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
  20 #include "particlesystem.h"
  21
  22 #include <iostream>
  23 #include <math.h>
  24 #include "globals.h"
  25 #include "lispreader.h"
  26 #include "lispwriter.h"
  27 #include "screen/drawing_context.h"
  28
  29 ParticleSystem::ParticleSystem()
  30 {
  31     virtual_width = screen->w;
  32     virtual_height = screen->h;
  33     layer = LAYER_BACKGROUND1;
  34 }
  35
  36 ParticleSystem::~ParticleSystem()
  37 {
  38     std::vector<Particle*>::iterator i;
  39     for(i = particles.begin(); i != particles.end(); ++i) {
  40         delete *i;
  41     }
  42 }
  43
  44 void ParticleSystem::draw(DrawingContext& context)
  45 {
  46   float scrollx = context.get_translation().x;
  47   float scrolly = context.get_translation().y;
  48
  49   context.push_transform();
  50   context.set_translation(Vector(0,0));
  51
  52     std::vector<Particle*>::iterator i;
  53     for(i = particles.begin(); i != particles.end(); ++i) {
  54         Particle* particle = *i;
  55
  56         // remap x,y coordinates onto screencoordinates
  57         Vector pos;
  58         pos.x = fmodf(particle->pos.x - scrollx, virtual_width);
  59         if(pos.x < 0) pos.x += virtual_width;
  60         pos.y = fmodf(particle->pos.y - scrolly, virtual_height);
  61         if(pos.y < 0) pos.y += virtual_height;
  62
  63         if(pos.x > screen->w) pos.x -= virtual_width;
  64         if(pos.y > screen->h) pos.y -= virtual_height;
  65         context.draw_surface(particle->texture, pos, layer);
  66     }
  67
  68     context.pop_transform();
  69 }
  70
  71 SnowParticleSystem::SnowParticleSystem()
  72 {
  73     snowimages[0] = new Surface(datadir+"/images/shared/snow0.png", USE_ALPHA);
  74     snowimages[1] = new Surface(datadir+"/images/shared/snow1.png", USE_ALPHA);
  75     snowimages[2] = new Surface(datadir+"/images/shared/snow2.png", USE_ALPHA);
  76
  77     virtual_width = screen->w * 2;
  78
  79     // create some random snowflakes
  80     size_t snowflakecount = size_t(virtual_width/10.0);
  81     for(size_t i=0; i<snowflakecount; ++i) {
  82         SnowParticle* particle = new SnowParticle;
  83         particle->pos.x = rand() % int(virtual_width);
  84         particle->pos.y = rand() % screen->h;
  85         int snowsize = rand() % 3;
  86         particle->texture = snowimages[snowsize];
  87         do {
  88             particle->speed = snowsize/60.0 + (float(rand()%10)/300.0);
  89         } while(particle->speed < 0.01);
  90
  91         particles.push_back(particle);
  92     }
  93 }
  94
  95 void
  96 SnowParticleSystem::parse(LispReader& reader)
  97 {
  98   reader.read_int("layer", layer);
  99 }
 100
 101 void
 102 SnowParticleSystem::write(LispWriter& writer)
 103 {
 104   writer.start_list("particles-snow");
 105   writer.write_int("layer", layer);
 106   writer.end_list("particles-snow");
 107 }
 108
 109 SnowParticleSystem::~SnowParticleSystem()
 110 {
 111   for(int i=0;i<3;++i)
 112     delete snowimages[i];
 113 }
 114
 115 void SnowParticleSystem::action(float elapsed_time)
 116 {
 117     std::vector<Particle*>::iterator i;
 118     for(i = particles.begin(); i != particles.end(); ++i) {
 119         SnowParticle* particle = (SnowParticle*) *i;
 120         particle->pos.y += particle->speed * elapsed_time;
 121         if(particle->pos.y > screen->h) {
 122             particle->pos.y = fmodf(particle->pos.y , virtual_height);
 123             particle->pos.x = rand() % int(virtual_width);
 124         }
 125     }
 126 }
 127
 128 CloudParticleSystem::CloudParticleSystem()
 129 {
 130     cloudimage = new Surface(datadir + "/images/shared/cloud.png", USE_ALPHA);
 131
 132     virtual_width = 2000.0;
 133
 134     // create some random clouds
 135     for(size_t i=0; i<15; ++i) {
 136         CloudParticle* particle = new CloudParticle;
 137         particle->pos.x = rand() % int(virtual_width);
 138         particle->pos.y = rand() % int(virtual_height);
 139         particle->texture = cloudimage;
 140         particle->speed = -float(250 + rand() % 200) / 1000.0;
 141
 142         particles.push_back(particle);
 143     }
 144 }
 145
 146 void
 147 CloudParticleSystem::parse(LispReader& reader)
 148 {
 149   reader.read_int("layer", layer);
 150 }
 151
 152 void
 153 CloudParticleSystem::write(LispWriter& writer)
 154 {
 155   writer.start_list("particles-clouds");
 156   writer.write_int("layer", layer);
 157   writer.end_list("particles-clouds");
 158 }
 159
 160 CloudParticleSystem::~CloudParticleSystem()
 161 {
 162   delete cloudimage;
 163 }
 164
 165 void CloudParticleSystem::action(float elapsed_time)
 166 {
 167     std::vector<Particle*>::iterator i;
 168     for(i = particles.begin(); i != particles.end(); ++i) {
 169         CloudParticle* particle = (CloudParticle*) *i;
 170         particle->pos.x += particle->speed * elapsed_time;
 171     }
 172 }