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#1
most of problems are due to (i guess) OUT (C),0 undocumented opcode which was fixed (or reassigned) in later versions
#2
Thanks for reporting!
Very interesting, I would like to hear about more testings.
I wonder if the issues with BG-stuff are undocumented instructions or timing.
(btw I really like your Basic hacks!)
Very interesting, I would like to hear about more testings.
I wonder if the issues with BG-stuff are undocumented instructions or timing.
(btw I really like your Basic hacks!)
#3
Quote from: Prodatron on Yesterday at 21:06Is there any reason why you should know about these undocumented bits in the F-register beside to develop a 100% correct Z80 emulator?I trying to emulate the z80, I'm not planning to make another RVM either
I never understood why this was necessary to know. Does it have any advantages for making code better/faster/shorter? Does anyone have an example for this? Or is this just for fun (which includes detecting, if a Z80 emu is cool or not).
#4
Sounds like a good scheme.
Thanks!
Thanks!
#5
A
General Discussion - Introductions / Re: Interview with Dave Rogers
Last post by Anthony Flack - Today at 10:13While most people remember his music, for me it will always be The Scout Steps Out and especially Radzone. I love that game.
#6
If you want to do something along these lines, the memory arrangement I used:
Main code goes in bank 0.
Front/back buffers are in bank 2 and 3 at &8000 and &c000.
Clean buffer, compiled sprites, and any other code all swap in to bank 1 at &4000, so that you can copy from any of these banks into either screen buffer.
Main code goes in bank 0.
Front/back buffers are in bank 2 and 3 at &8000 and &c000.
Clean buffer, compiled sprites, and any other code all swap in to bank 1 at &4000, so that you can copy from any of these banks into either screen buffer.
#7
As a feedback, I'd say that it looks like you can't see s**t with the current camera and speed. Maybe the camera could be moved up a little or the speed reduced?
EDIT: I think it's the peculiar format of the video with margins. I suspect the movement would look normal in a normal video.
EDIT: I think it's the peculiar format of the video with margins. I suspect the movement would look normal in a normal video.
#8
Quote from: Fran123 on 15:51, 13 April 24I invented a steering wheel for the cpc. It would be connected through the expansion port. I have not implemented it but the scheme is very simple. It could be turned with different degrees and the steering wheel and brake would also have different degrees.It might be interesting to add support for it. even for the mouse interface. Thank you.
Quote from: Sykobee (Briggsy) on Yesterday at 11:55Looks great, are there any technical details how this fake mode 7 works in this game?Fixed sky area (6 chars), double buffer game area (13 chars), fixed car view area (6 chars), 32 width chars to optimize memory space for double buffer (not strictly for the maths) <---- SyX programmed me the interrupt function to use this configuration. Thanks SyX I owe you a beer
Line doubling? 32 char wide screen for optimal maths? Byte addressing, not nybble.
.The game area have 8 chars to draw mode 7 (calc 32 lines and i duplicate it to 64 lines) and 2 chars to background image.
Right now, the game runs at an average of 8/10 frames/sec (if you have to draw walls very close the framerate can drop quite a bit
). But I still have a lot to implement and it may change a little.To make fake mode 7 (Patent pending
) i have a table with precalculated data of the view (xy displacement of each visible line at that angle) and the game moves the player's position and calculates what color is drawn at that position in a loop.To make these calculations faster, the game uses a part of the tile map and transforms it into a little bitmap in runtime (1 track pixel, 1 byte) so as not to need to process the nibble or tile information in the loop.
Walls info is in the same tile pixel info. While the loop check the pixel of the floor it can detect the wall and save it to draw at the end. The wall drawing scale wall info pixels in runtime.
If you want more specific information, ask me whatever you want. Thank you.
Quote from: sigh on Yesterday at 15:41That is mighty impressive!
I would love to see the actual car you are driving to give it that FZero vibe.
I was also thinking how nice it would be to not make it an F1 game, but a PowerDrift type of game instead so that it would have hills, dips and jumps. I'm guessing that a lot more memory would need to be freed up, so it would probably need to be a mode 1 game?
Thank you sigh, unfortunately the engine is designed so that the ground is flat. It is drawn horizontally to make it faster. To do what you mention i would have to draw vertically and do more calculations, i guess it couldn't be done that quickly (or at least I don't know how to do it).
The graphics mode doesn't matter too much in memory for this game.
#9
General Discussion - Introductions / Re: Interview with Dave Rogers
Last post by asertus - Today at 09:05Quote from: Herman on Today at 07:44[...] Question: You worked almost exclusively for the Amstrad CPC and the ZX Spectrum. What did you find so attractive in the AY Chip? Were you never tempted to try the C64´s SID?
Rogers: Yes, I was very much aware at the time that the C64 had more powerful sound. The SID chip wasn't just slightly more powerful than the AY, it was MUCH more powerful.
However, I was more interested in the structure of the music than the sound of the chip. So I was quite happy to carry on with the AY.
I have to say that the sound of the SID chip, to my ears, is sometimes irritating and fatiguing, with all those fizzy FM-like harmonics.
It is important he says he focused on Amstrad's speaker and how the sound was in that speaker:
QuoteI liked everything about it, except for the small speaker. I could have connected bigger speakers, but I didn't, because I wanted to optimize the music for the built in speaker, which is what most people would hear it through. I tried to use frequencies and envelopes that would help overcome it's limitations.
