'now' and 'lastNow' as draw parameters

src/sketch.js

@@ -58,6 +58,9 @@ export default class Sketch {
 		this.canvas.width = this.container.offsetWidth;
 		this.canvas.height = this.container.offsetHeight;
 
+		this.context.lastUTC = this.context.utc || null;
+		this.context.utc = Date.now();
+
 		this.context.now = now;
 		this.context.lastNow = this.lastNow;
 

src/tessellate.js

@@ -223,6 +223,9 @@ export class Tessellate {
 			height, width,
 			scale: this.cartographer.getScale(),
 
+			lastNow: context.lastUTC,
+			now: context.utc,
+
 			tilePoints: this.getTilePoints({
 				upperLeftX: 0,
 				upperLeftY: 0,