game.c

   1 #include <SDL2/SDL.h>
   2
   3 #include <assert.h>
   4 #include <stdbool.h>
   5 #include <math.h>
   6
   7 #include "game.h"
   8
   9 #define SPEED  0.00006
  10 #define ROTATE 0.00004
  11
  12 Player g_player[MAX_PLAYERS];
  13
  14 static void moveplayer(int id, float speed) {
  15         g_player[id].vx += speed * cos(g_player[id].r * 2 * M_PI);
  16         g_player[id].vy += speed * sin(g_player[id].r * 2 * M_PI);
  17 }
  18
  19 static void checkspacebound(float * a) {
  20         float x = *a;
  21         if(x < -1)
  22                 x = abs(x);
  23         else if(x > 1)
  24                 x = -x;
  25         *a = x;
  26 }
  27
  28 void g_player_set(unsigned int id, bool live, float x, float y, float r, float vx, float vy, float vr) {
  29         assert(id < MAX_PLAYERS);
  30         g_player[id] = (Player) {
  31                 .updated = true,
  32                 .live    = live,
  33                 .x       = x,
  34                 .y       = y,
  35                 .r       = r,
  36                 .vx      = vx,
  37                 .vy      = vy,
  38                 .vr      = vr,
  39         };
  40 }
  41
  42 void g_player_does(unsigned int id, DoesCode code) {
  43         assert(id < MAX_PLAYERS);
  44         g_player[id].updated = true;
  45         switch(code) {
  46         case DOES_UP:    moveplayer(id, SPEED); break;
  47         case DOES_DOWN:  moveplayer(id, -SPEED); break;
  48         case DOES_LEFT:  g_player[id].vr -= ROTATE; break;
  49         case DOES_RIGHT: g_player[id].vr += ROTATE; break;
  50         case DOES_FIRE:  break;
  51         }
  52 }
  53
  54 void g_update() {
  55         for(int i = 0; i < MAX_PLAYERS; i++) {
  56                 if(g_player[i].live) {
  57                         g_player[i].updated = true;
  58                         g_player[i].x += g_player[i].vx;
  59                         g_player[i].y += g_player[i].vy;
  60                         g_player[i].r += g_player[i].vr;
  61                         checkspacebound(&g_player[i].x);
  62                         checkspacebound(&g_player[i].y);
  63                 }
  64         }
  65 }