Updated Path

* Added NewPath and NewPathFromSvg methods to Canvas interface
* Removed NewPath function
* Removed Reset methods from Path interface

CHANGELOG.md

@@ -5,6 +5,9 @@
 * Added "transform" property and Transform interface
 * Added OpenRawResource function
 * Added RemoveClientItem method to Session interface
+* Added NewPath and NewPathFromSvg methods to Canvas interface
+* Removed NewPath function
+* Removed Reset methods from Path interface
 
 # v0.16.0
 * Can use ListAdapter as "content" property value of ListLayout

README-ru.md

@@ -4443,7 +4443,17 @@ rotation - угол поворота эллипса относительно ц
 
 #### Path
 
-Интерфейс Path позволяет описать сложную фигуру. Создается Path с помощью функции NewPath().
+Интерфейс Path позволяет описать сложную фигуру. Для создания объекта Path используются два метода Canvas:
+
+	NewPath() Path
+	NewPathFromSvg(data string) Path
+
+Метод NewPath() создает пустую фигуру. Далее вы должны описать фигуру используя методы интерфейса Path
+
+Метод NewPathFromSvg(data string) Path создает фигуру описанную в параметре data. 
+Параметр data является описанием фигуры в формате елемента <path> svg изображения. Например
+
+	path := canvas.NewPathFromSvg("m 305,77.362183 c 0,0 -3,8.648649 -13,21.621616 -10,12.972981 -17,18.378381 -17,18.378381 0,0 6,4.32433 17,18.37838 11,14.05406 13,21.62162 13,21.62162 0,0 7.83867,-14.92584 13,-21.62162 10,-12.97297 17,-18.37838 17,-18.37838 0,0 -7,-5.4054 -17,-18.378381 C 308,86.010832 305,77.362183 305,77.362183 Z")
 
 После создания вы должны описать фигуру. Для этого могут использоваться следующие функции интерфейса:
 

README.md

@@ -4411,7 +4411,17 @@ rotation - the angle of rotation of the ellipse relative to the center in radian
 
 #### Path
 
-The Path interface allows you to describe a complex shape. Path is created using the NewPath () function.
+The Path interface allows you to describe a complex shape. Two Canvas methods are used to create a Path object:
+
+	NewPath() Path
+	NewPathFromSvg(data string) Path
+
+The NewPath() method creates an empty shape. Next, you must describe the shape using the methods of the Path interface
+
+The NewPathFromSvg(data string) Path method creates the shape described in the data parameter.
+The data parameter is a description of the shape in the format of a <path> svg image element. For example
+
+	path := canvas.NewPathFromSvg("m 305,77.362183 c 0,0 -3,8.648649 -13,21.621616 -10,12.972981 -17,18.378381 -17,18.378381 0,0 6,4.32433 17,18.37838 11,14.05406 13,21.62162 13,21.62162 0,0 7.83867,-14.92584 13,-21.62162 10,-12.97297 17,-18.37838 17,-18.37838 0,0 -7,-5.4054 -17,-18.378381 C 308,86.010832 305,77.362183 305,77.362183 Z")
 
 Once created, you must describe the shape. For this, the following interface functions can be used:
 

app_scripts.js

@@ -2136,3 +2136,11 @@ function setCssVar(tag, value) {
 		root.style.setProperty(tag, value);
 	}
 }
+
+function createPath2D(svg) {
+	if (svg) {
+		return new Path2D(svg);
+	} else {
+		return new Path2D();
+	}
+}

canvas.go

@@ -263,6 +263,11 @@ type Canvas interface {
 	// and is stroked (outlined) according to the current strokeStyle and other context settings
 	FillAndStrokeEllipse(x, y, radiusX, radiusY, rotation float64)
 
+	// NewPath creates a new Path object
+	NewPath() Path
+	// NewPathFromSvg creates a new Path and initialize it by a string consisting of SVG path data
+	NewPathFromSvg(data string) Path
+
 	// FillPath draws a path that is filled according to the current FillStyle.
 	FillPath(path Path)
 	// StrokePath draws a path that is stroked (outlined) according to the current strokeStyle
@@ -346,8 +351,7 @@ func (canvas *canvasData) ClipRect(x, y, width, height float64) {
 }
 
 func (canvas *canvasData) ClipPath(path Path) {
-	path.create(canvas.session)
-	canvas.session.callCanvasFunc("clip")
+	canvas.session.callCanvasFunc("clip", path.obj())
 }
 
 func (canvas *canvasData) SetScale(x, y float64) {
@@ -779,19 +783,16 @@ func (canvas *canvasData) StrokeText(x, y float64, text string) {
 }
 
 func (canvas *canvasData) FillPath(path Path) {
-	path.create(canvas.session)
-	canvas.session.callCanvasFunc("fill")
+	canvas.session.callCanvasFunc("fill", path.obj())
 }
 
 func (canvas *canvasData) StrokePath(path Path) {
-	path.create(canvas.session)
-	canvas.session.callCanvasFunc("stroke")
+	canvas.session.callCanvasFunc("stroke", path.obj())
 }
 
 func (canvas *canvasData) FillAndStrokePath(path Path) {
-	path.create(canvas.session)
-	canvas.session.callCanvasFunc("fill")
-	canvas.session.callCanvasFunc("stroke")
+	canvas.session.callCanvasFunc("fill", path.obj())
+	canvas.session.callCanvasFunc("stroke", path.obj())
 }
 
 func (canvas *canvasData) DrawLine(x0, y0, x1, y1 float64) {

data.go

@@ -134,7 +134,7 @@ func (object *dataObject) PropertyObject(tag string) DataObject {
 }
 
 func (object *dataObject) setNode(node DataNode) {
-	if object.property == nil || len(object.property) == 0 {
+	if len(object.property) == 0 {
 		object.property = []DataNode{node}
 	} else {
 		tag := node.Tag()

httpHandler.go

@@ -1,3 +1,5 @@
+//go:build !wasm
+
 package rui
 
 import (
@@ -39,6 +41,7 @@ Example for echo:
 		}
 	})
 */
+
 func NewHandler(urlPrefix string, createContentFunc func(Session) SessionContent, params AppParams) *httpHandler {
 	app := new(application)
 	app.params = params

path.go

@@ -2,9 +2,6 @@ package rui
 
 // Path is a path interface
 type Path interface {
-	// Reset erases the Path
-	Reset()
-
 	// MoveTo begins a new sub-path at the point specified by the given (x, y) coordinates
 	MoveTo(x, y float64)
 
@@ -58,79 +55,76 @@ type Path interface {
 	// If the shape has already been closed or has only one point, this function does nothing.
 	Close()
 
-	create(session Session)
-}
-
-type pathElement struct {
-	funcName string
-	args     []any
+	//create(session Session)
+	obj() any
 }
 
 type pathData struct {
-	elements []pathElement
+	session Session
+	varName any
 }
 
 // NewPath creates a new empty Path
-func NewPath() Path {
+func (canvas *canvasData) NewPath() Path {
 	path := new(pathData)
-	path.Reset()
+	path.session = canvas.session
+	path.varName = canvas.session.createPath("")
 	return path
 }
 
-func (path *pathData) Reset() {
-	path.elements = []pathElement{
-		{funcName: "beginPath", args: []any{}},
-	}
+func (canvas *canvasData) NewPathFromSvg(data string) Path {
+	path := new(pathData)
+	path.session = canvas.session
+	path.varName = canvas.session.createPath(data)
+	return path
 }
 
 func (path *pathData) MoveTo(x, y float64) {
-	path.elements = append(path.elements, pathElement{funcName: "moveTo", args: []any{x, y}})
+	path.session.callCanvasVarFunc(path.varName, "moveTo", x, y)
 }
 
 func (path *pathData) LineTo(x, y float64) {
-	path.elements = append(path.elements, pathElement{funcName: "lineTo", args: []any{x, y}})
+	path.session.callCanvasVarFunc(path.varName, "lineTo", x, y)
 }
 
 func (path *pathData) ArcTo(x0, y0, x1, y1, radius float64) {
 	if radius > 0 {
-		path.elements = append(path.elements, pathElement{funcName: "arcTo", args: []any{x0, y0, x1, y1, radius}})
+		path.session.callCanvasVarFunc(path.varName, "arcTo", x0, y0, x1, y1, radius)
 	}
 }
 
 func (path *pathData) Arc(x, y, radius, startAngle, endAngle float64, clockwise bool) {
 	if radius > 0 {
 		if !clockwise {
-			path.elements = append(path.elements, pathElement{funcName: "arc", args: []any{x, y, radius, startAngle, endAngle, true}})
+			path.session.callCanvasVarFunc(path.varName, "arc", x, y, radius, startAngle, endAngle, true)
 		} else {
-			path.elements = append(path.elements, pathElement{funcName: "arc", args: []any{x, y, radius, startAngle, endAngle}})
+			path.session.callCanvasVarFunc(path.varName, "arc", x, y, radius, startAngle, endAngle)
 		}
 	}
 }
 
 func (path *pathData) BezierCurveTo(cp0x, cp0y, cp1x, cp1y, x, y float64) {
-	path.elements = append(path.elements, pathElement{funcName: "bezierCurveTo", args: []any{cp0x, cp0y, cp1x, cp1y, x, y}})
+	path.session.callCanvasVarFunc(path.varName, "bezierCurveTo", cp0x, cp0y, cp1x, cp1y, x, y)
 }
 
 func (path *pathData) QuadraticCurveTo(cpx, cpy, x, y float64) {
-	path.elements = append(path.elements, pathElement{funcName: "quadraticCurveTo", args: []any{cpx, cpy, x, y}})
+	path.session.callCanvasVarFunc(path.varName, "quadraticCurveTo", cpx, cpy, x, y)
 }
 
 func (path *pathData) Ellipse(x, y, radiusX, radiusY, rotation, startAngle, endAngle float64, clockwise bool) {
 	if radiusX > 0 && radiusY > 0 {
 		if !clockwise {
-			path.elements = append(path.elements, pathElement{funcName: "ellipse", args: []any{x, y, radiusX, radiusY, rotation, startAngle, endAngle, true}})
+			path.session.callCanvasVarFunc(path.varName, "ellipse", x, y, radiusX, radiusY, rotation, startAngle, endAngle, true)
 		} else {
-			path.elements = append(path.elements, pathElement{funcName: "ellipse", args: []any{x, y, radiusX, radiusY, rotation, startAngle, endAngle}})
+			path.session.callCanvasVarFunc(path.varName, "ellipse", x, y, radiusX, radiusY, rotation, startAngle, endAngle)
 		}
 	}
 }
 
 func (path *pathData) Close() {
-	path.elements = append(path.elements, pathElement{funcName: "close", args: []any{}})
+	path.session.callCanvasVarFunc(path.varName, "close")
 }
 
-func (path *pathData) create(session Session) {
-	for _, element := range path.elements {
-		session.callCanvasFunc(element.funcName, element.args...)
-	}
+func (path *pathData) obj() any {
+	return path.varName
 }

popup.go

@@ -683,7 +683,7 @@ func (manager *popupManager) showPopup(popup Popup) {
 	}
 
 	session := popup.Session()
-	if manager.popups == nil || len(manager.popups) == 0 {
+	if len(manager.popups) == 0 {
 		manager.popups = []Popup{popup}
 	} else {
 		manager.popups = append(manager.popups, popup)

session.go

@@ -24,6 +24,7 @@ type bridge interface {
 	callCanvasVarFunc(v any, funcName string, args ...any)
 	callCanvasImageFunc(url string, property string, funcName string, args ...any)
 	createCanvasVar(funcName string, args ...any) any
+	createPath2D(arg string) any
 	updateCanvasProperty(property string, value any)
 	canvasFinish()
 	canvasTextMetrics(htmlID, font, text string) TextMetrics
@@ -151,6 +152,7 @@ type Session interface {
 	canvasStart(htmlID string) bool
 	callCanvasFunc(funcName string, args ...any)
 	createCanvasVar(funcName string, args ...any) any
+	createPath(arg string) any
 	callCanvasVarFunc(v any, funcName string, args ...any)
 	callCanvasImageFunc(url string, property string, funcName string, args ...any)
 	updateCanvasProperty(property string, value any)
@@ -561,6 +563,13 @@ func (session *sessionData) createCanvasVar(funcName string, args ...any) any {
 	return nil
 }
 
+func (session *sessionData) createPath(arg string) any {
+	if session.bridge != nil {
+		return session.bridge.createPath2D(arg)
+	}
+	return nil
+}
+
 func (session *sessionData) callCanvasVarFunc(v any, funcName string, args ...any) {
 	if session.bridge != nil && v != nil {
 		session.bridge.callCanvasVarFunc(v, funcName, args...)

sessionTheme.go

@@ -313,7 +313,7 @@ func (session *sessionData) Language() string {
 		return session.language
 	}
 
-	if session.languages != nil && len(session.languages) > 0 {
+	if len(session.languages) > 0 {
 		return session.languages[0]
 	}
 

viewClip.go

@@ -454,11 +454,7 @@ func (clip *polygonClip) cssStyle(session Session) string {
 }
 
 func (clip *polygonClip) valid(session Session) bool {
-	if clip.points == nil || len(clip.points) == 0 {
-		return false
-	}
-
-	return true
+	return len(clip.points) > 0
 }
 
 func parseClipShape(obj DataObject) ClipShape {

viewsContainer.go

@@ -66,7 +66,7 @@ func (container *viewsContainerData) Append(view View) {
 	if view != nil {
 		htmlID := container.htmlID()
 		view.setParentID(htmlID)
-		if container.views == nil || len(container.views) == 0 {
+		if len(container.views) == 0 {
 			container.views = []View{view}
 		} else {
 			container.views = append(container.views, view)

wasmBridge.go

@@ -193,6 +193,17 @@ func (bridge *wasmBridge) createCanvasVar(funcName string, args ...any) any {
 	return result
 }
 
+func (bridge *wasmBridge) createPath2D(arg string) any {
+	if arg != "" {
+		result := bridge.canvas.Call("createPath2D", arg)
+		bridge.printFuncToLog("var "+result.String()+" = new Path2D", arg)
+		return result
+	}
+	result := bridge.canvas.Call("createPath2D")
+	bridge.printFuncToLog("var " + result.String() + " = new Path2D")
+	return result
+}
+
 func (bridge *wasmBridge) updateCanvasProperty(property string, value any) {
 	if !bridge.canvas.IsNull() {
 		if ProtocolInDebugLog {

webBridge.go

@@ -350,6 +350,20 @@ func (bridge *webBridge) createCanvasVar(funcName string, args ...any) any {
 	return result
 }
 
+func (bridge *webBridge) createPath2D(arg string) any {
+	bridge.canvasVarNumber++
+	result := canvasVar{name: fmt.Sprintf("v%d", bridge.canvasVarNumber)}
+	bridge.canvasBuffer.WriteString("\nlet ")
+	bridge.canvasBuffer.WriteString(result.name)
+	bridge.canvasBuffer.WriteString(` = new Path2D(`)
+	if arg != "" {
+		argText, _ := bridge.argToString(arg)
+		bridge.canvasBuffer.WriteString(argText)
+	}
+	bridge.canvasBuffer.WriteString(`);`)
+	return result
+}
+
 func (bridge *webBridge) callCanvasVarFunc(v any, funcName string, args ...any) {
 	varName, ok := v.(canvasVar)
 	if !ok {