1 files changed, 120 insertions, 0 deletions
diff --git a/src/display/nr-light.cpp b/src/display/nr-light.cpp
new file mode 100644
index 0000000..3009955
--- /dev/null
+++ b/src/display/nr-light.cpp
@@ -0,0 +1,120 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Light rendering helpers
+ *
+ * Author:
+ *   Jean-Rene Reinhard <jr@komite.net>
+ *
+ * Copyright (C) 2006 Jean-Rene Reinhard
+ *
+ * Released under GNU GPL v2+, read the file 'COPYING' for more information.
+ */
+
+#include <cmath>
+
+#include "display/nr-light.h"
+#include "display/nr-3dutils.h"
+#include "object/filters/distantlight.h"
+#include "object/filters/pointlight.h"
+#include "object/filters/spotlight.h"
+#include "color.h"
+
+namespace Inkscape {
+namespace Filters {
+   
+DistantLight::DistantLight(SPFeDistantLight *light, guint32 lighting_color) {
+    color = lighting_color;
+    azimuth = M_PI / 180 * light->azimuth;
+    elevation = M_PI / 180 * light->elevation;
+}
+
+DistantLight::~DistantLight() = default;
+
+void DistantLight::light_vector(NR::Fvector &v) {
+    v[X_3D] = std::cos(azimuth)*std::cos(elevation);
+    v[Y_3D] = std::sin(azimuth)*std::cos(elevation);
+    v[Z_3D] = std::sin(elevation);
+} 
+
+void DistantLight::light_components(NR::Fvector &lc) {
+    lc[LIGHT_RED] = SP_RGBA32_R_U(color);
+    lc[LIGHT_GREEN] = SP_RGBA32_G_U(color);
+    lc[LIGHT_BLUE] = SP_RGBA32_B_U(color);
+}
+
+PointLight::PointLight(SPFePointLight *light, guint32 lighting_color, const Geom::Affine &trans, int device_scale) {
+    color = lighting_color;
+    l_x = light->x * device_scale;
+    l_y = light->y * device_scale;
+    l_z = light->z * device_scale;
+    NR::convert_coord(l_x, l_y, l_z, trans);
+}
+
+PointLight::~PointLight() = default;
+
+void PointLight::light_vector(NR::Fvector &v, double x, double y, double z) {
+    v[X_3D] = l_x - x;
+    v[Y_3D] = l_y - y;
+    v[Z_3D] = l_z - z;
+    NR::normalize_vector(v);
+} 
+
+void PointLight::light_components(NR::Fvector &lc) {
+    lc[LIGHT_RED] = SP_RGBA32_R_U(color);
+    lc[LIGHT_GREEN] = SP_RGBA32_G_U(color);
+    lc[LIGHT_BLUE] = SP_RGBA32_B_U(color);
+}
+
+SpotLight::SpotLight(SPFeSpotLight *light, guint32 lighting_color, const Geom::Affine &trans, int device_scale) {
+    double p_x, p_y, p_z;
+    color = lighting_color;
+    l_x = light->x * device_scale;
+    l_y = light->y * device_scale;
+    l_z = light->z * device_scale;
+    p_x = light->pointsAtX * device_scale;
+    p_y = light->pointsAtY * device_scale;
+    p_z = light->pointsAtZ * device_scale;
+    cos_lca = std::cos(M_PI / 180 * light->limitingConeAngle);
+    speExp = light->specularExponent;
+    NR::convert_coord(l_x, l_y, l_z, trans);
+    NR::convert_coord(p_x, p_y, p_z, trans);
+    S[X_3D] = p_x - l_x;
+    S[Y_3D] = p_y - l_y;
+    S[Z_3D] = p_z - l_z;
+    NR::normalize_vector(S);
+    
+}
+
+SpotLight::~SpotLight() = default;
+
+void SpotLight::light_vector(NR::Fvector &v, double x, double y, double z) {
+    v[X_3D] = l_x - x;
+    v[Y_3D] = l_y - y;
+    v[Z_3D] = l_z - z;
+    NR::normalize_vector(v);
+} 
+
+void SpotLight::light_components(NR::Fvector &lc, const NR::Fvector &L) {
+    double spmod = (-1) * NR::scalar_product(L, S);
+    if (spmod <= cos_lca)
+        spmod = 0;
+    else
+        spmod = std::pow(spmod, speExp);
+    lc[LIGHT_RED] = spmod * SP_RGBA32_R_U(color);
+    lc[LIGHT_GREEN] = spmod * SP_RGBA32_G_U(color);
+    lc[LIGHT_BLUE] = spmod * SP_RGBA32_B_U(color);
+}
+
+} /* namespace Filters */
+} /* namespace Inkscape */
+
+/*
+  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:fileencoding=utf-8:textwidth=99 :