diff options
author | Vito Caputo <vcaputo@gnugeneration.com> | 2017-01-18 19:12:41 -0800 |
---|---|---|
committer | GitHub <noreply@github.com> | 2017-01-18 19:12:41 -0800 |
commit | 467137113c8b3d6bcb73ecff8c76f23793f25cb7 (patch) | |
tree | ecf3064d6587ec875d5c021d46d44855dc814212 /src/modules/stars/starslib.c | |
parent | ee2073d4e411555aba878277131b56f7eb562c84 (diff) | |
parent | 404a356b2b22a134aea151145d1baabf253ee491 (diff) |
Merge build system cleanups
- Move source to src/ subdir
- Use $(top_srcdir)/src instead of ../../
Diffstat (limited to 'src/modules/stars/starslib.c')
-rw-r--r-- | src/modules/stars/starslib.c | 133 |
1 files changed, 133 insertions, 0 deletions
diff --git a/src/modules/stars/starslib.c b/src/modules/stars/starslib.c new file mode 100644 index 0000000..9d43062 --- /dev/null +++ b/src/modules/stars/starslib.c @@ -0,0 +1,133 @@ +/* + * a starfield simulation library from: https://github.com/ph1l/stars + * Copyright 2014 Philip J. Freeman <elektron@halo.nu> + */ + +#include <stdlib.h> +#ifdef DEBUG +#include <stdio.h> +#endif +#include "starslib.h" + +struct points +{ + int x, y, z; + struct points *next; +}; + +void new_universe( struct universe** u, int width, int height, int depth ) +{ + *u = malloc(sizeof(struct universe)); + + (*u)->width = width; + (*u)->height = height; + (*u)->depth = depth; + + (*u)->iterator = NULL; + (*u)->points = NULL; + #ifdef DEBUG + printf("NEW UNIVERSE: %lx: (%i,%i,%i)\n", (long unsigned int )(*u), (*u)->width, (*u)->height, (*u)->depth); + #endif + + return; +} + +void new_point( struct universe* u ) +{ + + struct points* p_ptr = malloc(sizeof(struct points)); + + p_ptr->x = (rand()%u->width - (u->width/2)) * u->depth; + p_ptr->y = (rand()%u->height - (u->height/2)) * u->depth; + p_ptr->z = u->depth; + + p_ptr->next = u->points; + u->points = p_ptr; + #ifdef DEBUG + printf("NEW POINT: %lx: (%i,%i,%i) next=%lx\n", (long unsigned int )p_ptr, p_ptr->x, p_ptr->y, p_ptr->z, (long unsigned int) p_ptr->next); + #endif + + return; +} + +void kill_point( struct universe* universe, struct points* to_kill ) +{ + + struct points *p_ptr, *last_ptr = NULL; + + + for ( p_ptr = universe->points; p_ptr != NULL; p_ptr = p_ptr->next) + { + if (p_ptr == to_kill) + { + #ifdef DEBUG + printf("KILL POINT: %lx: (%i,%i,%i).\n", (long unsigned int )p_ptr, p_ptr->x, p_ptr->y, p_ptr->z); + #endif + if (last_ptr == NULL) + { + universe->points = p_ptr->next; + } else { + last_ptr->next = p_ptr->next; + } + free(p_ptr); + } else { + last_ptr = p_ptr; + } + } + #ifdef DEBUG + printf("KILL POINT: %lx\n", (long unsigned int )p_ptr); + #endif + return; +} + +int process_point( struct universe *u, struct return_point *rp ) +{ + + if ( u->iterator == NULL ) { + if (u->points == NULL){ + return 0; + } else { + u->iterator = u->points; + } + } + + if ( u->iterator->z == 0 ){ + // Delete point that has reached us. + struct points *tmp = u->iterator; + u->iterator = u->iterator->next; + kill_point( u, tmp ); + return(-1); + } else { + // Plot the point + int x, y; + x = u->iterator->x / u->iterator->z; + y = u->iterator->y / u->iterator->z; + if ( abs(x) >= u->width/2 || abs(y) >= u->height/2 ){ + // Delete point that is off screen + struct points *tmp = u->iterator; + u->iterator = u->iterator->next; + kill_point( u, tmp ); + if ( u->iterator == NULL ) { + return(0); + } else { + return(-1); + } + } else { + int m = OPACITY_MAX*((u->depth-u->iterator->z)*4)/u->depth; + if ( m>OPACITY_MAX ){ m=OPACITY_MAX; } + u->iterator->z = u->iterator->z - 1; + #ifdef DEBUG + printf("RETURN POINT: %lx\n", (long unsigned int )u->iterator); + #endif + u->iterator = u->iterator->next; + rp->x = x; + rp->y = y; + rp->opacity = m; + if ( u->iterator == NULL ) { + return(0); + } else { + return(1); + } + } + } +} |