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/**
** sipp - SImple Polygon Processor
**
** A general 3d graphic package
**
** Copyright Equivalent Software HB 1992
**
** 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 1, or 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 can receive a copy of the GNU General Public License from the
** Free Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
**/
/**
** shaders.h - This include file defines the different shaders availiable
** in sipp. Each shader is defined by a structure containing
** the necessary parameters to describe how a surface should
** be shaded with that particular shader, and the extern
** declaration of the shader function itself.
**/
#ifndef _SHADERS_H
#define _SHADERS_H
#include <sipp.h>
/*
* Surface description used in phong_shader().
*/
typedef struct {
double ambient; /* Fraction of color visible in ambient light */
double diffuse; /* Diffuse reflexion factor */
double specular; /* Specular reflexion factor */
int spec_exp; /* Exponent in the specular calculation */
Color color; /* Color of the surface */
Color opacity; /* Opacity of the surface */
} Phong_desc;
/*
* Surface description used in strauss_shader().
*/
typedef struct {
double ambient; /* Fraction of color visible in ambient light */
double smoothness; /* Smoothness of the surface [0, 1] */
double metalness; /* Metalness of the surface [0, 1] */
Color color; /* Base color of the surface */
Color opacity; /* Opacity of the surface */
} Strauss_desc;
/*
* Surface description for the bozo shader.
*/
typedef struct {
Color *colors;
int no_of_cols;
double ambient;
double specular;
double c3;
double scale; /* Scale the texture by this value */
Color opacity; /* Opacity of the surface */
} Bozo_desc;
/*
* Surface description used by the wood shader. This shader
* creates a solid texture (using noise & turbulence) that
* simulates wood.
*/
typedef struct {
double ambient;
double specular;
double c3;
double scale; /* Scale the wood texture by this value */
Color base; /* "Base" color of the surface */
Color ring; /* Color of the darker rings */
Color opacity; /* Opacity of the surface */
} Wood_desc;
/*
* Surface description used by the marble shader. marble_shader
* creates a solid texture (using noise & turbulence) that
* simulates marble.
*/
typedef struct {
double ambient;
double specular;
double c3;
double scale; /* Scale the marble texture by this value */
Color base; /* "Base" color of the surface */
Color strip; /* Color of the "stripes" in the marble */
Color opacity; /* Opacity of the surface */
} Marble_desc;
/*
* Surface description used by the granite shader. granite_shader
* creates a solid texture (using noise) that mixes two colors
* to simulate granite.
*/
typedef struct {
double ambient;
double specular;
double c3;
double scale; /* Scale the texture by this value */
Color col1; /* The two color components */
Color col2;
Color opacity; /* Opacity of the surface */
} Granite_desc;
/*
* Mask shader. It uses mask image (ususally a bitmap) to
* choose between two other shaders. When a
* surface is shaded it calls masker() to check the
* u, v coordinate in the mask and calls one of two other
* shaders depending of the outcome of that test.
*/
typedef struct {
Shader *t_shader; /* Shader to call if mask(x, y) != 0 */
void *t_surface; /* Surface description for fg_shader */
Shader *f_shader; /* Shader to call if mask(x, y) == 0 */
void *f_surface; /* Surface description for bg_shader */
void *mask_data; /* Pointer to data for masking function */
bool (*masker)(); /* Function that tests a pixel value */
} Mask_desc;
/*
* Surface description for the bumpy_shader(). This shader
* fiddles with the surface normals of a surface so the surface
* looks bumpy.
*/
typedef struct {
Shader *shader;
void *surface;
double scale;
bool bumpflag;
bool holeflag;
} Bumpy_desc;
/*
* Declarations of the actual shading functions.
*/
extern void
phong_shader _ANSI_ARGS_((Vector *pos,
Vector *normal,
Vector *texture,
Vector *view_vec,
Lightsource *lights,
Phong_desc *pd,
Color *color,
Color *opacity));
extern void
strauss_shader _ANSI_ARGS_((Vector *pos,
Vector *normal,
Vector *texture,
Vector *view_vec,
Lightsource *lights,
Strauss_desc *sd,
Color *color,
Color *opacity));
extern void
marble_shader _ANSI_ARGS_((Vector *pos,
Vector *normal,
Vector *texture,
Vector *view_vec,
Lightsource *lights,
Marble_desc *md,
Color *color,
Color *opacity));
extern void
granite_shader _ANSI_ARGS_((Vector *pos,
Vector *normal,
Vector *texture,
Vector *view_vec,
Lightsource *lights,
Granite_desc *gd,
Color *color,
Color *opacity));
extern void
bozo_shader _ANSI_ARGS_((Vector *pos,
Vector *normal,
Vector *texture,
Vector *view_vec,
Lightsource *lights,
Bozo_desc *bd,
Color *color,
Color *opacity));
extern void
mask_shader _ANSI_ARGS_((Vector *pos,
Vector *normal,
Vector *texture,
Vector *view_vec,
Lightsource *lights,
Mask_desc *md,
Color *color,
Color *opacity));
extern void
bumpy_shader _ANSI_ARGS_((Vector *pos,
Vector *normal,
Vector *texture,
Vector *view_vec,
Lightsource *lights,
Bumpy_desc *bd,
Color *color,
Color *opacity));
extern void
planet_shader _ANSI_ARGS_((Vector *pos,
Vector *normal,
Vector *texture,
Vector *view_vec,
Lightsource *lights,
Surf_desc *sd,
Color *color,
Color *opacity));
extern void
wood_shader _ANSI_ARGS_((Vector *pos,
Vector *normal,
Vector *texture,
Vector *view_vec,
Lightsource *lights,
Wood_desc *wd,
Color *color,
Color *opacity));
#endif /* _SHADERS_H */
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