SRB2/src/r_sky.c
2023-03-31 14:53:31 +02:00

80 lines
2 KiB
C

// SONIC ROBO BLAST 2
//-----------------------------------------------------------------------------
// Copyright (C) 1993-1996 by id Software, Inc.
// Copyright (C) 1998-2000 by DooM Legacy Team.
// Copyright (C) 1999-2023 by Sonic Team Junior.
//
// This program is free software distributed under the
// terms of the GNU General Public License, version 2.
// See the 'LICENSE' file for more details.
//-----------------------------------------------------------------------------
/// \file r_sky.c
/// \brief Sky rendering
/// The SRB2 sky is a texture map like any
/// wall, wrapping around. A 1024 columns equal 360 degrees.
/// The default sky map is 256 columns and repeats 4 times
/// on a 320 screen.
#include "doomdef.h"
#include "doomstat.h"
#include "r_sky.h"
#include "r_local.h"
#include "w_wad.h"
#include "z_zone.h"
#include "p_maputl.h" // P_PointOnLineSide
//
// sky mapping
//
/** \brief Needed to store the number of the dummy sky flat.
Used for rendering, as well as tracking projectiles etc.
*/
INT32 skyflatnum;
/** \brief the lump number of the sky texture
*/
INT32 skytexture;
/** \brief the horizon line in a 256x128 sky texture
*/
INT32 skytexturemid;
/** \brief the scale of the sky
*/
fixed_t skyscale;
/** \brief used for keeping track of the current sky
*/
INT32 levelskynum;
INT32 globallevelskynum;
/** \brief The R_SetupSkyDraw function
Called at loadlevel after skytexture is set, or when sky texture changes.
\warning wallcolfunc should be set at R_ExecuteSetViewSize()
I don't bother because we don't use low detail anymore
\return void
*/
void R_SetupSkyDraw(void)
{
// the horizon line in a 256x128 sky texture
skytexturemid = (textures[skytexture]->height/2)<<FRACBITS;
R_SetSkyScale();
}
/** \brief The R_SetSkyScale function
set the correct scale for the sky at setviewsize
\return void
*/
void R_SetSkyScale(void)
{
fixed_t difference = vid.fdupx-(vid.dupx<<FRACBITS);
skyscale = FixedDiv(fovtan, vid.fdupx+difference);
}