src/particlesystem.cpp

   1 //  $Id$
   2 //
   3 //  SuperTux
   4 //  Copyright (C) 2004 Matthias Braun <matze@braunis.de>
   5 //
   6 //  This program is free software; you can redistribute it and/or
   7 //  modify it under the terms of the GNU General Public License
   8 //  as published by the Free Software Foundation; either version 2
   9 //  of the License, or (at your option) any later version.
  10 //
  11 //  This program is distributed in the hope that it will be useful,
  12 //  but WITHOUT ANY WARRANTY; without even the implied warranty of
  13 //  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14 //  GNU General Public License for more details.
  15 //
  16 //  You should have received a copy of the GNU General Public License
  17 //  along with this program; if not, write to the Free Software
  18 //  Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
  19 #include "particlesystem.h"
  20
  21 #include <iostream>
  22 #include <math.h>
  23 #include "globals.h"
  24 #include "scene.h"
  25
  26 ParticleSystem::ParticleSystem()
  27 {
  28     virtual_width = screen->w;
  29     virtual_height = screen->h;
  30 }
  31
  32 ParticleSystem::~ParticleSystem()
  33 {
  34     std::vector<Particle*>::iterator i;
  35     for(i = particles.begin(); i != particles.end(); ++i) {
  36         delete *i;
  37     }
  38 }
  39
  40 void ParticleSystem::draw(float scrollx, float scrolly, int layer)
  41 {
  42     std::vector<Particle*>::iterator i;
  43     for(i = particles.begin(); i != particles.end(); ++i) {
  44         Particle* particle = *i;
  45         if(particle->layer != layer)
  46             continue;
  47
  48         // remap x,y coordinates onto screencoordinates
  49         float x = fmodf(particle->x - scrollx, virtual_width);
  50         if(x < 0) x += virtual_width;
  51         float y = fmodf(particle->y - scrolly, virtual_height);
  52         if(y < 0) y += virtual_height;
  53         float xmax = fmodf(x + particle->texture->w, virtual_width);
  54         float ymax = fmodf(y + particle->texture->h, virtual_height);
  55
  56         // particle on screen
  57         if(x >= screen->w && xmax >= screen->w)
  58             continue;
  59         if(y >= screen->h && ymax >= screen->h)
  60             continue;
  61
  62         if(x > screen->w) x -= virtual_width;
  63         if(y > screen->h) y -= virtual_height;
  64         texture_draw(particle->texture, x, y);
  65     }
  66 }
  67
  68 SnowParticleSystem::SnowParticleSystem()
  69 {
  70     texture_load(&snowimages[0], datadir+"/images/shared/snow0.png", USE_ALPHA);
  71     texture_load(&snowimages[1], datadir+"/images/shared/snow1.png", USE_ALPHA);
  72     texture_load(&snowimages[2], datadir+"/images/shared/snow2.png", USE_ALPHA);
  73
  74     virtual_width = screen->w * 2;
  75
  76     // create some random snowflakes
  77     size_t snowflakecount = size_t(virtual_width/10.0);
  78     for(size_t i=0; i<snowflakecount; ++i) {
  79         SnowParticle* particle = new SnowParticle;
  80         particle->x = rand() % int(virtual_width);
  81         particle->y = rand() % screen->h;
  82         particle->layer = i % 2;
  83         int snowsize = rand() % 3;
  84         particle->texture = &snowimages[snowsize];
  85         particle->speed = 0.01 + snowsize/50.0 + (rand()%(int)gravity/15.0);
  86
  87         particles.push_back(particle);
  88     }
  89 }
  90
  91 SnowParticleSystem::~SnowParticleSystem()
  92 {
  93     for(int i=0;i<3;++i)
  94         texture_free(&snowimages[i]);
  95 }
  96
  97 void SnowParticleSystem::simulate(float elapsed_time)
  98 {
  99     std::vector<Particle*>::iterator i;
 100     for(i = particles.begin(); i != particles.end(); ++i) {
 101         SnowParticle* particle = (SnowParticle*) *i;
 102         particle->y += particle->speed * elapsed_time;
 103         if(particle->y > screen->h) {
 104             particle->y = 0;
 105             particle->x = rand() % int(virtual_width);
 106         }
 107     }
 108 }
 109
 110 CloudParticleSystem::CloudParticleSystem()
 111 {
 112     texture_load(&cloudimage, datadir + "/images/shared/cloud.png", USE_ALPHA);
 113
 114     virtual_width = 5000.0;
 115
 116     // create some random clouds
 117     for(size_t i=0; i<15; ++i) {
 118         CloudParticle* particle = new CloudParticle;
 119         particle->x = rand() % int(virtual_width);
 120         particle->y = rand() % int((float) screen->h * 0.3333);
 121         particle->layer = 0;
 122         particle->texture = &cloudimage;
 123         particle->speed = -float(250 + rand() % 200) / 1000.0;
 124
 125         particles.push_back(particle);
 126     }
 127 }
 128
 129 CloudParticleSystem::~CloudParticleSystem()
 130 {
 131     texture_free(&cloudimage);
 132 }
 133
 134 void CloudParticleSystem::simulate(float elapsed_time)
 135 {
 136     std::vector<Particle*>::iterator i;
 137     for(i = particles.begin(); i != particles.end(); ++i) {
 138         CloudParticle* particle = (CloudParticle*) *i;
 139         particle->x += particle->speed * elapsed_time;
 140     }
 141 }