static void
lic_image (GimpPixelRgn *src_rgn,
gint x,
gint y,
gdouble vx,
gdouble vy,
GimpRGB *color)
{
gdouble u, step = 2.0 * l / isteps;
gdouble xx = (gdouble) x, yy = (gdouble) y;
gdouble c, s;
GimpRGB col = { 0, 0, 0, 0 };
GimpRGB col1, col2, col3;
/* Get vector at x,y */
/* ================= */
c = vx;
s = vy;
/* Calculate integral numerically */
/* ============================== */
getpixel (src_rgn, &col1, xx + l * c, yy + l * s);
if (source_drw_has_alpha)
gimp_rgba_multiply (&col1, filter (-l));
else
gimp_rgb_multiply (&col1, filter (-l));
for (u = -l + step; u <= l; u += step)
{
getpixel (src_rgn, &col2, xx - u * c, yy - u * s);
if (source_drw_has_alpha)
{
gimp_rgba_multiply (&col2, filter (u));
col3 = col1;
gimp_rgba_add (&col3, &col2);
gimp_rgba_multiply (&col3, 0.5 * step);
gimp_rgba_add (&col, &col3);
}
else
{
gimp_rgb_multiply (&col2, filter (u));
col3 = col1;
gimp_rgb_add (&col3, &col2);
gimp_rgb_multiply (&col3, 0.5 * step);
gimp_rgb_add (&col, &col3);
}
col1 = col2;
}
if (source_drw_has_alpha)
gimp_rgba_multiply (&col, 1.0 / l);
else
gimp_rgb_multiply (&col, 1.0 / l);
gimp_rgb_clamp (&col);
*color = col;
}
static VALUE
rb_gimp_rgb_multiply (VALUE self,
VALUE factor)
{
GimpRGB result = rb2GimpRGB(self);
gimp_rgb_multiply(&result, (gdouble)NUM2DBL(factor));
return GimpRGB2rb(&result);
}
static void
compute_lic (GimpDrawable *drawable,
const guchar *scalarfield,
gboolean rotate)
{
gint xcount, ycount;
GimpRGB color;
gdouble vx, vy, tmp;
GimpPixelRgn src_rgn, dest_rgn;
gimp_pixel_rgn_init (&src_rgn, drawable,
border_x, border_y,
border_w, border_h, FALSE, FALSE);
gimp_pixel_rgn_init (&dest_rgn, drawable,
border_x, border_y,
border_w, border_h, TRUE, TRUE);
for (ycount = 0; ycount < src_rgn.h; ycount++)
{
for (xcount = 0; xcount < src_rgn.w; xcount++)
{
/* Get derivative at (x,y) and normalize it */
/* ============================================================== */
vx = gradx (scalarfield, xcount, ycount);
vy = grady (scalarfield, xcount, ycount);
/* Rotate if needed */
if (rotate)
{
tmp = vy;
vy = -vx;
vx = tmp;
}
tmp = sqrt (vx * vx + vy * vy);
if (tmp >= 0.000001)
{
tmp = 1.0 / tmp;
vx *= tmp;
vy *= tmp;
}
/* Convolve with the LIC at (x,y) */
/* ============================== */
if (licvals.effect_convolve == 0)
{
peek (&src_rgn, xcount, ycount, &color);
tmp = lic_noise (xcount, ycount, vx, vy);
if (source_drw_has_alpha)
gimp_rgba_multiply (&color, tmp);
else
gimp_rgb_multiply (&color, tmp);
}
else
{
lic_image (&src_rgn, xcount, ycount, vx, vy, &color);
}
poke (&dest_rgn, xcount, ycount, &color);
}
gimp_progress_update ((gfloat) ycount / (gfloat) src_rgn.h);
}
gimp_progress_update (1.0);
}
static GimpRGB
phong_shade (GimpVector3 *pos,
GimpVector3 *viewpoint,
GimpVector3 *normal,
GimpVector3 *light,
GimpRGB *diff_col,
GimpRGB *spec_col,
gint type)
{
GimpRGB ambientcolor, diffusecolor, specularcolor;
gdouble NL, RV, dist;
GimpVector3 L, NN, V, N;
/* Compute ambient intensity */
/* ========================= */
N = *normal;
ambientcolor = *diff_col;
gimp_rgb_multiply (&ambientcolor, mapvals.material.ambient_int);
/* Compute (N*L) term of Phong's equation */
/* ====================================== */
if (type == POINT_LIGHT)
gimp_vector3_sub (&L, light, pos);
else
L = *light;
dist = gimp_vector3_length (&L);
if (dist != 0.0)
gimp_vector3_mul (&L, 1.0 / dist);
NL = 2.0 * gimp_vector3_inner_product (&N, &L);
if (NL >= 0.0)
{
/* Compute (R*V)^alpha term of Phong's equation */
/* ============================================ */
gimp_vector3_sub (&V, viewpoint, pos);
gimp_vector3_normalize (&V);
gimp_vector3_mul (&N, NL);
gimp_vector3_sub (&NN, &N, &L);
RV = gimp_vector3_inner_product (&NN, &V);
RV = pow (RV, mapvals.material.highlight);
/* Compute diffuse and specular intensity contribution */
/* =================================================== */
diffusecolor = *diff_col;
gimp_rgb_multiply (&diffusecolor, mapvals.material.diffuse_ref);
gimp_rgb_multiply (&diffusecolor, NL);
specularcolor = *spec_col;
gimp_rgb_multiply (&specularcolor, mapvals.material.specular_ref);
gimp_rgb_multiply (&specularcolor, RV);
gimp_rgb_add (&diffusecolor, &specularcolor);
gimp_rgb_multiply (&diffusecolor, mapvals.material.diffuse_int);
gimp_rgb_clamp (&diffusecolor);
gimp_rgb_add (&ambientcolor, &diffusecolor);
}
return ambientcolor;
}
GimpRGB
get_ray_color_no_bilinear_ref (GimpVector3 *position)
{
GimpRGB color_sum;
GimpRGB color_int;
GimpRGB light_color;
GimpRGB color, env_color;
gint x;
gdouble xf, yf;
GimpVector3 normal, *p, v, r;
gint k;
gdouble tmpval;
pos_to_float (position->x, position->y, &xf, &yf);
x = RINT (xf);
if (mapvals.bump_mapped == FALSE || mapvals.bumpmap_id == -1)
normal = mapvals.planenormal;
else
normal = vertex_normals[1][(gint) RINT (xf)];
gimp_vector3_normalize (&normal);
if (mapvals.transparent_background && heights[1][x] == 0)
{
gimp_rgb_set_alpha (&color_sum, 0.0);
}
else
{
color = peek (RINT (xf), RINT (yf));
color_sum = color;
gimp_rgb_multiply (&color_sum, mapvals.material.ambient_int);
for (k = 0; k < NUM_LIGHTS; k++)
{
p = &mapvals.lightsource[k].direction;
if (!mapvals.lightsource[k].active
|| mapvals.lightsource[k].type == NO_LIGHT)
continue;
else if (mapvals.lightsource[k].type == POINT_LIGHT)
p = &mapvals.lightsource[k].position;
color_int = mapvals.lightsource[k].color;
gimp_rgb_multiply (&color_int, mapvals.lightsource[k].intensity);
light_color = phong_shade (position,
&mapvals.viewpoint,
&normal,
p,
&color,
&color_int,
mapvals.lightsource[0].type);
}
gimp_vector3_sub (&v, &mapvals.viewpoint, position);
gimp_vector3_normalize (&v);
r = compute_reflected_ray (&normal, &v);
/* Get color in the direction of r */
/* =============================== */
sphere_to_image (&r, &xf, &yf);
env_color = peek_env_map (RINT (env_width * xf),
RINT (env_height * yf));
tmpval = mapvals.material.diffuse_int;
mapvals.material.diffuse_int = 0.;
light_color = phong_shade (position,
&mapvals.viewpoint,
&normal,
&r,
&color,
&env_color,
DIRECTIONAL_LIGHT);
mapvals.material.diffuse_int = tmpval;
gimp_rgb_add (&color_sum, &light_color);
}
gimp_rgb_clamp (&color_sum);
return color_sum;
}
GimpRGB
get_ray_color_no_bilinear (GimpVector3 *position)
{
GimpRGB color;
GimpRGB color_int;
GimpRGB color_sum;
GimpRGB light_color;
gint x;
gdouble xf, yf;
GimpVector3 normal, *p;
gint k;
pos_to_float (position->x, position->y, &xf, &yf);
x = RINT (xf);
if (mapvals.transparent_background && heights[1][x] == 0)
{
gimp_rgb_set_alpha (&color_sum, 0.0);
}
else
{
color = peek (x, RINT (yf));
color_sum = color;
gimp_rgb_multiply (&color_sum, mapvals.material.ambient_int);
for (k = 0; k < NUM_LIGHTS; k++)
{
p = &mapvals.lightsource[k].direction;
if (!mapvals.lightsource[k].active
|| mapvals.lightsource[k].type == NO_LIGHT)
continue;
else if (mapvals.lightsource[k].type == POINT_LIGHT)
p = &mapvals.lightsource[k].position;
color_int = mapvals.lightsource[k].color;
gimp_rgb_multiply (&color_int, mapvals.lightsource[k].intensity);
if (mapvals.bump_mapped == FALSE || mapvals.bumpmap_id == -1)
{
light_color = phong_shade (position,
&mapvals.viewpoint,
&mapvals.planenormal,
p,
&color,
&color_int,
mapvals.lightsource[k].type);
}
else
{
normal = vertex_normals[1][x];
light_color = phong_shade (position,
&mapvals.viewpoint,
&normal,
p,
&color,
&color_int,
mapvals.lightsource[k].type);
}
gimp_rgb_add (&color_sum, &light_color);
}
}
gimp_rgb_clamp (&color_sum);
return color_sum;
}
static GimpRGB
phong_shade (GimpVector3 *position,
GimpVector3 *viewpoint,
GimpVector3 *normal,
GimpVector3 *lightposition,
GimpRGB *diff_col,
GimpRGB *light_col,
LightType light_type)
{
GimpRGB diffuse_color, specular_color;
gdouble nl, rv, dist;
GimpVector3 l, v, n, lnormal, h;
/* Compute ambient intensity */
/* ========================= */
n = *normal;
/* Compute (N*L) term of Phong's equation */
/* ====================================== */
if (light_type == POINT_LIGHT)
gimp_vector3_sub (&l, lightposition, position);
else
{
l = *lightposition;
gimp_vector3_normalize (&l);
}
dist = gimp_vector3_length (&l);
if (dist != 0.0)
gimp_vector3_mul (&l, 1.0 / dist);
nl = MAX (0., 2.0 * gimp_vector3_inner_product (&n, &l));
lnormal = l;
gimp_vector3_normalize (&lnormal);
if (nl >= 0.0)
{
/* Compute (R*V)^alpha term of Phong's equation */
/* ============================================ */
gimp_vector3_sub (&v, viewpoint, position);
gimp_vector3_normalize (&v);
gimp_vector3_add (&h, &lnormal, &v);
gimp_vector3_normalize (&h);
rv = MAX (0.01, gimp_vector3_inner_product (&n, &h));
rv = pow (rv, mapvals.material.highlight);
rv *= nl;
/* Compute diffuse and specular intensity contribution */
/* =================================================== */
diffuse_color = *light_col;
gimp_rgb_multiply (&diffuse_color, mapvals.material.diffuse_int);
diffuse_color.r *= diff_col->r;
diffuse_color.g *= diff_col->g;
diffuse_color.b *= diff_col->b;
gimp_rgb_multiply (&diffuse_color, nl);
specular_color = *light_col;
if (mapvals.material.metallic) /* for metals, specular color = diffuse color */
{
specular_color.r *= diff_col->r;
specular_color.g *= diff_col->g;
specular_color.b *= diff_col->b;
}
gimp_rgb_multiply (&specular_color, mapvals.material.specular_ref);
gimp_rgb_multiply (&specular_color, rv);
gimp_rgb_add (&diffuse_color, &specular_color);
gimp_rgb_clamp (&diffuse_color);
}
gimp_rgb_clamp (&diffuse_color);
return diffuse_color;
}