JasonWoof Got questions, comments, patches, etc.? Contact Jason Woofenden
w00t! Finally rearranged the scroll equations so they make sense to me.
[vor.git] / main.c
diff --git a/main.c b/main.c
index db95bb4..c32feb3 100644 (file)
--- a/main.c
+++ b/main.c
  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
  */
 
+#include <argp.h>
+#include <math.h>
+#include <SDL/SDL.h>
+#include <SDL/SDL_image.h>
+#include <stdarg.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include "SFont.h"
+
 #ifdef DEBUG
 #include "debug.h"
 #endif
 
 #include "args.h"
+#include "common.h"
 #include "config.h"
+#include "dust.h"
 #include "file.h"
 #include "globals.h"
+#include "mt.h"
 #include "rocks.h"
 #include "score.h"
 #include "shape.h"
 #include "sound.h"
 
-#include <argp.h>
-#include <math.h>
-#include <SDL/SDL.h>
-#include <SDL/SDL_image.h>
-#include <stdarg.h>
-#include <stdio.h>
-#include <stdlib.h>
-#include <string.h>
-
-#include "SFont.h"
-
 // ************************************* VARS
 // SDL_Surface global variables
 SDL_Surface 
@@ -63,7 +66,6 @@ SFont_Font *g_font;
 // Structure global variables
 struct enginedots edot[MAXENGINEDOTS], *dotptr = edot;
 struct bangdots bdot[MAXBANGDOTS], *bdotptr = bdot;
-struct spacedot sdot[MAXSPACEDOTS];
 
 // Other global variables
 char topline[1024];
@@ -76,13 +78,19 @@ float shipx = XSIZE/2, shipy = YSIZE/2;     // X position, 0..XSIZE
 float shipdx = SCREENDXMIN, shipdy = 0.0;      // Change in X position per tick.
 float screendx = SCREENDXMIN, screendy = 0.0;
 float xscroll, yscroll;
-float framelen;  // this controls the speed of everything that moves.
+float back_dist;
+
+// all movement is based on t_frame.
+float t_frame;  // length of this frame (in ticks = 1/20th second)
+float s_frame;  // length of this frame (seconds)
+int ms_frame;   // length of this frame (milliseconds)
+int ms_end;     // end of this frame (milliseconds)
 
 float bangx, bangy, bangdx, bangdy;
 
-int nships,score,ticks_since_last,last_ticks;
+int nships,score;
 int gameover;
-int maneuver = 0;
+int jets = 0;
 
 float fadetimer = 0, faderate;
 
@@ -115,12 +123,9 @@ char *data_dir;
 extern char *optarg;
 extern int optind, opterr, optopt;
 
-// ************************************* FUNCS
+#define TO_TICKS(seconds) ((seconds)*20*opt_gamespeed)
 
-float
-rnd() {
-       return (float)random()/(float)RAND_MAX;
-}
+// ************************************* FUNCS
 
 void
 init_engine_dots() {
@@ -131,23 +136,8 @@ init_engine_dots() {
 }
 
 void
-init_space_dots() {
-       int i,b;
-       for(i = 0; i<MAXSPACEDOTS; i++) {
-               sdot[i].x = rnd()*(XSIZE-5);
-               sdot[i].y = rnd()*(YSIZE-5);
-               sdot[i].z = MAXDUSTDEPTH*sqrt(rnd());
-               b = (MAXDUSTDEPTH - sdot[i].z) * 255.0 / MAXDUSTDEPTH;
-               sdot[i].color = SDL_MapRGB(surf_screen->format, b, b, b);
-       }
-}
-
-void
-make_bang_dots(int xbang, int ybang, int dx, int dy, SDL_Surface *s, int power) {
-
-       // TODO - stop generating dots after a certain amount of time has passed, to cope with slower CPUs.
-       // TODO - generate and display dots in a circular buffer
-
+new_bang_dots(int xbang, int ybang, int dx, int dy, SDL_Surface *s, int power)
+{
        int x,y,endcount;
        Uint16 *rawpixel,c;
        double theta,r;
@@ -167,9 +157,9 @@ make_bang_dots(int xbang, int ybang, int dx, int dy, SDL_Surface *s, int power)
                                c = rawpixel[s->pitch/2*y + x];
                                if(c && c != s->format->colorkey) {
 
-                                       theta = rnd()*M_PI*2;
+                                       theta = frnd()*M_PI*2;
 
-                                       r = 1-(rnd()*rnd());
+                                       r = 1-(frnd()*frnd());
 
                                        bdot[bd2].dx = (power/50.0)*45.0*cos(theta)*r + dx;
                                        bdot[bd2].dy = (power/50.0)*45.0*sin(theta)*r + dy;
@@ -179,7 +169,7 @@ make_bang_dots(int xbang, int ybang, int dx, int dy, SDL_Surface *s, int power)
                                        // Replace the last few bang dots with the pixels from the exploding object
                                        bdot[bd2].c = (endcount>0)?c:0;
                                        bdot[bd2].life = 100;
-                                       bdot[bd2].decay = rnd()*3 + 1;
+                                       bdot[bd2].decay = frnd()*3 + 1;
                                        bdot[bd2].active = 1;
 
                                        bd2++;
@@ -224,8 +214,8 @@ draw_bang_dots(SDL_Surface *s) {
                        //last_i = i + 1;
                        rawpixel[(int)(s->pitch/2*(int)(bdot[i].y)) + (int)(bdot[i].x)] = bdot[i].c ? bdot[i].c : heatcolor[(int)(bdot[i].life*3)];
                        bdot[i].life -= bdot[i].decay;
-                       bdot[i].x += bdot[i].dx*framelen - xscroll;
-                       bdot[i].y += bdot[i].dy*framelen - yscroll;
+                       bdot[i].x += bdot[i].dx*t_frame - xscroll;
+                       bdot[i].y += bdot[i].dy*t_frame - yscroll;
 
                        if(bdot[i].life<0)
                        bdot[i].active = 0;
@@ -245,26 +235,6 @@ draw_bang_dots(SDL_Surface *s) {
 
 
 void
-draw_space_dots(SDL_Surface *s) {
-       int i;
-       Uint16 *rawpixel;
-       rawpixel = (Uint16 *) s->pixels;
-
-       for(i = 0; i<MAXSPACEDOTS; i++) {
-               if(sdot[i].y<0) {
-                       sdot[i].y = 0;
-               }
-               rawpixel[(int)(s->pitch/2*(int)sdot[i].y) + (int)(sdot[i].x)] = sdot[i].color;
-               sdot[i].x -= xscroll / (1.3 + sdot[i].z);
-               sdot[i].y -= yscroll / (1.3 + sdot[i].z);
-               if(sdot[i].y >= XSIZE) sdot[i].x -= XSIZE;
-               else if(sdot[i].x < 0) sdot[i].x = XSIZE-1;
-               if(sdot[i].y > YSIZE) sdot[i].y -= YSIZE;
-               else if(sdot[i].y < 0) sdot[i].y += YSIZE-1;
-       }
-}
-
-void
 draw_engine_dots(SDL_Surface *s) {
        int i;
        Uint16 *rawpixel;
@@ -272,9 +242,9 @@ draw_engine_dots(SDL_Surface *s) {
 
        for(i = 0; i<MAXENGINEDOTS; i++) {
                if(edot[i].active) {
-                       edot[i].x += edot[i].dx*framelen - xscroll;
-                       edot[i].y += edot[i].dy*framelen - yscroll;
-                       if((edot[i].life -= framelen*3)<0 || edot[i].y<0 || edot[i].y>YSIZE) {
+                       edot[i].x += edot[i].dx*t_frame - xscroll;
+                       edot[i].y += edot[i].dy*t_frame - yscroll;
+                       if((edot[i].life -= t_frame*3)<0 || edot[i].y<0 || edot[i].y>YSIZE) {
                                edot[i].active = 0;
                        } else if(edot[i].x<0 || edot[i].x>XSIZE) {
                                edot[i].active = 0;
@@ -289,84 +259,36 @@ draw_engine_dots(SDL_Surface *s) {
 }
 
 void
-create_engine_dots(int newdots) {
-       int i;
-       double theta,r,dx,dy;
-
-       if(!opt_tail_engine) return;
-
-       if(state == GAMEPLAY) {
-               for(i = 0; i<newdots*framelen; i++) {
-                       if(dotptr->active == 0) {
-                               theta = rnd()*M_PI*2;
-                               r = rnd();
-                               dx = cos(theta)*r;
-                               dy = sin(theta)*r;
-
-                               dotptr->active = 1;
-                               dotptr->x = shipx + surf_ship->w/2-14;
-                               dotptr->y = shipy + surf_ship->h/2 + (rnd()-0.5)*5-1;
-                               dotptr->dx = 10*(dx-1.5) + shipdx;
-                               dotptr->dy = 1*dy + shipdy;
-                               dotptr->life = 45 + rnd(1)*5;
-
-                               dotptr++;
-                               if(dotptr-edot >= MAXENGINEDOTS) {
-                                       dotptr = edot;
-                               }
-                       }
-               }
-       }
-}
-
-void
-create_engine_dots2(int newdots, int m) {
+new_engine_dots(int n, int dir) {
        int i;
-       double theta, theta2, dx, dy, adx, ady;
+       float a, r;  // angle, random length
+       float dx, dy;
+       float hx, hy; // half ship width/height.
+       static const int s[4] = { 2, 1, 0, 1 };
 
-       // Don't create fresh engine dots when
-       // the game is not being played and a demo is not beng shown
-       if(state != GAMEPLAY) return;
+       hx = surf_ship->w / 2;
+       hy = surf_ship->h / 2;
 
-       for(i = 0; i<newdots; i++) {
+       for(i = 0; i<n; i++) {
                if(dotptr->active == 0) {
-                       theta = rnd()*M_PI*2;
-                       theta2 = rnd()*M_PI*2;
-
-                       dx = cos(theta) * fabs(cos(theta2));
-                       dy = sin(theta) * fabs(cos(theta2));
-                       adx = fabs(dx);
-                       ady = fabs(dy);
-
+                       a = frnd()*M_PI + (dir-1)*M_PI_2;
+                       r = sin(frnd()*M_PI);
+                       dx = r * cos(a);
+                       dy = r * -sin(a);  // screen y is "backwards".
 
                        dotptr->active = 1;
-                       dotptr->x = shipx + surf_ship->w/2 + (rnd()-0.5)*3;
-                       dotptr->y = shipy + surf_ship->h/2 + (rnd()-0.5)*3;
-
-                       switch(m) {
-                               case 0:
-                                       dotptr->x -= 14;
-                                       dotptr->dx = -20*adx + shipdx;
-                                       dotptr->dy = 2*dy + shipdy;
-                                       dotptr->life = 60 * adx;
-                               break;
-                               case 1:
-                                       dotptr->dx = 2*dx + shipdx;
-                                       dotptr->dy = -20*ady + shipdy;
-                                       dotptr->life = 60 * ady;
-                               break;
-                               case 2:
-                                       dotptr->x += 14;
-                                       dotptr->dx = 20*adx + shipdx;
-                                       dotptr->dy = 2*dy + shipdy;
-                                       dotptr->life = 60 * adx;
-                               break;
-                               case 3:
-                                       dotptr->dx = 2*dx + shipdx;
-                                       dotptr->dy = 20*ady + shipdy;
-                                       dotptr->life = 60 * ady;
-                               break;
+                       dotptr->x = shipx + s[dir]*hx + (frnd()-0.5)*3;
+                       dotptr->y = shipy + s[(dir+1)&3]*hy + (frnd()-0.5)*3;
+                       if(dir&1) {
+                               dotptr->dx = shipdx + 2*dx;
+                               dotptr->dy = shipdy + 20*dy;
+                               dotptr->life = 60 * fabs(dy);
+                       } else {
+                               dotptr->dx = shipdx + 20*dx;
+                               dotptr->dy = shipdy + 2*dy;
+                               dotptr->life = 60 * fabs(dx);
                        }
+
                        dotptr++;
                        if(dotptr-edot >= MAXENGINEDOTS) {
                                dotptr = edot;
@@ -379,18 +301,17 @@ void
 drawdots(SDL_Surface *s) {
        int m;
 
-       // Create more engine dots comin' out da back
-       if(!gameover) create_engine_dots(200);
-
        // Create engine dots out the side we're moving from
        for(m = 0; m<4; m++) {
-               if(maneuver & 1<<m) { // 'maneuver' is a bit field
-                       create_engine_dots2(80,m);
+               if(jets & 1<<m) { // 'jets' is a bit field
+                       new_engine_dots(80,m);
                }
        }
 
+       move_dust();
+
        SDL_LockSurface(s);
-       draw_space_dots(s);
+       draw_dust(s);
        draw_engine_dots(s);
        draw_bang_dots(s);
        SDL_UnlockSurface(s);
@@ -424,7 +345,7 @@ init(void) {
                atexit(SDL_Quit);
        }
 
-       play_tune(0);
+       play_tune(TUNE_TITLE_PAGE);
 
        // Attempt to get the required video size
        flag = SDL_DOUBLEBUF | SDL_HWSURFACE;
@@ -473,7 +394,7 @@ init(void) {
        NULLERROR(surf_life = SDL_DisplayFormat(temp));
 
        init_engine_dots();
-       init_space_dots();
+       init_dust();
 
        init_rocks();
 
@@ -541,7 +462,7 @@ draw() {
 
                        dest.x = (XSIZE-surf_b_game->w)/2;
                        dest.y = (YSIZE-surf_b_game->h)/2-40;
-                       SDL_SetAlpha(surf_b_game, SDL_SRCALPHA, (int)(fadegame*(200 + 55*cos(fadetimer += framelen/1.0))));
+                       SDL_SetAlpha(surf_b_game, SDL_SRCALPHA, (int)(fadegame*(200 + 55*cos(fadetimer += t_frame/1.0))));
                        SDL_BlitSurface(surf_b_game,NULL,surf_screen,&dest);
 
                        dest.x = (XSIZE-surf_b_over->w)/2;
@@ -554,7 +475,7 @@ draw() {
 
                        dest.x = (XSIZE-surf_b_variations->w)/2 + cos(fadetimer/6.5)*10;
                        dest.y = (YSIZE/2-surf_b_variations->h)/2 + sin(fadetimer/5.0)*10;
-                       SDL_SetAlpha(surf_b_variations, SDL_SRCALPHA, (int)(200 + 55*sin(fadetimer += framelen/2.0)));
+                       SDL_SetAlpha(surf_b_variations, SDL_SRCALPHA, (int)(200 + 55*sin(fadetimer += t_frame/2.0)));
                        SDL_BlitSurface(surf_b_variations,NULL,surf_screen,&dest);
 
                        dest.x = (XSIZE-surf_b_on->w)/2 + cos((fadetimer + 1.0)/6.5)*10;
@@ -578,7 +499,7 @@ draw() {
                break;
 
                case HIGH_SCORE_ENTRY:
-                       play_tune(2);
+                       play_tune(TUNE_HIGH_SCORE_ENTRY);
                        if(!process_score_input()) {  // done inputting name
 
                                // Change state to briefly show high scores page
@@ -588,8 +509,7 @@ draw() {
                                // Write the high score table to the file
                                write_high_score_table();
                
-                               // Play the title page tune
-                               play_tune(0);
+                               play_tune(TUNE_TITLE_PAGE);
                        }
                // FALL THROUGH TO
                case HIGH_SCORE_DISPLAY:
@@ -605,17 +525,18 @@ draw() {
                bang = hit_rocks(shipx, shipy, &shipshape);
        }
 
-       ticks_since_last = SDL_GetTicks()-last_ticks;
-       last_ticks = SDL_GetTicks();
-       if(ticks_since_last>200 || ticks_since_last<0) {
+       ms_frame = SDL_GetTicks() - ms_end;
+       ms_end += ms_frame;
+       if(ms_frame>200 || ms_frame<0) {
                // We won't run at all below 5 frames per second.
-               framelen = 0;
+               // This also happens if we were paused, grr.
+               s_frame = 0;
+               ms_frame = 0;
        } else {
-               framelen = opt_gamespeed*ticks_since_last/50.0;
-               if(state == GAMEPLAY) {
-                       score += ticks_since_last;
-               }
+               s_frame = opt_gamespeed * ms_frame / 1000;
+               if(state == GAMEPLAY) score += ms_frame;
        }
+       t_frame = s_frame * 20;
 
        // Update the surface
        SDL_Flip(surf_screen);
@@ -634,12 +555,12 @@ gameloop() {
                if(!paused) {
                        // Count down the game loop timer, and change state when it gets to zero or less;
 
-                       if((state_timeout -= framelen*3) < 0) {
+                       if((state_timeout -= t_frame*3) < 0) {
                                switch(state) {
                                        case DEAD_PAUSE:
                                                // Create a new ship and start all over again
                                                state = GAMEPLAY;
-                                               play_tune(1);
+                                               play_tune(TUNE_GAMEPLAY);
                                                break;
                                        case GAME_OVER:
                                                if(new_high_score(score)) {
@@ -659,9 +580,6 @@ gameloop() {
                                                state_timeout = 500.0;
                                                break;
                                        case HIGH_SCORE_ENTRY:
-                                               // state = TITLE_PAGE;
-                                               // play_tune(1);
-                                               // state_timeout = 100.0;
                                                break;
                                        case TITLE_PAGE:
                                                state = HIGH_SCORE_DISPLAY;
@@ -690,38 +608,32 @@ gameloop() {
 
                        new_rocks();
 
-                       // FRICTION?
-                       if(opt_friction) {
-                               shipdx *= pow((double)0.9,(double)framelen);
-                               shipdy *= pow((double)0.9,(double)framelen);
-                       }
-
                        // INERTIA
-                       shipx += shipdx*framelen;
-                       shipy += shipdy*framelen;
+                       shipx += shipdx*t_frame;
+                       shipy += shipdy*t_frame;
 
                        // SCROLLING
-                       tmp = shipy - (YSIZE / 2);
-                       tmp += shipdy * 25;
-                       tmp /= -25;
-                       tmp = ((screendy * (framelen - 12)) + (tmp * framelen)) / 12;
-                       screendy = -tmp;
-                       tmp = shipx - (XSIZE / 3);
-                       tmp += shipdx * 25;
-                       tmp /= -25;
-                       tmp = ((screendx * (framelen - 12)) + (tmp * framelen)) / 12;
-                       screendx = -tmp;
-                       if(screendx < SCREENDXMIN) screendx=SCREENDXMIN;
-
-                       xscroll = screendx * framelen;
-                       yscroll = screendy * framelen;
+                       tmp = (shipy-YSCROLLTO)/25 + (shipdy-screendy);
+                       screendy += tmp * t_frame/12;
+                       tmp = (shipx-XSCROLLTO)/25 + (shipdx-screendx);
+                       screendx += tmp * t_frame/12;
+
+                       // taper off if we would hit the barrier in under 2 seconds.
+                       if(back_dist + (screendx - SCREENDXMIN)*TO_TICKS(2) < 0) {
+                               screendx = SCREENDXMIN - (back_dist/TO_TICKS(2));
+                       }
+
+                       xscroll = screendx * t_frame;
+                       yscroll = screendy * t_frame;
+                       back_dist += (screendx - SCREENDXMIN)*t_frame;
+                       if(opt_max_lead >= 0) back_dist = min(back_dist, opt_max_lead);
 
                        shipx -= xscroll;
                        shipy -= yscroll;
 
                        // move bang center
-                       bangx += bangdx*framelen - xscroll;
-                       bangy += bangdy*framelen - yscroll;
+                       bangx += bangdx*t_frame - xscroll;
+                       bangy += bangdy*t_frame - yscroll;
 
                        move_rocks();
 
@@ -729,23 +641,23 @@ gameloop() {
                        // BOUNCE X
                        if(shipx<0 || shipx>XSIZE-surf_ship->w) {
                                // BOUNCE from left and right wall
-                               shipx -= (shipdx-screendx)*framelen;
+                               shipx -= (shipdx-screendx)*t_frame;
                                shipdx = screendx - (shipdx-screendx)*opt_bounciness;
                        }
 
                        // BOUNCE Y
                        if(shipy<0 || shipy>YSIZE-surf_ship->h) {
                                // BOUNCE from top and bottom wall
-                               shipy -= (shipdy-screendy)*framelen;
+                               shipy -= (shipdy-screendy)*t_frame;
                                shipdy = screendy - (shipdy-screendy)*opt_bounciness;
                        }
 
 
                        if(draw() && state == GAMEPLAY) {
                                // Died
-                               play_sound(0); // Play the explosion sound
+                               play_sound(SOUND_BANG); // Play the explosion sound
                                bangx = shipx; bangy = shipy; bangdx = shipdx; bangdy = shipdy;
-                               make_bang_dots(shipx,shipy,shipdx,shipdy,surf_ship,30);
+                               new_bang_dots(shipx,shipy,shipdx,shipdy,surf_ship,30);
                                shipdx *= 0.5; shipdy *= 0.5;
                                if(shipdx < SCREENDXMIN) shipdx = SCREENDXMIN;
                                if(--nships <= 0) {
@@ -754,7 +666,7 @@ gameloop() {
                                        shipdx = 8; shipdy = 0;
                                        state_timeout = 200.0;
                                        fadetimer = 0.0;
-                                       faderate = framelen;
+                                       faderate = t_frame;
                                }
                                else {
                                        state = DEAD_PAUSE;
@@ -774,14 +686,14 @@ gameloop() {
                                score = 0;
 
                                state = GAMEPLAY;
-                               play_tune(1);
+                               play_tune(TUNE_GAMEPLAY);
 
                                gameover = 0;
                                shipx = XSIZE/2.2; shipy = YSIZE/2;
                                shipdx = screendx; shipdy = screendy;
                        }
 
-                       maneuver = 0;
+                       jets = 0;
                } else {
                        SDL_PumpEvents();
                        keystate = SDL_GetKeyState(NULL);
@@ -791,10 +703,10 @@ gameloop() {
                        if(!gameover) {
 
                                if(!paused) {
-                                       if(keystate[SDLK_UP] | keystate[SDLK_c])                { shipdy -= 1.5*framelen; maneuver |= 1<<3;}
-                                       if(keystate[SDLK_DOWN] | keystate[SDLK_t])              { shipdy += 1.5*framelen; maneuver |= 1<<1;}
-                                       if(keystate[SDLK_LEFT] | keystate[SDLK_h])              { shipdx -= 1.5*framelen; maneuver |= 1<<2;}
-                                       if(keystate[SDLK_RIGHT] | keystate[SDLK_n])             { shipdx += 1.5*framelen; maneuver |= 1;}
+                                       if(keystate[SDLK_LEFT]  | keystate[SDLK_h]) { shipdx -= 1.5*t_frame; jets |= 1<<0;}
+                                       if(keystate[SDLK_DOWN]  | keystate[SDLK_t]) { shipdy += 1.5*t_frame; jets |= 1<<1;}
+                                       if(keystate[SDLK_RIGHT] | keystate[SDLK_n]) { shipdx += 1.5*t_frame; jets |= 1<<2;}
+                                       if(keystate[SDLK_UP]    | keystate[SDLK_c]) { shipdy -= 1.5*t_frame; jets |= 1<<3;}
                                        if(keystate[SDLK_3])            { SDL_SaveBMP(surf_screen, "snapshot.bmp"); }
                                }
 
@@ -835,7 +747,6 @@ main(int argc, char **argv) {
                return 1;
        }
 
-       reset_rocks();
        gameloop();
 
        return 0;