From b45d2e5021f9e8a21823be58747271fe2b74edde Mon Sep 17 00:00:00 2001
From: 13766800364 <13766800364@qq.com>
Date: Thu, 9 Oct 2025 16:10:38 +0800
Subject: [PATCH] Add File

---
 .../drinkjava2/frog/objects/SeeSaw.java       | 93 +++++++++++++++++++
 1 file changed, 93 insertions(+)
 create mode 100644 history/003a_legs/src/main/java/com/github/drinkjava2/frog/objects/SeeSaw.java

diff --git a/history/003a_legs/src/main/java/com/github/drinkjava2/frog/objects/SeeSaw.java b/history/003a_legs/src/main/java/com/github/drinkjava2/frog/objects/SeeSaw.java
new file mode 100644
index 0000000..5f220ae
--- /dev/null
+++ b/history/003a_legs/src/main/java/com/github/drinkjava2/frog/objects/SeeSaw.java
@@ -0,0 +1,93 @@
+/* Copyright 2018-2020 the original author or authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License"); you may not
+ * use this file except in compliance with the License. You may obtain a copy of
+ * the License at http://www.apache.org/licenses/LICENSE-2.0 Unless required by
+ * applicable law or agreed to in writing, software distributed under the
+ * License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS
+ * OF ANY KIND, either express or implied. See the License for the specific
+ * language governing permissions and limitations under the License.
+ */
+package com.github.drinkjava2.frog.objects;
+
+import static com.github.drinkjava2.frog.Env.ENV_HEIGHT;
+import static com.github.drinkjava2.frog.Env.ENV_WIDTH;
+import static com.github.drinkjava2.frog.Env.bricks;
+
+import com.github.drinkjava2.frog.Env;
+import com.github.drinkjava2.frog.Frog;
+import com.github.drinkjava2.frog.util.RandomUtils;
+
+/**
+ * This is a seesaw to train frog's balance
+ * 
+ * @author Yong Zhu
+ * @since 2.0.1
+ */
+public class SeeSaw implements Object {
+	private static final int LEGNTH = 300;
+	private static final int CENTER_X = Env.ENV_WIDTH / 2;
+	private static final int CENTER_Y = Env.ENV_HEIGHT / 2;
+
+	private double angle = 0;// -PI/4 to PI/4
+	private double leftWeight = 0;
+	private double rightWeight = 0;
+
+	@Override
+	public void build() {
+		angle = 0;
+	}
+
+	@Override
+	public void destory() {
+
+	}
+
+	@Override
+	public void active(int screen) {
+		for (int i = 0; i < ENV_WIDTH; i++) {// 清除食物
+			for (int j = 0; j < ENV_HEIGHT; j++)
+				if (bricks[i][j] == Material.SEESAW)
+					bricks[i][j] = 0;
+		}
+
+		if (RandomUtils.percent(2))
+			leftWeight = RandomUtils.nextFloat() * 3;
+		if (RandomUtils.percent(2))
+			rightWeight = RandomUtils.nextFloat() * 3;
+		Frog f = Env.frogs.get(screen);
+
+		if (f.x < (CENTER_X - LEGNTH / 2) || f.x > (CENTER_X + LEGNTH / 2))
+			f.energy -= 100000; // 如果走出跷跷板外则扣分，出局
+		double left = leftWeight - (f.x - CENTER_X);
+		double right = rightWeight + (f.x - CENTER_X);
+		// right - left need in -100 to +100
+		angle = angle + (right - left) * Math.PI * .000001;
+		if (angle > Math.PI / 6) {
+			angle = Math.PI / 6;
+			f.energy -= 200;
+		}
+		if (angle < -Math.PI / 6) {
+			angle = -Math.PI / 6;
+			f.energy -= 200;
+		}
+		f.y = CENTER_Y + (int) Math.round((f.x - CENTER_X) * Math.tan(angle));
+		f.energy -= Math.abs(angle) * 180; // 角度越大，扣分越多
+		int x;
+		int y;
+		for (int l = -LEGNTH / 2; l <= LEGNTH / 2; l++) {
+			x = (int) Math.round(l * Math.cos(angle));
+			y = (int) Math.round(l * Math.sin(angle));
+			Env.bricks[CENTER_X + x][CENTER_Y + y] = Material.SEESAW;
+		}
+
+		// 画底座
+		for (int i = 1; i < 10; i++) {
+			Env.bricks[CENTER_X - i][CENTER_Y + i] = Material.SEESAW_BASE;
+			Env.bricks[CENTER_X + i][CENTER_Y + i] = Material.SEESAW_BASE;
+		}
+		for (int i = -10; i < 10; i++)
+			Env.bricks[CENTER_X + i][CENTER_Y + 10] = Material.SEESAW_BASE;
+
+	}
+}