从本质上讲,我只需要一些有关如何使圆从活动对象反弹的指导.我遇到了麻烦,已经尝试了三个小时,因此向论坛寻求帮助.我尝试了多个“ if”语句,但显然我无法正确理解,因为没有一个起作用.谢谢 ：)

我已经尝试了3个小时,用不同的if语句弄清楚了这一点.

float x;

float easing = 1;

float circle_x = 1;

float circle_y = 30;

float rad = 12.5;

float gravity = 0.98;

float move_x = 5;

float move_y = 5;

void setup() {

size(640, 480);

frameRate(60);

}

void draw() {

background(#87CEEB);

fill(#7cfc00);

rect(0, 430, 640, 80);

float targetX = mouseX;

float dx = targetX - x;

x += dx * easing;

fill(#000000);

rect(x, 400, 30, 30);

rect(x-20, 390, 70, 10);

rect(x, 430, 5, 20);

rect(x+25, 430, 5, 20);

ellipse(circle_x, circle_y, 25, 25);

circle_x = circle_x + move_x;

circle_y = circle_y + move_y;

if (circle_x > width) {

circle_x = width;

move_x = -move_x;

}

if (circle_y > height) {

circle_y = height;

move_y = -move_y;

}

if (circle_x < 0) {

circle_x = 0;

move_x = -move_x;

}

if (circle_y < 0) {

circle_y = 0;

move_y= -move_y;

}

}

将任何变量插入到if语句中,然后只接收回来：我的鼠标光标(不是对象)将球反弹,毛刺的圆圈和模糊的图像.

解决方法:

必须检查球的x坐标是否在对象的范围内(objW是对象的宽度)：

circle_x > x && circle_x < x + objW

并且如果球的y坐标已达到对象的高度(objH是对象的高度,而circleR是球的半径)：

circle_y > objH - circleR

此外,重要的是要先进行命中测试,然后在物体反弹后再进行测试.一个好的样式是在else if语句中执行此操作：

int objX1 = -20;

int objX2 = 70;

int objH = 390;

int circleR = 25/2;

if (circle_x > x + objX1 && circle_x < x + objX2 && circle_y > objH - circleR ) {

circle_y = objH-circleR;

move_y = -move_y;

}

else if (circle_y > height) {

circle_y = height;

move_y = -move_y;

}

else if (circle_y < 0) {

circle_y = 0;

move_y= -move_y;

}

此外,我建议先计算球的位置,然后在当前位置绘制球：

float x;

float easing = 1;

float circle_x = 1;

float circle_y = 30;

float rad = 12.5;

float gravity = 0.98;

float move_x = 5;

float move_y = 5;

void setup() {

size(640, 480);

frameRate(60);

}

void draw() {

background(#87CEEB);

fill(#7cfc00);

rect(0, 430, 640, 80);

float targetX = mouseX;

float dx = targetX - x;

x += dx * easing;

circle_x = circle_x + move_x;

circle_y = circle_y + move_y;

if (circle_x > width) {

circle_x = width;

move_x = -move_x;

}

else if (circle_x < 0) {

circle_x = 0;

move_x = -move_x;

}

int objW = 70;

int objH = 390;

int circleR = 25/2;

if (circle_x > x && circle_x < x + objW && circle_y > objH-circleR ) {

circle_y = objH-circleR;

move_y = -move_y;

}

else if (circle_y > height) {

circle_y = height;

move_y = -move_y;

}

else if (circle_y < 0) {

circle_y = 0;

move_y= -move_y;

}

fill(#000000);

rect(x, 400, 30, 30);

rect(x-20, 390, 70, 10);

rect(x, 430, 5, 20);

rect(x+25, 430, 5, 20);

ellipse(circle_x, circle_y, 25, 25);

}

标签：bounce,java,object,processing

来源： https://codeday.me/bug/20191210/2105256.html