Multiline text everywhere

README.md

@@ -29,6 +29,8 @@ Gremlin -> Bowie: Do what?
 Bowie -> Gremlin: Remind me of the babe!
 
 Bowie -> Audience: Sings
+
+terminators box
 ```
 
 ### Connection Types
@@ -62,12 +64,13 @@ Foo <- ]: From the right
 <img src="screenshots/NotesAndState.png" alt="Notes and State preview" width="150" align="right" />
 
 ```
-title Note placements
+title Note Placements
 
 note over Foo: Foo says something
 note left of Foo: Stuff
 note right of Bar: More stuff
-note over Foo, Bar: Foo and Bar
+note over Foo, Bar: "Foo and Bar
+on multiple lines"
 note between Foo, Bar: Link
 
 state over Foo: Foo is ponderous
@@ -78,7 +81,7 @@ state over Foo: Foo is ponderous
 <img src="screenshots/Logic.png" alt="Logic preview" width="200" align="right" />
 
 ```
-title At the bank
+title At the Bank
 
 begin Person, ATM, Bank
 Person -> ATM: Request money
@@ -97,6 +100,25 @@ else
 end
 ```
 
+### Multiline Text
+
+<img src="screenshots/MultilineText.png" alt="Multiline Text preview" width="150" align="right" />
+
+```
+title 'My Multiline
+Title'
+
+note over Foo: 'Also possible\nwith escapes'
+
+Foo -> Bar: 'Lines of text\non this arrow'
+
+if 'Even multiline\ninside conditions like this'
+  Foo -> 'Multiline\nagent'
+end
+
+state over Foo: 'Newlines here,\ntoo!'
+```
+
 ### Short-Lived Agents
 
 <img src="screenshots/ShortLivedAgents.png" alt="Short Lived Agents preview" width="200" align="right" />

scripts/sequence/Renderer.js

@@ -2,58 +2,62 @@ define([
 	'./ArrayUtilities',
 	'./SVGUtilities',
 	'./SVGTextBlock',
+	'./SVGShapes',
 ], (
 	array,
 	svg,
-	SVGTextBlock
+	SVGTextBlock,
+	SVGShapes
 ) => {
 	'use strict';
 
-	function boxRenderer(attrs, position) {
-		return svg.make('rect', Object.assign({}, position, attrs));
-	}
-
-	function noteRenderer(attrs, flickAttrs, position) {
-		const g = svg.make('g');
-		const x0 = position.x;
-		const x1 = position.x + position.width;
-		const y0 = position.y;
-		const y1 = position.y + position.height;
-		const flick = 7;
-
-		g.appendChild(svg.make('path', Object.assign({
-			'd': (
-				'M ' + x0 + ' ' + y0 +
-				' L ' + (x1 - flick) + ' ' + y0 +
-				' L ' + x1 + ' ' + (y0 + flick) +
-				' L ' + x1 + ' ' + y1 +
-				' L ' + x0 + ' ' + y1 +
-				' Z'
-			),
-		}, attrs)));
-
-		g.appendChild(svg.make('path', Object.assign({
-			'd': (
-				'M ' + (x1 - flick) + ' ' + y0 +
-				' L ' + (x1 - flick) + ' ' + (y0 + flick) +
-				' L ' + x1 + ' ' + (y0 + flick)
-			),
-		}, flickAttrs)));
-
-		return g;
-	}
-
 	const SEP_ZERO = {left: 0, right: 0};
 
 	const LINE_HEIGHT = 1.3;
 	const TITLE_MARGIN = 10;
 	const OUTER_MARGIN = 5;
-	const AGENT_BOX_PADDING = 10;
 	const AGENT_MARGIN = 10;
-	const AGENT_CROSS_SIZE = 20;
-	const AGENT_NONE_HEIGHT = 10;
 	const ACTION_MARGIN = 5;
 
+	const AGENT_CAP = {
+		box: {
+			padding: {
+				top: 5,
+				left: 10,
+				right: 10,
+				bottom: 5,
+			},
+			boxAttrs: {
+				'fill': '#FFFFFF',
+				'stroke': '#000000',
+				'stroke-width': 1,
+			},
+			labelAttrs: {
+				'font-family': 'sans-serif',
+				'font-size': 12,
+				'line-height': LINE_HEIGHT,
+				'text-anchor': 'middle',
+			},
+		},
+		cross: {
+			size: 20,
+			attrs: {
+				'fill': 'none',
+				'stroke': '#000000',
+				'stroke-width': 1,
+			},
+		},
+		bar: {
+			attrs: {
+				'fill': '#000000',
+				'height': 5,
+			},
+		},
+		none: {
+			height: 10,
+		},
+	};
+
 	const CONNECT = {
 		lineAttrs: {
 			'solid': {
@@ -84,12 +88,18 @@ define([
 			attrs: {
 				'font-family': 'sans-serif',
 				'font-size': 8,
+				'line-height': LINE_HEIGHT,
 				'text-anchor': 'middle',
 			},
 		},
 		mask: {
-			padding: 3,
+			padding: {
-			attrs: {
+				top: 0,
+				left: 3,
+				right: 3,
+				bottom: 0,
+			},
+			maskAttrs: {
 				'fill': '#FFFFFF',
 			},
 		},
@@ -130,24 +140,24 @@ define([
 					'font-family': 'sans-serif',
 					'font-weight': 'bold',
 					'font-size': 9,
+					'line-height': LINE_HEIGHT,
 					'text-anchor': 'left',
 				},
 			},
 			label: {
-				maskPadding: {
+				padding: {
-					left: 3,
+					top: 1,
+					left: 5,
 					right: 3,
+					bottom: 0,
 				},
 				maskAttrs: {
 					'fill': '#FFFFFF',
 				},
-				labelPadding: {
-					left: 5,
-					right: 5,
-				},
 				labelAttrs: {
 					'font-family': 'sans-serif',
 					'font-size': 8,
+					'line-height': LINE_HEIGHT,
 					'text-anchor': 'left',
 				},
 			},
@@ -166,7 +176,7 @@ define([
 			margin: {top: 0, left: 5, right: 5, bottom: 0},
 			padding: {top: 5, left: 5, right: 10, bottom: 5},
 			overlap: {left: 10, right: 10},
-			boxRenderer: noteRenderer.bind(null, {
+			boxRenderer: SVGShapes.renderNote.bind(null, {
 				'fill': '#FFFFFF',
 				'stroke': '#000000',
 				'stroke-width': 1,
@@ -178,13 +188,14 @@ define([
 			labelAttrs: {
 				'font-family': 'sans-serif',
 				'font-size': 8,
+				'line-height': LINE_HEIGHT,
 			},
 		},
 		'state': {
 			margin: {top: 0, left: 5, right: 5, bottom: 0},
 			padding: {top: 7, left: 7, right: 7, bottom: 7},
 			overlap: {left: 10, right: 10},
-			boxRenderer: boxRenderer.bind(null, {
+			boxRenderer: SVGShapes.renderBox.bind(null, {
 				'fill': '#FFFFFF',
 				'stroke': '#000000',
 				'stroke-width': 1,
@@ -194,6 +205,7 @@ define([
 			labelAttrs: {
 				'font-family': 'sans-serif',
 				'font-size': 8,
+				'line-height': LINE_HEIGHT,
 			},
 		},
 	};
@@ -202,6 +214,7 @@ define([
 		TITLE: {
 			'font-family': 'sans-serif',
 			'font-size': 20,
+			'line-height': LINE_HEIGHT,
 			'text-anchor': 'middle',
 			'class': 'title',
 		},
@@ -211,28 +224,21 @@ define([
 			'stroke': '#000000',
 			'stroke-width': 1,
 		},
-		AGENT_BOX: {
-			'fill': '#FFFFFF',
-			'stroke': '#000000',
-			'stroke-width': 1,
-			'height': 24,
-		},
-		AGENT_BOX_LABEL: {
-			'font-family': 'sans-serif',
-			'font-size': 12,
-			'text-anchor': 'middle',
-		},
-		AGENT_CROSS: {
-			'fill': 'none',
-			'stroke': '#000000',
-			'stroke-width': 1,
-		},
-		AGENT_BAR: {
-			'fill': '#000000',
-			'height': 5,
-		},
 	};
 
+	function drawHorizontalArrowHead(container, {x, y, dx, dy, attrs}) {
+		container.appendChild(svg.make(
+			attrs.fill === 'none' ? 'polyline' : 'polygon',
+			Object.assign({
+				'points': (
+					(x + dx) + ' ' + (y - dy) + ' ' +
+					x + ' ' + y + ' ' +
+					(x + dx) + ' ' + (y + dy)
+				),
+			}, attrs)
+		));
+	}
+
 	function traverse(stages, callbacks) {
 		stages.forEach((stage) => {
 			if(stage.type === 'block') {
@@ -321,19 +327,20 @@ define([
 			});
 
 			this.agentLines = svg.make('g');
+			this.mask = svg.make('g');
 			this.blocks = svg.make('g');
 			this.sections = svg.make('g');
-			this.agentDecor = svg.make('g');
+			this.actionShapes = svg.make('g');
-			this.actions = svg.make('g');
+			this.actionLabels = svg.make('g');
 			this.base.appendChild(this.agentLines);
+			this.base.appendChild(this.mask);
 			this.base.appendChild(this.blocks);
 			this.base.appendChild(this.sections);
-			this.base.appendChild(this.agentDecor);
+			this.base.appendChild(this.actionShapes);
-			this.base.appendChild(this.actions);
+			this.base.appendChild(this.actionLabels);
-			this.title = new SVGTextBlock(this.base, ATTRS.TITLE, LINE_HEIGHT);
+			this.title = new SVGTextBlock(this.base, ATTRS.TITLE);
 
-			this.testers = svg.make('g');
+			this.sizer = new SVGTextBlock.SizeTester(this.base);
-			this.testersCache = new Map();
 		}
 
 		findExtremes(agents) {
@@ -384,24 +391,36 @@ define([
 			});
 		}
 
-		separationAgentCapBox(agentInfo) {
+		separationAgentCapBox({label}) {
+			const width = (
+				this.sizer.measure(AGENT_CAP.box.labelAttrs, label).width +
+				AGENT_CAP.box.padding.left +
+				AGENT_CAP.box.padding.right
+			);
+
 			return {
-				left: agentInfo.labelWidth / 2,
+				left: width / 2,
-				right: agentInfo.labelWidth / 2,
+				right: width / 2,
 			};
 		}
 
 		separationAgentCapCross() {
 			return {
-				left: AGENT_CROSS_SIZE / 2,
+				left: AGENT_CAP.cross.size / 2,
-				right: AGENT_CROSS_SIZE / 2,
+				right: AGENT_CAP.cross.size / 2,
 			};
 		}
 
-		separationAgentCapBar(agentInfo) {
+		separationAgentCapBar({label}) {
+			const width = (
+				this.sizer.measure(AGENT_CAP.box.labelAttrs, label).width +
+				AGENT_CAP.box.padding.left +
+				AGENT_CAP.box.padding.right
+			);
+
 			return {
-				left: agentInfo.labelWidth / 2,
+				left: width / 2,
-				right: agentInfo.labelWidth / 2,
+				right: width / 2,
 			};
 		}
 
@@ -432,7 +451,7 @@ define([
 				agents[0],
 				agents[1],
 
-				this.testTextWidth(CONNECT.label.attrs, label) +
+				this.sizer.measure(CONNECT.label.attrs, label).width +
 				CONNECT.arrow.width * 2 +
 				CONNECT.label.padding * 2 +
 				ATTRS.AGENT_LINE['stroke-width']
@@ -442,7 +461,7 @@ define([
 		separationNoteOver({agents, mode, label}) {
 			const config = NOTE[mode];
 			const width = (
-				this.testTextWidth(config.labelAttrs, label) +
+				this.sizer.measure(config.labelAttrs, label).width +
 				config.padding.left +
 				config.padding.right
 			);
@@ -478,7 +497,7 @@ define([
 			const agentSpaces = new Map();
 			agentSpaces.set(left, {
 				left: (
-					this.testTextWidth(config.labelAttrs, label) +
+					this.sizer.measure(config.labelAttrs, label).width +
 					config.padding.left +
 					config.padding.right +
 					config.margin.left +
@@ -497,7 +516,7 @@ define([
 			agentSpaces.set(right, {
 				left: 0,
 				right: (
-					this.testTextWidth(config.labelAttrs, label) +
+					this.sizer.measure(config.labelAttrs, label).width +
 					config.padding.left +
 					config.padding.right +
 					config.margin.left +
@@ -515,7 +534,7 @@ define([
 				left,
 				right,
 
-				this.testTextWidth(config.labelAttrs, label) +
+				this.sizer.measure(config.labelAttrs, label).width +
 				config.padding.left +
 				config.padding.right +
 				config.margin.left +
@@ -529,13 +548,14 @@ define([
 		}
 
 		separationSectionBegin(scope, {left, right}, {mode, label}) {
+			const config = BLOCK.section;
 			const width = (
-				this.testTextWidth(BLOCK.section.mode.labelAttrs, mode) +
+				this.sizer.measure(config.mode.labelAttrs, mode).width +
-				BLOCK.section.mode.padding.left +
+				config.mode.padding.left +
-				BLOCK.section.mode.padding.right +
+				config.mode.padding.right +
-				this.testTextWidth(BLOCK.section.label.labelAttrs, label) +
+				this.sizer.measure(config.label.labelAttrs, label).width +
-				BLOCK.section.label.labelPadding.left +
+				config.label.padding.left +
-				BLOCK.section.label.labelPadding.right
+				config.label.padding.right
 			);
 			this.addSeparation(left, right, width);
 		}
@@ -548,42 +568,36 @@ define([
 			this.separationAction[stage.type](stage);
 		}
 
-		renderAgentCapBox({x, labelWidth, label}) {
+		renderAgentCapBox({x, label}) {
-			this.agentDecor.appendChild(svg.make('rect', Object.assign({
+			const {height} = SVGShapes.renderBoxedText(label, {
-				'x': x - labelWidth / 2,
+				x,
-				'y': this.currentY,
+				y: this.currentY,
-				'width': labelWidth,
+				padding: AGENT_CAP.box.padding,
-			}, ATTRS.AGENT_BOX)));
+				boxAttrs: AGENT_CAP.box.boxAttrs,
-
+				labelAttrs: AGENT_CAP.box.labelAttrs,
-			const name = svg.make('text', Object.assign({
+				boxLayer: this.actionShapes,
-				'x': x,
+				labelLayer: this.actionLabels,
-				'y': this.currentY + (
+			});
-					ATTRS.AGENT_BOX.height +
-					ATTRS.AGENT_BOX_LABEL['font-size'] * (2 - LINE_HEIGHT)
-				) / 2,
-			}, ATTRS.AGENT_BOX_LABEL));
-			name.appendChild(svg.makeText(label));
-			this.agentDecor.appendChild(name);
 
 			return {
 				lineTop: 0,
-				lineBottom: ATTRS.AGENT_BOX.height,
+				lineBottom: height,
-				height: ATTRS.AGENT_BOX.height,
+				height,
 			};
 		}
 
 		renderAgentCapCross({x}) {
 			const y = this.currentY;
-			const d = AGENT_CROSS_SIZE / 2;
+			const d = AGENT_CAP.cross.size / 2;
 
-			this.agentDecor.appendChild(svg.make('path', Object.assign({
+			this.actionShapes.appendChild(svg.make('path', Object.assign({
 				'd': (
 					'M ' + (x - d) + ' ' + y +
 					' L ' + (x + d) + ' ' + (y + d * 2) +
 					' M ' + (x + d) + ' ' + y +
 					' L ' + (x - d) + ' ' + (y + d * 2)
 				),
-			}, ATTRS.AGENT_CROSS)));
+			}, AGENT_CAP.cross.attrs)));
 
 			return {
 				lineTop: d,
@@ -592,124 +606,115 @@ define([
 			};
 		}
 
-		renderAgentCapBar({x, labelWidth}) {
+		renderAgentCapBar({x, label}) {
-			this.agentDecor.appendChild(svg.make('rect', Object.assign({
+			const width = (
-				'x': x - labelWidth / 2,
+				this.sizer.measure(AGENT_CAP.box.labelAttrs, label).width +
+				AGENT_CAP.box.padding.left +
+				AGENT_CAP.box.padding.right
+			);
+
+			this.actionShapes.appendChild(svg.make('rect', Object.assign({
+				'x': x - width / 2,
 				'y': this.currentY,
-				'width': labelWidth,
+				'width': width,
-			}, ATTRS.AGENT_BAR)));
+			}, AGENT_CAP.bar.attrs)));
 
 			return {
 				lineTop: 0,
-				lineBottom: ATTRS.AGENT_BAR.height,
+				lineBottom: AGENT_CAP.bar.attrs.height,
-				height: ATTRS.AGENT_BAR.height,
+				height: AGENT_CAP.bar.attrs.height,
 			};
 		}
 
 		renderAgentCapNone() {
 			return {
-				lineTop: AGENT_NONE_HEIGHT,
+				lineTop: AGENT_CAP.none.height,
 				lineBottom: 0,
-				height: AGENT_NONE_HEIGHT,
+				height: AGENT_CAP.none.height,
 			};
 		}
 
 		renderAgentBegin({mode, agents}) {
-			let shifts = {height: 0};
+			let maxHeight = 0;
 			agents.forEach((agent) => {
 				const agentInfo = this.agentInfos.get(agent);
-				shifts = this.renderAgentCap[mode](agentInfo);
+				const shifts = this.renderAgentCap[mode](agentInfo);
+				maxHeight = Math.max(maxHeight, shifts.height);
 				agentInfo.latestYStart = this.currentY + shifts.lineBottom;
 			});
-			this.currentY += shifts.height + ACTION_MARGIN;
+			this.currentY += maxHeight + ACTION_MARGIN;
 		}
 
 		renderAgentEnd({mode, agents}) {
-			let shifts = {height: 0};
+			let maxHeight = 0;
 			agents.forEach((agent) => {
 				const agentInfo = this.agentInfos.get(agent);
 				const x = agentInfo.x;
-				shifts = this.renderAgentCap[mode](agentInfo);
+				const shifts = this.renderAgentCap[mode](agentInfo);
-				this.agentLines.appendChild(svg.make('path', Object.assign({
+				maxHeight = Math.max(maxHeight, shifts.height);
-					'd': (
+				this.agentLines.appendChild(svg.make('line', Object.assign({
-						'M ' + x + ' ' + agentInfo.latestYStart +
+					'x1': x,
-						' L ' + x + ' ' + (this.currentY + shifts.lineTop)
+					'y1': agentInfo.latestYStart,
-					),
+					'x2': x,
+					'y2': this.currentY + shifts.lineTop,
 					'class': 'agent-' + agentInfo.index + '-line',
 				}, ATTRS.AGENT_LINE)));
 				agentInfo.latestYStart = null;
 			});
-			this.currentY += shifts.height + ACTION_MARGIN;
+			this.currentY += maxHeight + ACTION_MARGIN;
 		}
 
 		renderConnection({label, agents, line, left, right}) {
-			/* jshint -W074, -W071 */ // TODO: tidy this up
 			const from = this.agentInfos.get(agents[0]);
 			const to = this.agentInfos.get(agents[1]);
 
 			const dy = CONNECT.arrow.height / 2;
-			const dx = CONNECT.arrow.width;
 			const dir = (from.x < to.x) ? 1 : -1;
 			const short = ATTRS.AGENT_LINE['stroke-width'];
-			let y = this.currentY;
 
-			if(label) {
+			const height = (
-				const mask = svg.make('rect', CONNECT.mask.attrs);
+				this.sizer.measureHeight(CONNECT.label.attrs, label) +
-				const labelNode = svg.make('text', CONNECT.label.attrs);
-				labelNode.appendChild(svg.makeText(label));
-				const sz = CONNECT.label.attrs['font-size'];
-				this.actions.appendChild(mask);
-				this.actions.appendChild(labelNode);
-				y += Math.max(
-					dy,
 				CONNECT.label.margin.top +
-					sz * LINE_HEIGHT +
 				CONNECT.label.margin.bottom
 			);
-				const w = labelNode.getComputedTextLength();
-				const x = (from.x + to.x) / 2;
-				const yBase = (
-					y -
-					sz * (LINE_HEIGHT - 1) -
-					CONNECT.label.margin.bottom
-				);
-				labelNode.setAttribute('x', x);
-				labelNode.setAttribute('y', yBase);
-				mask.setAttribute('x', x - w / 2 - CONNECT.mask.padding);
-				mask.setAttribute('y', yBase - sz);
-				mask.setAttribute('width', w + CONNECT.mask.padding * 2);
-				mask.setAttribute('height', sz * LINE_HEIGHT);
-			} else {
-				y += dy;
-			}
 
-			this.actions.appendChild(svg.make('path', Object.assign({
+			let y = this.currentY + Math.max(dy, height);
-				'd': (
+
-					'M ' + (from.x + (left ? short : 0) * dir) + ' ' + y +
+			SVGShapes.renderBoxedText(label, {
-					' L ' + (to.x - (right ? short : 0) * dir) + ' ' + y
+				x: (from.x + to.x) / 2,
-				),
+				y: y - height + CONNECT.label.margin.top,
+				padding: CONNECT.mask.padding,
+				boxAttrs: CONNECT.mask.maskAttrs,
+				labelAttrs: CONNECT.label.attrs,
+				boxLayer: this.mask,
+				labelLayer: this.actionLabels,
+			});
+
+			this.actionShapes.appendChild(svg.make('line', Object.assign({
+				'x1': from.x + (left ? short : 0) * dir,
+				'y1': y,
+				'x2': to.x - (right ? short : 0) * dir,
+				'y2': y,
 			}, CONNECT.lineAttrs[line])));
 
 			if(left) {
-				this.actions.appendChild(svg.make('path', Object.assign({
+				drawHorizontalArrowHead(this.actionShapes, {
-					'd': (
+					x: from.x + short * dir,
-						'M ' + (from.x + (dx + short) * dir) + ' ' + (y - dy) +
+					y,
-						' L ' + (from.x + short * dir) + ' ' + y +
+					dx: CONNECT.arrow.width * dir,
-						' L ' + (from.x + (dx + short) * dir) + ' ' + (y + dy) +
+					dy,
-						(CONNECT.arrow.attrs.fill === 'none' ? '' : ' Z')
+					attrs: CONNECT.arrow.attrs,
-					),
+				});
-				}, CONNECT.arrow.attrs)));
 			}
 
 			if(right) {
-				this.actions.appendChild(svg.make('path', Object.assign({
+				drawHorizontalArrowHead(this.actionShapes, {
-					'd': (
+					x: to.x - short * dir,
-						'M ' + (to.x - (dx + short) * dir) + ' ' + (y - dy) +
+					y,
-						' L ' + (to.x - short * dir) + ' ' + y +
+					dx: -CONNECT.arrow.width * dir,
-						' L ' + (to.x - (dx + short) * dir) + ' ' + (y + dy) +
+					dy,
-						(CONNECT.arrow.attrs.fill === 'none' ? '' : ' Z')
+					attrs: CONNECT.arrow.attrs,
-					),
+				});
-				}, CONNECT.arrow.attrs)));
 			}
 
 			this.currentY = y + dy + ACTION_MARGIN;
@@ -718,19 +723,25 @@ define([
 		renderNote({xMid = null, x0 = null, x1 = null}, anchor, mode, label) {
 			const config = NOTE[mode];
 
-			const sz = config.labelAttrs['font-size'];
-
 			this.currentY += config.margin.top;
 
-			const labelNode = svg.make('text', Object.assign({
+			const y = this.currentY + config.padding.top;
-				'y': this.currentY + config.padding.top + sz,
+			const labelNode = new SVGTextBlock(
-				'text-anchor': anchor,
+				this.actionLabels,
-			}, config.labelAttrs));
+				config.labelAttrs,
-			labelNode.appendChild(svg.makeText(label));
+				{text: label, y}
-			this.actions.appendChild(labelNode);
+			);
 
-			const w = labelNode.getComputedTextLength();
+			const fullW = (
-			const fullW = w + config.padding.left + config.padding.right;
+				labelNode.width +
+				config.padding.left +
+				config.padding.right
+			);
+			const fullH = (
+				config.padding.top +
+				labelNode.height +
+				config.padding.bottom
+			);
 			if(x0 === null && xMid !== null) {
 				x0 = xMid - fullW / 2;
 			}
@@ -739,35 +750,30 @@ define([
 			} else if(x0 === null) {
 				x0 = x1 - fullW;
 			}
-			switch(anchor) {
+			switch(config.labelAttrs['text-anchor']) {
-			case 'start':
+			case 'middle':
-				labelNode.setAttribute('x', x0 + config.padding.left);
+				labelNode.reanchor((
-				break;
-			case 'end':
-				labelNode.setAttribute('x', x1 - config.padding.right);
-				break;
-			default:
-				labelNode.setAttribute('x', (
 					x0 + config.padding.left +
 					x1 - config.padding.right
-				) / 2);
+				) / 2, y);
+				break;
+			case 'end':
+				labelNode.reanchor(x1 - config.padding.right, y);
+				break;
+			default:
+				labelNode.reanchor(x0 + config.padding.left, y);
+				break;
 			}
 
-			this.actions.insertBefore(config.boxRenderer({
+			this.actionShapes.appendChild(config.boxRenderer({
 				x: x0,
 				y: this.currentY,
 				width: x1 - x0,
-				height: (
+				height: fullH,
-					config.padding.top +
+			}));
-					sz * LINE_HEIGHT +
-					config.padding.bottom
-				),
-			}), labelNode);
 
 			this.currentY += (
-				config.padding.top +
+				fullH +
-				sz * LINE_HEIGHT +
-				config.padding.bottom +
 				config.margin.bottom +
 				ACTION_MARGIN
 			);
@@ -822,8 +828,6 @@ define([
 		}
 
 		renderSectionBegin(scope, {left, right}, {mode, label}) {
-			/* jshint -W071 */ // TODO: tidy this up (split text rendering)
-
 			const agentInfoL = this.agentInfos.get(left);
 			const agentInfoR = this.agentInfos.get(right);
 
@@ -831,71 +835,38 @@ define([
 				scope.first = false;
 			} else {
 				this.currentY += BLOCK.section.padding.bottom;
-				this.sections.appendChild(svg.make('path', Object.assign({
+				this.sections.appendChild(svg.make('line', Object.assign({
-					'd': (
+					'x1': agentInfoL.x,
-						'M' + agentInfoL.x + ' ' + this.currentY +
+					'y1': this.currentY,
-						' L' + agentInfoR.x + ' ' + this.currentY
+					'x2': agentInfoR.x,
-					),
+					'y2': this.currentY,
 				}, BLOCK.separator.attrs)));
 			}
 
-			let x = agentInfoL.x;
+			const modeRender = SVGShapes.renderBoxedText(mode, {
-			if(mode) {
+				x: agentInfoL.x,
-				const sz = BLOCK.section.mode.labelAttrs['font-size'];
+				y: this.currentY,
-				const modeBox = svg.make('rect', Object.assign({
+				padding: BLOCK.section.mode.padding,
-					'x': x,
+				boxAttrs: BLOCK.section.mode.boxAttrs,
-					'y': this.currentY,
+				labelAttrs: BLOCK.section.mode.labelAttrs,
-					'height': (
+				boxLayer: this.blocks,
-						sz * LINE_HEIGHT +
+				labelLayer: this.actionLabels,
-						BLOCK.section.mode.padding.top +
+			});
-						BLOCK.section.mode.padding.bottom
+
-					),
+			const labelRender = SVGShapes.renderBoxedText(label, {
-				}, BLOCK.section.mode.boxAttrs));
+				x: agentInfoL.x + modeRender.width,
-				const modeLabel = svg.make('text', Object.assign({
+				y: this.currentY,
-					'x': x + BLOCK.section.mode.padding.left,
+				padding: BLOCK.section.label.padding,
-					'y': (
+				boxAttrs: BLOCK.section.label.maskAttrs,
-						this.currentY + sz +
+				labelAttrs: BLOCK.section.label.labelAttrs,
-						BLOCK.section.mode.padding.top
+				boxLayer: this.mask,
-					),
+				labelLayer: this.actionLabels,
-				}, BLOCK.section.mode.labelAttrs));
+			});
-				modeLabel.appendChild(svg.makeText(mode));
+
-				this.blocks.appendChild(modeBox);
+			this.currentY += (
-				this.actions.appendChild(modeLabel);
+				Math.max(modeRender.height, labelRender.height) +
-				const w = (
+				BLOCK.section.padding.top
-					modeLabel.getComputedTextLength() +
-					BLOCK.section.mode.padding.left +
-					BLOCK.section.mode.padding.right
 			);
-				modeBox.setAttribute('width', w);
-				x += w;
-
-				this.currentY += sz * LINE_HEIGHT;
-			}
-
-			if(label) {
-				x += BLOCK.section.label.labelPadding.left;
-				const sz = BLOCK.section.label.labelAttrs['font-size'];
-				const mask = svg.make('rect', Object.assign({
-					'x': x - BLOCK.section.label.maskPadding.left,
-					'y': this.currentY - sz * LINE_HEIGHT,
-					'height': sz * LINE_HEIGHT,
-				}, BLOCK.section.label.maskAttrs));
-				const labelLabel = svg.make('text', Object.assign({
-					'x': x,
-					'y': this.currentY - sz * (LINE_HEIGHT - 1),
-				}, BLOCK.section.label.labelAttrs));
-				labelLabel.appendChild(svg.makeText(label));
-				this.actions.appendChild(mask);
-				this.actions.appendChild(labelLabel);
-				const w = (
-					labelLabel.getComputedTextLength() +
-					BLOCK.section.label.maskPadding.left +
-					BLOCK.section.label.maskPadding.right
-				);
-				mask.setAttribute('width', w);
-			}
-
-			this.currentY += BLOCK.section.padding.top;
 		}
 
 		renderSectionEnd(/*scope, block, section*/) {
@@ -920,46 +891,20 @@ define([
 			this.renderAction[stage.type](stage);
 		}
 
-		testTextWidth(attrs, content) {
-			let tester = this.testersCache.get(attrs);
-			if(!tester) {
-				const text = svg.makeText();
-				const node = svg.make('text', attrs);
-				node.appendChild(text);
-				this.testers.appendChild(node);
-				tester = {text, node};
-				this.testersCache.set(attrs, tester);
-			}
-
-			tester.text.nodeValue = content;
-			return tester.node.getComputedTextLength();
-		}
-
 		buildAgentInfos(agents, stages) {
-			svg.empty(this.testers);
-			this.testersCache.clear();
-			this.base.appendChild(this.testers);
-
 			this.agentInfos = new Map();
 			agents.forEach((agent, index) => {
 				this.agentInfos.set(agent, {
 					label: agent,
-					labelWidth: (
-						this.testTextWidth(ATTRS.AGENT_BOX_LABEL, agent) +
-						AGENT_BOX_PADDING * 2
-					),
 					index,
 					x: null,
 					latestYStart: null,
 					separations: new Map(),
 				});
 			});
-			this.agentInfos.get('[').labelWidth = 0;
-			this.agentInfos.get(']').labelWidth = 0;
 
 			this.visibleAgents = ['[', ']'];
 			traverse(stages, this.separationTraversalFns);
-			this.base.removeChild(this.testers);
 
 			agents.forEach((agent) => {
 				const agentInfo = this.agentInfos.get(agent);
@@ -999,10 +944,11 @@ define([
 
 		render({meta, agents, stages}) {
 			svg.empty(this.agentLines);
+			svg.empty(this.mask);
 			svg.empty(this.blocks);
 			svg.empty(this.sections);
-			svg.empty(this.agentDecor);
+			svg.empty(this.actionShapes);
-			svg.empty(this.actions);
+			svg.empty(this.actionLabels);
 
 			this.title.setText(meta.title);
 
@@ -1015,6 +961,9 @@ define([
 
 			const stagesHeight = Math.max(this.currentY - ACTION_MARGIN, 0);
 			this.updateBounds(stagesHeight);
+
+			this.sizer.resetCache();
+			this.sizer.detach();
 		}
 
 		getAgentX(name) {

scripts/sequence/Renderer_spec.js

@@ -59,7 +59,7 @@ defineDescribe('Sequence Renderer', ['./Renderer'], (Renderer) => {
 
 			const element = renderer.svg();
 			const line = element.getElementsByClassName('agent-1-line')[0];
-			const drawnX = Number(line.getAttribute('d').split(' ')[1]);
+			const drawnX = Number(line.getAttribute('x1'));
 
 			expect(drawnX).toEqual(renderer.getAgentX('A'));
 		});

scripts/sequence/SVGShapes.js

@@ -0,0 +1,108 @@
+define(['./SVGUtilities', './SVGTextBlock'], (svg, SVGTextBlock) => {
+	'use strict';
+
+	function renderBox(attrs, position) {
+		return svg.make('rect', Object.assign({}, position, attrs));
+	}
+
+	function renderNote(attrs, flickAttrs, position) {
+		const g = svg.make('g');
+		const x0 = position.x;
+		const x1 = position.x + position.width;
+		const y0 = position.y;
+		const y1 = position.y + position.height;
+		const flick = 7;
+
+		g.appendChild(svg.make('polygon', Object.assign({
+			'points': (
+				x0 + ' ' + y0 + ' ' +
+				(x1 - flick) + ' ' + y0 + ' ' +
+				x1 + ' ' + (y0 + flick) + ' ' +
+				x1 + ' ' + y1 + ' ' +
+				x0 + ' ' + y1
+			),
+		}, attrs)));
+
+		g.appendChild(svg.make('polyline', Object.assign({
+			'points': (
+				(x1 - flick) + ' ' + y0 + ' ' +
+				(x1 - flick) + ' ' + (y0 + flick) + ' ' +
+				x1 + ' ' + (y0 + flick)
+			),
+		}, flickAttrs)));
+
+		return g;
+	}
+
+	function renderBoxedText(text, {
+		x,
+		y,
+		padding,
+		boxAttrs,
+		labelAttrs,
+		boxLayer,
+		labelLayer,
+		boxRenderer = null,
+	}) {
+		if(!text) {
+			return {width: 0, height: 0, label: null, box: null};
+		}
+
+		let shift = 0;
+		let anchorX = x;
+		switch(labelAttrs['text-anchor']) {
+		case 'middle':
+			shift = 0.5;
+			anchorX += (padding.left - padding.right) / 2;
+			break;
+		case 'end':
+			shift = 1;
+			anchorX -= padding.right;
+			break;
+		default:
+			shift = 0;
+			anchorX += padding.left;
+			break;
+		}
+
+		const label = new SVGTextBlock(labelLayer, labelAttrs, {
+			text,
+			x: anchorX,
+			y: y + padding.top,
+		});
+
+		const width = (label.width + padding.left + padding.right);
+		const height = (label.height + padding.top + padding.bottom);
+
+		let box = null;
+		if(boxRenderer) {
+			box = boxRenderer({
+				'x': anchorX - label.width * shift - padding.left,
+				'y': y,
+				'width': width,
+				'height': height,
+			});
+		} else {
+			box = renderBox(boxAttrs, {
+				'x': anchorX - label.width * shift - padding.left,
+				'y': y,
+				'width': width,
+				'height': height,
+			});
+		}
+
+		if(boxLayer === labelLayer) {
+			boxLayer.insertBefore(box, label.firstLine());
+		} else {
+			boxLayer.appendChild(box);
+		}
+
+		return {width, height, label, box};
+	}
+
+	return {
+		renderBox,
+		renderNote,
+		renderBoxedText,
+	};
+});

scripts/sequence/SVGShapes_spec.js

@@ -0,0 +1,107 @@
+defineDescribe('SVGShapes', ['./SVGShapes'], (SVGShapes) => {
+	'use strict';
+
+	describe('renderBox', () => {
+		it('returns a simple rect SVG element', () => {
+			const node = SVGShapes.renderBox({
+				'foo': 'bar',
+			}, {
+				'x': 10,
+				'y': 20,
+				'width': 30,
+				'height': 40,
+			});
+			expect(node.tagName).toEqual('rect');
+			expect(node.getAttribute('foo')).toEqual('bar');
+			expect(node.getAttribute('x')).toEqual('10');
+			expect(node.getAttribute('y')).toEqual('20');
+			expect(node.getAttribute('width')).toEqual('30');
+			expect(node.getAttribute('height')).toEqual('40');
+		});
+	});
+
+	describe('renderNote', () => {
+		it('returns a group containing a rectangle with a page flick', () => {
+			const node = SVGShapes.renderNote({
+				'foo': 'bar',
+			}, {
+				'zig': 'zag',
+			}, {
+				'x': 10,
+				'y': 20,
+				'width': 30,
+				'height': 40,
+			});
+			expect(node.tagName).toEqual('g');
+			expect(node.children.length).toEqual(2);
+			const back = node.children[0];
+			expect(back.getAttribute('foo')).toEqual('bar');
+			expect(back.getAttribute('points')).toEqual(
+				'10 20 ' +
+				'33 20 ' +
+				'40 27 ' +
+				'40 60 ' +
+				'10 60'
+			);
+			const flick = node.children[1];
+			expect(flick.getAttribute('zig')).toEqual('zag');
+			expect(flick.getAttribute('points')).toEqual(
+				'33 20 ' +
+				'33 27 ' +
+				'40 27'
+			);
+		});
+	});
+
+	describe('renderBoxedText', () => {
+		it('renders a label', () => {
+			const o = document.createElement('p');
+			const rendered = SVGShapes.renderBoxedText('foo', {
+				x: 1,
+				y: 2,
+				padding: {left: 4, top: 8, right: 16, bottom: 32},
+				boxAttrs: {},
+				labelAttrs: {'font-size': 10, 'line-height': 1.5, 'foo': 'bar'},
+				boxLayer: o,
+				labelLayer: o,
+			});
+			expect(rendered.label.text).toEqual('foo');
+			expect(rendered.label.x).toEqual(5);
+			expect(rendered.label.y).toEqual(10);
+			expect(rendered.label.firstLine().parentNode).toEqual(o);
+		});
+
+		it('positions a box beneath the rendered label', () => {
+			const o = document.createElement('p');
+			const rendered = SVGShapes.renderBoxedText('foo', {
+				x: 1,
+				y: 2,
+				padding: {left: 4, top: 8, right: 16, bottom: 32},
+				boxAttrs: {'foo': 'bar'},
+				labelAttrs: {'font-size': 10, 'line-height': 1.5},
+				boxLayer: o,
+				labelLayer: o,
+			});
+			expect(rendered.box.getAttribute('x')).toEqual('1');
+			expect(rendered.box.getAttribute('y')).toEqual('2');
+			expect(rendered.box.getAttribute('height')).toEqual('55');
+			expect(rendered.box.getAttribute('foo')).toEqual('bar');
+			expect(rendered.box.parentNode).toEqual(o);
+		});
+
+		it('returns the size of the rendered box', () => {
+			const o = document.createElement('p');
+			const rendered = SVGShapes.renderBoxedText('foo', {
+				x: 1,
+				y: 2,
+				padding: {left: 4, top: 8, right: 16, bottom: 32},
+				boxAttrs: {},
+				labelAttrs: {'font-size': 10, 'line-height': 1.5},
+				boxLayer: o,
+				labelLayer: o,
+			});
+			expect(rendered.width).toBeGreaterThan(20 - 1);
+			expect(rendered.height).toEqual(55);
+		});
+	});
+});

scripts/sequence/SVGTextBlock.js

@@ -1,16 +1,23 @@
 define(['./SVGUtilities'], (svg) => {
 	'use strict';
 
-	return class SVGTextBlock {
+	function fontDetails(attrs) {
+		const size = Number(attrs['font-size']);
+		const lineHeight = size * (Number(attrs['line-height']) || 1);
+		return {
+			size,
+			lineHeight,
+		};
+	}
+
+	class SVGTextBlock {
 		constructor(
 			container,
 			attrs,
-			lineHeight,
 			{text = '', x = 0, y = 0} = {}
 		) {
 			this.container = container;
 			this.attrs = attrs;
-			this.lineHeight = lineHeight;
 			this.text = '';
 			this.x = x;
 			this.y = y;
@@ -21,12 +28,11 @@ define(['./SVGUtilities'], (svg) => {
 		}
 
 		_updateY() {
-			const sz = Number(this.attrs['font-size']);
+			const {size, lineHeight} = fontDetails(this.attrs);
-			const space = sz * this.lineHeight;
 			this.nodes.forEach(({element}, i) => {
-				element.setAttribute('y', this.y + i * space + sz);
+				element.setAttribute('y', this.y + i * lineHeight + size);
 			});
-			this.height = space * this.nodes.length;
+			this.height = lineHeight * this.nodes.length;
 		}
 
 		_rebuildNodes(count) {
@@ -51,6 +57,14 @@ define(['./SVGUtilities'], (svg) => {
 			this._updateY();
 		}
 
+		firstLine() {
+			if(this.nodes.length > 0) {
+				return this.nodes[0].element;
+			} else {
+				return null;
+			}
+		}
+
 		setText(newText) {
 			if(newText === this.text) {
 				return;
@@ -93,5 +107,69 @@ define(['./SVGUtilities'], (svg) => {
 			this.width = 0;
 			this.height = 0;
 		}
+	}
+
+	class SizeTester {
+		constructor(container) {
+			this.testers = svg.make('g', {'display': 'none'});
+			this.container = container;
+			this.cache = new Map();
+		}
+
+		measure(attrs, content) {
+			if(!content) {
+				return {width: 0, height: 0};
+			}
+
+			let tester = this.cache.get(attrs);
+			if(!tester) {
+				const text = svg.makeText();
+				const node = svg.make('text', attrs);
+				node.appendChild(text);
+				this.testers.appendChild(node);
+				tester = {text, node};
+				this.cache.set(attrs, tester);
+			}
+
+			if(!this.testers.parentNode) {
+				this.container.appendChild(this.testers);
+			}
+
+			const lines = content.split('\n');
+			let width = 0;
+			lines.forEach((line) => {
+				tester.text.nodeValue = line;
+				width = Math.max(width, tester.node.getComputedTextLength());
+			});
+
+			return {
+				width,
+				height: lines.length * fontDetails(attrs).lineHeight,
 			};
+		}
+
+		measureHeight(attrs, content) {
+			if(!content) {
+				return 0;
+			}
+
+			const lines = content.split('\n');
+			return lines.length * fontDetails(attrs).lineHeight;
+		}
+
+		resetCache() {
+			svg.empty(this.testers);
+			this.cache.clear();
+		}
+
+		detach() {
+			if(this.testers.parentNode) {
+				this.container.removeChild(this.testers);
+			}
+		}
+	}
+
+	SVGTextBlock.SizeTester = SizeTester;
+
+	return SVGTextBlock;
 });

scripts/sequence/SVGTextBlock_spec.js

@@ -1,14 +1,20 @@
-defineDescribe('SVGTextBlock', ['./SVGTextBlock'], (SVGTextBlock) => {
+defineDescribe('SVGTextBlock', [
+	'./SVGTextBlock',
+	'./SVGUtilities',
+], (
+	SVGTextBlock,
+	svg
+) => {
 	'use strict';
 
-	const attrs = {'font-size': 10};
+	const attrs = {'font-size': 10, 'line-height': 1.5};
 	let hold = null;
 	let block = null;
 
 	beforeEach(() => {
-		hold = document.createElement('p');
+		hold = svg.makeContainer();
 		document.body.appendChild(hold);
-		block = new SVGTextBlock(hold, attrs, 1.5);
+		block = new SVGTextBlock(hold, attrs);
 	});
 
 	afterEach(() => {
@@ -24,19 +30,19 @@ defineDescribe('SVGTextBlock', ['./SVGTextBlock'], (SVGTextBlock) => {
 		});
 
 		it('adds the given text if specified', () => {
-			block = new SVGTextBlock(hold, attrs, 1.5, {text: 'abc'});
+			block = new SVGTextBlock(hold, attrs, {text: 'abc'});
 			expect(block.text).toEqual('abc');
 			expect(hold.children.length).toEqual(1);
 		});
 
 		it('uses the given coordinates if specified', () => {
-			block = new SVGTextBlock(hold, attrs, 1.5, {x: 5, y: 7});
+			block = new SVGTextBlock(hold, attrs, {x: 5, y: 7});
 			expect(block.x).toEqual(5);
 			expect(block.y).toEqual(7);
 		});
 	});
 
-	describe('setText', () => {
+	describe('.setText', () => {
 		it('sets the text to the given content', () => {
 			block.setText('foo');
 			expect(block.text).toEqual('foo');
@@ -51,6 +57,12 @@ defineDescribe('SVGTextBlock', ['./SVGTextBlock'], (SVGTextBlock) => {
 			expect(hold.children[1].innerHTML).toEqual('bar');
 		});
 
+		it('populates width and height with the size of the text', () => {
+			block.setText('foo\nbar');
+			expect(block.width).toBeGreaterThan(0);
+			expect(block.height).toEqual(30);
+		});
+
 		it('re-uses text nodes when possible, adding more if needed', () => {
 			block.setText('foo\nbar');
 			const line0 = hold.children[0];
@@ -89,7 +101,7 @@ defineDescribe('SVGTextBlock', ['./SVGTextBlock'], (SVGTextBlock) => {
 		});
 	});
 
-	describe('reanchor', () => {
+	describe('.reanchor', () => {
 		it('moves all nodes', () => {
 			block.setText('foo\nbaz');
 			block.reanchor(5, 7);
@@ -100,7 +112,7 @@ defineDescribe('SVGTextBlock', ['./SVGTextBlock'], (SVGTextBlock) => {
 		});
 	});
 
-	describe('clear', () => {
+	describe('.clear', () => {
 		it('resets the text empty', () => {
 			block.setText('foo\nbaz');
 			block.setText('');
@@ -110,4 +122,80 @@ defineDescribe('SVGTextBlock', ['./SVGTextBlock'], (SVGTextBlock) => {
 			expect(block.height).toEqual(0);
 		});
 	});
+
+	describe('SizeTester', () => {
+		let tester = null;
+
+		beforeEach(() => {
+			tester = new SVGTextBlock.SizeTester(hold);
+		});
+
+		describe('.measure', () => {
+			it('calculates the size of the rendered text', () => {
+				const size = tester.measure(attrs, 'foo');
+				expect(size.width).toBeGreaterThan(0);
+				expect(size.height).toEqual(15);
+			});
+
+			it('measures multiline text', () => {
+				const size = tester.measure(attrs, 'foo\nbar');
+				expect(size.width).toBeGreaterThan(0);
+				expect(size.height).toEqual(30);
+			});
+
+			it('returns 0, 0 for empty content', () => {
+				const size = tester.measure(attrs, '');
+				expect(size.width).toEqual(0);
+				expect(size.height).toEqual(0);
+			});
+
+			it('returns the maximum width for multiline text', () => {
+				const size0 = tester.measure(attrs, 'foo');
+				const size1 = tester.measure(attrs, 'longline');
+				const size = tester.measure(attrs, 'foo\nlongline\nfoo');
+				expect(size1.width).toBeGreaterThan(size0.width);
+				expect(size.width).toEqual(size1.width);
+			});
+		});
+
+		describe('.measureHeight', () => {
+			it('calculates the height of the rendered text', () => {
+				const height = tester.measureHeight(attrs, 'foo');
+				expect(height).toEqual(15);
+			});
+
+			it('measures multiline text', () => {
+				const height = tester.measureHeight(attrs, 'foo\nbar');
+				expect(height).toEqual(30);
+			});
+
+			it('returns 0 for empty content', () => {
+				const height = tester.measureHeight(attrs, '');
+				expect(height).toEqual(0);
+			});
+
+			it('does not require the container', () => {
+				tester.measureHeight(attrs, 'foo');
+				expect(hold.children.length).toEqual(0);
+			});
+		});
+
+		describe('.detach', () => {
+			it('removes the test node from the DOM', () => {
+				tester.measure(attrs, 'foo');
+				expect(hold.children.length).toEqual(1);
+				tester.detach();
+				expect(hold.children.length).toEqual(0);
+			});
+
+			it('does not prevent using the tester again later', () => {
+				tester.measure(attrs, 'foo');
+				tester.detach();
+
+				const size = tester.measure(attrs, 'foo');
+				expect(hold.children.length).toEqual(1);
+				expect(size.width).toBeGreaterThan(0);
+			});
+		});
+	});
 });

scripts/specs.js

@@ -6,4 +6,5 @@ define([
 	'sequence/ArrayUtilities_spec',
 	'sequence/SVGUtilities_spec',
 	'sequence/SVGTextBlock_spec',
+	'sequence/SVGShapes_spec',
 ]);