Creating a Simple Enemy AI

Programming Questions

wilcapriv

in Programming Questions • 11 months ago

Hi guys I been working on creating a simple enemy AI for my space invader type game and running into several small issues, one is that I had to redo my functions over and over again to create different positions for the enemies and have them travel at different speed was wondering if there was a way I could make my functions simpler and second when i actually start putting enemies on screen well they kick each other out of the screen which was pretty funny but not the effect i was going for. Here my code so if anybody could give me a quick hand fairly new at this stuff and a little confuse

float enemyX = 0; // enemies
float enemyY = 0;
float enemyX1 = 0;
float enemyY1 = 20;
float enemyX2 = 0;
float enemyY2 = 0;
float enemyX3 = 0;
float enemyY3 = 0;
float enemyX4 = 0;
float enemyY4 = 0;

float enemyX5 = 0;
float enemyY5 = 0;
float enemyX6 = 0;
float enemyY6 = 0;
float enemyX7 = 0;
float enemyY7 = 0;
float enemyX8 = 0;
float enemyY8 = 0;
float enemyX9 = 0;
float enemyY9 = 0;
float enemyX10 = 0;
float enemyY10 = 0;
float enemyX11 = 0;
float enemyY11 = 0;
float enemyX12 = 0;
float enemyY12 = 0;
float enemyX13 = 0;
float enemyY13 = 0;
float enemyX14 = 0;
float enemyY14 = 0;
float enemyX15 = 0;
float enemyY15 = 0;
float enemyX16 = 0;
float enemyY16 = 0;
float enemyX17 = 0;
float enemyY18 = 0;
float enemyX19 = 0;
float enemyY19 = 0;
float enemyX20 = 0;
float enemyY20 = 0;
float enemyX21 = 0;
float enemyY21 = 0;
float enemyX22 = 0;
float enemyY22 = 0;
float enemyX23 = 0;
float enemyY23 = 0;
float speed = 10;
float speed1 = 1; // enemies speed
float speed2 = 20;
float speed3 = 30;
float speed4 = 40;
float speed5 = 50;
//Global variables listed above

void setup(){ //basic setup for enemy 3 test
size(500,500); //skect size
smooth(); //does something i forgot
}

void draw(){ //our main program
background(0);
move(); // to move enemies
bounce(); // to make enemies move from left to right
drawEnemy(30,50,50,color(255,0 ,0));
move1(); // to move enemies
bounce1(); // to make enemies move from left to right
drawEnemy1(60,70,60,color(0,25 5,0));
}

void move(){
// Change the x location by speed
enemyX = enemyX + speed;
}
void move1(){
// Change the x location by speed
enemyX1 = enemyX1 + speed;
}
void move2(){
// Change the x location by speed
enemyX2 = enemyX2 + speed;
}
void move3(){
// Change the x location by speed
enemyX3 = enemyX3 + speed;
}
void move4(){
// Change the x location by speed
enemyX4 = enemyX4 + speed;
}
void move5(){
// Change the x location by speed
enemyX5 = enemyX5 + speed1;
}
void move6(){
// Change the x location by speed
enemyX6 = enemyX6 + speed1;
}
void move7(){
// Change the x location by speed
enemyX7 = enemyX7 + speed1;
}
void move20(){
// Change the x location by speed
enemyX20 = enemyX20 + speed1;
}
void move8(){
// Change the x location by speed
enemyX8 = enemyX8 + speed1;
}
void move9(){
// Change the x location by speed
enemyX9 = enemyX9 + speed5;
}
void move10(){
// Change the x location by speed
enemyX10 = enemyX10 + speed2;
}
void move11(){
// Change the x location by speed
enemyX11 = enemyX11 + speed4;
}
void move12(){
// Change the x location by speed
enemyX12 = enemyX12 + speed2;
}
void move13(){
// Change the x location by speed
enemyX13 = enemyX13 + speed5;
}
void move14(){
// Change the x location by speed
enemyX14 = enemyX14 + speed3;
}
void move15(){
// Change the x location by speed
enemyX15 = enemyX15 + speed3;
}
void move16(){
// Change the x location by speed
enemyX16 = enemyX16 + speed3;
}
void move17(){
// Change the x location by speed
enemyX17 = enemyX17 + speed4;
}
void bounce(){
if ((enemyX > width) || (enemyX < 0)){
speed = speed * -1;
}
}
void bounce1(){
if ((enemyX1 > width) || (enemyX1 < 0)){
speed = speed * -1;
}
}
void bounce2() {
if ((enemyX2 > width) || (enemyX2 < 0)){
speed = speed * -1;
}
}
void bounce3() {
if ((enemyX3 > width) || (enemyX3 < 0)){
speed = speed * -1;
}
}
void bounce4() {
if ((enemyX4 > width) || (enemyX4 < 0)){
speed = speed * -1;
}
}
void bounce5() {
if ((enemyX5 > width) || (enemyX5 < 0)){
speed1 = speed1 * +1;
}
}
void bounce6() {
if ((enemyX6 > width) || (enemyX6 < 0)){
speed1 = speed1 * -1;
}
}
void bounce7() {
if ((enemyX7 > width) || (enemyX7 < 0)){
speed1 = speed1 * +1;
}
}
void bounce8() {
if ((enemyX8 > width) || (enemyX8 < 0)){
speed1 = speed1 * -1;
}
}
void bounce9() {
if ((enemyX9 > width) || (enemyX9 < 0)){
speed5 = speed5 * -1;
}
}
void bounce10() {
if ((enemyX10 > width) || (enemyX10 < 0)){
speed2 = speed2 * -1;
}
}
void bounce11() {
if ((enemyX11 > width) || (enemyX12 < 0)){
speed4 = speed4 * -1;
}
}
void bounce12() {
if ((enemyX12 > width) || (enemyX12 < 0)){
speed2 = speed2 * -1;
}
}
void bounce13() {
if ((enemyX13 > width) || (enemyX13 < 0)){
speed5 = speed5 * -1;
}
}
void bounce14() {
if ((enemyX14 > width) || (enemyX14 < 0)){
speed3 = speed3 * -1;
}
}
void bounce15() {
if ((enemyX15 > width) || (enemyX15 < 0)){
speed3 = speed3 * -1;
}
}
void bounce16() {
if ((enemyX16 > width) || (enemyX16 < 0)){
speed3 = speed3 * -1;
}
}
void bounce17() {
if ((enemyX17 > width) || (enemyX17 < 0)){
speed4 = speed4 * -1;
}
}
void bounce20() {
if ((enemyX20 > width) || (enemyX20 < 0)){
speed1 = speed1 * -1;
}
}
void drawEnemy(int x, int y, int thesize, color c) {
int offset = thesize / 4;
rectMode(CENTER);
ellipseMode(CENTER);
stroke(200);
fill(c);
rect(enemyX,y,thesize,thesize/ 2);
fill(200);
ellipse(enemyX - offset,y - offset,offset,offset/2);
ellipse(enemyX + offset,y - offset,offset,offset/2);
ellipse(enemyX - offset,y + offset,offset,offset/2);
ellipse(enemyX + offset,y + offset,offset,offset/2);
}
void drawEnemy1(int x, int y, int thesize1, color c) {
int offset1 = thesize1 / 4;
rectMode(CENTER);
ellipseMode(CENTER);
stroke(200);
fill(c);
rect(enemyX1,enemyY1,thesize1, thesize1/2);
fill(200);
ellipse(enemyX1 - offset1,enemyY1 - offset1,offset1,offset1/2);
ellipse(enemyX1 + offset1,enemyY1 - offset1,offset1,offset1/2);
ellipse(enemyX1 - offset1,enemyY1 + offset1,offset1,offset1/2);
ellipse(enemyX1 + offset1,enemyY1 + offset1,offset1,offset1/2);
}

Replies(12)

wilcapriv

Re: Creating a Simple Enemy AI

11 months ago

Ok so looking at my code I realize that I was having all the cars share the same speed and that was making them pull each other apart now I split the speed for each car apart but i feel like there a better way of doing it.

float enemyX = 0; // enemies
float enemyY = 0;
float enemyX1 = 0;
float enemyY1 = 20;
float enemyX2 = 0;
float enemyY2 = 30;
float enemyX3 = 0;
float enemyY3 = 50;
float enemyX4 = 0;
float enemyY4 = 60;
float enemyX5 = 0;
float enemyY5 = 70;
float enemyX6 = 0;
float enemyY6 = 93;
float enemyX7 = 0;
float enemyY7 = 140;
float enemyX8 = 0;
float enemyY8 = 200;
float enemyX9 = 0;
float enemyY9 = 0;
float enemyX10 = 0;
float enemyY10 = 0;
float enemyX11 = 0;
float enemyY11 = 0;
float enemyX12 = 0;
float enemyY12 = 0;
float enemyX13 = 0;
float enemyY13 = 0;
float enemyX14 = 0;
float enemyY14 = 0;
float enemyX15 = 0;
float enemyY15 = 0;
float enemyX16 = 0;
float enemyY16 = 0;
float enemyX17 = 0;
float enemyY18 = 0;
float enemyX19 = 0;
float enemyY19 = 0;
float enemyX20 = 0;
float enemyY20 = 0;
float enemyX21 = 0;
float enemyY21 = 0;
float enemyX22 = 0;
float enemyY22 = 0;
float enemyX23 = 0;
float enemyY23 = 0;
float speed = 1;
float speed1 = 2; // enemies speed
float speed2 = 3;
float speed3 = 4;
float speed4 = 5;
float speed5 = 6;
float speed6 = 7;
float speed7 = 8;
float speed8 = 9;
float speed9 = 10;
float speed10 = 18;
float speed11 = 18;
float speed12 = 18;
float speed13 = 18;
float speed14 = 18;
float speed15 = 18;
float speed16 = 18;
float speed17 = 18;
float speed18 = 18;
float speed19 = 18;
float speed20 = 18;
//Global variables listed above

void setup(){ //basic setup for enemy 3 test
size(1000,680); //skect size
smooth(); //does something i forgot
}

void draw(){ //our main program
background(0);
move(); // to move enemies
bounce(); // to make enemies move from left to right
drawEnemy(30,50,10,color(255,0,0));
move1(); // to move enemies
bounce1(); // to make enemies move from left to right
drawEnemy1(60,70,20,color(0,255,0));
move2(); // to move enemies
bounce2(); // to make enemies move from left to right
drawEnemy2(80,150,30,color(0,0,255));
move3(); // to move enemies
bounce3(); // to make enemies move from left to right
drawEnemy3(0,0,20,color(255,255,255));
move4(); // to move enemies
bounce4(); // to make enemies move from left to right
drawEnemy4(30,400,30,color(255,80,30));
move5(); // to move enemies
bounce5(); // to make enemies move from left to right
drawEnemy5(20,110,55,color(255,255,255));
move6(); // to move enemies
bounce6(); // to make enemies move from left to right
drawEnemy6(200,110,70,color(255,255,255));
move7(); // to move enemies
bounce7(); // to make enemies move from left to right
drawEnemy7(200,110,80,color(173,60,200));
move8(); // to move enemies
bounce8(); // to make enemies move from left to right
drawEnemy8(500,110,90,color(100,230,50));
}

void move(){
// Change the x location by speed
enemyX = enemyX + speed;
}
void move1(){
// Change the x location by speed
enemyX1 = enemyX1 + speed1;
}
void move2(){
// Change the x location by speed
enemyX2 = enemyX2 + speed2;
}
void move3(){
// Change the x location by speed
enemyX3 = enemyX3 + speed3;
}
void move4(){
// Change the x location by speed
enemyX4 = enemyX4 + speed4;
}
void move5(){
// Change the x location by speed
enemyX5 = enemyX5 + speed5;
}
void move6(){
// Change the x location by speed
enemyX6 = enemyX6 + speed6;
}
void move7(){
// Change the x location by speed
enemyX7 = enemyX7 + speed7;
}
void move20(){
// Change the x location by speed
enemyX20 = enemyX20 + speed20;
}
void move8(){
// Change the x location by speed
enemyX8 = enemyX8 + speed8;
}
void move9(){
// Change the x location by speed
enemyX9 = enemyX9 + speed9;
}
void move10(){
// Change the x location by speed
enemyX10 = enemyX10 + speed10;
}
void move11(){
// Change the x location by speed
enemyX11 = enemyX11 + speed11;
}
void move12(){
// Change the x location by speed
enemyX12 = enemyX12 + speed12;
}
void move13(){
// Change the x location by speed
enemyX13 = enemyX13 + speed13;
}
void move14(){
// Change the x location by speed
enemyX14 = enemyX14 + speed14;
}
void move15(){
// Change the x location by speed
enemyX15 = enemyX15 + speed15;
}
void move16(){
// Change the x location by speed
enemyX16 = enemyX16 + speed16;
}
void move17(){
// Change the x location by speed
enemyX17 = enemyX17 + speed17;
}
void bounce(){
if ((enemyX > width) || (enemyX < 0)){
speed = speed * -1;
}
}
void bounce1(){
if ((enemyX1 > width) || (enemyX1 < 0)){
speed1 = speed1 * -1;
}
}
void bounce2() {
if ((enemyX2 > width) || (enemyX2 < 0)){
speed2 = speed2 * -1;
}
}
void bounce3() {
if ((enemyX3 > width) || (enemyX3 < 0)){
speed3 = speed3 * -1;
}
}
void bounce4() {
if ((enemyX4 > width) || (enemyX4 < 0)){
speed4 = speed4 * -1;
}
}
void bounce5() {
if ((enemyX5 > width) || (enemyX5 < 0)){
speed5 = speed5 * -1;
}
}
void bounce6() {
if ((enemyX6 > width) || (enemyX6 < 0)){
speed6 = speed6 * -1;
}
}
void bounce7() {
if ((enemyX7 > width) || (enemyX7 < 0)){
speed7 = speed7 * -1;
}
}
void bounce8() {
if ((enemyX8 > width) || (enemyX8 < 0)){
speed8 = speed8 * -1;
}
}
void bounce9() {
if ((enemyX9 > width) || (enemyX9 < 0)){
speed9 = speed9 * -1;
}
}
void bounce10() {
if ((enemyX10 > width) || (enemyX10 < 0)){
speed10 = speed10 * -1;
}
}
void bounce11() {
if ((enemyX11 > width) || (enemyX12 < 0)){
speed11 = speed11 * -1;
}
}
void bounce12() {
if ((enemyX12 > width) || (enemyX12 < 0)){
speed12 = speed12 * -1;
}
}
void bounce13() {
if ((enemyX13 > width) || (enemyX13 < 0)){
speed13 = speed13 * -1;
}
}
void bounce14() {
if ((enemyX14 > width) || (enemyX14 < 0)){
speed14 = speed14 * -1;
}
}
void bounce15() {
if ((enemyX15 > width) || (enemyX15 < 0)){
speed15 = speed15 * -1;
}
}
void bounce16() {
if ((enemyX16 > width) || (enemyX16 < 0)){
speed16 = speed16 * -1;
}
}
void bounce17() {
if ((enemyX17 > width) || (enemyX17 < 0)){
speed17= speed17 * -1;
}
}
void bounce20() {
if ((enemyX20 > width) || (enemyX20 < 0)){
speed20 = speed20 * -1;
}
}
void drawEnemy(int x, int y, int thesize, color c) {
int offset = thesize / 4;
rectMode(CENTER);
ellipseMode(CENTER);
stroke(200);
fill(c);
rect(enemyX,y,thesize,thesize/2);
fill(200);
ellipse(enemyX - offset,y - offset,offset,offset/2);
ellipse(enemyX + offset,y - offset,offset,offset/2);
ellipse(enemyX - offset,y + offset,offset,offset/2);
ellipse(enemyX + offset,y + offset,offset,offset/2);
}
void drawEnemy1(int x, int y, int thesize1, color c) {
int offset1 = thesize1 / 4;
rectMode(CENTER);
ellipseMode(CENTER);
stroke(200);
fill(c);
rect(enemyX1,enemyY1,thesize1,thesize1/2);
fill(200);
ellipse(enemyX1 - offset1,enemyY1 - offset1,offset1,offset1/2);
ellipse(enemyX1 + offset1,enemyY1 - offset1,offset1,offset1/2);
ellipse(enemyX1 - offset1,enemyY1 + offset1,offset1,offset1/2);
ellipse(enemyX1 + offset1,enemyY1 + offset1,offset1,offset1/2);
}
void drawEnemy2(int x, int y, int thesize1, color c) {
int offset1 = thesize1 / 4;
rectMode(CENTER);
ellipseMode(CENTER);
stroke(200);
fill(c);
rect(enemyX2,enemyY2,thesize1,thesize1/2);
fill(200);
ellipse(enemyX2 - offset1,enemyY2 - offset1,offset1,offset1/2);
ellipse(enemyX2 + offset1,enemyY2 - offset1,offset1,offset1/2);
ellipse(enemyX2 - offset1,enemyY2 + offset1,offset1,offset1/2);
ellipse(enemyX2 + offset1,enemyY2 + offset1,offset1,offset1/2);
}
void drawEnemy3(int x, int y, int thesize1, color c) {
int offset1 = thesize1 / 4;
rectMode(CENTER);
ellipseMode(CENTER);
stroke(200);
fill(c);
rect(enemyX3,enemyY3,thesize1,thesize1/2);
fill(200);
ellipse(enemyX3 - offset1,enemyY3 - offset1,offset1,offset1/2);
ellipse(enemyX3 + offset1,enemyY3 - offset1,offset1,offset1/2);
ellipse(enemyX3 - offset1,enemyY3 + offset1,offset1,offset1/2);
ellipse(enemyX3 + offset1,enemyY3 + offset1,offset1,offset1/2);
}
void drawEnemy4(int x, int y, int thesize1, color c) {
int offset1 = thesize1 / 4;
rectMode(CENTER);
ellipseMode(CENTER);
stroke(200);
fill(c);
rect(enemyX4,enemyY4,thesize1,thesize1/2);
fill(200);
ellipse(enemyX4 - offset1,enemyY4 - offset1,offset1,offset1/2);
ellipse(enemyX4 + offset1,enemyY4 - offset1,offset1,offset1/2);
ellipse(enemyX4 - offset1,enemyY4 + offset1,offset1,offset1/2);
ellipse(enemyX4 + offset1,enemyY4 + offset1,offset1,offset1/2);
}
void drawEnemy5(int x, int y, int thesize1, color c) {
int offset1 = thesize1 / 4;
rectMode(CENTER);
ellipseMode(CENTER);
stroke(200);
fill(c);
rect(enemyX5,enemyY5,thesize1,thesize1/2);
fill(200);
ellipse(enemyX5 - offset1,enemyY5 - offset1,offset1,offset1/2);
ellipse(enemyX5 + offset1,enemyY5 - offset1,offset1,offset1/2);
ellipse(enemyX5 - offset1,enemyY5 + offset1,offset1,offset1/2);
ellipse(enemyX5 + offset1,enemyY5 + offset1,offset1,offset1/2);
}
void drawEnemy6(int x, int y, int thesize1, color c) {
int offset1 = thesize1 / 4;
rectMode(CENTER);
ellipseMode(CENTER);
stroke(200);
fill(c);
rect(enemyX6,enemyY6,thesize1,thesize1/2);
fill(200);
ellipse(enemyX6 - offset1,enemyY6 - offset1,offset1,offset1/2);
ellipse(enemyX6 + offset1,enemyY6 - offset1,offset1,offset1/2);
ellipse(enemyX6 - offset1,enemyY6 + offset1,offset1,offset1/2);
ellipse(enemyX6 + offset1,enemyY6 + offset1,offset1,offset1/2);
}
void drawEnemy7(int x, int y, int thesize1, color c) {
int offset1 = thesize1 / 4;
rectMode(CENTER);
ellipseMode(CENTER);
stroke(200);
fill(c);
rect(enemyX7,enemyY7,thesize1,thesize1/2);
fill(200);
ellipse(enemyX7 - offset1,enemyY7 - offset1,offset1,offset1/2);
ellipse(enemyX7 + offset1,enemyY7 - offset1,offset1,offset1/2);
ellipse(enemyX7 - offset1,enemyY7 + offset1,offset1,offset1/2);
ellipse(enemyX7 + offset1,enemyY7 + offset1,offset1,offset1/2);
}
void drawEnemy8(int x, int y, int thesize1, color c) {
int offset1 = thesize1 / 4;
rectMode(CENTER);
ellipseMode(CENTER);
stroke(200);
fill(c);
rect(enemyX8,enemyY8,thesize1,thesize1/2);
fill(200);
ellipse(enemyX8 - offset1,enemyY8 - offset1,offset1,offset1/2);
ellipse(enemyX8 + offset1,enemyY8 - offset1,offset1,offset1/2);
ellipse(enemyX8 - offset1,enemyY8 + offset1,offset1,offset1/2);
ellipse(enemyX8 + offset1,enemyY8 + offset1,offset1,offset1/2);
}

Chrisir

Re: Re: Creating a Simple Enemy AI

11 months ago

Yeah, you want an array (list) of enemies. Then you for loop the list. One enemy is an object of a class Enemy (with x,y,speedx...).

See e.g. Reference for Array etc.
http://www.processing.org/reference/
or in the wiki under technical faq
http://wiki.processing.org/w/Technical_FAQ
here as PhiLoho said (further below):
From several variables to arrays

See also learning object oriented programming / OOP:
http://www.processing.org/learning/objects/

wilcapriv

Re: Creating a Simple Enemy AI

11 months ago

I think when i rework this for my final ill make and array and a class we haven't gone over it yet in class my concern now is making it so that I can actually hit them with some sort of bullet and hit detection.

It looks really cool ^^
http://www.understandingnewmedia.com/p4a/f2012/wilbert_r/exercise_5/

not_55

Re: Creating a Simple Enemy AI

11 months ago

As Chrisir says, you really should look at using a simple array - it'll massively reduce the amount of typing you're doing which has the most important benefit of reducing the source of errors and unexpected behaviour.

Without getting bogged down with classes etc, you could use an array to store the position and speed of each enemy...

float[][] enemyData = new enemyDate[20][3]

Would give you storage for the x, y and speed data for 20 enemies, stored like this

enemyData[enemynumber][x position][y position][speed]

enemy number 0 might be .......enemyData[0][76][404][3]
enemy number 5 might be ...... enemyData[5][200][300][-7]

Say you wanted to stop all the enemies from moving....

for(int i=0; i<20; i++)
enemyData[i][2]=0;

//the [2] above is because speed is stored in the third index [0][1][2]

A lots less typing :)

Maybe you want to line all the enemies up near the top of the screen at y=30....

for(int i=0; i<20; i++)
enemyData[i][1]=30;

//y co-ord is in second index [1]

You get the idea :D

PhiLho

Re: Creating a Simple Enemy AI

11 months ago

Probably of interest: From several variables to arrays

wilcapriv

Re: Creating a Simple Enemy AI

11 months ago

Thanks guys ^^ I will definably look at this in the morning and redo the code and take arrays into account, right now I'm burned out and can't even created a simple star field ' '.

Chrisir

Re: Creating a Simple Enemy AI

11 months ago

hello,

not_55's solution is very elegant - but it might be easier for you to have an array of all x,
another array of all y, a 3rd array of all speeds, 4th of all sizes etc.
I think this in the link PhiLho posted.

At pos 5 in all arrays are the data for car number 5 etc.

Then you can say

rect( arrayX[index], arrayY[index], arraySize[index], arraySize[index]/2);
fill(200);
ellipse(arrayX[index] - offset, arrayY[index] - offset, offset, offset/2);

and use this in a for loop (here with the variable index).
then you need only one function move, bounce and drawEnemy.

Greetings, Chrisir

not_55

Re: Creating a Simple Enemy AI

11 months ago

Hi Chrisir

I did think of doing that first for simplicity but thought it better to use a multi-dimensional array as it reduces further the chance for error because...

x[current]
....
speed[current]

'current' could have been inadvertantly changed in the meantime

Chrisir

Re: Creating a Simple Enemy AI

11 months ago

absolutely!
It's all compromises as long as he can't turn to classes...

In your approach we could name the indices to improve readability
e.g. in Say you wanted to stop all the enemies from moving....

final int indexForSpeed = 2;
....
for(int enemy_i=0; enemy_i<20; enemy_i++)
enemyData[enemy_i][indexForSpeed]=0; // stop it: Speed is 0.

Chrisir

Re: Creating a Simple Enemy AI

11 months ago

find a basic shooter here:

http://www.openprocessing.org/sketch/77863

wilcapriv

Re: Creating a Simple Enemy AI

11 months ago

Thanks guys I finally woke up and gonna start trying to fix up my code, everyone here is so helpful, i just want to say thank you again, I have a basic understanding of syntax and coding so reading the code I have no problem sometimes i get caught up in making my changes work, and feel a little intimidated.

wilcapriv

Re: Creating a Simple Enemy AI

11 months ago

Thanks Chrisir great example I was going to look at the text book and see if they had something similar I really appreciate a step in the right direction.