/*
* usage: bn_noise_fbm X Y Z h_val lacunarity octaves
*
*/
int
bn_cmd_noise(ClientData clientData,
Tcl_Interp *interp,
int argc,
char **argv)
{
point_t pt;
double h_val;
double lacunarity;
double octaves;
double val;
if (argc != 7) {
Tcl_AppendResult(interp, "wrong # args: should be \"",
argv[0], " X Y Z h_val lacunarity octaves\"",
NULL);
return TCL_ERROR;
}
pt[0] = atof(argv[1]);
pt[1] = atof(argv[2]);
pt[2] = atof(argv[3]);
h_val = atof(argv[4]);
lacunarity = atof(argv[5]);
octaves = atof(argv[6]);
if (!strcmp("bn_noise_turb", argv[0])) {
val = bn_noise_turb(pt, h_val, lacunarity, octaves);
Tcl_SetObjResult( interp, Tcl_NewDoubleObj(val) );
} else if (!strcmp("bn_noise_fbm", argv[0])) {
val = bn_noise_fbm(pt, h_val, lacunarity, octaves);
Tcl_SetObjResult( interp, Tcl_NewDoubleObj(val) );
} else {
Tcl_AppendResult(interp, "Unknown noise type \"",
argv[0], "\"", NULL);
return TCL_ERROR;
}
return TCL_OK;
}
int
scloud_render(struct application *ap, const struct partition *pp, struct shadework *swp, void *dp)
{
register struct scloud_specific *scloud_sp =
(struct scloud_specific *)dp;
point_t in_pt; /* point where ray enters scloud solid */
point_t out_pt; /* point where ray leaves scloud solid */
point_t pt;
vect_t v_cloud;/* vector representing ray/solid intersection */
double thickness; /* magnitude of v_cloud (distance through solid) */
int steps; /* # of samples along ray/solid intersection */
double step_delta;/* distance between sample points, texture space */
int i;
double val;
double trans;
point_t incident_light = VINIT_ZERO;
double delta_dpmm;
double density;
struct shadework sub_sw;
struct light_specific *lp;
RT_CHECK_PT(pp);
RT_AP_CHECK(ap);
RT_CK_REGION(pp->pt_regionp);
/* compute the ray/solid in and out points,
* and transform them into "shader space" coordinates
*/
VJOIN1(pt, ap->a_ray.r_pt, pp->pt_inhit->hit_dist, ap->a_ray.r_dir);
MAT4X3PNT(in_pt, scloud_sp->mtos, pt);
VJOIN1(pt, ap->a_ray.r_pt, pp->pt_outhit->hit_dist, ap->a_ray.r_dir);
MAT4X3PNT(out_pt, scloud_sp->mtos, pt);
/* get ray/solid intersection vector (in noise space)
* and compute thickness of solid (in noise space) along ray path
*/
VSUB2(v_cloud, out_pt, in_pt);
thickness = MAGNITUDE(v_cloud);
/* The noise field used by the bn_noise_turb and bn_noise_fbm routines
* has a maximum frequency of about 1 cycle per integer step in
* noise space. Each octave increases this frequency by the
* "lacunarity" factor. To sample this space adequately we need
*
* 4 samples per integer step for the first octave,
* lacunarity * 4 samples/step for the second octave,
* lacunarity^2 * 4 samples/step for the third octave,
* lacunarity^3 * 4 samples/step for the forth octave,
*
* so for a computation with 4 octaves we need something on the
* order of lacunarity^3 * 4 samples per integer step in noise space.
*/
steps = pow(scloud_sp->lacunarity, scloud_sp->octaves-1) * 4;
step_delta = thickness / (double)steps;
if (rdebug&RDEBUG_SHADE)
bu_log("steps=%d delta=%g thickness=%g\n",
steps, step_delta, thickness);
VUNITIZE(v_cloud);
VMOVE(pt, in_pt);
trans = 1.0;
delta_dpmm = scloud_sp->max_d_p_mm - scloud_sp->min_d_p_mm;
sub_sw = *swp; /* struct copy */
sub_sw.sw_inputs = MFI_HIT;
for (i=0; i < steps; i++) {
/* compute the next point in the cloud space */
VJOIN1(pt, in_pt, i*step_delta, v_cloud);
/* get turbulence value (0 .. 1) */
val = bn_noise_turb(pt, scloud_sp->h_val,
scloud_sp->lacunarity, scloud_sp->octaves);
density = scloud_sp->min_d_p_mm + val * delta_dpmm;
val = exp(- density * step_delta);
trans *= val;
if (swp->sw_xmitonly) continue;
/* need to set the hit in our fake shadework structure */
MAT4X3PNT(sub_sw.sw_hit.hit_point, scloud_sp->stom, pt);
sub_sw.sw_transmit = trans;
sub_sw.sw_inputs = MFI_HIT;
light_obs(ap, &sub_sw, swp->sw_inputs);
/* now we know how much light has arrived from each
* light source to this point
*/
for (i=ap->a_rt_i->rti_nlights-1; i >= 0; i--) {
lp = (struct light_specific *)swp->sw_visible[i];
if (lp == LIGHT_NULL) continue;
/* compute how much light has arrived at
* this location
*/
incident_light[0] += sub_sw.sw_intensity[3*i+0] *
lp->lt_color[0] * sub_sw.sw_lightfract[i];
incident_light[1] += sub_sw.sw_intensity[3*i+1] *
lp->lt_color[1] * sub_sw.sw_lightfract[i];
incident_light[2] += sub_sw.sw_intensity[3*i+2] *
lp->lt_color[2] * sub_sw.sw_lightfract[i];
}
VSCALE(incident_light, incident_light, trans);
}
/* scloud is basically a white object with partial transparency */
swp->sw_transmit = trans;
if (swp->sw_xmitonly) return 1;
/*
* At the point of maximum opacity, check light visibility
* for light color and cloud shadowing.
* OOPS: Don't use an interior point, or light_visibility()
* will see an attenuated light source.
*/
swp->sw_hit.hit_dist = pp->pt_inhit->hit_dist;
VJOIN1(swp->sw_hit.hit_point, ap->a_ray.r_pt, swp->sw_hit.hit_dist,
ap->a_ray.r_dir);
VREVERSE(swp->sw_hit.hit_normal, ap->a_ray.r_dir);
swp->sw_inputs |= MFI_HIT | MFI_NORMAL;
light_obs(ap, swp, swp->sw_inputs);
VSETALL(incident_light, 0);
for (i=ap->a_rt_i->rti_nlights-1; i>=0; i--) {
struct light_specific *lp2;
if ((lp2 = (struct light_specific *)swp->sw_visible[i]) == LIGHT_NULL)
continue;
/* XXX don't have a macro for this */
incident_light[0] += swp->sw_intensity[3*i+0] * lp2->lt_color[0];
incident_light[1] += swp->sw_intensity[3*i+1] * lp2->lt_color[1];
incident_light[2] += swp->sw_intensity[3*i+2] * lp2->lt_color[2];
}
VELMUL(swp->sw_color, swp->sw_color, incident_light);
if (rdebug&RDEBUG_SHADE) {
pr_shadework("scloud: after light vis, before rr_render", swp);
}
if (swp->sw_reflect > 0 || swp->sw_transmit > 0)
(void)rr_render(ap, pp, swp);
return 1;
}
/*
* F I R E _ R E N D E R
*
* This is called (from viewshade() in shade.c) once for each hit point
* to be shaded. The purpose here is to fill in values in the shadework
* structure.
*/
int
fire_render(struct application *ap, struct partition *pp, struct shadework *swp, char *dp)
/* defined in material.h */
/* ptr to the shader-specific struct */
{
#define DEBUG_SPACE_PRINT(str, i_pt, o_pt) \
if (rdebug&RDEBUG_SHADE || fire_sp->fire_debug ) { \
bu_log("fire_render() %s space \n", str); \
bu_log("fire_render() i_pt(%g %g %g)\n", V3ARGS(i_pt) ); \
bu_log("fire_render() o_pt(%g %g %g)\n", V3ARGS(o_pt) ); \
}
#define SHADER_TO_NOISE(n_pt, sh_pt, fire_sp, zdelta) { \
point_t tmp_pt; \
tmp_pt[X] = sh_pt[X]; \
tmp_pt[Y] = sh_pt[Y]; \
if ( ! NEAR_ZERO(fire_sp->fire_stretch, SQRT_SMALL_FASTF) ) \
tmp_pt[Z] = exp( (sh_pt[Z]+0.125) * -fire_sp->fire_stretch ); \
else \
tmp_pt[Z] = sh_pt[Z]; \
MAT4X3PNT(n_pt, fire_sp->fire_sh_to_noise, tmp_pt); \
n_pt[Z] += zdelta; \
}
register struct fire_specific *fire_sp =
(struct fire_specific *)dp;
point_t m_i_pt, m_o_pt; /* model space in/out points */
point_t sh_i_pt, sh_o_pt; /* shader space in/out points */
point_t noise_i_pt, noise_o_pt; /* shader space in/out points */
point_t noise_pt;
point_t color;
vect_t noise_r_dir;
double noise_r_thick;
int i;
double samples_per_unit_noise;
double noise_dist_per_sample;
point_t shader_pt;
vect_t shader_r_dir;
double shader_r_thick;
double shader_dist_per_sample;
double noise_zdelta;
int samples;
double dist;
double noise_val;
double lumens;
/* check the validity of the arguments we got */
RT_AP_CHECK(ap);
RT_CHECK_PT(pp);
CK_fire_SP(fire_sp);
if (rdebug&RDEBUG_SHADE || fire_sp->fire_debug ) {
/* bu_struct_print( "fire_render Parameters:", fire_print_tab, (char *)fire_sp ); */
bu_log("fire_render()\n");
}
/* If we are performing the shading in "region" space, we must
* transform the hit point from "model" space to "region" space.
* See the call to db_region_mat in fire_setup().
*/
/*
* Compute the ray/solid in and out points,
*/
VMOVE(m_i_pt, swp->sw_hit.hit_point);
VJOIN1(m_o_pt, ap->a_ray.r_pt, pp->pt_outhit->hit_dist, ap->a_ray.r_dir);
DEBUG_SPACE_PRINT("model", m_i_pt, m_o_pt);
/* map points into shader space */
MAT4X3PNT(sh_i_pt, fire_sp->fire_m_to_sh, m_i_pt);
MAT4X3PNT(sh_o_pt, fire_sp->fire_m_to_sh, m_o_pt);
DEBUG_SPACE_PRINT("shader", sh_i_pt, sh_o_pt);
noise_zdelta = fire_sp->fire_flicker * swp->sw_frametime;
SHADER_TO_NOISE(noise_i_pt, sh_i_pt, fire_sp, noise_zdelta);
SHADER_TO_NOISE(noise_o_pt, sh_o_pt, fire_sp, noise_zdelta);
VSUB2(noise_r_dir, noise_o_pt, noise_i_pt);
noise_r_thick = MAGNITUDE(noise_r_dir);
if (rdebug&RDEBUG_SHADE || fire_sp->fire_debug ) {
bu_log("fire_render() noise_r_dir (%g %g %g)\n",
V3ARGS(noise_r_dir) );
bu_log("fire_render() noise_r_thick %g\n", noise_r_thick);
}
/* compute number of samples per unit length in noise space.
*
* The noise field used by the bn_noise_turb and bn_noise_fbm routines
* has a maximum frequency of about 1 cycle per integer step in
* noise space. Each octave increases this frequency by the
* "lacunarity" factor. To sample this space adequately, nyquist
* tells us we need at least 4 samples/cycle at the highest octave
* rate.
*/
samples_per_unit_noise =
pow(fire_sp->noise_lacunarity, fire_sp->noise_octaves-1) * 4.0;
noise_dist_per_sample = 1.0 / samples_per_unit_noise;
samples = samples_per_unit_noise * noise_r_thick;
if (samples < 1) samples = 1;
if (rdebug&RDEBUG_SHADE || fire_sp->fire_debug ) {
bu_log("samples:%d\n", samples);
bu_log("samples_per_unit_noise %g\n", samples_per_unit_noise);
bu_log("noise_dist_per_sample %g\n", noise_dist_per_sample);
}
/* To do the exponential stretch and decay properly we need to
* do the computations in shader space, and convert the points
* to noise space. Performance pig.
*/
VSUB2(shader_r_dir, sh_o_pt, sh_i_pt);
shader_r_thick = MAGNITUDE(shader_r_dir);
VUNITIZE(shader_r_dir);
shader_dist_per_sample = shader_r_thick / samples;
lumens = 0.0;
for (i = 0; i < samples; i++) {
dist = (double)i * shader_dist_per_sample;
VJOIN1(shader_pt, sh_i_pt, dist, shader_r_dir);
SHADER_TO_NOISE(noise_pt, shader_pt, fire_sp, noise_zdelta);
noise_val = bn_noise_turb(noise_pt, fire_sp->noise_h_val,
fire_sp->noise_lacunarity, fire_sp->noise_octaves);
if (rdebug&RDEBUG_SHADE || fire_sp->fire_debug )
bu_log("bn_noise_turb(%g %g %g) = %g\n",
V3ARGS(noise_pt),
noise_val);
/* XXX
* When doing the exponential stretch, we scale the noise
* value by the height in shader space
*/
if ( NEAR_ZERO(fire_sp->fire_stretch, SQRT_SMALL_FASTF) )
lumens += noise_val * 0.025;
else {
register double t;
t = lumens;
lumens += noise_val * 0.025 * (1.0 -shader_pt[Z]);
if (rdebug&RDEBUG_SHADE || fire_sp->fire_debug )
bu_log("lumens:%g = %g + %g * %g\n",
lumens, t, noise_val,
0.025 * (1.0 - shader_pt[Z]) );
}
if (lumens >= 1.0) {
lumens = 1.0;
if (rdebug&RDEBUG_SHADE || fire_sp->fire_debug )
bu_log("early exit from lumens loop\n");
break;
}
}
if (rdebug&RDEBUG_SHADE || fire_sp->fire_debug )
bu_log("lumens = %g\n", lumens);
if (lumens < 0.0) lumens = 0.0;
else if (lumens > 1.0) lumens = 1.0;
rt_dspline_n(color, fire_sp->fire_colorspline_mat, (double *)flame_colors,
18, 3, lumens);
VMOVE(swp->sw_color, color);
/* VSETALL(swp->sw_basecolor, 1.0);*/
swp->sw_transmit = 1.0 - (lumens * 4.);
if (swp->sw_reflect > 0 || swp->sw_transmit > 0 )
(void)rr_render( ap, pp, swp );
return(1);
}
/**
* @brief
* usage: noise_slice xdim ydim inv h_val lac octaves dX dY dZ sX [sY sZ]
*
* The idea here is to get a whole slice of noise at once, thereby
* avoiding the overhead of doing this in Tcl.
*/
int
bn_cmd_noise_slice(ClientData clientData,
Tcl_Interp *interp,
int argc,
char **argv)
{
double h_val;
double lacunarity;
double octaves;
vect_t delta; /* translation to noise space */
vect_t scale; /* scale to noise space */
unsigned xdim; /* # samples X direction */
unsigned ydim; /* # samples Y direction */
unsigned xval, yval;
#define NOISE_FBM 0
#define NOISE_TURB 1
int noise_type = NOISE_FBM;
double val;
point_t pt;
if (argc != 7) {
Tcl_AppendResult(interp, "wrong # args: should be \"",
argv[0], " Xdim Ydim Zval h_val lacunarity octaves\"",
NULL);
return TCL_ERROR;
}
xdim = atoi(argv[0]);
ydim = atoi(argv[1]);
VSETALL(delta, 0.0);
VSETALL(scale, 1.);
pt[Z] = delta[Z] = atof(argv[2]);
h_val = atof(argv[3]);
lacunarity = atof(argv[4]);
octaves = atof(argv[5]);
switch (noise_type) {
case NOISE_FBM:
for (yval = 0; yval < ydim; yval++) {
pt[Y] = yval * scale[Y] + delta[Y];
for (xval = 0; xval < xdim; xval++) {
pt[X] = xval * scale[X] + delta[X];
val = bn_noise_fbm(pt, h_val, lacunarity, octaves);
}
}
break;
case NOISE_TURB:
for (yval = 0; yval < ydim; yval++) {
pt[Y] = yval * scale[Y] + delta[Y];
for (xval = 0; xval < xdim; xval++) {
pt[X] = xval * scale[X] + delta[X];
val = bn_noise_turb(pt, h_val, lacunarity, octaves);
}
}
break;
}
pt[0] = atof(argv[1]);
pt[1] = atof(argv[2]);
pt[2] = atof(argv[3]);
h_val = atof(argv[4]);
lacunarity = atof(argv[5]);
octaves = atof(argv[6]);
if (!strcmp("bn_noise_turb", argv[0])) {
val = bn_noise_turb(pt, h_val, lacunarity, octaves);
Tcl_SetObjResult( interp, Tcl_NewDoubleObj(val) );
} else if (!strcmp("bn_noise_fbm", argv[0])) {
val = bn_noise_fbm(pt, h_val, lacunarity, octaves);
Tcl_SetObjResult( interp, Tcl_NewDoubleObj(val) );
} else {
Tcl_AppendResult(interp, "Unknown noise type \"",
argv[0], "\"", NULL);
return TCL_ERROR;
}
return TCL_OK;
}
