Pure DOOM
Header only, no dependencies DOOM source port. Designed to run on any devices.
Primarily of interest to people that want to "run DOOM on their microwave".
LICENSE
See end of file for license information.
Main Features:
- Single header
- Pure-C, No includes dependencies: no stdlib, stdio, etc.
- Supports 32 bits and 64 bits
Other Features:
- Menu option to disable mouse move Forward/Backward
- Crosshair option
- Always-Run option
TODOs
- Custom resolution
- Remove exit and have update return 0 on quit. Add doom_get_exit_code()
- Implement Sockets and Multiplayer
- Print message when discovered a secret
Cool TODOs to have
- Rebindable keys
- Unlocked FPS
- Release mouse in menus and use it for clicking
- Wipe screen freezes menu
- Use floats instead of fixed_t
- French and german
- Full color mode (Don't use COLORMAPS, use full 24 bits RGB)
Usage
Call doom_init(), then call doom_update() every frame, or as often as you can. This will run DOOM, without any video, inputs, sounds or music.
#define DOOM_IMPLEMENTATION
#include "PureDOOM.h"
int main(int argc, char** argv)
{
doom_init(argc, argv, 0);
while (true)
{
doom_update();
}
}Enable features
Most standard headers are available on most platforms. Define these preprocessors to toggle these features.
DOOM_IMPLEMENT_PRINT. Allows printf, requires<stdio.h>DOOM_IMPLEMENT_MALLOC. Allows malloc/free, requires<stdlib.h>DOOM_IMPLEMENT_FILE_IO. Allows FILE, requires<stdio.h>DOOM_IMPLEMENT_GETTIME. Requires<sys/time.h>or<winsock.h>DOOM_IMPLEMENT_EXIT. Allows exit(), requires<stdlib.h>DOOM_IMPLEMENT_GETENV. Requires<stdlib.h>
If your microwave doesn't have these headers, you can override their default implementations:
void doom_set_print(doom_print_fn print_fn);
void doom_set_malloc(doom_malloc_fn malloc_fn, doom_free_fn free_fn);
void doom_set_file_io(doom_open_fn open_fn,
doom_close_fn close_fn,
doom_read_fn read_fn,
doom_write_fn write_fn,
doom_seek_fn seek_fn,
doom_tell_fn tell_fn,
doom_eof_fn eof_fn);
void doom_set_gettime(doom_gettime_fn gettime_fn);
void doom_set_exit(doom_exit_fn exit_fn);
void doom_set_getenv(doom_getenv_fn getenv_fn);Video
Every frame, after having called doom_update(), you can get the screen pixels with doom_get_framebuffer and display it as you please.
while (true)
{
doom_update();
uint8_t* framebuffer = doom_get_framebuffer(4 /* RGBA */);
// ... Display framebuffer
}Inputs
When you receive input events from your microwave touch pad, simply call one of the DOOM input events:
void doom_key_down(doom_key_t key);
void doom_key_up(doom_key_t key);
void doom_button_down(doom_button_t button);
void doom_button_up(doom_button_t button);
void doom_mouse_move(int delta_x, int delta_y);Sounds
Create a sound thread that outputs at 11025hz (DOOM_SAMPLERATE), 512 samples, 16 bits, stereo. Then in your sound callback, call doom_get_sound_buffer to update and get the current DOOM's sound output. Make sure to add synchronization primitives around this and doom_update if your sound loop is in a thread.
Here is a quick example using SDL audio callback:
void sdl_audio_callback(void* userdata, Uint8* stream, int len)
{
SDL_LockAudio();
int16_t* buffer = doom_get_sound_buffer(len);
SDL_UnlockAudio();
memcpy(stream, buffer, len);
}You can use different bitrate, but make sure to resample because DOOM will always be 11025hz, 512 samples, 16 bits, 2 channels. For a total for 2048 bytes per buffer.
Music
Set a timer in your application that runs at 140hz. In the timer's callback, tick DOOM's music as long as there are MIDI messages to send.
Here is an example using Window's MultiMedia to play MIDI events, using an SDL timer.
Uint32 tick_music(Uint32 interval, void *param)
{
uint32_t midi_msg;
SDL_LockAudio();
while (midi_msg = doom_tick_midi())
midiOutShortMsg(midi_out_handle, midi_msg);
SDL_UnlockAudio();
return 1000 / DOOM_MIDI_RATE /* 140 */;
}Change default settings
Default input setup in DOOM's source is not modern. It uses Arrows to move and ',' / '.' to strafe. You can call doom_set_default_int and doom_set_default_str to change them:
// Change default bindings to modern mapping
doom_set_default_int("key_up", DOOM_KEY_W);
doom_set_default_int("key_down", DOOM_KEY_S);
doom_set_default_int("key_strafeleft", DOOM_KEY_A);
doom_set_default_int("key_straferight", DOOM_KEY_D);
doom_set_default_int("key_use", DOOM_KEY_E);
doom_set_default_int("mouse_move", 0); // Mouse will not move forwardRefer to the defaults in m_misc.cpp for the complete list.
Working SDL Example
See the file src/sdl_example.c for a complete SDL example.
DOOM LICENSE
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you will not utilize, in any other manner, the Software in violation
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2. Permitted Uses. For educational purposes only, you, the
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