Playground for 3D rendering from scratch!
I know nothing about graphics, all I want is an array of pixels,
that I can update each frame with my own functions,
this is my attempt to make a 3D game like minecraft!
I have used gpt to help write the x11 or winapi parts of the code,
so I can just have my array of pixels that I update each frame.
I also used gpt to make the perlin noise function, as the maths for this is outside project scope,
but I thought it would be nice to have. Everything else is from scratch!
Work done so far:
- a fill function that takes 4 points, a colour, and fills it in
- a rotate and project function that takes an x y and z and rotates it about the camera using a global x and y rotation, and projects it by z
- texture mapping, which takes each cube face, and colours it pixel by pixel from a given texture
- simple cubicy collisions
- simple hotbar/hand with different blocks accesible by pressing 1-9
- back face culling, neighbour face culling
- placing and removing cubes within any chunk
- chunk system with dynamically saved chunk edits
- chunk generation from a given noise function
- tree/structure generation saved using the chunk edits
- fog at chunk borders
- day night cycle
- transparent water blocks that don't have collisions
Known issues:
- rendering issues when some points of a square have negative z values
Performance:
- from profiling I can see that the fill square function accounts for nearly half the total program instructions
- cache hits seem good, so the next step would be to come up with a faster fill square algorithm...
- I tried a few similar variations with fewer conditionals, but with little difference so I'm happy with this.
Next steps:
- I've come up with a way to make the sunlight better:
- store the sun as a point on a semicircle centred around a cube, with a large enough radius
- as the point moves around, calculate the distance from each face of the cube, to the point
- the difference between the closest face, and the furthest face represents a scale from completely dark, to completely bright
- use that scale to colour each face a certain brightness based on their distance to the sun
- I'd also love to try use sockets to make multiplayer from scratch - or just use enet...
- biomes sounds like a tough nut to crack so I'd love to try that some time too!
- Also I should really only rotate and project 8 coords of the cube, and do the texturing afterwards...
- Instead of reinventing the wheel for everything, I'd love to build this again in C from scratch, but do research into how it's actually done!
- From minimal googling since finishing the project, I would love to do:
- Z buffering, vertex buffering (don't rebuild everything every frame, buffer verticies of faces we can see, only update if chunk changes, or cube changes)
- Frustrum culling
To compile:
- linux:
- gcc -o DigMake.o -lX11 -lm -O3 -march=native ./linux-platform.c
- Windows:
- gcc -o DigMake.exe -O3 -march=native windows-platform.c -lgdi32 -lwinmm -mwindows
- Web:
- emcc main_web.c -O2 -lm -s ALLOW_MEMORY_GROWTH=1 -s EXPORTED_RUNTIME_METHODS='["ccall"]' -s EXPORTED_FUNCTIONS='["_main","_set_holding_mouse"]' -o DigMake.html
Or play right now (warning: may crash):
https://42henry.github.io/digmake-test/
Dev screenshots:
