Search found 1044 matches

by SarahWalker
Wed Feb 21, 2018 9:15 pm
Forum: projects
Topic: New game - tube type thingy
Replies: 38
Views: 1751

Re: New game - tube type thingy

Haven't posted an update for a bit! I've put the optimisation stuff aside, and started trying to make an actual game out of this. I put together a level editor - after the headache of writing the While Light editor in Win32, I wrote this one in C#, and made as much progress in a couple of hours as I...
by SarahWalker
Mon Jan 29, 2018 5:33 pm
Forum: software: new games
Topic: New Release: Retro Software's WHITE LIGHT by Sarah Walker
Replies: 62
Views: 3599

Re: New Release: Retro Software's WHITE LIGHT by Sarah Walker

Commie_User wrote:
SarahWalker wrote:I think I'm a real person, at least...


Is that your picture in the gallery?

If only!
by SarahWalker
Tue Jan 23, 2018 9:06 pm
Forum: projects
Topic: New game - tube type thingy
Replies: 38
Views: 1751

Re: New game - tube type thingy

How about checking to see if the 4 pixels you're about to write are the same as what's already there? Not sure how much use this will be over the Tube - I think you meant to say 'if the _host_ is indeed the bottleneck'? If the parasite is the bottleneck then this will surely just make it worse! I s...
by SarahWalker
Mon Jan 22, 2018 9:52 pm
Forum: projects
Topic: New game - tube type thingy
Replies: 38
Views: 1751

Re: New game - tube type thingy

How about checking to see if the 4 pixels you're about to write are the same as what's already there? Ooh, good catch! Just implemented this on the single processor version. While it doesn't quite fit into 3 frames with sprites onscreen, it does keep a nice stable 4 frames now. Overplotting the spr...
by SarahWalker
Sat Jan 13, 2018 1:27 pm
Forum: projects
Topic: New game - tube type thingy
Replies: 38
Views: 1751

Re: New game - tube type thingy

Bit of a philosophical question now - I've had a play with increasing the tube resolution on the copro version, from 64x56 to 64x112. This works, but drops performance slightly, from 16.7 fps back down to 12.5. Which do people prefer? 64x56, 16.7 fps - https://www.youtube.com/watch?v=QTwrO2SD734 64x...
by SarahWalker
Mon Jan 08, 2018 5:50 pm
Forum: projects
Topic: New game - tube type thingy
Replies: 38
Views: 1751

Re: New game - tube type thingy

On the master can you use a number of swr bank so that you have 70k of loads and writes to the screen buffer so no x or y indexes are used? The Master hasn't got 70k of SWRAM... In any case I'm currently using 1 bank for the source bitmap for the tunnel, and sprites currently spill to 2 banks and w...
by SarahWalker
Mon Jan 08, 2018 5:46 pm
Forum: projects
Topic: New game - tube type thingy
Replies: 38
Views: 1751

Re: New game - tube type thingy

20% ish... not a win then. That depends. Even 0% is a win if the extra 64K of RAM is useful. And with PiTubeDirect out there, it could be that there are more people with BBC B, sideways RAM, 6502 second processor (=112K) than a BBC Master (=128K). I think you might be confused here? The 20% was for...
by SarahWalker
Sun Jan 07, 2018 5:23 pm
Forum: projects
Topic: New game - tube type thingy
Replies: 38
Views: 1751

Re: New game - tube type thingy

OK. Hands up everyone who thought, based on the subject line, that this was going to be a game that took advantage of a second processor? (-8 Just implemented this, actually! The game still mostly runs on the host CPU, but the parasite is used to assist with the tube rendering. The parasite runs th...
by SarahWalker
Sun Jan 07, 2018 5:07 pm
Forum: projects
Topic: New game - tube type thingy
Replies: 38
Views: 1751

Re: New game - tube type thingy

62 cycles for LUT stuff, 20 cycles total for texture load, 83 cycles for store. So this would (in theory!) be 62*2 = 124 cycles for LUT, 20*2 = 40 cycles for texture load, plus some cycles to swap SWRAM banks between texture colour and texture colour*3 (12 at minimum), then 83 cycles for store. So 2...
by SarahWalker
Sun Jan 07, 2018 11:23 am
Forum: projects
Topic: New game - tube type thingy
Replies: 38
Views: 1751

Re: New game - tube type thingy

The sprite plotter is column-major Don't know why I originally did this, row-major turned out to be faster! The column-major inner loop looked like this, unrolled 4 times : lda (spraddr) tax lda (scraddr), y and masktable,x ora ortable,x sta (scraddr), y inc spraddr * iny bne + inc scraddr+1 inc sc...
by SarahWalker
Sun Jan 07, 2018 11:09 am
Forum: projects
Topic: New game - tube type thingy
Replies: 38
Views: 1751

Re: New game - tube type thingy

I'm sure Sarah will correct me if I'm wrong, but it looks like she's using a bitplanes type scheme like Firetrack, so two bits per pixel for the tube, and the other two bits for moving sprites - which unfortunately would rule out extra NuLA colours, or using the palette for intermediate animation f...
by SarahWalker
Sun Jan 07, 2018 11:08 am
Forum: projects
Topic: New game - tube type thingy
Replies: 38
Views: 1751

Re: New game - tube type thingy

Can you use palette swapping to double the frame rate of the tube with sacrificing colours? A four colour tube + swap would eat all 16 colours (same 4 colour sprites :( ) but you could draw a 3 colour tube with 9 palette entries and leave 7 colours for sprites perhaps. Changing what 3 colours they ...
by SarahWalker
Tue Jan 02, 2018 10:09 pm
Forum: projects
Topic: New game - tube type thingy
Replies: 38
Views: 1751

Re: New game - tube type thingy

Arcadian wrote:Neat! I remember Tube ...

Could you post some video of it running? (the Master version that is!)

Here you go!

https://www.youtube.com/watch?v=fmJezG66038
by SarahWalker
Mon Jan 01, 2018 5:42 pm
Forum: projects
Topic: New game - tube type thingy
Replies: 38
Views: 1751

Re: New game - tube type thingy

For sprites, the requirement to handle scaling & rotating sprites means that a more flexible sprite system is required than the one used by White Light, which used an unrolled plot routine with fixed size sprites. Obviously this is going to use a _lot_ of sprites, so there needs to be some kind ...
by SarahWalker
Mon Jan 01, 2018 5:38 pm
Forum: projects
Topic: New game - tube type thingy
Replies: 38
Views: 1751

Re: New game - tube type thingy

The tube effect is table driven. A 32x32 table is built as : dx = 31.5 - x dy = 31.5 - y dist[y][x] = (16384.0 / (dx*dx + dy*dy)) ang[y][x] = (atan2(dx, dy) * (128.0 / M_PI)) + 128.0 dist and ang are used as U and V coordinates into a 64x64 texture stored in SW RAM. The game plots a 64x56 render usi...
by SarahWalker
Mon Jan 01, 2018 5:36 pm
Forum: projects
Topic: New game - tube type thingy
Replies: 38
Views: 1751

New game - tube type thingy

Back at ABUG in November, just after I finished White Light, I had a play with a basic tube effect : tubeeffect.gif Though blocky, it runs reasonably smoothly (12.5 fps) and could have been part of a demo. However, back in 1995 or so, I used to have an old Bullfrog PC coverdisk game called Tube : tu...
by SarahWalker
Thu Dec 14, 2017 5:39 pm
Forum: software: new games
Topic: New Release: Retro Software's WHITE LIGHT by Sarah Walker
Replies: 62
Views: 3599

Re: New Release: Retro Software's WHITE LIGHT by Sarah Walker

I noticed a puzzling thing last night while playing WL. At first, the power ups behaved normally, giving me a wide angle double shot, then adding a third etc. However after playing a few attempts I found that I only ever got a narrow angle double shot, no matter how many additional power ups I coll...
by SarahWalker
Mon Dec 11, 2017 12:30 pm
Forum: software: new games
Topic: New Release: Retro Software's WHITE LIGHT by Sarah Walker
Replies: 62
Views: 3599

Re: New Release: Retro Software's WHITE LIGHT by Sarah Walker

mygrandmawheels wrote:Can you satisfy my curiosity?
Is Sarah Walker a real person or is it a fictitious name that identifies a development group?

I think I'm a real person, at least...
by SarahWalker
Thu Nov 30, 2017 5:40 pm
Forum: upcoming and recent events & exhibitions
Topic: ABUG SOUTH 1 to 3 June 2018 (Hampshire) BOOKING THREAD
Replies: 17
Views: 1047

Re: ABUG SOUTH 1 to 3 June 2018 (Hampshire) BOOKING THREAD

I think I should be able to make this. Saturday/Sunday with kit.
by SarahWalker
Wed Oct 18, 2017 5:38 pm
Forum: off-topic
Topic: Bladerunner 2049
Replies: 6
Views: 619

Re: Bladerunner 2049

pixelblip wrote:You know they will do another one for the money!

Unlikely - it appears to have flopped.
by SarahWalker
Wed Oct 18, 2017 4:52 pm
Forum: off-topic
Topic: Bladerunner 2049
Replies: 6
Views: 619

Re: Bladerunner 2049

I thought it wasn't bad, though certainly not a five-star film like some of the reviews I've seen are claiming! From what I remember, the best bits were usually when it wasn't trying to be a Blade Runner sequel and was doing it's own thing. I think it would have been better as a totally standalone f...
by SarahWalker
Tue Oct 03, 2017 4:45 pm
Forum: software
Topic: RISC iX - Cloned!
Replies: 168
Views: 17755

Re: RISC iX - Cloned!

I doubt any of the RISCiX compatible SCSI podules are available in an A4000-friendly 8-bit minipodule form.
by SarahWalker
Sat Sep 09, 2017 6:22 am
Forum: software: games - high scores
Topic: White Light High Score Challenge for Beta Testers
Replies: 37
Views: 2183

Re: White Light High Score Challenge for Beta Testers

Just wanted to thank everyone who participated in this. It's given me confidence that a) the game isn't completely broken :D and b) it isn't impossibly difficult - being normally difficult is perfectly acceptable in my book!

Anyway, a handful of tweaks/fixes and WL should be ready for wider release!
by SarahWalker
Mon Jul 31, 2017 5:58 pm
Forum: other vintage computer hardware, software and games
Topic: Turbo XT
Replies: 2
Views: 456

Turbo XT

Inspired by Andy1979's 386 Restoration thread, and martinw's posts a while ago on his IBM XT, I thought I'd share my current project. A while ago I picked up a 10 MHz Turbo XT compatible board. Normally I'd play with this a little and then put it in the box with my other motherboards, I figured I'd ...
by SarahWalker
Wed Jul 26, 2017 4:15 pm
Forum: other vintage computer hardware, software and games
Topic: 386 Restoration
Replies: 7
Views: 769

Re: 386 Restoration

I find it odd that itt will only accept 4Mb of RAM IIRC the 386sx could address up to 16mb, and the motherboard has 8 sockets, so I would have thought that it should be able to access more. Though your simms do need to be fitted in pairs. It may be a genuine limitation, 386SX boards (particularly t...
by SarahWalker
Sat Jul 22, 2017 9:46 am
Forum: hardware
Topic: What would be a suitable D2A resister ladder for the beeb
Replies: 9
Views: 665

Re: What would be a suitable D2A resister ladder for the beeb

I used 10k resistors, and a 1uF electrolytic capacitor. I don't think the exact values matter too much, as long as all the resistors are the same! You shouldn't need anything else, it's a pretty basic circuit. If you haven't seen it, my schematic is at http://stardot.org.uk/forums/viewtopic.php?f=2&...
by SarahWalker
Wed Jul 19, 2017 4:50 pm
Forum: projects
Topic: Experiments in Stable Raster Timing
Replies: 14
Views: 1530

Re: Experiments in Stable Raster Timing

Demo 128 also uses it, for the wobbly 50 fps rotozoomer at the end.
by SarahWalker
Mon Jul 17, 2017 5:11 pm
Forum: general
Topic: Archimedes 30th birthday?
Replies: 12
Views: 1051

Re: Archimedes 30th birthday?

Isn't it the same PCB with different options fitted? At least between the A3xx and the original A440. I remember my 310 definitely having room for the hard disc controller. I think it also had something like 'UNIVERSAL BOARD' written on it somewhere.

The A4xx/1 was a different board.
by SarahWalker
Sat Jul 15, 2017 4:10 pm
Forum: projects
Topic: Experiments in Stable Raster Timing
Replies: 14
Views: 1530

Re: Experiments in Stable Raster Timing

I had thought I was using both main & shadow RAM for the wavy test card, but a quick look at the source shows otherwise - it's using all 32kb of the shadow bank, to store a 128x128x4 (4kb) picture, but doesn't display the main bank. Obviously I thought at the time that non-integer scaling would ...