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/* event.c
*
* Event Handler
*
*
*/
#include <SDL/SDL.h>
#include <SDL/SDL_image.h>
#include <assert.h>
#include "client.h"
#include "glframe.h"
#include "platform.h"
#include "window.h"
#include "event.h"
extern int program_running;
/* an event handler struct that contains a table with function pointers */
static struct event_handler event_handler;
/* when user inputs NULL for tbl, generic functions get stubbed */
int event_handler_init(struct platform *plat, struct event_vtbl *tbl)
{
if (!plat)
return -1;
event_handler.p = plat;
if (tbl)
event_handler.funcs = *tbl;
else
{
memset(&event_handler.funcs, 0, sizeof(event_handler.funcs));
fprintf(stdout, "event: generic event handler will be provided\n");
}
/* predefined generic handlers that are automatically provided */
if (!event_handler.funcs.keydown)
event_handler.funcs.keydown = &event_keydown_gen;
if (!event_handler.funcs.windowresize)
event_handler.funcs.windowresize = &window_resize;
if (!event_handler.funcs.quit)
event_handler.funcs.quit = &event_quit_gen;
return 0;
}
/* process SDL events */
void sdl_process_events(void)
{
SDL_Event event;
SDLKey sym;
unsigned int *keys_held = event_handler.keys_held;
event_handler.key_held = 0;
while (SDL_PollEvent(&event))
{
sym = event.key.keysym.sym;
switch (event.type)
{
/* keyboard event */
case SDL_KEYUP:
{
/* reset the key to 0 */
keys_held[sym] = 0;
break;
}
case SDL_KEYDOWN:
{
keys_held[sym] = 1;
if (event_handler.funcs.keydown)
event_handler.funcs.keydown(&event.key.keysym);
break;
}
case SDL_VIDEORESIZE:
{
assert(event_handler.funcs.windowresize);
event_handler.funcs.windowresize(event.resize.w, event.resize.h);
break;
}
case SDL_QUIT:
{
assert(event_handler.funcs.quit);
event_handler.funcs.quit();
break;
}
default:
break;
}
}
/* below code has to be placed here, check for keys that are being constantly held */
if (keys_held[SDLK_w] || keys_held[SDLK_s] || keys_held[SDLK_a] ||
keys_held[SDLK_d] || keys_held[SDLK_UP] || keys_held[SDLK_DOWN] ||
keys_held[SDLK_LEFT] || keys_held[SDLK_RIGHT] || keys_held[SDLK_n] ||
keys_held[SDLK_m])
{
event_handler.key_held = !event_handler.key_held;
event_handler.funcs.keydown(NULL);
}
}
/* generic handler function, an exception is window_resize, it is declared
* in window.c */
void event_keydown_gen(SDL_keysym *keysym)
{
if (!keysym)
return;
switch (keysym->sym)
{
case SDLK_ESCAPE:
event_handler.funcs.quit();
break;
case SDLK_r:
glframe_reset(&(*event_handler.p).camera);
break;
default:
break;
}
}
void event_quit_gen(void)
{
program_running = 0;
}
/* here are the client event handler functions */
void event_keydown(SDL_keysym *keysym)
{
const unsigned int *keys_held = event_handler.keys_held;
struct platform *p = event_handler.p;
/* a flag is toggled on if the keys that we are interested in are being held */
if (event_handler.key_held)
{
if (keys_held[SDLK_w])
p->c->xrot -= 5.0f;
if (keys_held[SDLK_s])
p->c->xrot += 5.0f;
if (keys_held[SDLK_a])
p->c->yrot -= 5.0f;
if (keys_held[SDLK_d])
p->c->yrot += 5.0f;
if (keys_held[SDLK_UP])
glframe_move_forward(&p->camera, 0.05f);
if (keys_held[SDLK_DOWN])
glframe_move_forward(&p->camera, -0.05f);
if (keys_held[SDLK_LEFT])
glframe_rotate_local_y(&p->camera, 0.02f);
if (keys_held[SDLK_RIGHT])
glframe_rotate_local_y(&p->camera, -0.02f);
if (keys_held[SDLK_n])
glframe_rotate_local_x(&p->camera, 0.02f);
if (keys_held[SDLK_m])
glframe_rotate_local_x(&p->camera, -0.02f);
}
else
{
switch (keysym->sym)
{
case SDLK_ESCAPE:
program_running = 0;
break;
case SDLK_r:
glframe_reset(&(*event_handler.p).camera);
break;
case SDLK_w:
p->c->xrot -= 5.0f;
break;
case SDLK_s:
p->c->xrot += 5.0f;
break;
case SDLK_a:
p->c->yrot -= 5.0f;
break;
case SDLK_d:
p->c->yrot += 5.0f;
break;
case SDLK_UP:
glframe_move_forward(&p->camera, 0.5f);
break;
case SDLK_DOWN:
glframe_move_forward(&p->camera, -0.5f);
break;
case SDLK_LEFT:
glframe_rotate_local_y(&p->camera, 0.1f);
break;
case SDLK_RIGHT:
glframe_rotate_local_y(&p->camera, -0.1f);
break;
case SDLK_n:
glframe_rotate_local_x(&p->camera, 0.1f);
break;
case SDLK_m:
glframe_rotate_local_x(&p->camera, -0.1f);
break;
default:
break;
}
}
p->c->xrot = (GLfloat) ((const int) p->c->xrot % 360);
p->c->yrot = (GLfloat) ((const int) p->c->yrot % 360);
}
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