newtree/source/gl_dyn_textures.c

/*
	gl_dyn_textures.c

	Dynamic texture generation.

	Copyright (C) 1996-1997  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:

		Free Software Foundation, Inc.
		59 Temple Place - Suite 330
		Boston, MA  02111-1307, USA

	$Id$
*/

#ifdef HAVE_CONFIG_H
# include <config.h>
#endif

#include "glquake.h"
#include "fractalnoise.h"

#include <stdlib.h>

static void GDT_InitDotParticleTexture (void);
static void GDT_InitSmokeParticleTexture (void);

int	part_tex_smoke[8];
int	part_tex_dot;

void GDT_Init (void)
{
	GDT_InitDotParticleTexture();
	GDT_InitSmokeParticleTexture();
}

byte	dottexture[4][4] =
{
	{0,1,1,0},
	{1,1,1,1},
	{1,1,1,1},
	{0,1,1,0},
};

static void GDT_InitDotParticleTexture (void)
{
	int		x, y;
	byte	data[4][4][4];

	//
	// particle texture
	//
	part_tex_dot = texture_extension_number++;
	glBindTexture (GL_TEXTURE_2D, part_tex_dot);

	for (x=0 ; x<4 ; x++)
	{
		for (y=0 ; y<4 ; y++)
		{
			data[y][x][0] = 244;
			data[y][x][1] = 244;
			data[y][x][2] = 244;
			data[y][x][3] = dottexture[x][y]*244;
		}
	}
	glTexImage2D (GL_TEXTURE_2D, 0, gl_alpha_format, 4, 4, 0, GL_RGBA, GL_UNSIGNED_BYTE, data);

	glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
	glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
}

static void GDT_InitSmokeParticleTexture (void)
{
	int		i, x, y, d;
	float	dx, dy;
	byte	data[32][32][4], noise1[32][32], noise2[32][32];
	for (i = 0;i < 8;i++) {
		fractalnoise(&noise1[0][0], 32);
		fractalnoise(&noise2[0][0], 32);
		for (y = 0;y < 32;y++)
			for (x = 0;x < 32;x++) {
				data[y][x][0] = data[y][x][1] = data[y][x][2] = (noise1[y][x] >> 1) + 128;
				dx = x - 16;
				dy = y - 16;
				d = noise2[y][x] * 4 - 512;
				if (d > 0) {
					if (d > 255)
						d = 255;
					d = (d * (255 - (int) (dx*dx+dy*dy))) >> 8;
					if (d < 0) d = 0;
					if (d > 255) d = 255;
					data[y][x][3] = (byte) d;
				}
				else
					data[y][x][3] = 0;
			}
		part_tex_smoke[i] = texture_extension_number++;
		glBindTexture(GL_TEXTURE_2D, part_tex_smoke[i]);
		glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
		glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
		glTexImage2D (GL_TEXTURE_2D, 0, gl_alpha_format, 32, 32, 0, GL_RGBA, GL_UNSIGNED_BYTE, data);

	}
}