/* Copyright (C) 1996-2001 Id Software, Inc. Copyright (C) 2002-2009 John Fitzgibbons and others This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later version. This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with this program; if not, write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */ //gl_fog.c -- global and volumetric fog #ifdef HAVE_CONFIG_H # include "config.h" #endif static __attribute__ ((used)) const char rcsid[] = "$Id$"; #ifdef HAVE_STRING_H # include #endif #ifdef HAVE_STRINGS_H # include #endif #include "QF/cmd.h" #include "QF/qfplist.h" #include "QF/render.h" #include "QF/sys.h" #include "QF/GL/defines.h" #include "QF/GL/funcs.h" #include "compat.h" #include "r_shared.h" //============================================================================== // // GLOBAL FOG // //============================================================================== static float fog_density; static float fog_red; static float fog_green; static float fog_blue; static float old_density; static float old_red; static float old_green; static float old_blue; static float fade_time; //duration of fade static float fade_done; //time when fade will be done /* Fog_Update update internal variables */ void Fog_Update (float density, float red, float green, float blue, float time) { //save previous settings for fade if (time > 0) { //check for a fade in progress if (fade_done > r_realtime) { float f; f = (fade_done - r_realtime) / fade_time; old_density = f * old_density + (1.0 - f) * fog_density; old_red = f * old_red + (1.0 - f) * fog_red; old_green = f * old_green + (1.0 - f) * fog_green; old_blue = f * old_blue + (1.0 - f) * fog_blue; } else { old_density = fog_density; old_red = fog_red; old_green = fog_green; old_blue = fog_blue; } } fog_density = density; fog_red = red; fog_green = green; fog_blue = blue; fade_time = time; fade_done = r_realtime + time; } /* Fog_FogCommand_f handle the 'fog' console command */ static void Fog_FogCommand_f (void) { switch (Cmd_Argc ()) { default: case 1: Sys_Printf ("usage:\n"); Sys_Printf (" fog \n"); Sys_Printf (" fog \n"); Sys_Printf (" fog \n"); Sys_Printf ("current values:\n"); Sys_Printf (" \"density\" is \"%f\"\n", fog_density); Sys_Printf (" \"red\" is \"%f\"\n", fog_red); Sys_Printf (" \"green\" is \"%f\"\n", fog_green); Sys_Printf (" \"blue\" is \"%f\"\n", fog_blue); break; case 2: Fog_Update (max (0.0, atof (Cmd_Argv (1))), fog_red, fog_green, fog_blue, 0.0); break; case 3: //TEST Fog_Update (max (0.0, atof (Cmd_Argv (1))), fog_red, fog_green, fog_blue, atof (Cmd_Argv (2))); break; case 4: Fog_Update (fog_density, bound (0.0, atof (Cmd_Argv (1)), 1.0), bound (0.0, atof (Cmd_Argv (2)), 1.0), bound (0.0, atof (Cmd_Argv (3)), 1.0), 0.0); break; case 5: Fog_Update (max (0.0, atof (Cmd_Argv (1))), bound (0.0, atof (Cmd_Argv (2)), 1.0), bound (0.0, atof (Cmd_Argv (3)), 1.0), bound (0.0, atof (Cmd_Argv (4)), 1.0), 0.0); break; case 6: //TEST Fog_Update (max (0.0, atof (Cmd_Argv (1))), bound (0.0, atof (Cmd_Argv (2)), 1.0), bound (0.0, atof (Cmd_Argv (3)), 1.0), bound (0.0, atof (Cmd_Argv (4)), 1.0), atof (Cmd_Argv (5))); break; } } /* Fog_ParseWorldspawn called at map load */ void Fog_ParseWorldspawn (plitem_t *worldspawn) { plitem_t *fog; const char *value; //initially no fog fog_density = 0.0; old_density = 0.0; fade_time = 0.0; fade_done = 0.0; if (!worldspawn) return; // error if ((fog = PL_ObjectForKey (worldspawn, "fog")) && (value = PL_String (fog))) { sscanf (value, "%f %f %f %f", &fog_density, &fog_red, &fog_green, &fog_blue); } } /* Fog_GetColor calculates fog color for this frame, taking into account fade times */ float * Fog_GetColor (void) { static float c[4]; float f; int i; if (fade_done > r_realtime) { f = (fade_done - r_realtime) / fade_time; c[0] = f * old_red + (1.0 - f) * fog_red; c[1] = f * old_green + (1.0 - f) * fog_green; c[2] = f * old_blue + (1.0 - f) * fog_blue; c[3] = 1.0; } else { c[0] = fog_red; c[1] = fog_green; c[2] = fog_blue; c[3] = 1.0; } //find closest 24-bit RGB value, so solid-colored sky can match the fog //perfectly for (i = 0; i < 3; i++) c[i] = (float) (rint (c[i] * 255)) / 255.0f; return c; } /* Fog_GetDensity returns current density of fog */ float Fog_GetDensity (void) { float f; if (fade_done > r_realtime) { f = (fade_done - r_realtime) / fade_time; return f * old_density + (1.0 - f) * fog_density; } else { return fog_density; } } /* Fog_SetupFrame called at the beginning of each frame */ void Fog_SetupFrame (void) { qfglFogfv (GL_FOG_COLOR, Fog_GetColor ()); qfglFogf (GL_FOG_DENSITY, Fog_GetDensity () / 64.0); } /* Fog_EnableGFog called before drawing stuff that should be fogged */ void Fog_EnableGFog (void) { if (Fog_GetDensity () > 0) qfglEnable (GL_FOG); } /* Fog_DisableGFog called after drawing stuff that should be fogged */ void Fog_DisableGFog (void) { if (Fog_GetDensity () > 0) qfglDisable (GL_FOG); } /* Fog_StartAdditive called before drawing stuff that is additive blended -- sets fog color to black */ void Fog_StartAdditive (void) { vec3_t color = {0, 0, 0}; if (Fog_GetDensity () > 0) qfglFogfv (GL_FOG_COLOR, color); } /* Fog_StopAdditive called after drawing stuff that is additive blended -- restores fog color */ void Fog_StopAdditive (void) { if (Fog_GetDensity () > 0) qfglFogfv (GL_FOG_COLOR, Fog_GetColor ()); } //============================================================================== // // VOLUMETRIC FOG // //============================================================================== //cvar_t r_vfog = {"r_vfog", "1"}; //void Fog_DrawVFog (void) {} //void Fog_MarkModels (void) {} //============================================================================== // // INIT // //============================================================================== /* Fog_NewMap called whenever a map is loaded */ #if 0 void Fog_NewMap (void) { Fog_ParseWorldspawn (); //for global fog Fog_MarkModels (); //for volumetric fog } #endif /* Fog_Init called when quake initializes */ void Fog_Init (void) { Cmd_AddCommand ("fog", Fog_FogCommand_f, ""); //Cvar_RegisterVariable (&r_vfog, NULL); //set up global fog fog_density = 0.0; fog_red = 0.3; fog_green = 0.3; fog_blue = 0.3; qfglFogi (GL_FOG_MODE, GL_EXP2); }