initial

2024-09-14 15:16:36 +02:00
commit d5d9badb05
6 changed files with 295 additions and 0 deletions
@@ -0,0 +1 @@
+go run . temp.png
@@ -0,0 +1,14 @@
+module github.com/roodletoof/whiteboard
+
+go 1.23.1
+
+require github.com/hajimehoshi/ebiten/v2 v2.7.9
+
+require (
+	github.com/ebitengine/gomobile v0.0.0-20240518074828-e86332849895 // indirect
+	github.com/ebitengine/hideconsole v1.0.0 // indirect
+	github.com/ebitengine/purego v0.7.0 // indirect
+	github.com/jezek/xgb v1.1.1 // indirect
+	golang.org/x/sync v0.7.0 // indirect
+	golang.org/x/sys v0.20.0 // indirect
+)
@@ -0,0 +1,16 @@
+github.com/ebitengine/gomobile v0.0.0-20240518074828-e86332849895 h1:48bCqKTuD7Z0UovDfvpCn7wZ0GUZ+yosIteNDthn3FU=
+github.com/ebitengine/gomobile v0.0.0-20240518074828-e86332849895/go.mod h1:XZdLv05c5hOZm3fM2NlJ92FyEZjnslcMcNRrhxs8+8M=
+github.com/ebitengine/hideconsole v1.0.0 h1:5J4U0kXF+pv/DhiXt5/lTz0eO5ogJ1iXb8Yj1yReDqE=
+github.com/ebitengine/hideconsole v1.0.0/go.mod h1:hTTBTvVYWKBuxPr7peweneWdkUwEuHuB3C1R/ielR1A=
+github.com/ebitengine/purego v0.7.0 h1:HPZpl61edMGCEW6XK2nsR6+7AnJ3unUxpTZBkkIXnMc=
+github.com/ebitengine/purego v0.7.0/go.mod h1:ah1In8AOtksoNK6yk5z1HTJeUkC1Ez4Wk2idgGslMwQ=
+github.com/hajimehoshi/ebiten/v2 v2.7.9 h1:DYH/usAa9dMHcGkBIIEApJsVqDekrJBxYHmsBuly8Iw=
+github.com/hajimehoshi/ebiten/v2 v2.7.9/go.mod h1:Ulbq5xDmdx47P24EJ+Mb31Zps7vQq+guieG9mghQUaA=
+github.com/jezek/xgb v1.1.1 h1:bE/r8ZZtSv7l9gk6nU0mYx51aXrvnyb44892TwSaqS4=
+github.com/jezek/xgb v1.1.1/go.mod h1:nrhwO0FX/enq75I7Y7G8iN1ubpSGZEiA3v9e9GyRFlk=
+golang.org/x/image v0.18.0 h1:jGzIakQa/ZXI1I0Fxvaa9W7yP25TqT6cHIHn+6CqvSQ=
+golang.org/x/image v0.18.0/go.mod h1:4yyo5vMFQjVjUcVk4jEQcU9MGy/rulF5WvUILseCM2E=
+golang.org/x/sync v0.7.0 h1:YsImfSBoP9QPYL0xyKJPq0gcaJdG3rInoqxTWbfQu9M=
+golang.org/x/sync v0.7.0/go.mod h1:Czt+wKu1gCyEFDUtn0jG5QVvpJ6rzVqr5aXyt9drQfk=
+golang.org/x/sys v0.20.0 h1:Od9JTbYCk261bKm4M/mw7AklTlFYIa0bIp9BgSm1S8Y=
+golang.org/x/sys v0.20.0/go.mod h1:/VUhepiaJMQUp4+oa/7Zr1D23ma6VTLIYjOOTFZPUcA=
@@ -0,0 +1,35 @@
+package main
+
+import "github.com/hajimehoshi/ebiten/v2"
+
+
+type keymap []ebiten.Key
+var resize = keymap{
+    ebiten.KeyD,
+    ebiten.KeyK,
+}
+var drawBlack = keymap{
+    ebiten.KeyF,
+    ebiten.KeyJ,
+}
+var drawWhite = keymap{
+    ebiten.KeyS,
+    ebiten.KeyL,
+}
+var undo = keymap{
+    ebiten.KeyZ,
+    ebiten.KeyU,
+}
+var redo = keymap{
+    ebiten.KeyX,
+    ebiten.KeyR,
+}
+
+func (k keymap) check(checker func(ebiten.Key) bool) bool {
+    for _, key := range k {
+        if checker(key) {
+            return true
+        }
+    }
+    return false
+}
@@ -0,0 +1,134 @@
+package main
+
+import (
+	"image/color"
+	"log"
+	"math"
+
+	"github.com/hajimehoshi/ebiten/v2"
+	"github.com/hajimehoshi/ebiten/v2/inpututil"
+	"github.com/hajimehoshi/ebiten/v2/vector"
+)
+
+const width = 512
+const height = 512
+
+type appOption func(a *app)
+
+type app struct {
+    strokes []stroke
+    width float32
+    canvas *ebiten.Image
+    sizeAnchorPos Vec2
+    historyIndex uintptr
+}
+
+func (a *app) Draw(screen *ebiten.Image) {
+    screen.Fill(color.White)
+
+    opts := ebiten.DrawImageOptions{}
+    screen.DrawImage(a.canvas, &opts)
+
+    cursor := cursorPosition()
+    vector.StrokeCircle(
+        screen,
+        cursor.x,
+        cursor.y,
+        a.width/2,
+        3,
+        color.White,
+        true,
+    )
+    vector.StrokeCircle(
+        screen,
+        cursor.x,
+        cursor.y,
+        a.width/2,
+        1,
+        color.Black,
+        true,
+    )
+}
+
+func (a *app) Layout(_, _ int) (screenWidth int, screenHeight int) {
+    return width, height
+}
+
+func (a *app) Update() error {
+
+    check_any_drawing_input := func(checker func(ebiten.Key) bool) bool {
+        return drawWhite.check(checker) || drawBlack.check(checker)
+    }
+
+    is_drawing := check_any_drawing_input(ebiten.IsKeyPressed)
+    just_started_drawing := check_any_drawing_input(inpututil.IsKeyJustPressed)
+
+    var clr color.Color
+    if drawBlack.check(ebiten.IsKeyPressed) {
+        clr = color.Black
+    } else if drawWhite.check(ebiten.IsKeyPressed) {
+        clr = color.White
+    }
+
+    if just_started_drawing {
+        if clr == nil {
+            log.Fatal("drawing color in update is nil") // should never happen
+        }
+        a.strokes = append(a.strokes, stroke{
+        	points: []Vec2{},
+        	width:  a.width,
+        	color:  clr,
+        })
+    }
+    // TODO current history pointer is not updated as it should
+    // TODO tests
+
+    if len(a.strokes) > 0 {
+        currentStroke := &a.strokes[len(a.strokes)-1]
+        if is_drawing {
+            currentStroke.appendIfMoved(cursorPosition())
+            currentStroke.drawLast(a.canvas)
+        }
+    }
+
+    if resize.check(inpututil.IsKeyJustPressed) {
+        a.sizeAnchorPos = cursorPosition()
+    }
+
+    if resize.check(ebiten.IsKeyPressed) {
+        prevPos := a.sizeAnchorPos
+        currPos := cursorPosition()
+        reltivePos := Vec2{
+            prevPos.x - currPos.x,
+            prevPos.y - currPos.y,
+        }
+        length := float32(math.Sqrt(
+            float64(reltivePos.x) * float64(reltivePos.x) + float64(reltivePos.y) * float64(reltivePos.y),
+        ))
+        a.width = length * 2.0
+    }
+
+    return nil
+}
+
+func newApp( opts ...appOption ) app {
+    a := app{}
+    for _, opt := range opts {
+        opt(&a)
+    }
+	return a
+}
+
+func main() {
+
+    ebiten.SetWindowTitle("whiteboard")
+    ebiten.SetWindowResizingMode(ebiten.WindowResizingModeEnabled)
+    ebiten.CursorPosition()
+	whiteboardApp := newApp( func(a *app) {
+        a.width = 10
+        a.canvas = ebiten.NewImage(width, height)
+        a.canvas.Fill(color.White)
+    })
+
+	ebiten.RunGame(&whiteboardApp)
+}
@@ -0,0 +1,95 @@
+package main
+
+import (
+	"errors"
+	color_lib "image/color"
+
+	"github.com/hajimehoshi/ebiten/v2"
+	"github.com/hajimehoshi/ebiten/v2/vector"
+)
+
+type Vec2 struct {
+    x, y float32
+}
+
+func cursorPosition() Vec2 {
+    x, y := ebiten.CursorPosition()
+    return Vec2{
+        x: float32(x),
+        y: float32(y),
+    }
+}
+
+type stroke struct {
+    points []Vec2
+    width float32
+    color color_lib.Color
+}
+
+func (s *stroke) appendIfMoved(point Vec2) {
+    if len(s.points) != 0 {
+        lastPoint := s.points[len(s.points)-1]
+        if lastPoint.x == point.x && lastPoint.y == point.y {
+            return
+        }
+
+    }
+    s.points = append(s.points, point)
+}
+
+func (s *stroke) drawLast(screen *ebiten.Image) error {
+    if s.color == nil {
+        return errors.New("stroke has nil color")
+    }
+
+    if len(s.points) == 0 {
+        return nil
+    }
+
+    from := s.points[len(s.points)-1]
+    vector.DrawFilledCircle(screen, from.x, from.y, s.width/2, s.color, true)
+
+    if len(s.points) == 1 {
+        return nil
+    }
+
+    to := s.points[len(s.points)-2]
+    vector.StrokeLine(
+        screen,
+        from.x,
+        from.y,
+        to.x,
+        to.y,
+        s.width,
+        s.color,
+        true,
+    )
+    vector.DrawFilledCircle(screen, to.x, to.y, s.width/2, s.color, true)
+
+    return nil
+}
+
+func (s *stroke) draw(screen *ebiten.Image) error {
+    if s.color == nil {
+        return errors.New("stroke has nil color")
+    }
+
+    from := s.points[0]
+    vector.DrawFilledCircle(screen, from.x, from.y, s.width/2, s.color, true)
+    for _, to := range s.points[1:] {
+        vector.StrokeLine(
+            screen,
+            from.x,
+            from.y,
+            to.x,
+            to.y,
+            s.width,
+            s.color,
+            true,
+        )
+        vector.DrawFilledCircle(screen, to.x, to.y, s.width/2, s.color, true)
+        from = to
+    }
+
+    return nil
+}