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Simple Game (Read 5606 times)

stopfocus Junior Member Offline Posts: 62	Simple Game Oct 3^rd, 2009, 1:18pm I have decided that the first thing I would try in Process would be to make something similar to some of my old favorite Super Nintendo games Gradius, Darius Twins, Super Nova etc... http://www.openprocessing.org/visuals/?visualID=5136
	« Last Edit: Oct 8^th, 2009, 10:02pm by stopfocus »

stopfocus Junior Member Offline Posts: 62	Re: Simple Game Reply #1 - Oct 4^th, 2009, 4:21pm - Added simple reset button - removed mouse pointer -stopped numbers from spiraling towards infinity at an overwhelming rate

ben_hem

Re: Simple Game
Reply #2 - Oct 4^th, 2009, 4:50pm

Hey,
Reset button does wonders!
I owe you a better explanation of the "separating timing from rendering" thing. If you update at a rate which is directly related to millis(), you'll never have speed issues, and the game will run as smoothly as possible on the given platform. Just break the frameRate limit with some absurd value like frameRate(999); in setup(), and then:

Quote:

int lastCheck=0;
void draw(){
while ((millis()-lastCheck)>=10){
lastCheck+=10;
gameLogic(); // update all movement, etc.
}
gameRender(): // draw everything at its current position
}

Hope this makes sense. The math involved in shifting all your object positions shouldn't take more than 10 milliseconds, but if it does, you'll have to increase 10 to some larger number. So you're shifting at a given speed, 10 times if there are 100 millis between frames, 5 times for 50 millis between frames, etc. Each frame, the objects render at their current position. This way, even if your frameRate swings wildly, you have total control over the game's pace.

--Ben

stopfocus

Re: Simple Game
Reply #3 - Oct 4^th, 2009, 9:34pm

Ok.I understand your suggestion. I just wan't to make sure that I follow the logic.

I'm setting FrameRate to a higher number so that the frame rate is being controlled by the timing of the program?

I am setting the math in a separate step then the render so that the computer makes sure the math is done before rendering the drawing?

That way there is a cushion between the calculations and the render so that a slower computer will pace the same speed as a faster one?

So my speed timings are going to change for everything because the way I am doing it now is based on a FrameRate that varies from computer to computer?

ben_hem

Re: Simple Game
Reply #4 - Oct 4^th, 2009, 10:53pm

almost ...
right now, timing is off for a few reasons. There's an intermittent slowdown due to garbage collection, about every two or three seconds. And frameRate isn't really constant; it's just a measure of your current FPS. When you set frameRate( n ); you're really setting the maximum. If the computer isn't fast enough to meet that maximum, it'll vary somewhere below..and if someone starts a process in the background that uses CPU, framerate will swing wildly on any machine.

So, framerate is changing and can't be used for timing purposes. If you're moving all your objects each frame, and the framerate is changing, your objects are lurching and stopping and so on. The separation of game and render logic means that while you continue to render each frame (which is essential) you can update your movement/collision/whatever data as many times as needed between each frame. Take the while() loop apart piece by piece: it's saying, if the "game time counter" has fallen behind the milliseconds this program's been running, by an amount >= 10, then update the game logic and add 10 to the counter." This repeats until the counter is caught up to whatever that frame's millis() count is.

--Ben

stopfocus

Re: Simple Game
Reply #5 - Oct 4^th, 2009, 11:22pm

So my code should be structured something like this.

class SimpleShip {

float x_locOne=height/2;
float y_locOne=200;
int r1 = 9;
float x_speed;
float y_speed;
float acceleration=.5;
SimpleShip(){
}
//-----------------------------------------------------------------MATH
void calcship(){
x_speed=constrain(x_speed,-2,2);
y_speed=constrain(y_speed,-2,2);

x_locOne=constrain(x_locOne,0+5,width-3);
y_locOne=constrain(y_locOne,0+5,height-3);

y_locOne+=y_speed;
x_locOne+=x_speed;

}

//-----------------------------------------------------------------RENDER

void drawship(){
fill(255,0,0);
ellipseMode(RADIUS);
ellipse(x_locOne,y_locOne,r1,r1);
ellipseMode(CENTER);
fill(255);
}da

//--------------------------------------------------------KEYBOARD EVENTS

void move(){
if ((key=='w')||(key=='W')){
y_speed-=acceleration;
}

if ((key=='s')||( key=='S')){
y_speed+=acceleration;
}

if ((key=='a')||(key=='A')){
x_speed-=acceleration;
}

if ((key=='d')||(key=='D')){
x_speed+=acceleration;
}
}
}

ben_hem Senior Member Offline Posts: 399 CA, US	Re: Simple Game Reply #6 - Oct 5^th, 2009, 9:08am That much looks good, but an aside -- I'd recommend linking your keyPressed events to booleans if you want it to be possible to press multiple direction keys at once. I.e. void keyPressed(){ if key==down, flag down boolean true;}, and void keyReleased(){ if key==down, flag down bool false; } (outside the ship class) -- Ben

stopfocus Junior Member Offline Posts: 62	Re: Simple Game Reply #7 - Oct 5^th, 2009, 9:26pm I added keyboard controls I didn't understand the last part that was suggested about them being outside of the ship class.Also I finished splitting the math and the rendering. Tomorrow I am going to clean up the code and try to adjust the game timing.

stopfocus

Re: Simple Game
Reply #8 - Oct 6^th, 2009, 5:10pm

I set it up how you suggested and everything runs much smoother. Thank you thats a very important technique. Unfortunately it broke my rigged Pause button function located inside of the world class.I'll keep working at it. Any advice?

http://www.openprocessing.org/visuals/?visualID=4876

I have at least figured out what my problem is. When I pause the game its still counting the millis() the program has been running So..... When I unpause the game it runs the math check as if the game was never paused because the variable lastcheck has no been accumulating.

ben_hem

Re: Simple Game
Reply #9 - Oct 6^th, 2009, 10:34pm

Heh, I've never seen noLoop() used as a pause function ;)
noLoop() means "don't loop draw." So once you've called it ...draw never runs again. (Unfortunately keyPresses, etc. depend on draw.) Freeze.
I'd say just use a boolean -- in the draw loop, if (paused) write "paused" on the screen, otherwise do your current draw loop with the game and render logic and all that.
Oh, and P5 structure is a little different from pure Java: you never have to worry about public/static, etc., because P5 *is* a single class. I have my doubts about putting setup() in a .java tab, by the way...but it does seem to work!
--Ben

stopfocus

Re: Simple Game
Reply #10 - Oct 8^th, 2009, 10:01pm

Some times when I have the easiest problems I come up with the craziest solutions.

This is the last update I will do on this. I feel comfortable with working on something I little more difficult now that I have my first little App behind me and understand how to create classes. There are some more things that I'm sure that I will come back and touch up but this is pretty much it.

Thanks for you help Ben

final link
http://www.openprocessing.org/visuals/?visualID=5136

Beatsy YaBB Newbies Offline Posts: 19	Re: Simple Game Reply #11 - Nov 22^nd, 2009, 5:11pm Cool as. I like the sound. Make a downloadable with levels and high scores and stuff. I know people who would love it. Namely my little bro

ellen.ziegelaar YaBB Newbies Offline Posts: 3	Re: Simple Game Reply #12 - Nov 24^th, 2009, 1:58pm This is a good game, I could only get to 1758. What were your first steps in making it? A little bit like Space Invaders!

Beatsy YaBB Newbies Offline Posts: 19	Re: Simple Game Reply #13 - Dec 2^nd, 2009, 2:35pm It is good. The interface is cool. I beat that score got to around 13000. It would be cool to make the ships position in the window the same all the time but have it as a Side Scroller. Josh

stopfocus Junior Member Offline Posts: 62	Re: Simple Game Reply #14 - Dec 27^th, 2009, 6:10am Now with super awsome space missles! http://www.openprocessing.org/visuals/?visualID=5136

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