mirror of
https://git.coom.tech/drummyfish/raycastlib.git
synced 2024-11-21 20:29:59 +01:00
104 lines
No EOL
4.6 KiB
Markdown
104 lines
No EOL
4.6 KiB
Markdown
# raycastlib
|
|
|
|
Ray casting library for (not only) limited-resource computers.
|
|
|
|
If you like this, you may also like my similar project: [small3dlib](https://gitlab.com/drummyfish/small3dlib).
|
|
|
|
eye-candy previews
|
|
------------------
|
|
|
|
Pokitto (32bit embedded console, 48 MHz, 36 kB RAM):
|
|
|
|
|
|
|
|
|
|
|
|
SDL (PC):
|
|
|
|
|
|
|
|
Arduboy (8bit Arduino console, 16 MHz, 2.5 kB RAM):
|
|
|
|
|
|
|
|
|
|
terminal:
|
|
|
|
|
|
|
|
Gamebuino META (Arduino 32bit console, 48 MHz, 32 kB RAM):
|
|
|
|
|
|
|
|
features
|
|
--------
|
|
|
|
- Very **fast, small and efficient**.
|
|
- Uses **only integer math** (32bit). The tiny version should only require 16bit, but isn't completed.
|
|
- **No dependencies** (uses only stdint standard library), extremely portable.
|
|
- **Single header**, KISS.
|
|
- Advanced rendering of **variable height floor and ceiling**.
|
|
- **Textured walls and floor**.
|
|
- **Depth information** (e.g. for fog or z-buffer rendering).
|
|
- **Camera shearing** (looking up/down).
|
|
- Camera movement with **collisions**.
|
|
- Partial support for **opening door**.
|
|
- **Pure C99**, tested to run as C++ as well.
|
|
- Optional framework **functions that handle the whole rendering**.
|
|
- Still **flexible** -- pixels are left for you to draw in any way you want.
|
|
- **Tested on multiple platforms** (PC, Arduboy, Pokitto, Gamebuino META).
|
|
- **Many compile-time options** to tune the performance vs quality.
|
|
- **Well commented** and formatted code.
|
|
- Completely **free of legal restrictions**, do literally anything you want.
|
|
|
|
**NOTE**: Backwards compatibility isn't a goal of this libraray. It is meant to
|
|
be an as-is set of tools that the users is welcome to adjust for their
|
|
specific project. So new features will be preferred to keeping the same
|
|
interface.
|
|
|
|
how to use
|
|
----------
|
|
|
|
For start take a look at the [testTerminal.c](https://gitlab.com/drummyfish/raycastlib/blob/master/programs/testTerminal.c) program.
|
|
It is only a little bit more complex than a simple hello world.
|
|
|
|
For more examples see the other files, plus my [Pokitto demos](https://gitlab.com/drummyfish/Pokitto-Raycasting) repository,
|
|
which contains some better documented example code, including a [very simple hello world](https://gitlab.com/drummyfish/Pokitto-Raycasting/blob/master/helloRay.cpp).
|
|
|
|
The basic philosophy is:
|
|
|
|
- The library implements only a rendering back-end, it doesn't permorm any drawing to the actual screen,
|
|
hence there is no dependency on any library such as OpenGL or SDL. It just calls your front-end function
|
|
and tells you which pixels you should write. How you do it is up to you.
|
|
- Before including the header, define `RCL_PIXEL_FUNCTION` to the name of a function you will use to
|
|
draw pixels. It is basically a fragment/pixel shader function that the library will call. You will
|
|
be passed info about the pixel and can decide what to do with it, so you can process it, discard it,
|
|
or simply write it to the screen.
|
|
- Call `RCL_renderSimple` or `RCL_renderComplex` to perform the frame rendering. This will cause the
|
|
library to start calling the `RCL_PIXEL_FUNCTION` in order to draw the frame. You can optionally write
|
|
a similar function of your own using the more low-level functions which are also provided.
|
|
- The library gets info about the world (such as floor or ceiling height) via *array* functions
|
|
(`RCL_ArrayFunction` type) -- functions that take *x* and *y* coordinates of a square and return given
|
|
information. This way you are free to not only fetch the map data from an array, but also generate
|
|
the world procedurally if that is what you want.
|
|
- Fixed point arithmetics is used as a principle, but there is no abstraction above it, everything is simply
|
|
an integer (`RCL_Unit` type). The space is considered to be a dense grid, where each world square
|
|
has a side length of `RCL_UNITS_PER_SQUARE` units. Numbers are normalized by this constant, so e.g.
|
|
the sin function returns a value from `-RCL_UNITS_PER_SQUARE` to `RCL_UNITS_PER_SQUARE`.
|
|
|
|
TODO
|
|
----
|
|
|
|
- Transparency (conditional ray passing through).
|
|
- Doors in the middle of squares.
|
|
- Rolling doors for `RCL_renderComplex`.
|
|
- Possibly merge all rendering functions into one.
|
|
|
|
license
|
|
-------
|
|
|
|
Everything is CC0 1.0 + a waiver of all other IP rights (including patents). The art used in demos is either my own released nder CC0 or someone else's released under CC0.
|
|
|
|
Please support free software and free culture by using free licenses and/or waivers.
|
|
|
|
If you'd like to support me or just read something about me and my projects, visit my site: [www.tastyfish.cz](http://www.tastyfish.cz/). |