| 1 | /* |
| 2 | * Copyright (C) 2008 Patrik Gornicz, Gornicz_P (at) hotmail (dot) com. |
| 3 | * |
| 4 | * This program is free software: you can redistribute it and/or modify |
| 5 | * it under the terms of the GNU General Public License as published by |
| 6 | * the Free Software Foundation, either version 3 of the License, or |
| 7 | * (at your option) any later version. |
| 8 | * |
| 9 | * This program is distributed in the hope that it will be useful, |
| 10 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 11 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 12 | * GNU General Public License for more details. |
| 13 | * |
| 14 | * You should have received a copy of the GNU General Public License |
| 15 | * along with this program. If not, see <http://www.gnu.org/licenses/>. |
| 16 | */ |
| 17 | |
| 18 | #include <GL/gl.h> |
| 19 | #include <GL/glu.h> |
| 20 | #include <SDL/SDL.h> |
| 21 | |
| 22 | #include "debug.h" |
| 23 | #include "handleSignal.h" |
| 24 | |
| 25 | #include "game.h" |
| 26 | #include "ticks.h" |
| 27 | |
| 28 | #include "graphics/graphics.h" |
| 29 | #include "input/inputManager.h" |
| 30 | |
| 31 | /// ***** Private Method Headers ***** |
| 32 | |
| 33 | void init(); |
| 34 | |
| 35 | void sighandler( int sig ); |
| 36 | |
| 37 | void run(); |
| 38 | void clean(); |
| 39 | |
| 40 | void blockUpdate(); |
| 41 | void updateFPSCounters(); |
| 42 | |
| 43 | void handleInput(); |
| 44 | void update(float); |
| 45 | void draw(); |
| 46 | |
| 47 | /// ***** Private Variables ***** |
| 48 | |
| 49 | // variable used to determine if it is time to shutdown |
| 50 | bool is_Running; |
| 51 | |
| 52 | /* Values for the main game loop |
| 53 | * target_UPS := the amount of updates that is wanted in one second |
| 54 | * last_Update := stores the time of the last update |
| 55 | * update_Sum := used to determine the updates needs for this run |
| 56 | |
| 57 | * ups := updates per second for the last second |
| 58 | * fps := frames per second for the last second |
| 59 | * update_Count := counts this seconds updates |
| 60 | * draw_Count := counts this seconds draws |
| 61 | * last_Second := stores the time of the last second, used for ups and fps |
| 62 | */ |
| 63 | int target_UPS = 250; |
| 64 | long int last_Block_Update; |
| 65 | float update_Sum = 0; |
| 66 | |
| 67 | int ups, fps; |
| 68 | int update_Count, draw_Count; |
| 69 | long int last_Second; |
| 70 | |
| 71 | |
| 72 | /// ***** MAIN Method ***** |
| 73 | int main() |
| 74 | { |
| 75 | init(); |
| 76 | run(); |
| 77 | clean(); |
| 78 | return 0; |
| 79 | } |
| 80 | |
| 81 | /// ***** Initializers/Cleaners ***** |
| 82 | |
| 83 | void init() |
| 84 | { |
| 85 | installSignal(); |
| 86 | |
| 87 | graphics::init(); |
| 88 | |
| 89 | game::init(); |
| 90 | |
| 91 | input::init(); |
| 92 | |
| 93 | #ifdef DEBUGGING |
| 94 | cout << "Initialization Complete" << endl; |
| 95 | #endif |
| 96 | } |
| 97 | |
| 98 | void clean() |
| 99 | { |
| 100 | #ifdef DEBUGGING |
| 101 | cout << "Cleaning up" << endl; |
| 102 | #endif |
| 103 | |
| 104 | input::clean(); |
| 105 | |
| 106 | game::clean(); |
| 107 | |
| 108 | graphics::clean(); |
| 109 | } |
| 110 | |
| 111 | /// ***** Private Methods ***** |
| 112 | |
| 113 | void run() |
| 114 | { |
| 115 | is_Running = true; |
| 116 | last_Block_Update = tickCountMicro(); |
| 117 | last_Second = tickCountMicro(); |
| 118 | |
| 119 | while(is_Running) |
| 120 | { |
| 121 | blockUpdate(); |
| 122 | updateFPSCounters(); |
| 123 | draw(); |
| 124 | } |
| 125 | } |
| 126 | |
| 127 | void blockUpdate() |
| 128 | { |
| 129 | long int start = tickCountMicro(); |
| 130 | |
| 131 | // Calculate the updates that should be run for the next draw |
| 132 | update_Sum += (start - last_Block_Update) / (1000000 / (float)target_UPS); |
| 133 | |
| 134 | // insures the float to int cast is done once. |
| 135 | int iupdate_sum = (int)update_Sum; |
| 136 | |
| 137 | // TODO the main run loop needs to be tested and pruned |
| 138 | if (iupdate_sum > 0) |
| 139 | { |
| 140 | // Calculate a time step that spreads the updates out as much as possible |
| 141 | // used because really quick updates are nearly wasted |
| 142 | float time_step = ((float)(start - last_Block_Update)) / iupdate_sum; |
| 143 | |
| 144 | // run the updates |
| 145 | for (int i = 1; i <= iupdate_sum; i++) |
| 146 | { |
| 147 | handleInput(); |
| 148 | update(time_step*i / 1000); |
| 149 | } |
| 150 | // remove the updates that where run from the sum |
| 151 | update_Sum -= iupdate_sum; |
| 152 | last_Block_Update = tickCountMicro(); |
| 153 | } |
| 154 | } |
| 155 | |
| 156 | void updateFPSCounters() |
| 157 | { |
| 158 | // Check if a second has passed to recalculate UPS and FPS |
| 159 | if (tickCountMicro() - last_Second >= 1000000) |
| 160 | { |
| 161 | ups = update_Count; |
| 162 | fps = draw_Count; |
| 163 | update_Count = 0; |
| 164 | draw_Count = 0; |
| 165 | |
| 166 | last_Second = tickCountMicro(); |
| 167 | |
| 168 | #ifdef FPSUPS |
| 169 | cout << "ups:\t" << ups << endl; |
| 170 | cout << "fps:\t" << fps << endl; |
| 171 | #endif |
| 172 | } |
| 173 | } |
| 174 | |
| 175 | void handleInput() |
| 176 | { |
| 177 | input::update(); |
| 178 | |
| 179 | game::input(); |
| 180 | |
| 181 | if(input::wasReleased(SDLK_ESCAPE)) |
| 182 | is_Running = false; |
| 183 | } |
| 184 | |
| 185 | void update(float time_step) |
| 186 | { |
| 187 | update_Count++; |
| 188 | |
| 189 | game::update(time_step); |
| 190 | } |
| 191 | |
| 192 | void draw() |
| 193 | { |
| 194 | draw_Count++; |
| 195 | |
| 196 | game::draw(); |
| 197 | |
| 198 | SDL_GL_SwapBuffers(); |
| 199 | |
| 200 | glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT); |
| 201 | } |