gl_image.c

Quake 2 Source code for students by Theerthan You can also download from idsoftwares.com

/*
Copyright (C) 1997-2001 Id Software, Inc.

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.

*/

#include "gl_local.h"

image_t		gltextures[MAX_GLTEXTURES];
int			numgltextures;
int			base_textureid;		// gltextures[i] = base_textureid+i

static byte			 intensitytable[256];
static unsigned char gammatable[256];

cvar_t		*intensity;

unsigned	d_8to24table[256];

qboolean GL_Upload8 (byte *data, int width, int height,  qboolean mipmap, qboolean is_sky );
qboolean GL_Upload32 (unsigned *data, int width, int height,  qboolean mipmap);


int		gl_solid_format = 3;
int		gl_alpha_format = 4;

int		gl_tex_solid_format = 3;
int		gl_tex_alpha_format = 4;

int		gl_filter_min = GL_LINEAR_MIPMAP_NEAREST;
int		gl_filter_max = GL_LINEAR;

void GL_SetTexturePalette( unsigned palette[256] )
{
	int i;
	unsigned char temptable[768];

	if ( qglColorTableEXT && gl_ext_palettedtexture->value )
	{
		for ( i = 0; i < 256; i++ )
		{
			temptable[i*3+0] = ( palette[i] >> 0 ) & 0xff;
			temptable[i*3+1] = ( palette[i] >> 8 ) & 0xff;
			temptable[i*3+2] = ( palette[i] >> 16 ) & 0xff;
		}

		qglColorTableEXT( GL_SHARED_TEXTURE_PALETTE_EXT,
						   GL_RGB,
						   256,
						   GL_RGB,
						   GL_UNSIGNED_BYTE,
						   temptable );
	}
}

void GL_EnableMultitexture( qboolean enable )
{
	if ( !qglSelectTextureSGIS && !qglActiveTextureARB )
		return;

	if ( enable )
	{
		GL_SelectTexture( GL_TEXTURE1 );
		qglEnable( GL_TEXTURE_2D );
		GL_TexEnv( GL_REPLACE );
	}
	else
	{
		GL_SelectTexture( GL_TEXTURE1 );
		qglDisable( GL_TEXTURE_2D );
		GL_TexEnv( GL_REPLACE );
	}
	GL_SelectTexture( GL_TEXTURE0 );
	GL_TexEnv( GL_REPLACE );
}

void GL_SelectTexture( GLenum texture )
{
	int tmu;

	if ( !qglSelectTextureSGIS && !qglActiveTextureARB )
		return;

	if ( texture == GL_TEXTURE0 )
	{
		tmu = 0;
	}
	else
	{
		tmu = 1;
	}

	if ( tmu == gl_state.currenttmu )
	{
		return;
	}

	gl_state.currenttmu = tmu;

	if ( qglSelectTextureSGIS )
	{
		qglSelectTextureSGIS( texture );
	}
	else if ( qglActiveTextureARB )
	{
		qglActiveTextureARB( texture );
		qglClientActiveTextureARB( texture );
	}
}

void GL_TexEnv( GLenum mode )
{
	static int lastmodes[2] = { -1, -1 };

	if ( mode != lastmodes[gl_state.currenttmu] )
	{
		qglTexEnvf( GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, mode );
		lastmodes[gl_state.currenttmu] = mode;
	}
}

void GL_Bind (int texnum)
{
	extern	image_t	*draw_chars;

	if (gl_nobind->value && draw_chars)		// performance evaluation option
		texnum = draw_chars->texnum;
	if ( gl_state.currenttextures[gl_state.currenttmu] == texnum)
		return;
	gl_state.currenttextures[gl_state.currenttmu] = texnum;
	qglBindTexture (GL_TEXTURE_2D, texnum);
}

void GL_MBind( GLenum target, int texnum )
{
	GL_SelectTexture( target );
	if ( target == GL_TEXTURE0 )
	{
		if ( gl_state.currenttextures[0] == texnum )
			return;
	}
	else
	{
		if ( gl_state.currenttextures[1] == texnum )
			return;
	}
	GL_Bind( texnum );
}

typedef struct
{
	char *name;
	int	minimize, maximize;
} glmode_t;

glmode_t modes[] = {
	{"GL_NEAREST", GL_NEAREST, GL_NEAREST},
	{"GL_LINEAR", GL_LINEAR, GL_LINEAR},
	{"GL_NEAREST_MIPMAP_NEAREST", GL_NEAREST_MIPMAP_NEAREST, GL_NEAREST},
	{"GL_LINEAR_MIPMAP_NEAREST", GL_LINEAR_MIPMAP_NEAREST, GL_LINEAR},
	{"GL_NEAREST_MIPMAP_LINEAR", GL_NEAREST_MIPMAP_LINEAR, GL_NEAREST},
	{"GL_LINEAR_MIPMAP_LINEAR", GL_LINEAR_MIPMAP_LINEAR, GL_LINEAR}
};

#define NUM_GL_MODES (sizeof(modes) / sizeof (glmode_t))

typedef struct
{
	char *name;
	int mode;
} gltmode_t;

gltmode_t gl_alpha_modes[] = {
	{"default", 4},
	{"GL_RGBA", GL_RGBA},
	{"GL_RGBA8", GL_RGBA8},
	{"GL_RGB5_A1", GL_RGB5_A1},
	{"GL_RGBA4", GL_RGBA4},
	{"GL_RGBA2", GL_RGBA2},
};

#define NUM_GL_ALPHA_MODES (sizeof(gl_alpha_modes) / sizeof (gltmode_t))

gltmode_t gl_solid_modes[] = {
	{"default", 3},
	{"GL_RGB", GL_RGB},
	{"GL_RGB8", GL_RGB8},
	{"GL_RGB5", GL_RGB5},
	{"GL_RGB4", GL_RGB4},
	{"GL_R3_G3_B2", GL_R3_G3_B2},
#ifdef GL_RGB2_EXT
	{"GL_RGB2", GL_RGB2_EXT},
#endif
};

#define NUM_GL_SOLID_MODES (sizeof(gl_solid_modes) / sizeof (gltmode_t))

/*
===============
GL_TextureMode
===============
*/
void GL_TextureMode( char *string )
{
	int		i;
	image_t	*glt;

	for (i=0 ; i< NUM_GL_MODES ; i++)
	{
		if ( !Q_stricmp( modes[i].name, string ) )
			break;
	}

	if (i == NUM_GL_MODES)
	{
		ri.Con_Printf (PRINT_ALL, "bad filter name\n");
		return;
	}

	gl_filter_min = modes[i].minimize;
	gl_filter_max = modes[i].maximize;

	// change all the existing mipmap texture objects
	for (i=0, glt=gltextures ; i<numgltextures ; i++, glt++)
	{
		if (glt->type != it_pic && glt->type != it_sky )
		{
			GL_Bind (glt->texnum);
			qglTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, gl_filter_min);
			qglTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, gl_filter_max);
		}
	}
}

/*
===============
GL_TextureAlphaMode
===============
*/
void GL_TextureAlphaMode( char *string )
{
	int		i;

	for (i=0 ; i< NUM_GL_ALPHA_MODES ; i++)
	{
		if ( !Q_stricmp( gl_alpha_modes[i].name, string ) )
			break;
	}

	if (i == NUM_GL_ALPHA_MODES)
	{
		ri.Con_Printf (PRINT_ALL, "bad alpha texture mode name\n");
		return;
	}

	gl_tex_alpha_format = gl_alpha_modes[i].mode;
}

/*
===============
GL_TextureSolidMode
===============
*/
void GL_TextureSolidMode( char *string )
{
	int		i;

	for (i=0 ; i< NUM_GL_SOLID_MODES ; i++)
	{
		if ( !Q_stricmp( gl_solid_modes[i].name, string ) )
			break;
	}

	if (i == NUM_GL_SOLID_MODES)
	{
		ri.Con_Printf (PRINT_ALL, "bad solid texture mode name\n");
		return;
	}

	gl_tex_solid_format = gl_solid_modes[i].mode;
}

/*
===============
GL_ImageList_f
===============
*/
void	GL_ImageList_f (void)
{
	int		i;
	image_t	*image;
	int		texels;
	const char *palstrings[2] =
	{
		"RGB",
		"PAL"
	};

	ri.Con_Printf (PRINT_ALL, "------------------\n");
	texels = 0;

	for (i=0, image=gltextures ; i<numgltextures ; i++, image++)
	{
		if (image->texnum <= 0)
			continue;
		texels += image->upload_width*image->upload_height;
		switch (image->type)
		{
		case it_skin:
			ri.Con_Printf (PRINT_ALL, "M");
			break;
		case it_sprite:
			ri.Con_Printf (PRINT_ALL, "S");
			break;
		case it_wall:
			ri.Con_Printf (PRINT_ALL, "W");
			break;
		case it_pic:
			ri.Con_Printf (PRINT_ALL, "P");
			break;
		default:
			ri.Con_Printf (PRINT_ALL, " ");
			break;
		}

		ri.Con_Printf (PRINT_ALL,  " %3i %3i %s: %s\n",
			image->upload_width, image->upload_height, palstrings[image->paletted], image->name);
	}
	ri.Con_Printf (PRINT_ALL, "Total texel count (not counting mipmaps): %i\n", texels);
}


/*
=============================================================================

  scrap allocation

  Allocate all the little status bar obejcts into a single texture
  to crutch up inefficient hardware / drivers

=============================================================================
*/

#define	MAX_SCRAPS		1
#define	BLOCK_WIDTH		256
#define	BLOCK_HEIGHT	256

int			scrap_allocated[MAX_SCRAPS][BLOCK_WIDTH];
byte		scrap_texels[MAX_SCRAPS][BLOCK_WIDTH*BLOCK_HEIGHT];
qboolean	scrap_dirty;

// returns a texture number and the position inside it
int Scrap_AllocBlock (int w, int h, int *x, int *y)
{
	int		i, j;
	int		best, best2;
	int		texnum;

	for (texnum=0 ; texnum<MAX_SCRAPS ; texnum++)
	{
		best = BLOCK_HEIGHT;

		for (i=0 ; i<BLOCK_WIDTH-w ; i++)
		{
			best2 = 0;

			for (j=0 ; j<w ; j++)
			{
				if (scrap_allocated[texnum][i+j] >= best)
					break;
				if (scrap_allocated[texnum][i+j] > best2)
					best2 = scrap_allocated[texnum][i+j];
			}
			if (j == w)
			{	// this is a valid spot
				*x = i;
				*y = best = best2;
			}
		}

		if (best + h > BLOCK_HEIGHT)
			continue;

		for (i=0 ; i<w ; i++)
			scrap_allocated[texnum][*x + i] = best + h;

		return texnum;
	}

	return -1;
//	Sys_Error ("Scrap_AllocBlock: full");
}

int	scrap_uploads;

void Scrap_Upload (void)
{
	scrap_uploads++;
	GL_Bind(TEXNUM_SCRAPS);
	GL_Upload8 (scrap_texels[0], BLOCK_WIDTH, BLOCK_HEIGHT, false, false );
	scrap_dirty = false;
}

/*
=================================================================

PCX LOADING

=================================================================
*/


/*
==============
LoadPCX
==============
*/
void LoadPCX (char *filename, byte **pic, byte **palette, int *width, int *height)
{
	byte	*raw;
	pcx_t	*pcx;
	int		x, y;
	int		len;
	int		dataByte, runLength;
	byte	*out, *pix;

	*pic = NULL;
	*palette = NULL;

	//
	// load the file
	//
	len = ri.FS_LoadFile (filename, (void **)&raw);
	if (!raw)
	{
		ri.Con_Printf (PRINT_DEVELOPER, "Bad pcx file %s\n", filename);
		return;
	}

	//
	// parse the PCX file
	//
	pcx = (pcx_t *)raw;

    pcx->xmin = LittleShort(pcx->xmin);
    pcx->ymin = LittleShort(pcx->ymin);
    pcx->xmax = LittleShort(pcx->xmax);
    pcx->ymax = LittleShort(pcx->ymax);
    pcx->hres = LittleShort(pcx->hres);
    pcx->vres = LittleShort(pcx->vres);
    pcx->bytes_per_line = LittleShort(pcx->bytes_per_line);
    pcx->palette_type = LittleShort(pcx->palette_type);

	raw = &pcx->data;

	if (pcx->manufacturer != 0x0a
		|| pcx->version != 5
		|| pcx->encoding != 1
		|| pcx->bits_per_pixel != 8
		|| pcx->xmax >= 640
		|| pcx->ymax >= 480)
	{
		ri.Con_Printf (PRINT_ALL, "Bad pcx file %s\n", filename);
		return;
	}

	out = malloc ( (pcx->ymax+1) * (pcx->xmax+1) );

	*pic = out;

	pix = out;

	if (palette)
	{
		*palette = malloc(768);
		memcpy (*palette, (byte *)pcx + len - 768, 768);
	}

	if (width)
		*width = pcx->xmax+1;
	if (height)
		*height = pcx->ymax+1;

	for (y=0 ; y<=pcx->ymax ; y++, pix += pcx->xmax+1)
	{
		for (x=0 ; x<=pcx->xmax ; )
		{
			dataByte = *raw++;

			if((dataByte & 0xC0) == 0xC0)
			{
				runLength = dataByte & 0x3F;
				dataByte = *raw++;
			}
			else
				runLength = 1;

			while(runLength-- > 0)
				pix[x++] = dataByte;
		}

	}

	if ( raw - (byte *)pcx > len)
	{
		ri.Con_Printf (PRINT_DEVELOPER, "PCX file %s was malformed", filename);
		free (*pic);
		*pic = NULL;
	}

	ri.FS_FreeFile (pcx);
}

/*