Upit | Learn about creating the game Speedway Sprint with gen AI

/**** * Plugins ****/ var tween = LK.import("@upit/tween.v1"); var storage = LK.import("@upit/storage.v1", { level: 1, bestTime: 0 }); /**** * Classes ****/ var Car = Container.expand(function () { var self = Container.call(this); var carGraphics = self.attachAsset('playerCar', { anchorX: 0.5, anchorY: 0.5 }); self.speed = 5; self.update = function () { // Player car does not move forward automatically anymore // Only horizontal movement is allowed, so no change to self.y here if (self.x < 0) { self.x = 2048; } else if (self.x > 2048) { self.x = 0; } }; return self; }); var EnemyCar = Container.expand(function () { var self = Container.call(this); var enemyCarGraphics = self.attachAsset('enemyCar', { anchorX: 0.5, anchorY: 0.5 }); self.speed = 5; self.update = function () { // Enemy cars move down the screen (already correct) self.y += self.speed; if (self.x < 0) { self.x = 2048; } else if (self.x > 2048) { self.x = 0; } }; return self; }); /**** * Initialize Game ****/ var game = new LK.Game({ backgroundColor: 0x000000 }); /**** * Game Code ****/ var road = LK.getAsset('road', { anchorX: 0.5, anchorY: 0.5, x: 1024, y: 1366 }); game.addChild(road); var playerCar = game.addChild(new Car()); // Place player in left or right lane randomly, not center playerCar.x = Math.random() > 0.5 ? 512 : 1536; // 512 = left lane, 1536 = right lane playerCar.y = 2300; // Start near the bottom, adjusted for bigger car var enemyCars = []; function spawnEnemyCar() { // Only allow enemy cars to spawn in the same vertical lines as the player (left or right lane) // Lane Xs: left, right var laneXs = [512, 1536]; // Car height for vertical gap var carHeight = 660; var verticalGapMultiplier = 2.2; // Find the highest Y of any existing enemy car, or use -330 if none var topY = -330; for (var i = 0; i < enemyCars.length; i++) { if (enemyCars[i].y < topY) { topY = enemyCars[i].y; } } // Patterns: only left, only right, or both, always aligned with player lanes var patterns = [ // Only left lane [{ x: laneXs[0] }], // Only right lane [{ x: laneXs[1] }], // Both lanes, vertical stack [{ x: laneXs[0] }, { x: laneXs[1] }], // Alternating left-right [{ x: laneXs[0] }, { x: laneXs[1] }, { x: laneXs[0] }], // Alternating right-left [{ x: laneXs[1] }, { x: laneXs[0] }, { x: laneXs[1] }]]; // Keep track of which pattern to use next if (typeof spawnEnemyCar.patternIndex === "undefined") { spawnEnemyCar.patternIndex = 0; } // Shuffle patterns order every cycle for variety if (typeof spawnEnemyCar.patternOrder === "undefined" || spawnEnemyCar.patternOrder.length === 0) { var order = []; for (var i = 0; i < patterns.length; i++) order.push(i); // Fisher-Yates shuffle for (var i = order.length - 1; i > 0; i--) { var j = Math.floor(Math.random() * (i + 1)); var temp = order[i]; order[i] = order[j]; order[j] = temp; } spawnEnemyCar.patternOrder = order; spawnEnemyCar.patternIndex = 0; } var patternIdx = spawnEnemyCar.patternOrder[spawnEnemyCar.patternIndex]; var pattern = patterns[patternIdx]; spawnEnemyCar.patternIndex++; if (spawnEnemyCar.patternIndex >= spawnEnemyCar.patternOrder.length) { spawnEnemyCar.patternOrder = []; } // Place new pattern below the last one, with the specified gap var spawnY = topY; for (var i = 0; i < pattern.length; i++) { var carDef = pattern[i]; var enemyCar = new EnemyCar(); enemyCar.x = carDef.x; enemyCar.y = spawnY; enemyCars.push(enemyCar); game.addChild(enemyCar); spawnY -= carHeight * verticalGapMultiplier; } } game.update = function () { // No gradual movement needed; handled instantly in game.down // Only update playerCar for horizontal movement, not forward movement playerCar.update(); for (var i = enemyCars.length - 1; i >= 0; i--) { var enemyCar = enemyCars[i]; enemyCar.update(); if (enemyCar.y > 2832) { // If the enemy car goes off the screen enemyCar.destroy(); enemyCars.splice(i, 1); } if (playerCar.intersects(enemyCar)) { LK.showGameOver(); } } if (LK.ticks % 120 == 0) { // Spawn new enemy cars every 2 seconds to keep more space between them spawnEnemyCar(); } }; var inputState = { leftPressed: false, rightPressed: false }; game.down = function (x, y, obj) { if (x < 1024) { inputState.leftPressed = true; playerCar.x = 512; // Instantly move to left lane inputState.rightPressed = false; } else { inputState.rightPressed = true; playerCar.x = 1536; // Instantly move to right lane inputState.leftPressed = false; } }; game.up = function (x, y, obj) { inputState.leftPressed = false; inputState.rightPressed = false; };

===================================================================
--- original.js
+++ change.js
@@ -69,11 +69,11 @@
 playerCar.x = Math.random() > 0.5 ? 512 : 1536; // 512 = left lane, 1536 = right lane
 playerCar.y = 2300; // Start near the bottom, adjusted for bigger car
 var enemyCars = [];
 function spawnEnemyCar() {
-	// Custom spawn logic: some cars go out of the road, some go in the middle, cars only go from left/right, all vertically aligned with player
-	// Lane Xs: left out, left, center, right, right out
-	var laneXs = [64, 512, 1024, 1536, 1984];
+	// Only allow enemy cars to spawn in the same vertical lines as the player (left or right lane)
+	// Lane Xs: left, right
+	var laneXs = [512, 1536];
 	// Car height for vertical gap
 	var carHeight = 660;
 	var verticalGapMultiplier = 2.2;
 	// Find the highest Y of any existing enemy car, or use -330 if none
@@ -82,96 +82,40 @@
 		if (enemyCars[i].y < topY) {
 			topY = enemyCars[i].y;
 		}
 	}
-	// Patterns: each is a vertical stack, only left/right/center, some out of road, always vertical alignment
+	// Patterns: only left, only right, or both, always aligned with player lanes
 	var patterns = [
-	// Only left and right, vertical stack, some out of road
+	// Only left lane
 	[{
 		x: laneXs[0]
-	},
-	// out of road left
-	{
-		x: laneXs[1]
-	},
-	// left
-	{
-		x: laneXs[3]
-	},
-	// right
-	{
-		x: laneXs[4]
-	} // out of road right
-	],
-	// Center and right, vertical stack
+	}],
+	// Only right lane
 	[{
-		x: laneXs[2]
-	},
-	// center
-	{
-		x: laneXs[3]
-	},
-	// right
-	{
-		x: laneXs[4]
-	} // out of road right
-	],
-	// Left, center, right, vertical stack
-	[{
 		x: laneXs[1]
-	},
-	// left
-	{
-		x: laneXs[2]
-	},
-	// center
-	{
-		x: laneXs[3]
-	} // right
-	],
-	// Only out of road, vertical stack
+	}],
+	// Both lanes, vertical stack
 	[{
 		x: laneXs[0]
-	},
-	// out of road left
-	{
-		x: laneXs[4]
-	} // out of road right
-	],
-	// Left, right, left, right, vertical stack
+	}, {
+		x: laneXs[1]
+	}],
+	// Alternating left-right
 	[{
+		x: laneXs[0]
+	}, {
 		x: laneXs[1]
-	},
-	// left
-	{
-		x: laneXs[3]
-	},
-	// right
-	{
-		x: laneXs[1]
-	},
-	// left
-	{
-		x: laneXs[3]
-	} // right
-	],
-	// Center, left, right, out of road right
+	}, {
+		x: laneXs[0]
+	}],
+	// Alternating right-left
 	[{
-		x: laneXs[2]
-	},
-	// center
-	{
 		x: laneXs[1]
-	},
-	// left
-	{
-		x: laneXs[3]
-	},
-	// right
-	{
-		x: laneXs[4]
-	} // out of road right
-	]];
+	}, {
+		x: laneXs[0]
+	}, {
+		x: laneXs[1]
+	}]];
 	// Keep track of which pattern to use next
 	if (typeof spawnEnemyCar.patternIndex === "undefined") {
 		spawnEnemyCar.patternIndex = 0;
 	}

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