Fix return types for most methods

src/jcanvas.d.ts

@@ -139,30 +139,30 @@ interface JQuery {
 	stopLayer(layerId: JCanvasLayerId, clearQueue?: boolean): void;
 	stopLayerGroup(groupId: jCanvasLayerGroupId, clearQueue?: boolean): void;
 	draw(args: Partial<JCanvasObject>): JQuery;
-	clearCanvas(args?: JCanvasObject): void;
-	saveCanvas(args?: JCanvasObject): void;
-	restoreCanvas(args?: JCanvasObject): void;
-	rotateCanvas(args?: JCanvasObject): void;
-	scaleCanvas(args?: JCanvasObject): void;
-	translateCanvas(args?: JCanvasObject): void;
-	drawRect(args: Partial<JCanvasObject>): void;
-	drawArc(args: Partial<JCanvasObject>): void;
-	drawEllipse(args: Partial<JCanvasObject>): void;
-	drawPolygon(args: Partial<JCanvasObject>): void;
-	drawSlice(args: Partial<JCanvasObject>): void;
-	drawLine(args: Partial<JCanvasObject>): void;
-	drawQuadratic(args: Partial<JCanvasObject>): void;
-	drawBezier(args: Partial<JCanvasObject>): void;
-	drawVector(args: Partial<JCanvasObject>): void;
-	drawPath(args: Partial<JCanvasObject>): void;
-	drawText(args: Partial<JCanvasObject>): void;
-	measureText(args: JCanvasLayerId): void;
-	drawImage(args: Partial<JCanvasObject>): void;
-	createPattern(args: Partial<JCanvasObject>): void;
-	createGradient(args: Partial<JCanvasObject>): void;
+	clearCanvas(args?: JCanvasObject): JQuery;
+	saveCanvas(args?: JCanvasObject): JQuery;
+	restoreCanvas(args?: JCanvasObject): JQuery;
+	rotateCanvas(args?: JCanvasObject): JQuery;
+	scaleCanvas(args?: JCanvasObject): JQuery;
+	translateCanvas(args?: JCanvasObject): JQuery;
+	drawRect(args: Partial<JCanvasObject>): JQuery;
+	drawArc(args: Partial<JCanvasObject>): JQuery;
+	drawEllipse(args: Partial<JCanvasObject>): JQuery;
+	drawPolygon(args: Partial<JCanvasObject>): JQuery;
+	drawSlice(args: Partial<JCanvasObject>): JQuery;
+	drawLine(args: Partial<JCanvasObject>): JQuery;
+	drawQuadratic(args: Partial<JCanvasObject>): JQuery;
+	drawBezier(args: Partial<JCanvasObject>): JQuery;
+	drawVector(args: Partial<JCanvasObject>): JQuery;
+	drawPath(args: Partial<JCanvasObject>): JQuery;
+	drawText(args: Partial<JCanvasObject>): JQuery;
+	measureText(args: JCanvasLayerId): JCanvasObject;
+	drawImage(args: Partial<JCanvasObject>): JQuery;
+	createPattern(args: Partial<JCanvasObject>): CanvasPattern | null;
+	createGradient(args: Partial<JCanvasObject>): CanvasGradient | null;
 	setPixels(args: Partial<JCanvasObject>): void;
-	getCanvasImage(type: string, quality?: number): void;
-	detectPixelRatio(callback?: (ratio: number) => void): void;
+	getCanvasImage(type: string, quality?: number): string | null;
+	detectPixelRatio(callback?: (ratio: number) => void): JQuery;
 }
 
 interface JCanvasDefaults {

src/jcanvas.ts

@@ -4325,11 +4325,11 @@ $.fn.createGradient = function createGradient(args) {
 	const params = new jCanvasObject(args);
 	const canvas = $canvases[0];
 	if (!_isCanvas(canvas)) {
-		return;
+		return null;
 	}
 	const ctx = _getContext(canvas);
 	if (!ctx) {
-		return;
+		return null;
 	}
 	// Gradient coordinates must be defined
 	params.x1 = params.x1 || 0;