KO2CV - 0.90

[Steve Camber]

Features

8 tactics mode temporarily removed for this release to allow PM tactics to be used.

75% speed added. 25% speed removed.

Due to the nature of how the speed is controlled, 75% speed can look a bit jerky.

Here's what the CPU decides to do every 1/50th of a second in the 3 modes
100% = DRAW DRAW DRAW DRAW DRAW DRAW DRAW DRAW etc
75% = DRAW DRAW DRAW Pause DRAW DRAW DRAW Pause etc
50% = DRAW Pause DRAW Pause DRAW Pause etc

So therefore 75% does not look as smooth as 100% or 50%. See? Good!

The system I have implemented allows for the speed to be changed anywhere from 1% to 100%.. Not over 100% unfortunately Only these 3 speeds are currently available, but if someone feels their life will be incomplete without a 29% speed, then this is simple to do.

Download

http://www.camber.demon.co.uk/KO2CV

[filippodb]

what a pity, 75% is very bad!!

can you change the frame time from 1/50 to 1/33??

or is 66% better??

66% = DRAW DRAW Pause DRAW DRAW Pause DRAW DRAW Pause etc

[Steve Camber]

66% looks quite similar to 75%.. just a bit slower!

[Abyss]

8 tactics mode temporarily removed for this release to allow PM tactics to be used.

Bad bad bad

Let Robert play with his Oracle disk. Bring back the 8 tactics!

The system I have implemented allows for the speed to be changed anywhere from 1% to 100%.. Not over 100% unfortunately Only these 3 speeds are currently available, but if someone feels their life will be incomplete without a 29% speed, then this is simple to do.

Shouldn't this be anywhere from 2% to 100% in steps of 2%?

[Steve Camber]

Let Robert play with his Oracle disk. Bring back the 8 tactics!

8 tactics are back in v0.91.

Shouldn't this be anywhere from 2% to 100% in steps of 2%?

No.

[Abyss]

Let Robert play with his Oracle disk. Bring back the 8 tactics!

8 tactics are back in v0.91.

Shouldn't this be anywhere from 2% to 100% in steps of 2%?

No.

Does this mean that the game logic is updated at a higher rate than the screen?

[Steve Camber]

Imagine drawing a frame, then waiting for 99 frames, that's your 1% speed.

Imagine drawing 99 frames, then waiting for a frame, that's 99% speed.

Game logic is updated once per render.. any faster and the game crashes, or frames would be dropped at least.

[Abyss]

Imagine drawing a frame, then waiting for 99 frames, that's your 1% speed.

Imagine drawing 99 frames, then waiting for a frame, that's 99% speed.

Game logic is updated once per render.. any faster and the game crashes, or frames would be dropped at least.

Therefore, and since the Amiga screen update is fixed at 50Hz for PAL systems, I think that screen updates can only be done 50 times per second, therefore skipping one results in 98% speed, not 99%.

[Steve Camber]

Yes, the VBL clock runs at 50Hz.

So at 1% speed, the amiga just counts up 50 frames in the 1st second. In the next second the amiga just counts up 49 frames. Then for the final frame of the 2nd second it goes through the logic loop and draw the players in their new positions.

At 99% speed, in the 1st second the amiga does 50 logic+renders. In the next second it does 49 logic+renders, followed by 1 wait where it does nothing.

Does that make sense?

[Abyss]

So you spread the drawing over two seconds?

[Bounty Bob]

It's the logical way to split it into single percentages. Two seconds=100 frames.

[Steve Camber]

Here's the offending code:

Code: Select all

gGameSpeeds:   dc.w      100
            dc.w      75
            dc.w      50


public DoVBlank:

            movem.l      d0,-(a7)
            move.w      GameSpeedOption(A4),d0
            lea         gGameSpeeds,a0
            lsl.w      #1,d0
            move.w      (a0,d0),d0


b_waitvbl1:
                TST.W      bVBlank(A4)
               BEQ         b_waitvbl1
            CLR.W      bVBlank(A4)

b_loopVBL:
            add.w      d0,gVBLcountup
            cmp.w      #100,gVBLcountup
            bge         b_noMoreVBL

                CLR.W      bVBlank(A4)
b_waitvbl2:
                TST.W      bVBlank(A4)
                BEQ         b_waitvbl2
            bra         b_loopVBL
b_noMoreVBL:
            CLR.W      bVBlank(A4)
            sub.w      #100,gVBLcountup
            movem.l      (a7)+,d0
            rts



[Freshmaker]

Here's the offending code:

Code: Select all

gGameSpeeds:   dc.w      100
            dc.w      75
            dc.w      50


public DoVBlank:

            movem.l      d0,-(a7)
            move.w      GameSpeedOption(A4),d0
            lea         gGameSpeeds,a0
            lsl.w      #1,d0
            move.w      (a0,d0),d0


b_waitvbl1:
                TST.W      bVBlank(A4)
               BEQ         b_waitvbl1
            CLR.W      bVBlank(A4)

b_loopVBL:
            add.w      d0,gVBLcountup
            cmp.w      #100,gVBLcountup
            bge         b_noMoreVBL

                CLR.W      bVBlank(A4)
b_waitvbl2:
                TST.W      bVBlank(A4)
                BEQ         b_waitvbl2
            bra         b_loopVBL
b_noMoreVBL:
            CLR.W      bVBlank(A4)
            sub.w      #100,gVBLcountup
            movem.l      (a7)+,d0
            rts



I'm very offended by this post.