nr-filter-specularlighting.cpp revision 0f1b8f53ed81c3a02f55223cd3eb359f123bc565
/*
* feSpecularLighting renderer
*
* Authors:
* Niko Kiirala <niko@kiirala.com>
* Jean-Rene Reinhard <jr@komite.net>
*
* Copyright (C) 2007 authors
*
* Released under GNU GPL, read the file 'COPYING' for more information
*/
#include <glib/gmessages.h>
#include <cmath>
#include "display/nr-3dutils.h"
#include "display/nr-arena-item.h"
#include "display/nr-filter-specularlighting.h"
#include "display/nr-filter-getalpha.h"
#include "display/nr-filter-slot.h"
#include "display/nr-filter-utils.h"
#include "display/nr-light.h"
#include "libnr/nr-blit.h"
#include "libnr/nr-pixblock.h"
#include "libnr/nr-matrix.h"
#include "libnr/nr-rect-l.h"
#include "color.h"
namespace NR {
FilterSpecularLighting::FilterSpecularLighting()
{
light_type = NO_LIGHT;
specularConstant = 1;
specularExponent = 1;
surfaceScale = 1;
lighting_color = 0xffffffff;
}
FilterPrimitive * FilterSpecularLighting::create() {
return new FilterSpecularLighting();
}
FilterSpecularLighting::~FilterSpecularLighting()
{}
//Investigating Phong Lighting model we should not take N.H but
//R.E which equals to 2*N.H^2 - 1
//replace the second line by
//gdouble scal = scalar_product((N), (H)); scal = 2 * scal * scal - 1;\
//to get the expected formula
#define COMPUTE_INTER(inter, H, N, ks, speculaExponent) \
do {\
gdouble scal = scalar_product((N), (H)); \
if (scal <= 0)\
(inter) = 0;\
else\
(inter) = (ks) * std::pow(scal, (specularExponent));\
}while(0)
int FilterSpecularLighting::render(FilterSlot &slot, Matrix const &trans) {
NRPixBlock *in = filter_get_alpha(slot.get(_input));
NRPixBlock *out = new NRPixBlock;
//Fvector *L = NULL; //vector to the light
int w = in->area.x1 - in->area.x0;
int h = in->area.y1 - in->area.y0;
int x0 = in->area.x0;
int y0 = in->area.y0;
int i, j;
//As long as FilterRes and kernel unit is not supported we hardcode the
//default value
int dx = 1; //TODO setup
int dy = 1; //TODO setup
//surface scale
//TODO for the time being, assumes userSpaceOnUse
gdouble ss = surfaceScale * trans[0];
gdouble ks = specularConstant; //diffuse lighting constant
Fvector L, N, LC, H;
gdouble inter;
nr_pixblock_setup_fast(out, in->mode,
in->area.x0, in->area.y0, in->area.x1, in->area.y1,
true);
unsigned char *data_i = NR_PIXBLOCK_PX (in);
unsigned char *data_o = NR_PIXBLOCK_PX (out);
//No light, nothing to do
switch (light_type) {
case DISTANT_LIGHT:
//the light vector is constant
{
DistantLight *dl = new DistantLight(light.distant, lighting_color);
dl->light_vector(L);
dl->light_components(LC);
normalized_sum(H, L, EYE_VECTOR);
//finish the work
for (i = 0, j = 0; i < w*h; i++) {
compute_surface_normal(N, ss, in, i / w, i % w, dx, dy);
COMPUTE_INTER(inter, N, H, ks, specularExponent);
data_o[j++] = CLAMP_D_TO_U8(inter * LC[LIGHT_RED]);
data_o[j++] = CLAMP_D_TO_U8(inter * LC[LIGHT_GREEN]);
data_o[j++] = CLAMP_D_TO_U8(inter * LC[LIGHT_BLUE]);
data_o[j++] = MAX(MAX(data_o[j-3], data_o[j-2]), data_o[j-1]);
}
out->empty = FALSE;
delete dl;
}
break;
case POINT_LIGHT:
{
PointLight *pl = new PointLight(light.point, lighting_color, trans);
pl->light_components(LC);
//TODO we need a reference to the filter to determine primitiveUnits
//slot._arena_item->filter seems to be ok on simple examples
//for now assume userSpaceOnUse
//if objectBoundingBox is used, use a different matrix for light_vector
//finish the work
for (i = 0, j = 0; i < w*h; i++) {
compute_surface_normal(N, ss, in, i / w, i % w, dx, dy);
pl->light_vector(L,
i % w + x0,
i / w + y0,
ss * (double) data_i[4*i+3]/ 255);
normalized_sum(H, L, EYE_VECTOR);
COMPUTE_INTER(inter, N, H, ks, specularExponent);
data_o[j++] = CLAMP_D_TO_U8(inter * LC[LIGHT_RED]);
data_o[j++] = CLAMP_D_TO_U8(inter * LC[LIGHT_GREEN]);
data_o[j++] = CLAMP_D_TO_U8(inter * LC[LIGHT_BLUE]);
data_o[j++] = MAX(MAX(data_o[j-3], data_o[j-2]), data_o[j-1]);
}
out->empty = FALSE;
delete pl;
}
break;
case SPOT_LIGHT:
{
SpotLight *sl = new SpotLight(light.spot, lighting_color, trans);
//TODO we need a reference to the filter to determine primitiveUnits
//slot._arena_item->filter seems to be ok on simple examples
//for now assume userSpaceOnUse
//if objectBoundingBox is used, use a different matrix for light_vector
//finish the work
for (i = 0, j = 0; i < w*h; i++) {
compute_surface_normal(N, ss, in, i / w, i % w, dx, dy);
sl->light_vector(L,
i % w + x0,
i / w + y0,
ss * (double) data_i[4*i+3]/ 255);
sl->light_components(LC, L);
normalized_sum(H, L, EYE_VECTOR);
COMPUTE_INTER(inter, N, H, ks, specularExponent);
data_o[j++] = CLAMP_D_TO_U8(inter * LC[LIGHT_RED]);
data_o[j++] = CLAMP_D_TO_U8(inter * LC[LIGHT_GREEN]);
data_o[j++] = CLAMP_D_TO_U8(inter * LC[LIGHT_BLUE]);
data_o[j++] = MAX(MAX(data_o[j-3], data_o[j-2]), data_o[j-1]);
}
out->empty = FALSE;
delete sl;
}
break;
//else unknown light source, doing nothing
case NO_LIGHT:
default:
{
if (light_type != NO_LIGHT)
g_warning("unknown light source %d", light_type);
out->empty = false;
}
}
//finishing
slot.set(_output, out);
delete in;
return 0;
}
} /* namespace NR */
/*
Local Variables:
mode:c++
c-file-style:"stroustrup"
c-file-offsets:((innamespace . 0)(inline-open . 0)(case-label . +))
indent-tabs-mode:nil
fill-column:99
End:
*/
// vim: filetype=cpp:expandtab:shiftwidth=4:tabstop=8:softtabstop=4:encoding=utf-8:textwidth=99 :