docs later

mods/onTryMoveInto.js

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+elements.on_try_move_into_test = {
+	color: "#ffffff",
+	properties: {
+		ticks: 0,
+		attemptedMovesIntoPixel: 0,
+	},	
+	behavior: behaviors.POWDER,
+	reactions: {
+		"dirt": { elem1: "diamond" },
+	},
+	state: "solid",
+	category: "special",
+	density: 1000,
+	tick: function(pixel) {
+		pixel.ticks++;
+	},
+	onTryMoveInto: function(pixel,otherPixel) {
+		pixel.attemptedMovesIntoPixel++;
+		var otherElement = otherPixel.element;
+		if(otherElement === "ash") {
+		console.log(`This is a test of potentially undesired multiplicate running. (tick: ${pixelTicks}, move attempts: ${pixel.attemptedMovesIntoPixel})`);
+			//if(deletePixel(pixel.x,pixel.y)) {
+			//	console.log("This pixel has been deleted.");
+			//};
+		};
+	},
+	desc: "Try burying this pixel and see what happens. (Use Debug)\n\nonTryMoveInto is run as part of tryMove, <em>before reactions</em>, while tick functions are run as part of pixelDraw.\n<span style='color:red;'>In some circumstances, such as a pixel being buried under a pile of anything that isn't a sturdy powder, this function may run multiple times per tick.</span> For example, bury this pixel in ash and look in the console.\n\nTo use this function, include in your element definition the \"onTryMoveInto\" key with a function value, similarly to tick functions. This function takes two arguments; \"otherPixel\" is the pixel that is trying to move and \"pixel\" is the pixel whose position otherPixel is trying to move into.",
+	related: ["debug", "ash"],
+}
+
+function tryMove(pixel,nx,ny,leaveBehind=undefined) {
+	var info = elements[pixel.element];
+	var oob = outOfBounds(nx,ny);
+	if (isEmpty(nx,ny,false,oob)) { // If coords is empty, move to coords
+		movePixel(pixel,nx,ny,leaveBehind);
+		return true;
+	}
+	else if (!oob) {
+		// Reactions
+		newPixel = pixelMap[nx][ny];
+		var newInfo = elements[newPixel.element];
+		if(newInfo.onTryMoveInto !== undefined) {
+			newInfo.onTryMoveInto(newPixel,pixel);
+		}
+		var rr1 = false;
+		if (info.reactions !== undefined && info.reactions[newPixel.element] !== undefined) {
+			rr1 = reactPixels(pixel,newPixel)
+			if (rr1) {
+				return true;
+			}
+		}
+		if (!rr1 && elements[newPixel.element].reactions !== undefined && elements[newPixel.element].reactions[pixel.element] !== undefined && !elements[newPixel.element].reactions[pixel.element].oneway) {
+			if (reactPixels(newPixel,pixel)) {
+				return true;
+			}
+		}
+		// Density
+		if (elements[pixel.element].id !== elements[newPixel.element].id) {
+			if (info.density !== undefined && elements[newPixel.element].density !== undefined) {
+				// if the pixel's state + ">" + newPixel's state is in validDensitySwaps, and the pixel's density is larger than the newPixel's density, swap the pixels
+				if (validDensitySwaps[info.state][elements[newPixel.element].state] && info.density >= elements[newPixel.element].density) {
+					// chance depending on the difference in density
+					if (Math.random() < (info.density - elements[newPixel.element].density)/(info.density + elements[newPixel.element].density)) {
+						swapPixels(pixel,newPixel);
+						return true;
+					}
+				}
+			}
+		}
+	}
+	return false;
+}