Commit Graph

11650 Commits

Author SHA1 Message Date
Thomas Harte caffe56a2d Slightly expanded width of cathode ray gun, decided to figure out exactly how to deal with off-by-one lengths and precision at a later date, ensured that failure to catch vertical sync doesn't cause out-of-bounds buffer access on the hard-coded, assumed large enough, 512x512 data textures. 2015-07-27 00:28:47 -04:00
Thomas Harte 65bb31d55b With around about a thousand issues, not the least of which being sometimes unsafe memory accesses, I've at last got pixels on screen. 2015-07-26 23:50:43 -04:00
Thomas Harte cd0a62d21e With a slight tweak to the informal protocol used for 6502 memory access cycles, ensured the wait strobe actually halts the CPU, to give a more accurate linking of machine time to real time. 2015-07-26 15:55:19 -04:00
Thomas Harte 8efd449834 Switched to a down counter and a reset test that remains unconditional but doesn't depend on % (which seems to turn into a big imul-powered deal). Probably pointless mulling around the edges at this point. 2015-07-26 15:45:19 -04:00
Thomas Harte 6252f6030f Switched to idiomatic source name, ensured latest project name is in all appropriate header places, threw texture coordinates slightly into the shader mix. 2015-07-26 15:25:11 -04:00
Thomas Harte e53fbcf9ea Reshuffled to make the OpenGL view explicitly a conduit for CRT-style output, and to give it responsibility for frame drawing. Which is still an awkward thread hop for the time being, but I've yet to read up on the advocated approach to multithreading with an NSOpenGLView; it looked like special provisions were available. 2015-07-26 15:13:46 -04:00
Thomas Harte dd428c5d4d Slightly relaxed time it takes to recognise vertical sync; considered what to do about reviving proper vertical sync but then gave up. 2015-07-24 23:56:25 -04:00
Thomas Harte 78a91b67c5 Quickie: make sure the correct context is adjusted; use the intended convertPointToBacking:. 2015-07-24 23:42:19 -04:00
Thomas Harte cea2580000 Upped internal precision a little. 2015-07-24 23:36:44 -04:00
Thomas Harte ecb2898bd5 The overall architecture of who has responsibility for what is now very askew but: the CRT now outputs a tightly packed short buffer, with the probable OpenGL destination in mind. So it's now all fixed arithmetic internally. CRTFrame is reduced to a plain C struct with the intention that the OpenGL view will take responsibility for it and stop doing the back-and-forth sprint on getting buffer data. The Atari 2600 now outputs explicit blanks rather than level blacks for its border, so that it's easier visually to debug the CRT in its form as far as it has currently progressed: to drawing lines where the cathode ray gun would run while outputting pixel. I note that I'm still not quite getting vertical sync right yet — I'm just accepting it anywhere in teh frame — but that should be an easy fix. 2015-07-24 23:29:45 -04:00
Thomas Harte 5ab47e600a Got through the requisite amount of invisible pain to get something onto my GL display. But clearly this is factored in entirely the wrong way. Work to do. 2015-07-24 20:37:08 -04:00
Thomas Harte 31338ef754 Okay; having no minimum size is a user experience nightmare. Fixed. 2015-07-23 22:54:17 -04:00
Thomas Harte 44e8ffd01c Ensured windows start and remain 4:3, made sure I request a GL 3.2 context and that an exception is raised if I call any old-fashioned GL functions. 2015-07-23 22:51:53 -04:00
Thomas Harte 02c786520a More fiddling in the margins in advance of doing the OpenGL stuff: window now supports full-screen display. 2015-07-23 20:53:26 -04:00
Thomas Harte b9721d1d3f Okay, treading water slightly, ensured window content is correct aspect ratio. 2015-07-23 20:50:50 -04:00
Thomas Harte 7276c77027 A full communication pathway now leads to Atari2600.mm (for now) being in possession of a frame and receiving a command to draw, with a suitable OpenGL context being active and whatever is drawn subsequently appearing. 2015-07-23 20:45:07 -04:00
Thomas Harte 0611646181 This then is what the serial dispatch queue and the triple buffer achieve together: I can post the runs over to the main thread for processing while emulation continues separately. 2015-07-23 20:16:48 -04:00
Thomas Harte e7237c7bd5 Switched to forcing all processing onto a common queue and piping the completed frame over into the Objective-C class. 2015-07-23 20:07:35 -04:00
Thomas Harte d72287a776 Looked up normal retrace time (it's a lot less than 16µs and 26 scanlines — more like 7 and 10) and that the visible portion of a line is defined to start about 12 µs after the start of hsync, put the first two numbers into my CRT to make that more accurate, then derived a newer guess about what the Atari 2600 does for each of its 228 cycles. The text version of a frame is now looking pretty good. So it's probably time to hit OpenGL and the OS X side of things. Though I'll have a quick look to find out whether I can learn the exact real Atari 2600 timings before moving on. 2015-07-23 19:24:25 -04:00
Thomas Harte 33c06baffa Explicitly separated vertical and horizontal sync event tracking, so as explicitly to be able to handle a coincidental simultaneous occurrence of both. Also for clarity. 2015-07-23 18:53:18 -04:00
Thomas Harte 529f61caa1 Removed a stray newline. 2015-07-22 20:45:21 -04:00
Thomas Harte 5203f31bf4 Reintroduced a console examination of the output runs being received after fixing a failure to complete or restart frames over in the CRT; weirdly it seems that sync is being obeyed but raster position is off. So work to do. 2015-07-22 20:45:10 -04:00
Thomas Harte 065050115f Made an attempt to switch to a triple-buffering scheme for CRT outputs, with an eye towards asynchronicity. 2015-07-22 20:33:20 -04:00
Thomas Harte b503e13380 Fix one: vertical scan speed was failing to allow for the number of cycles in a line. 2015-07-22 18:56:35 -04:00
Thomas Harte 963cb2f6fb Attempted to switch to slightly more meaningful names within the CRT and implemented a delegate to investigate output. Working on it. 2015-07-22 18:15:18 -04:00
Thomas Harte 908c171d2d Commented the heck out of this thing, to put my thoughts in order if nothing else. 2015-07-21 16:37:39 -04:00
Thomas Harte a1a1b15d18 Made a quick attempt to accumulate a list of detected output runs. Which means finally having to specify normal frame height. I'm already at too many magic formulae though, so this will need proper revision when I'm next awake. Definitely my horizontal position advancement is way off. 2015-07-20 23:18:56 -04:00
Thomas Harte 4fa315ab4d This looks a lot closer to correct. The loss of horizontal sync during vertical sync is odd but the two should be fully decoupled in here. I'll have to check. Probably I've got something wrong. There are approximate sinusoidals when re-establishing sync, so that's promising as to the flywheel. 2015-07-20 21:58:32 -04:00
Thomas Harte 4695295dd1 Made complete attempt at sync discrimination. But I seem somehow to be locking such that horizontal sync is in the middle of the line. Obviously my flywheel is at fault somehow. 2015-07-20 21:43:00 -04:00
Thomas Harte 4e4c082a05 Made some minor attempt at proper sync response. I think I've gone way off piste and overcomplicated it. 2015-07-19 23:43:22 -04:00
Thomas Harte 4a1e9fe2a8 Rephrased the CRT as owning an arbitrary number of buffers and vending storage space for pixel output. That much better maps to potential implementations of this thing in GLSL, with ES 2.0's limitations kept in mind. 2015-07-19 21:21:34 -04:00
Thomas Harte 7df5025eef Started sketching out the delegate interface that will allow a branch from the CRT into whatever native display system is used by a particular platform. 2015-07-19 18:32:42 -04:00
Thomas Harte 4d1e410150 Fix 1: _horizontalTimer should be treated as read only out here. 2015-07-19 16:51:11 -04:00
Thomas Harte 6f78ecdc9c Made first genuine attempt at outputting a meaningful CRT stream. Which shows some significant errors. So work to do. 2015-07-19 16:48:14 -04:00
Thomas Harte 2d0f861474 Incoming: a 'CRT' class, to receive information intended for a cathode ray tube. To decode sync, etc. 2015-07-19 13:36:27 -04:00
Thomas Harte 03a25c8ff2 Fixed playfield pixel logic. 2015-07-19 10:56:04 -04:00
Thomas Harte 12746b35e3 Ensured there's no overflow while changing base. 2015-07-19 10:54:19 -04:00
Thomas Harte 412e02fdd8 Merge branch 'master' of github.com:TomHarte/CLK 2015-07-19 10:52:15 -04:00
Thomas Harte e0aa1e9f19 Minor project rearrangement to aid findability. 2015-07-17 09:10:23 -04:00
Thomas Harte 195c8a87d8 Introduced enough logic that the Atari 2600 is being run, at least. No output yet though because (i) it has no-one to send output to; and (ii) there's nobody that knows how to display output. Hmmm. 2015-07-16 22:14:40 -04:00
Thomas Harte 4496493e85 Performed the bare necessary steps to get my little OpenGL view to create a CVDisplayLink and then repaint itself in time with the display. 2015-07-16 21:16:21 -04:00
Thomas Harte 1df2c48668 Introduced my GL view as the window content. 2015-07-16 21:01:49 -04:00
Thomas Harte 5160b6bbb8 Separated out different test suites into different XCTest subclasses. 2015-07-16 20:52:16 -04:00
Thomas Harte 3e0679235a This now goes just far enough to create an instance of Atari2600::Machine and push a ROM to it. Next jobs are to get a basic CRT emulation wired up, outputting to the window. 2015-07-16 20:40:46 -04:00
Thomas Harte 24c0579b94 Shuffled things and guessed at things until the Xcode project was happy being subservient to the project proper. 2015-07-16 20:27:31 -04:00
Thomas Harte 65d60f065d Started importing unit tests aplenty for the 6502. 2015-07-16 20:15:30 -04:00
Thomas Harte 6558ae1425 Imported what little I have so far in the way of a memory-access cycle complete 6502 and just enough of a pretend Atari 2600 on top to be able to see some playfields in ASCII art. 2015-07-16 19:56:02 -04:00
Thomas Harte b8947a9aaf Created and imported all the necessary Xcode stuff to create an OS X document-based project that declares itself able to open .a26 files. 2015-07-16 19:53:53 -04:00
Thomas Harte 93e76458a8 Create README.md 2015-07-16 19:47:37 -04:00
Thomas Harte 4cae5e187a Initial commit 2015-07-16 19:46:52 -04:00