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8088 Domination: A new FMV method for 8088 PCs

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    #31
    Jim, you are psycho. Can't believe this! Just ran it on my 5150, sure enough it works perfectly!

    I read on your blog that the encoder is actually a compiler and the player loads the code for each frame and has the CPU execute it directly. I'll say it again. You are a freakin' psychopath dude. Brilliant. I wouldn't have ever thought to do it that way.
    sigpic

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      #32
      Originally posted by pearce_jj View Post
      As delta blocks are dropped, so it becomes steadily more out-of-line - does the encoder cope with that, by redrawing some small percentage each frame for example?
      Yes, as each time a new frame is loaded, the deltas are recalculated against whatever is currently displaying out of screen memory. This is adjustable via a threshold parameter though; you can have it always ignore screen, always consult screen, or any percentage inbetween. This was done to favor picture integrity at one extreme and framerate at the other extreme.

      Originally posted by Great Hierophant View Post
      I tried the demo on my Tandy TX, and it does work except for the wrong colors in the first half of the demo.
      Now that's dedication! I want it clear that I did not ask you to do that

      Originally posted by chjmartin2 View Post
      It is cool to me how the encoder really evolved to a hand-in-glove kind of fit with the processor instead of a more traditional data-stream / execution stream arrangement. Nice hardware/software harmonic symphony. Sweet.
      Now you know why I love the demoscene so much. Oldskool productions adhere to that kind of harmony and there is always some clever bit in every production.

      Originally posted by Mike Chambers View Post
      You are a freakin' psychopath dude.
      My "favorite" comment so far
      Offering a bounty for:
      - A working Sanyo MBC-775 or Logabax 1600
      - Music Construction Set, IBM Music Feature edition (has red sticker on front stating IBM Music Feature)

      Comment


        #33
        Originally posted by Mike Chambers View Post
        I read on your blog that the encoder is actually a compiler and the player loads the code for each frame and has the CPU execute it directly. I'll say it again. You are a freakin' psychopath dude. Brilliant. I wouldn't have ever thought to do it that way.
        About 1/3rd (overall) of all GM light vehicles produced in model years 12, 13, 14, 15, and probably 16 have the welcome animations and power flow animations drawn using compiled bitmap deltas created off-line. A custom compiler does something similar to Domination. It analyzes complexity of the delta from one frame to the next - actually to the second frame from current because of double buffering. If under a threshold, it emits C code to draw the delta to a passed-in frame buffer pointer argument with light optimization of the generated code. It then runs the generated code for each frame through GCC with heavy optimizations and thumb2 output enabled. I found GCC actually does a better job optimizing for ARMv7 than I could do by hand at a first pass. For larger complexity frames, a straight gzip of the raw frame data is performed and stored. Everything gets linked to a binary blob with a table of contents at the front. There wasn't a video decoder on the SoC.

        Compiled sprites were nothing new in the 80s. Quite a few parallax scrollers used them including a game I wrote in 1989!
        "Good engineers keep thick authoritative books on their shelf. Not for their own reference, but to throw at people who ask stupid questions; hoping a small fragment of knowledge will osmotically transfer with each cranial impact." - Me

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          #34
          Thoroughly impressive effort Jim!


          Originally posted by Trixter View Post
          PCjr/Tandy can't play digitized audio without consuming 90% of the entire machine, so that's out of the question, sorry
          You realise the irony of that statement, given how you managed to pull off the seemingly-impossible-leap over your corruption work..

          One 'quick and dirty' method that I would've envisaged to help reduce the CPU workload, would be (for example) to initialize one (or more) channels of the SN76496 to output the maximum possible tone frequency (125KHz) and then modulate the corresoponding 4-bit attenuation register? It would probably sound terrible but anyway..
          Last edited by basman74; June 21, 2014, 01:04 AM.
          - Check out my projects website: www.fleasystems.com

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            #35
            Originally posted by basman74 View Post
            One 'quick and dirty' method that I would've envisaged to help reduce the CPU workload, would be (for example) to initialize one (or more) channels of the SN76496 to output the maximum possible tone frequency (125KHz) and then modulate the corresoponding 4-bit attenuation register? It would probably sound terrible but anyway..
            That's not the tough part -- the CPU-consuming part is modulating it 8000 times a second. Interrupt overhead is not free
            Offering a bounty for:
            - A working Sanyo MBC-775 or Logabax 1600
            - Music Construction Set, IBM Music Feature edition (has red sticker on front stating IBM Music Feature)

            Comment


              #36
              Originally posted by Trixter View Post
              That's not the tough part -- the CPU-consuming part is modulating it 8000 times a second. Interrupt overhead is not free
              Thinking about it more, you're right that is a major issue. I wonder if it could be done via some form of software polling of Timer0/2 in the 8253 instead of using interrupts?
              - Check out my projects website: www.fleasystems.com

              Comment


                #37
                Congrats on making Hack-A-Day!
                "Good engineers keep thick authoritative books on their shelf. Not for their own reference, but to throw at people who ask stupid questions; hoping a small fragment of knowledge will osmotically transfer with each cranial impact." - Me

                Comment


                  #38
                  You made it onto OSNews too... one of my usual hangouts since I'm an OS whore.
                  Last edited by deathshadow; June 22, 2014, 01:25 AM.
                  From time to time the accessibility of a website must be refreshed with the blood of owners and designers. It is its natural manure.
                  CUTCODEDOWN.COM

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                    #39
                    Tried it on my CDP 1600. Colors look nice on the CGA composite out, but the cheap 8-bit RLL hard drive controller I threw at it couldn't keep up.

                    What hard drive controller did you use with this? I guess I just need to get a XT-CF-Lite or XT-IDE anyway

                    Comment


                      #40
                      I used a high-performance one (ADP50) but I tested it with an XT-CFv3 board in PIO mode and it was able to keep up.

                      There is a bug in the buffering code -- when the buffer gets exhausted, it doesn't properly rebuffer. I will fix that before I release all the source and tools.

                      An RLL controller + drive with an optimal interleave should be able to sustain 90KB/s which should do a respectable job of playing the demo back; if you are using the default 6:1, it might be worth re-testing with spinrite or equivalent.
                      Offering a bounty for:
                      - A working Sanyo MBC-775 or Logabax 1600
                      - Music Construction Set, IBM Music Feature edition (has red sticker on front stating IBM Music Feature)

                      Comment


                        #41
                        I'm using a WD1004-27X and an interleave of 4. According to Spinrite, that is optimal for that machine. I'll fiddle with that a bit more.

                        Looking closer, I was wrong about the colors, my machine or composite-to-VGA converter is displaying them way off. Is there a good program for testing the CGA artifacting mode? This CDP CGA card does a few odd things too.

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                          #42
                          Not sure what you mean by "testing" -- I think if you've noticed they're way off, there's your test

                          Vile Rancour wrote a small program called WHICHCGA.COM that displays an image that helps you identify if you have the "old" or "new" style CGA card; a search of this forum might turn it up. Tandy 1000 systems output CGA composite mode with the hue shifted 180 degrees (!) and I've been told the PCjr composite output is also slightly off but I can't remember by how much.
                          Offering a bounty for:
                          - A working Sanyo MBC-775 or Logabax 1600
                          - Music Construction Set, IBM Music Feature edition (has red sticker on front stating IBM Music Feature)

                          Comment


                            #43
                            FYI, the trimmer on the 5150 PC and 5160 XT motherboards is used to adjust the CGA artifact colors. It adjusts the system's 14.31818 MHz clock crystal timing, which in turn adjusts the timing of the video signal after it gets through a few dividers to produce the 3.579545 MHz NTSC color burst frequency.

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                              #44
                              Unfortunately, I don't know if any of the trimmers on my CDP 1600 are a color adjust. There are three of them and they are located under the floppy drive housing, so I will have to take those apart to get to them.

                              What I meant by test, was just some kind of calibration tool that would display a reference image in that specific mode. The CGACAL tool only uses normal text mode.

                              Anyway, here are some images I captured from my thing-a-majig:
                              cgacal.jpg
                              dom2.jpg
                              whichcga.jpg

                              Comment


                                #45
                                CGACAL is an RGB calibration test only; you can't use it for composite output.

                                I'm not an expert but it looks like a +80-degree hue shift -- which means I have no idea what is going on.
                                Offering a bounty for:
                                - A working Sanyo MBC-775 or Logabax 1600
                                - Music Construction Set, IBM Music Feature edition (has red sticker on front stating IBM Music Feature)

                                Comment

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