Search found 101 matches

by Lucradan
Wed Feb 19, 2020 9:43 am
Forum: NES Graphics
Topic: Hiring Pixel Artist - Tips / Standards ?
Replies: 1
Views: 1030

Hiring Pixel Artist - Tips / Standards ?

I want to start outsourcing some of the pixel art I need done for a few my homebrews. I don't want to waste an artist's time, nor do I want to waste my money. What tips could you provide to best make the transaction easier? Do you have any lessons learned from previous experiences hiring pixel artis...
by Lucradan
Tue Feb 18, 2020 10:17 am
Forum: NESdev
Topic: Image Parser
Replies: 2
Views: 2433

Image Parser

I've uploaded a tool I made to help me convert image files into CHR, palette, and sprite files. https://github.com/Lucradan/ImageParser This allows a user to 1. Import an image 2. Edit its palette and recolor it 3. Place and move it on the screen (256x240) 4. Assign Background and Sprite Layer Palet...
by Lucradan
Tue Dec 03, 2019 9:42 am
Forum: NESdev
Topic: Tools and Code Repository
Replies: 3
Views: 2112

Tools and Code Repository

I'd like to share some tools I've created and some ASM6 subroutines. Any recommendations on how I might be able to do this? Specifically, places where I could submit and host.
by Lucradan
Wed Nov 06, 2019 2:13 pm
Forum: NESdev
Topic: FCEUX + Midframe Palette Swap
Replies: 22
Views: 5410

Re: FCEUX + Midframe Palette Swap

Thank you everyone! You're AWESOME! I got it the IRQ handlers fixed and timed perfectly with Mesen. It takes 24 scanlines to change all the palettes. That's 3 lines per palette: 1 line to change the colors during hblank, one line to reset the scroll, and one line to relatch the IRQ (done outside the...
by Lucradan
Wed Nov 06, 2019 11:24 am
Forum: NESdev
Topic: Updated random number generator (efficient 8-step LFSRs)
Replies: 7
Views: 4753

Re: Updated random number generator (efficient 8-step LFSRs)

lidnariq wrote:???
See the code here. They do a great job of explaining the LFSR

https://codebase64.org/doku.php?id=base ... 8-bit_prng

The "tuning parameter" is the value in the EOR command.
by Lucradan
Wed Nov 06, 2019 7:52 am
Forum: NESdev
Topic: Updated random number generator (efficient 8-step LFSRs)
Replies: 7
Views: 4753

Re: Updated random number generator (efficient 8-step LFSRs)

Most PRNGs (including LFSRs) work on the same idea of a moving along a fixed Hamiltonian cycle. Depending on the tuning parameters, LFSRs work on 1 of 16 different cycles. If you want the fastest PRNG, just create your own random permutation of the numbers 0 to 255 and use it as a look up table. It'...
by Lucradan
Wed Nov 06, 2019 12:06 am
Forum: NESdev
Topic: FCEUX + Midframe Palette Swap
Replies: 22
Views: 5410

Re: FCEUX + Midframe Palette Swap

nmi_handler: ; point vector $FFFA here inc nmis rti ppu_vsync: lda nmis @loop: cmp nmis beq @loop rts This is what I ended up doing. I already had the frame counter in the NMI. The only warning I see with this is if I trigger an IRQ during this wait loop. That IRQ must restore the accumulator befor...
by Lucradan
Tue Nov 05, 2019 8:19 pm
Forum: NESdev
Topic: FCEUX + Midframe Palette Swap
Replies: 22
Views: 5410

Re: FCEUX + Midframe Palette Swap

One alternative would be to point your IRQ vector to RAM, so you could select different handlers without any delays whatsoever (always make sure no IRQs fire while you're changing the address, or the program might crash). Could you clarify on how to do this properly? I'm not getting it. If I point ...
by Lucradan
Tue Nov 05, 2019 5:53 pm
Forum: NESdev
Topic: FCEUX + Midframe Palette Swap
Replies: 22
Views: 5410

Re: FCEUX + Midframe Palette Swap

I think that sounds like a plan. I'll check out Mesen when I get home. I THINK I might know one culprit that could me causing the intermittent flickering. I have the wrong "Wait for NMI" code in my main loops. I used the same BIT status check loop as I did in my RESET code. I should have been using ...
by Lucradan
Tue Nov 05, 2019 4:13 pm
Forum: NESdev
Topic: FCEUX + Midframe Palette Swap
Replies: 22
Views: 5410

Re: FCEUX + Midframe Palette Swap

UPDATE! I've made some fixes to the IRQ handler and simplified it by reducing the palette change to a single color (for now). This made the "gray line" problem to go away! LBL.BATTLE.PaletteChangeIRQ: STA IRQDISABLE LDX #$03 ; <-------- Low BYTE of PPU Palette LDY BUF.PALETTE.IRQ+12 ;Wait until next...
by Lucradan
Tue Nov 05, 2019 2:16 pm
Forum: NESdev
Topic: FCEUX + Midframe Palette Swap
Replies: 22
Views: 5410

Re: FCEUX + Midframe Palette Swap

The IRQ handler ends with a JMP and not an RTI? That's probably not what you want if this is the direct handler pointed to by the IRQ vector. Here is my IRQ handler. I just do an indirect jump to the value put in the pointer PTR.IRQJUMP which can change based on what I need to do with the IRQ (bank...
by Lucradan
Tue Nov 05, 2019 12:03 pm
Forum: NESdev
Topic: FCEUX + Midframe Palette Swap
Replies: 22
Views: 5410

Re: FCEUX + Midframe Palette Swap

I've though I'd followed the resources, but I must be missing something. Here is my IRQ so far: LBL.BATTLE.PaletteChangeIRQ: STA IRQDISABLE ; Disable Rendering LDX #$00 STX PPUMASK ; Resets the PPU address BIT PPUSTATUS ; Sets the PPU Address High Byte LDA #$3F STA PPUADDR ; Sets the PPU Address Low...
by Lucradan
Tue Nov 05, 2019 7:46 am
Forum: NESdev
Topic: FCEUX + Midframe Palette Swap
Replies: 22
Views: 5410

FCEUX + Midframe Palette Swap

Today, I'm going to try and tackle the dreaded midframe palette swap techniques described here https://forums.nesdev.com/viewtopic.php?f=2&t=13188 I have more than enough empty scanlines to pull this off so I'm not too worried. Was FCEUX ever updated so these effects can be emulated, or is there ano...
by Lucradan
Tue Oct 29, 2019 6:33 am
Forum: Newbie Help Center
Topic: RPG Advice
Replies: 3
Views: 5245

Re: RPG Advice

Those are great resources, thank you! I played around with some of the numbers over the last few days and think I have a good idea of how I should proceed. I'm going to try and leave as much flexibility as I can in many of the game mechanisms now to allow for more tuning options later. Lookup tables...
by Lucradan
Mon Oct 28, 2019 4:37 pm
Forum: Newbie Help Center
Topic: RPG Advice
Replies: 3
Views: 5245

RPG Advice

I'm working on a Final Fantasy style RPG. I've found a very detailed game mechanics breakdown which has been a great baseline on how things could be done: https://gamefaqs.gamespot.com/nes/522595-final-fantasy/faqs/57009 I'm looking for other insight, resources, or lessons learned in making these ty...