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Everything posted by MarcoJ

  1. This is fun. Thanks for posting. The crosshair offset after firing mechanic makes the game challenging. It makes the player try to find the best time to shoot rather than just mowing things down.
  2. Hi, Is there a document that describes the CU Custom Bankswitching protocol for the Harmony Cart? I may be wrong, but I understand it serves as a way to upload new bankswitching types to the Harmony without updating the BIOS; knowing the limitations of 32K ROM / 6K RAM have been declared on other posts. I'm working on a 32k E7 scheme and am wondering the feasibilities of implementing that on the Harmony cart. Currently it emulates OK with my dev Stella build. I would rather find out now if it's possible, than develop a white elephant that can only be emulated and not run on a regular Harmony. Cheers Marco
  3. Studying Room of Doom's disassembly

    1. BydoEmpire


      I always wanted that game based on a review, but never saw it in a store back in the day nor in the wild since.

    2. MarcoJ


      It's an amazing game. Only found out about last week. Never even heard of it. 

    3. DoctorSpuds


      Great game. Mines of Minos might also be worth your time if it hasn't popped up on your radar yet.

  4. MarcoJ

    Movie Cart

    Ah, I wondered about this prospect. I recall CDFJ being able to take advantage of fast swapped immediate loads from its data bank/selection logic. The part I was unsure about was if CDFJ could be able to source the dataset from SD card, rather than only its internal paged ram bank/ data bank.
  5. MarcoJ

    Movie Cart

    I had a quick look at the kernel in operation. It's fast. It is able to use all of A, X, Y with immediate loads(2 cycle) to zero page stores (3 cycle) at precisely the right time to get GRP0/GRP1 to have the right colour and data. It has no dedicated need for using X or Y for tracking the scanline number, nor for using indexed reads with the +2 cycle penalty. I haven't looked into the hardware, but i'm guessing those immediate load arguments get swapped out on a line by line basis by the hardware.
  6. Thanks for the support @Prizrak
  7. lol. Do I see Grogu there? Yes the gaps do help convey separation for monochrome coloured objects side by side and also vertically. In Pitkat R3 I've made character objects and ladders still 7px wide, which yes does leave them off centre. The move to gapless helps the soil/concrete and bitmaps gel together moreso than the characters. Cheers Marco
  8. Hi All, The R3 version of Pitkat has been released. It is available at the top of the forum. Release Notes R3 2021-03-31 1. New graphic engine to remove horizontal and vertical gaps. 2. Adjustments of tiles to become 8 pixels wide (instead of 7). Kats have longer tails! 3. Adjustments of tiles to mesh vertically without a gap. 4. Adjustment of bitmapped backgrounds to take advantage of the new graphics engine 5. Simplification of floor graphic during gameplay. Marco J.
  9. yes, yes. This is cool. I like the concept. Keep it coming. The enemies are varied and the strategy to defeat them is fun. That guy who drops the big pink blocks I rush attack him. Whereas the grendade dropper and the arrow shooter i take my time on. I have never pressed fire so quickly on the part where you drop and there's a blue buy pacing back and forth. I made it to the first boss and got my ass handed to me. Good stuff. Keep it going.
  10. Wow! I've just heard the news that a full motion video implementation with sound has been fully developed by a developer called Iodefmode aka @rbairos. It will run full length movies on a custom cartridge called a "Moviecart" on the Atari 2600. It is going to make its debut on the @ZeroPage Homebrew show on Tue Mar 30 6PM PT | 9PM ET | 2AM GMT. This is exciting news!
  11. Indeed. this is the exact same reported fault. If you see on ZPH's historical show at 26:50, the same thing happens. Interestingly, when they switched consoles several weeks later the problem stopped. You are the 3rd user to report this issue on their console.
  12. Interesting indeed. Thanks for the feedback. This happened on 2 other user's machines with Pitkat. I'm hoping to understand the reason one day.
  13. Wow, cool. Does it crash immediately on load, or it runs for a while?
  14. 27-3-21 Added a new version of Simpsons where Horizontal colour resolution is doubled by use of a flicker technique i'm dubbing "Venetian Comb". Looks best on a CRT and in Stella with "Phosphor TV Effect" enabled, 60% or better. If you pause Stella you can see how it works. See top of forum for download. Cheers - Mark.
  15. Oh wow! That is awesome. And 2003! Sorry for getting it wrong Andrew, I have updated the spiel above. There is someone on youtube putting up videos of Atari demos. I think it must have been an old alpha?
  16. Whoa...Did you end up making a colour version? I recall it from a while ago now, seeing a cascading colour on the sides and B/W in the centre. Have I missed this breakthrough?
  17. 2-4-21 - A more developed concept called the "Moviecart" has just been made publicly aware as of 30-3-21. Check it out, it's incredible. Introduction - It was of interest to know if the Pitkat kernel could be used to play colour video. - The original need of the video concept was to test a glitch Pitkat caused on [email protected] console. - Colour video has been done before in 2003! Dancing Baby by Andrew Davie. Check it out below. - A fully developed video concept was released to public knowledge 30-3-21 called the Moviecart. See above. - Monochrome video has been done before - Bad Apple demo. - My implementation allows a 64 x 32 pixel monochrome texture with an 8 x 8 colour cell matrix, with 1 of 128 colours available for each colour cell. - Can change colour and texture in one frame, allowing 60 frames per second video. It can be slowed down too to 30 fps, 20fps 15fps, etc. - Uses a newly developed kernel for Pitkat Revision 3 which exploits an undocumented TIA glitch which helps achieve drawing of the screen without vertical and horizontal gaps between tiles. - To produce the video information during compile time, video data is encoded in 2 processes to produce texture and colour data. - The process uses tools such as ImageMagick, GIMP, Binary to Hex converter and Excel. - So far, grayscale thesholding and edge detecting have been used to create the monochrome textures. - Creating the colour data involves shrinking each frame to an 8x8 image and extracting the colour. The shrinking process averages the colour over the whole colour cell area into a single colour that’s used for the colour cell. - With E7 16k bank switching, it can fit 30 frames in the ROM. This is equivalent to 1 second of video at 30 frames per second. This is obviously very limiting. - Even if the ROM was expanded to be 512kB, this would still be only 32 seconds of footage. - The bigger picture of the concept would be to able to stream video from an SD card. Such concepts have been implemented on early computers such as the ZX Spectrum with aftermarket SD card interfaces. - The current video bitrate is 10 kBit/s, or 36 Megabytes per hour. With a 16GB card, it would be possible to store 444 hours of footage. - There is currently no video compression whatsoever. Textures and colours are stored in a Raw format in order to provide maximum throughput. Given the huge capacity of SD cards, this isn’t a problem. Overall Impressions - Movement is the most important requirement for footage to be believable. - Large, fluidly moving objects contrasting against the background seem to work the best. - Scenes with large patches of similar colours work better than scenes with many contrasting coloured objects. - It struggles with static and detailed scenes as they are lost in the low resolution graphics and limited colour cells, especially horizontally. - Scenes containing a lot of black are also problematic as the colour cell averaging process tends to pick black as the dominant colour and this causes large sections to become invisible. An example of problematic footage would be a space scene or night footage. Future Goals - The next goal was to have sound. 8 kHz, 4 bit digitized sound could accompany the video. The concept is yet to be proven. It is estimated that the video bitrate would double to 20 kBit per second. (72 MB/hour). - With more cart RAM, it would be possible to host a second kernel to fill the interlaced lines using 30 Hz flicker. - The ultimate goal was to stream video off an SD card. This has already been achieved now by the Moviecart. Thus, this concept will not develop further. - It should be possible to increase the resolution of the video from 64 to 96 pixels with Bus Stuffing. This scheme should be capable of updating texture and colour cells for a complete Medium space triple copied players venetian blinds kernel(12 x 8 pixels horizontally). Conventional banking schemes are unable to match this throughput. Perhaps this will eventuate one day.
  18. Hi All, An implementation of a FMV (full motion video) concept for the Atari 2600 has been developed, based on the Pitkat kernel. The resolution is 64x32 pixels with 64 colour cells, running at 30 fps. ** This was demonstrated on the Zero Page Homebrew Show on 2021-03-19. ** Demonstration Files Here are 3 demonstration videos stored on 16 KB ROMs. 1. Rally. This shows an airborne rally car land onto the ground. The texture is created with thresholding. The fast movement on the car and scenery helps the viewer believe the animation. The detail of the scene is not as important as the movement. Colour plays a small role in conveying the sky, mountainside and the road. 2. Sprintcat. It’s a video of a cat sprinting on grass. The texture is also created with thresholding. The large size and fluid movement of the cat encoded into the black texturing helps the scene be believable. The texture is everything in this video; colour doesn’t play a significant role. 3. Simpsons. A video of the Simpsons sitting on their couch. This video uses edge detection rather than thresholding to create solid black lines around the objects, as opposed to relying on large moving black objects used in the first two videos. It uses colour to the highest degree out of all the demos. However, it struggles with an overload of detail and colour in the scene. *EDIT 27-3-21 Added a new version of Simpsons where Horizontal colour resolution is doubled by use of a flicker technique i'm dubbing "Venetian Comb". Looks best on a CRT and in Stella with "Phosphor TV Effect" enabled, 60% or better. If you pause Stella you can see how it works. A detailed explanation is below. Let us know what you think. Cheers, Marco Johannes RALLY E716k.bin SIMPSONS E716k.bin SPRINTCAT E716k.bin SIMPSONS E716k V2 - Venetian Comb.bin
  19. nice one @kisrael. Have been a user of your playerpal for years. Thanks for making this.
  20. Only 20 to go till my Dragonfly is ready!

    1. GoldLeader


      WOOOHOOO!  They're Awesome!!

  21. Thanks @RushJet1. Wow, the percussion one is a great idea. I sparingly use percussion anyway so that's now my arpeggio chord bank. Appreciate you posting the solution.
  22. Lookup tables save the day yet again!

    1. Ryan Witmer

      Ryan Witmer

      There is no problem that cannot be solved by adding a lookup table, except for too many lookup tables.

  23. The game looks fun - saw it on the show. Nice one.
  24. This development is incredible. Being able to use all 6 horizontal sprites with colour is amazing. The RPG demo is jaw dropping. I have been trying to push the limits of the 8 character coloured tile engine I used in Pitkat but I realise now it's not possible, and I think even with CDFJ it's not possible. Bus stuffing is the only way. This will bring out a whole new generation of games. Very cool work!
  25. The Modern Battle WIP demo is released. Please see top of forum for download. Note1, the game at the moment can work without a Quadtari but the controls of two different craft will be ganged together. Note2: This is currently a very, very early alpha. It is a barely working shell of a game currently. There are many features to be added, levels to be created, modes to be invented and bugs to be fixed. I have decided on this game to release it early to the community so it can develop in public view. If you have any feedback, please post it in the forum below.
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