929 Commits

Author	SHA1	Message	Date
Thomas Harte	1819e7b9cc	Started sketching out an appropriate interface to transfer responsibility for shaders to the CRT.	2016-01-23 19:06:32 -05:00
Thomas Harte	ace331d4b4	Got a bit higher level in CRT timing specification. Which internally allows it now to infer the colour clock frequency. Which will be helpful momentarily.	2016-01-23 18:53:20 -05:00
Thomas Harte	a9e26d7808	Introduced a scan's delay, as intended.	2016-01-23 17:49:25 -05:00
Thomas Harte	20cab08f8f	Added a two-slot buffer of scans and a comon dispatch mechanism.	2016-01-23 17:44:34 -05:00
Thomas Harte	0efe4b312c	Disabled my various bits of rate interchange debugging; improved test for when to call update_display due to a RAM write.	2016-01-21 22:16:52 -05:00
Thomas Harte	48ddd3c497	Set about documenting the CRT; while doing so decided to add an optional clock divider for input; having done so decided to try to exploit it with the Electron.	2016-01-21 21:17:47 -05:00
Thomas Harte	4c16d34063	Moved set_tape so that the inline definition of get_next_tape_pulse is visible to it. Also eliminated some dead typedefs.	2016-01-20 08:27:25 -05:00
Thomas Harte	f727582911	Started making first moves towards stripping CSCathodeRayView of its responsibilities. If that can be merely an OpenGL view that presents things, things will be a lot more portable.	2016-01-20 08:21:33 -05:00
Thomas Harte	e65cd4cf06	Some data is marginally reaching the CPU from the tape.	2016-01-19 22:05:34 -05:00
Thomas Harte	ddcc34740b	Added lots of debugging output while I attempt to locate the source of audio scratchiness, also simplified manner of dealing with wraparound within the AudioQueue wrapper.	2016-01-18 13:50:19 -06:00
Thomas Harte	b58e59e2bb	Fixed: now outputting the requested output rate, rather than massively overproducing at the input rate.	2016-01-14 23:12:40 -05:00
Thomas Harte	383b2be4c6	Fixed one off-by-one error.	2016-01-14 21:33:27 -05:00
Thomas Harte	8bd04a6be4	Switched model for filter subclasses. Implemented test square[-ish] wave to check for obvious stream errors. None is clear.	2016-01-14 21:27:02 -05:00
Thomas Harte	38ffcaa262	Here, at last, is _some_ audio output, at least.	2016-01-14 20:33:22 -05:00
Thomas Harte	afde8dac49	Closed the loop such that audio manages to bubble up into Objective-C.	2016-01-13 22:38:59 -05:00
Thomas Harte	439d452e23	Resolved some errors.	2016-01-13 22:11:33 -05:00
Thomas Harte	49e89a4bcb	I'm not yet completely convinced by my approach to time basing, but it'll probably do? If so then this more or less gets me ready for a point-sampled filtering.	2016-01-13 22:02:39 -05:00
Thomas Harte	d9a7ef9e46	Edging towards audio output; the speaker is given appropriate input and output rates, and then updated with current divider and enabled/disabled status.	2016-01-13 21:03:43 -05:00
Thomas Harte	84ba4e2900	Tidied a little, started working towards supporting speaker output.	2016-01-12 22:19:56 -05:00
Thomas Harte	3437781abd	Started sketching out an interface for sound generation. Which made me realise that the CRT in CRTDelegate was redundant, since C++ has namespaces.	2016-01-12 16:54:09 -05:00
Thomas Harte	82aa6d074a	'type' is out, at least for the time being.	2015-09-05 20:25:30 -04:00
Thomas Harte	3c3c4d2f7c	Enlarged drawing range a little.	2015-08-19 21:35:26 -04:00
Thomas Harte	28fad66272	Okay, so I had those constants transposed. What a klutz I've been!	2015-08-19 09:09:00 -04:00
Thomas Harte	f74d9ee373	Copied in quote. So that I can stop looking it up.	2015-08-18 22:36:32 -04:00
Thomas Harte	a62c7f5c56	At last! Discovered CRT scanning bug; was always moving by the full proposed run length along the scan, not the time until the next event. Using this, have implemented proper vertical sync at last (I think). Have disabled scanline banding too, as now everything meets up it's more helpful to be able to see with clarity.	2015-08-18 22:22:47 -04:00
Thomas Harte	88d5064737	Not that it makes a lot of difference, there being no names to mangle, but moved the closing #ifdef __cplusplus to the idiomatic place.	2015-08-18 20:33:59 -04:00
Thomas Harte	902795d61c	Switched vertical sync detection method, at least for now. They never happen automatically (I need to fix that) and just always take effect if detected in the lower half of the display. PAL/NTSC is determined just by looking at the refresh rate.	2015-08-18 00:17:03 -04:00
Thomas Harte	083b678785	Quickie: observed that the initial position is one scanline dirty, not zero. Also switched to a size_t on the write pointer, size_t being the correct C size for into-memory offsets.	2015-08-17 00:25:32 -04:00
Thomas Harte	cde9bb7ebc	Put common shift step into a macro.	2015-08-16 16:12:20 -04:00
Thomas Harte	a693c081f8	Switched on the appropriate compiler warnings re: signed comparisons and implicit conversions. Fixed all less-than-explicit calls.	2015-08-16 16:08:29 -04:00
Thomas Harte	b440fed323	Fixed a couple of incorrect references to horizontal constants or calculations where the intention is to use vertical.	2015-08-13 18:29:07 +01:00
Thomas Harte	59c872ada6	Attempted to reintroduce suitably noted emergency flyback. To re-enable auto-selection of PAL.	2015-08-13 14:55:53 +01:00
Thomas Harte	aebf636528	Ensured the PIA timer resumes its normal tick rate after being read; fixed those spaces that had crept in where tabs should be.	2015-08-10 16:55:16 +01:00
Thomas Harte	fd36f13baf	The cathode ray view no longer hard codes the frame size. So that's one less coupling. Doubled pixel output size to give sufficient sampling detail to capture the NTSC colour clock (ummm, hopefully).	2015-08-05 21:45:47 -04:00
Thomas Harte	67e82c713f	Broke assumption that every item in a vertex description is a short, specifically turning lateral into a byte. Which buys me a byte for phase, if that's sufficient.	2015-08-05 21:12:33 -04:00
Thomas Harte	5644b3a1cc	Fixed scanline sizing and fill issues, as well as shortening vsync to the correct Atari length.	2015-08-05 20:55:27 -04:00
Thomas Harte	265d1d5b24	Merge branch 'EdgeTriggeredVSync'	2015-08-05 20:30:02 -04:00
Thomas Harte	84d1c2e47d	Fixed end of sync time calculation and ensured the pretend capacitor is emptied by the decision to retrace and doesn't refill during retrace.	2015-08-05 20:29:20 -04:00
Thomas Harte	04c2640b15	Made a quick attempt to allow vsync triggers only on the raising edge of a sync signal. Will need to investigate more thoroughly.	2015-08-03 08:42:05 -04:00
Thomas Harte	5313b48ebd	I'm ashamed to admit, I: played with numbers until enough things looked stable such that I can investigate other things. Discovery: my PAL autodetection was way off. Fixed, hopefully.	2015-08-02 20:32:18 -04:00
Thomas Harte	55017b78a5	Made an attempt to unify my variable storage (and, technically, to get beam size correct across the frame).	2015-08-02 19:30:45 -04:00
Thomas Harte	6e52e5df1c	Full separate 'lateral' usage is go. Also probably at some point I need to throw in a phase property, which this new flexibility will help with.	2015-08-02 14:32:29 -04:00
Thomas Harte	3ab6585789	Started making the format of data included in a CRTFrame less a matter of variously hard-coded magic constants. Which will allow me to separate the idea of an internal lateral position from the direct texture coordinate, avoiding precision sampling errors at the top and bottom.	2015-08-02 14:25:21 -04:00
Thomas Harte	be421587ad	Eliminated the vertical retrace counter; vertical retrace ends when the beam gets back to the top.	2015-08-02 13:48:35 -04:00
Thomas Harte	de4f2bf5dd	Maybe the 10 lines resource I saw meant 10 lines including charge time?	2015-07-31 19:00:40 -04:00
Thomas Harte	5f1d76e855	Can't seem to find any documentation: assumed horizontal sync is generated during vertical.	2015-07-31 18:49:02 -04:00
Thomas Harte	c1a12ad4df	Fix to make sure end of vertical sync is always correctly spotted as an event, rather than just happening off the books. So I can now watch Joust roll to its heart's content.	2015-07-31 18:15:59 -04:00
Thomas Harte	9c91f1a2eb	Added an attempt at NTSC/PAL autodetection, based on number of missed vertical syncs.	2015-07-31 18:04:33 -04:00
Thomas Harte	a5d66e9dd6	Factored out a few more constants, started trying to ensure there's enough slack and the mechanisms in place for the CathodeRayView to hold onto two frames if it desires, for potential phosphor simulation, switched once again to additive blending — much more like a real CRT — and added a sine function across the width of spans per my understanding of how an electron gun actually fires. ... Why do all this when overall timing is still so far off? It helps me more easily see how overall timing is so far off.	2015-07-31 17:47:10 -04:00
Thomas Harte	6ad3fbbaf2	Slowed flywheel adjustments a little, the better to highlight phase errors for the time being.	2015-07-30 23:00:54 -04:00
Thomas Harte	cfe758daa0	A tweak here, a tweak there, to help with debugging.	2015-07-30 21:29:40 -04:00
Thomas Harte	20c2d98b9a	Converted remaining spaces to real tabs.	2015-07-30 20:51:32 -04:00
Thomas Harte	1fa7a77793	Continuing in my attempts to figure out the complete absence of graphics from some games: there are 262 lines on an NTSC screen, not 256. Also ensured that the CRT has a little spare range at the edges so that its generated triangles don't wrap around just because of integer overflow.	2015-07-30 20:07:20 -04:00
Thomas Harte	98efae2536	Reintroduced emergency vertical sync — so that output occurs even when the emulation isn't catching syncs properly — and switched some spaces to tabs.	2015-07-30 17:16:49 -04:00
Thomas Harte	596d34190c	Fixed: write pointer is calculated only after write x and y are known. This is probably the memory handling problem?	2015-07-28 08:15:54 -04:00
Thomas Harte	1f229ee6f7	More tweaks to provide a stable image, at least for the time being.	2015-07-27 20:18:25 -04:00
Thomas Harte	01109d441b	Made an attempt at NTSC colours. Hard coded in RGB, not composite. Short cuts, tsk.	2015-07-27 19:04:03 -04:00
Thomas Harte	31e9a53a44	Removed some debugging code.	2015-07-27 16:43:51 -04:00
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	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	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	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	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	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