginkgo"
+	. "github.com/onsi/gomega"
+	"testing"
+)
+
+func TestMouseInput(t *testing.T) {
+  RegisterFailHandler(Fail)
+  RunSpecs(t, "Mouse Input Suite")
+}
+
+var _ = Describe("Mouse Input", func() {
+	BeforeEach(func() {
+    err := termbox.Init()
+  	if err != nil {
+  		panic(err)
+  	}
+  	initialise()
+  	hipWidth = 90
+  	hipHeight = 30
+  	setCurrentDesktopCoords()
+	})
+
+  AfterEach(func(){
+  	termbox.Close()
+  })
+
+	Describe("Mouse position", func(){
+		It("Should work in the top left", func() {
+			curev.MouseX = 30
+		  curev.MouseY = 10
+			setCurrentDesktopCoords()
+			Expect(roundedDesktopX).To(Equal(533))
+    	Expect(roundedDesktopY).To(Equal(400))
+		})
+		It("Should work in the middle", func() {
+			curev.MouseX = 45
+		  curev.MouseY = 15
+			setCurrentDesktopCoords()
+			Expect(roundedDesktopX).To(Equal(800))
+    	Expect(roundedDesktopY).To(Equal(600))
+		})
+		It("Should work in the bottom right", func() {
+			curev.MouseX = 60
+		  curev.MouseY = 20
+			setCurrentDesktopCoords()
+			Expect(roundedDesktopX).To(Equal(1067))
+    	Expect(roundedDesktopY).To(Equal(800))
+		})
+	})
+
+	Describe("Zooming", func() {
+    BeforeEach(func(){
+      curev.MouseX = 30
+      curev.MouseY = 10
+      setCurrentDesktopCoords()
+    })
+		It("Should zoom in once", func() {
+			Expect(getXGrab()).To(Equal(0))
+			Expect(getYGrab()).To(Equal(0))
+    	Expect(roundedDesktopX).To(Equal(533))
+    	Expect(roundedDesktopY).To(Equal(400))
+    	zoom("in")
+    	setCurrentDesktopCoords()
+			Expect(getXGrab()).To(Equal(266))
+			Expect(getYGrab()).To(Equal(200))
+      Expect(roundedDesktopX).To(Equal(533))
+      Expect(roundedDesktopY).To(Equal(400))
+		})
+		It("Should zoom in then out", func() {
+    	zoom("in")
+    	setCurrentDesktopCoords()
+			zoom("out")
+			zoom("out")
+			setCurrentDesktopCoords()
+			Expect(getXGrab()).To(Equal(0))
+			Expect(getYGrab()).To(Equal(0))
+      Expect(roundedDesktopX).To(Equal(533))
+      Expect(roundedDesktopY).To(Equal(400))
+		})
+		It("Should zoom near an edge without breaking out", func() {
+			curev.MouseX = 0
+      curev.MouseY = 0
+      setCurrentDesktopCoords()
+    	zoom("in")
+			Expect(getXGrab()).To(Equal(0))
+			Expect(getYGrab()).To(Equal(0))
+      Expect(roundedDesktopX).To(Equal(0))
+      Expect(roundedDesktopY).To(Equal(0))
+		})
+	})
+})

run.sh

@@ -20,12 +20,12 @@ UDP_URI='udp://127.0.0.1:1234'
 # |              |                |
 # ---------------------------------
 # So xzoom mirrors the desktop and ffmpeg streams the xzoom window.
-Xvfb :0 -screen 0 "$(($DESKTOP_WIDTH * 2))"x"$DESKTOP_HEIGHT"x16 > xvfb.log 2>&1 &
+Xvfb :0 -screen 0 "$(($DESKTOP_WIDTH * 2))"x"$DESKTOP_HEIGHT"x16 > ./logs/xvfb.log 2>&1 &
 
 # TODO: detect X start rather than sleep
 sleep 1
 
-/usr/bin/firefox >> xvfb.log 2>&1 &
+/usr/bin/firefox >> ./logs/xvfb.log 2>&1 &
 
 # Convert the X framebuffer desktop into a video stream, but only stream the
 # right hand side where the xzoom window is.
@@ -37,22 +37,22 @@ ffmpeg \
   -vcodec mpeg2video \
   -f mpegts \
   $UDP_URI \
-  > ffmpeg.log 2>&1 &
+  > ./logs/ffmpeg.log 2>&1 &
 
 # The above ffmpeg can take a while to open the UDP stream, so wait a little
 # TODO: detect the stream's presence rather than sleep
 sleep 1
 
 # Intercept STDIN (mouse and keypresses) and forward to the X framebuffer via xdotool
-(./stdin_forward <&3 > interface.log 2>&1 &) 3<&0
+(./interfacer/interfacer <&3 > ./logs/interface.log 2>&1 &) 3<&0
 
 # Hiptext renders images and videos into text characters displayable in a terminal.
 # It complains unless you specify the exact path to the font, seems like a bug to me.
 # TODO: support variable width, ideally dynamic sizing
 hiptext \
   -font /usr/share/fonts/ttf-dejavu/DejaVuSansMono.ttf \
   $UDP_URI \
-  2> hiptext.log
+  2> ./logs/hiptext.log
 
 # Kill all the subprocesses created in this script if the script itself exits
 trap "trap - SIGTERM && kill -- -$$" SIGINT SIGTERM EXIT