Thelen Posted January 7, 2003 Share Posted January 7, 2003 I'm trying to re-use vertically players.....but i don't get it to work, and i don't know how exactly Who can give some information on how to do this ? Thanks, Thelen Quote Link to comment Share on other sites More sharing options...
+Cafeman Posted January 7, 2003 Share Posted January 7, 2003 Here is something that even I can help with!! I've done this many times... All you do is draw your 2 sprites data at different memory locations withing the Player "strip". FOR EXAMPLE -- if you are using Player1 and say it starts at $1A00. Copy the Alien1 data starting about $1A20 or so to put it at the top of the screen. Copy the Alien2 data at about $1AA0, which puts it lower on the screen. Player1's horizontal position is controlled via register HPOSP1. If you do nothing else, you will see both Aliens, at top and bottom, but they will always have the same horizontal position. That is why you need to change the HPOSP1 register in a mid-screen Display List Interrupt. So, in Vertical Blank (or in a Modeline1 DLI) set HPOSP1 to Alien1's HPOS variable setting. In a DLI mid-screen (Between the 2 sprites), set HPOSP1 to Alien2's HPOS variable setting. I hope that helps. As far as collision, you must determine the height on-screen to determine which of the 2 aliens was collided with/shot etc. Quote Link to comment Share on other sites More sharing options...
Nukey Shay Posted January 7, 2003 Share Posted January 7, 2003 Yeah...and the DLI's can be placed on any graphic line. So if you used a higher graphics mode, you have more opportunities to split the player up. If you have a gap of at least one line in-between the enemy sprites, you could use one DLI (on the scanline with the gap) to change the color...and another DLI (on the scanline with the object data) to change HPOS. Quote Link to comment Share on other sites More sharing options...
+Cafeman Posted January 7, 2003 Share Posted January 7, 2003 There's enough time to change both actually. In each DLI there are 3 phases. Right after the usual "STA WSYNC" stmt, you can lda / sta two times each & should be enough time (it always was for me). If you need more time you can just do some code in the DLI then have an additional "STA WSYNC" and some more code which in effect is like another DLI call but without the administration of pointing the DLI routine to the new code. Then, finally end the long DLI with the RTI. Quote Link to comment Share on other sites More sharing options...
emkay Posted January 7, 2003 Share Posted January 7, 2003 If you need more time you can just do some code in the DLI then have an additional "STA WSYNC" and some more code which in effect is like another DLI call but without the administration of pointing the DLI routine to the new code. Let me guess: You are using an Emulator, do you? With only one WSYNC, the rest of the DLI is synchronized to the screen. In ADMIRANDUS Start-/Manual-Screen, I used only one 1 DLI for the Background, and the Color changes 10 times per scanline at the small screen-setting (32Bytes wide) Maybe, in full screenwidth, there are 16 changes in a scanline. Nothing is flickering With a WSYNC there were only one Color in one scanline... I've used Charmode... So, for easy calculating, the WSYNC costs about 16 times of a real color Change. Quote Link to comment Share on other sites More sharing options...
Thelen Posted January 7, 2003 Author Share Posted January 7, 2003 thanks guys. I think I understand it now (haven't tried anything yet) I was doing things with pmbase switching....and changing the Pcolors....haha. The only thing is off course that if I re-use player0 the re-used player will have thesame color as player0, or I should use a kernel... Thelen Quote Link to comment Share on other sites More sharing options...
emkay Posted January 8, 2003 Share Posted January 8, 2003 thanks guys. I think I understand it now (haven't tried anything yet) I was doing things with pmbase switching....and changing the Pcolors....haha. The only thing is off course that if I re-use player0 the re-used player will have thesame color as player0, or I should use a kernel... Thelen It is no Problem to change the color of the PMG in the same DLI on wich you are changing the position of the player. Quote Link to comment Share on other sites More sharing options...
Nukey Shay Posted January 8, 2003 Share Posted January 8, 2003 Yep...and if you wanted to have multiple objects, you could use tables to hold HPOS and color values. Quote Link to comment Share on other sites More sharing options...
+Cafeman Posted January 8, 2003 Share Posted January 8, 2003 I used STA WSYNC to wait until the start of the next horizontal blank. That's what I thought it did. If that isn't technically correct, I still mean 'the next scanline'. I don't know what you mean emkay, about using an emulator. Maybe you mean emulators act differently. Atari800win seems to act pretty darn close to the real thing. For example, one DLI: ... STA WSYNC lda #$70 sta COLBK STA WSYNC lda #$76 sta COLBK ... rti Well, I'm not looking at the code & its been months since I did it but I think that is the gist of what I was talking about. I don't think it really applies here since I believe you have plenty of time to change more than one value in a DLI on a scanline. Quote Link to comment Share on other sites More sharing options...
Heaven/TQA Posted January 8, 2003 Share Posted January 8, 2003 here my little code to understand the stuff: p0 = $6200 p1 = $6280 p2 = $6300 p3 = $6380 org $4000 ; clear the player data in memory BEFORE enabling them ; so no gfx trash will be on screen init lda #255 ; the player dummy data (%11111111) ldx #0 init0 sta p0,x sta p2,x inx bne init0 ;now initialise the hardware ldx #3 init1 lda #1 ; double sized players sta 53256,x ; size of the players lda #15 ; white color sta 704,x ; color register dex bpl init1 lda #48 sta 53248 ; set player0 on xpos = 48 lda #64 sta 53249 ; set player1 on xpos = 64 lda #$60 sta 54279 ;pmbase i could be wrong here... lda #3 ; player/missle gfx enabled sta 53277 lda #46 ; dma on sta 559 endloop jmp endloop rts when we do assembling then you should get 2 white stripes on screen. now replace the endloop routine with this endloop lda #15 ; white color of player0 sta $d012 lda #48 sta 53248 lda $d40b ; vcount = rasterline of the electro beam cmp #$40 ; wait until 64 rasterlines passed (well...not 100% correct but) bcc endloop sta $d40a ; now sync CPU with rasterbeam to avoid flickering lda 53770 ; get random number 0-255 sta $d01a ; write into background color lda #128 ; new position of player0 sta 53248 lda #$ff ; yellow color sta $d012 ; hardware register of color player0 jmp endloop you will get (hopefully...i haven't tested the code) that player0 is splittet into 2 vertically... this actually is not a DLI but a so called "kernel" routine... display list interrupts (DLIs) can be easily set and can be controlled easily... be creative using DLIs... you can do everything you want with DLIs... even split the pokey sound registers vertical... ps emkay... befor we here restart the DLI discussion... the guy is just starting using DLIs so don't let us "confuse" him with more technical stuff... Quote Link to comment Share on other sites More sharing options...
Thelen Posted January 8, 2003 Author Share Posted January 8, 2003 thanks, thanks ! I have re-used my players!!!....and I understand it !!!. actually its very simple with a DLI. And yes, changing the color is simple too (off course, when i think about it now) Thelen Quote Link to comment Share on other sites More sharing options...
emkay Posted January 8, 2003 Share Posted January 8, 2003 be creative using DLIs... you can do everything you want with DLIs...even split the pokey sound registers vertical... To correct this ... You can just program the POKEY Sound-Channels thru the DLI, but it is not possible to "split" them Quote Link to comment Share on other sites More sharing options...
Nukey Shay Posted January 8, 2003 Share Posted January 8, 2003 Not even with an axe? I am a licensed maniac. j/k Quote Link to comment Share on other sites More sharing options...
emkay Posted January 8, 2003 Share Posted January 8, 2003 Not even with an axe? I am a licensed maniac. j/k I think, with an AXE, you can split the whole computer. Quote Link to comment Share on other sites More sharing options...
+Cafeman Posted January 8, 2003 Share Posted January 8, 2003 Humor (humour?) me ... why would you want / need to change Pokey Registers in a DLI? Quote Link to comment Share on other sites More sharing options...
Nukey Shay Posted January 8, 2003 Share Posted January 8, 2003 So you can pokey sixty times a second and make rabbits envious? I dunno...I prefer to take my time. @emkay You're right...that is probably overkill. Quote Link to comment Share on other sites More sharing options...
emkay Posted January 8, 2003 Share Posted January 8, 2003 Humor (humour?) me ... why would you want / need to change Pokey Registers in a DLI? While playing Samples and DLIs are active, you'll notice crackles. Because the Computer does wait for a WSYNC without doing anything. A clever programmer could create a routine, that plays samples ( a Sample-Step)while a DLI before the WSYNC occurs to reduce the crackles. @Nukey Shay The difference is, that splitted registers can simply moved together by Software Quote Link to comment Share on other sites More sharing options...
Heaven/TQA Posted January 8, 2003 Share Posted January 8, 2003 well... check it out... split the sound registeres via dli and you get 8 ones... maybe you ruin the speakers but it definitly works... no joking... hve Quote Link to comment Share on other sites More sharing options...
emkay Posted January 8, 2003 Share Posted January 8, 2003 well... check it out... split the sound registeres via dli and you get 8 ones... maybe you ruin the speakers but it definitly works... no joking... hve All you're doing thru this is some kind of sampling. Do you really think, the ANTIC is that allmighty, don't you? All that a DLI does is to use some CPU-Time to change registers while the Screen is built on the TV. You can, due to a softwaretiming, do the same... like on ST. This wrong thinking exists since it was known, that Players are multiplexable in a DLI. But even the GTIA is able only to display one Player at one Time. Multiplexed Players are even not displayed at one time.... think about it. Quote Link to comment Share on other sites More sharing options...
Heaven/TQA Posted January 9, 2003 Share Posted January 9, 2003 emkay... check it out... you don't believe me... do you? it's more like sampling... because i do write into the sound freq register as well... not just the "volume".... i don't know if its useful or not... but... f.e. you can try to do a "real" overscan as well... real means display more than 240 scanlines... i had a scroller done "above" the 1st scanline antic can produce... how? accidently the display began to roll after a too long display list... but correcting this "on the fly" somehow my code managed to stop the rolling and my scroller was above the 1st scanline... (no... i don't mean the $70,$70,$70 area... i mean above the 1st scanline) it was around 1991 as far as i remember... unfortunatly the code was just working on my machine and on my TV set... hve Quote Link to comment Share on other sites More sharing options...
emkay Posted January 9, 2003 Share Posted January 9, 2003 @Heaven/TQA >emkay... check it out... you don't believe me... do you? >it's more like sampling... because i do write into the sound freq register as well... not just the "volume".... OK.... Sampling was the wrong word. But you only switch the Soundregisters and get two "Voices" which are not clear. Because they are not clear, due to the fact, that they are not played at one time.. But, you may use that for special Soundeffects... >f.e. you can try to do a "real" overscan as well... real means display more than 240 scanlines... i had a scroller done "above" the 1st scanline antic can produce... how? accidently the display began to roll after a too long display list... but correcting this "on the fly" somehow my code managed to stop the rolling and my scroller was above the 1st scanline... (no... i don't mean the $70,$70,$70 area... i mean above the 1st scanline) No Problem. In NTSC there are 60Hz. The GTIA produces for PAL a 50Hz screen , so there are two black borders on the top and on the bottom of the screen.. Is the DL to long, the Screen switches to 60Hz, that a PAL TV cannot handle. The Screen rolls and the Borders are gone.... A switch in the right Moment, and on the TV, you'll have an extra "Display". The Line cannot be "killed" due to the fact, that the Scanline is not refreshed on the TV.... until the next VB. >it was around 1991 as far as i remember... unfortunatly the code was just working on my machine and on my TV set... No doubts about that. Quote Link to comment Share on other sites More sharing options...
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