SpiceWare's Blog

Have you decided what will happen if the ball hits a player's paddle from behind?

Placard sounds good!

 

Also, the game looks great so far!

Have you decided what will happen if the ball hits a player's paddle from behind?

While I don't think it's a problem, in deference to all your help I will be adding a 3rd option to Catch for no-rebounds. It won't be done in time for MGC though, which is why it's not in the placard instructions. Any idea on how to phrase it for that short options field? I don't think Catch: Yes, No or Maybe will cut it

 

 

Also, in case anybody missed it, I added an image to the prior blog entry with a revised shield graphic. Any comments?

While I don't think it's a problem, in deference to all your help I will be adding a 3rd option to Catch for no-rebounds. It won't be done in time for MGC though, which is why it's not in the placard instructions. Any idea on how to phrase it for that short options field? I don't think Catch: Yes, No or Maybe will cut it

 

How about "Safe?" It probably makes for a better computer player game...it's always so sad watching one of the computer players blast their own wall away and then kill themselves in Atari's Warlords.

The Catch won't change the backward collisions, so Safe isn't quite right. I had noticed that problem with Warlords and do plan to address it when I do my AI.

 

As I lay in bed last night I thought up "Limited".

 

Hmm- is the AD quote a directed at me for having a first 2600 project that's 32K

The Catch won't change the backward collisions, so Safe isn't quite right. I had noticed that problem with Warlords and do plan to address it when I do my AI.

 

I don't see any particularly logical reason why having the ball hit the back of the shield with the button pushed should result in a safe catch, while not having the button pushed would result in it bouncing backward. It would seem that if you allow back-hand catches, the ball should go through the paddle from behind.

 

Perhaps a new option: "Backhand Safe/Bounce"

 

BTW, one complaint I have about Warlords that also applies here is that balls always bounce 180 degrees when they hit a brick. It would be much nicer if the balls behaved as in Arkanoid. If a ball straddles or crosses only a vertical edge of the brick, reflect velocity about a vertical axis. If it straddles or crosses only a horizontal edge, reflect velocity about a vertical axis.

 

Assuming X and Y coordinates are defined so that (X and 7)=0 corresponds to the left edge of the ball being aligned with the left edge of a brick, and (y and 3) corresponds to the top edge of the ball being aligned with the top edge of a brick, do something like this:

 sec
 lda ypos_l
 sbc yvel_l
 lda ypos_h
 bit yvel_h
 bpl yvel_positive
 sbc yvel_h ; Compute previous Y position
 adc #1  ; Above ADC should have cleared carry
 eor ypos_h
 and #4
 bne crossed_y
 beq no_cross_y
yvel_positive:
 sbc yvel_h ; Compute previous Y position
 inc ypos_h
 eor ypos_h
 dec ypos_h
 and #4
 bne crossed_y
 beq no_cross_y

The above code should indicate whether the ball crossed between one row of bricks and the next, or is straddling two rows of bricks. Similar code may be used for columns.

 

Making the bounces more Arkanoid-ish would make the game much more interesting. As it is, a ball that's going to hit a brick will simply return via the way it came.

I don't see any particularly logical reason why having the ball hit the back of the shield with the button pushed should result in a safe catch, while not having the button pushed would result in it bouncing backward. It would seem that if you allow back-hand catches, the ball should go through the paddle from behind.

Think of it this way - if somebody tosses a ball at you, you may or may not be coordinated enough to able to reach behind you and catch it, but if you don't it would bounce off your back. I'll think on it, but I doubt I'll change it.

 

BTW, one complaint I have about Warlords that also applies here is that balls always bounce 180 degrees when they hit a brick. It would be much nicer if the balls behaved as in Arkanoid. If a ball straddles or crosses only a vertical edge of the brick, reflect velocity about a vertical axis. If it straddles or crosses only a horizontal edge, reflect velocity about a vertical axis.

Most helpful! I don't like how the ball currently bounces off the bricks either, but hadn't looked into it yet.

Thanks again supercat! The routines worked great with some minor tweeks once I figured out that bit BALLyHigh,y was not a valid command! DASM didn't complain(or I missed the error as it scrolled by) and it took stepping thru the debugger to realize the BIT command wasn't even in the compiled program