Raycaster bugs

[plush hemlock]

Hi :)
(I don't know if this is the right place to ask this)

I've been making a small raycaster with C recently. but there is a really annoying bug I'm facing.
(you can see it in the video)

I checked my DDA render() function many times but i couldn't find any bugs.

If you have enough experience in this topic, help would be really appreciated :)

Full Code: https://github.com/proh14/pdoom (sorry for the un-clean code i was frustrated so i kept everything in a single file and wrote some dirty code 😢)
Lodev article on raycasters: https://lodev.org/cgtutor/raycasting.html
(Its easy to build just get sdl3 and build it with make)

[lunar sundial]

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[untold coral]

Maybe change:

hit = map[mappos.x][mappos.y];

to first y then x?

Also implement screen clearing

You just leave alot of junk pixels from the frame before

memset(state.pixels, 0x00, WINDOW_WIDTH * WINDOW_HEIGHT * sizeof(uint32_t));

That should help a bit

[plush hemlock]

oh i thought i had the memset thing before...i removed it when i was kind of brute forcing different solutions

it gives a really simillar bug with the pixels kind of staying after each movment

im worried it might be the way i use sdl????

[opaque socket]

no

its your code not sdl

your rendering sequence is just wrong. the further away wall should be rendered first

or technically printed on the screen first.

or render the first wall that the ray hits. which is probably the more correct way

[plush hemlock]

thank you for your response

can you please show me how my rendering logic is wrong so i can fix it?

[lunar sundial]

@plush hemlock Has your question been resolved? If so, type !solved :)

[plush hemlock]

Never mind!

I fixed it

it was a sdl issue

i switched to using SDL_TEXTUREACCESS_STREAMING

and SDL_LockTexture and SDL_UnlockLockTexture

!solved