If I dare make a suggestion; what might be nice now that memory is so large would be to ditch fast loads and saves (or at least significantly demote them) in favour of a simple jog dial. So I'd be able to rewind with, say, frame accuracy for the last five minutes, second accuracy for the five minutes before that, etc.
Obviously you'd want to approach the problem similarly to compressed video, with key frames and the subsequent few stored as delta differences. If you just densely stored the entire state, and pretending it were just the RAM for ease of calculation, 50fps for five minutes is 15,000 frames, for a footprint of 15,000 times 512kb or about 7.3 gigabytes. A key frame each second for five minutes is already only 150mb and the delta changes would likely be light. If you reduced it to just storing input as deltas (whether things the machine inherently reads or things the emulator supplies like disk changes) then they'd cost almost nothing at all either to compute or to store. Good idea? Bad idea? On 22 Mar 2012, at 16:12, "Aleš Keprt" <[email protected]> wrote: Thank you very much. It is a bug in emulator - apparently the end of file mark is not saved correctly. (One zero byte is missing at the end of the file.) And yes, now we are able to finish some games quite easily, for example I finished Exolon yesterday. <wlEmoticon-smile[1].png> Best regards, Aley Keprt *From:* Andrew Gillen <[email protected]> *Sent:* Thursday, March 22, 2012 11:29 PM *To:* [email protected] *Subject:* Re: ASCD 0.98 WIP 2 released Hi Aleš Great work on this emulator. I tried it this evening and it plays a mean game of Dave Invaders <Emoticon3.gif> and even the demo of Dave Infuriators <Emoticon3.gif> <Emoticon3.gif> Quick load and save seems to work great but with one small bug (that I'm sure you know about already but I thought I'd mention anyway) when I Quickload from the Emulation menu it says it fails to load, but actually loads fine. The F9 key doesn't offer up the same error. Anyway, I might actually be able to complete my own game now without resorting to a cheat mode Looking forward to further development. All the best Andrew *From:* Aleš Keprt <[email protected]> *Sent:* Thursday, March 22, 2012 2:26 AM *To:* [email protected] *Subject:* ASCD 0.98 WIP 2 released Hi Sam Users! I just released the new version of my emulator ASCD 0.98 WIP 2. It's still "work-in-progress", but many planned things are already implemented. You can download it from my web site www.keprt.cz - click Download, then see at the bottom of that page. Snapshots are now enabled for use, they are saved to the new file format with extension SCS (aka. Sam Coupe Snapshot). The file format is self-described in the source code (see file SamSnap.cpp). The new fileformat covers also ZX Spectrum 48/128 snapshots, as it is the fileformat used for internal Quicksave/Quickload feature. You can also simultaneously write action replay recording file and use quicksave/quickload. My plan is to add AVI video recording to let people record "walkthrough" videos in games. Until this is implemented, ASCD 0.98 won't reach final state. What's new: ----------------- 0.98 WIP 2 - march 2012 ========== * Sam Coupé Snapshots are now public; next goal is to implement AVI video file writer * The snapshot code is still in development, now supported also for ZX Spectrum modes * QuickSave/QuickLoad feature now uses new snapshot format in all modes, including air recording * New file format for OpenAir recordings - files are now a lot smaller * Sam: Added printer support (wasn't implemented in Windows version yet) - saves to printout.txt * Sam: Improved floppy disk drive emulation, SAMDICE doesn't crash anymore, although it still doesn't work * Sam: Improved mouse emulation code * ZXS: Added support for 3x8bit DAC audio based on IC 8255 (ports 31,63,95,127 - MQM5 works :-)) * ZXS: Added support for Fullerbox AY audio (it's always turned on in ZXS 48/128k mode) * ZXS: Added ZX Printer support - it saves the prints to zxprint.bmp file * Z80: Fixed ADC HL,rr incorrectly setting N flag * Z80: Added support for saving .z80 snapshot files (uncompressed 48KB only) * Mouse was too fast, so it is set 2 times slower than before * Changed contents of a disk images are now saved with a temp filename and then renamed back only if no error occurs 0.98 WIP 1 - march 2012 ========== * First public Win32 version - supports Windows 2000 and later, DirectX 6 (2D) and Direct3D 9 (3D) * MS-DOS version is now officially dropped * Updated to Visual C++ 2008 and Zlib 1.2.6 * Fixed many bugs in the emulation core * Fixed Windows related bugs (especially in GUI) * Added support for saving .sna snaps (both 48k and 128k) * Added many items to Windows menu, but this is still quite incomplete * Fixed wrong flash speed (it flashed every 25 frames, now it flashes every 16 frames) Best regards, Aley Keprt ----------------------------------------- Mgr. Aleš Keprt, Ph.D. private: [email protected], www.keprt.cz office: Moravian College / Moravská vysoká škola Olomouc, [email protected] ----------------------------------------- ----------------------------------------- Mgr. Aleš Keprt, Ph.D. private: [email protected], www.keprt.cz office: Moravian College / Moravská vysoká škola Olomouc, [email protected]
