has a new quadratic formula for attenuation and better weighing for multiple lights

This commit is contained in:
Asad M. Zaman 2004-09-15 22:19:57 +00:00
parent 19e402be97
commit 34f16c04b0

View File

@ -117,13 +117,17 @@ cull_callback(CullTraverser *, CullTraverserData &data,
// Access: Public
// Description: Gets the node's position and based on distance from
// lights in the lightgroup calculates the color to be
// modulated in
// modulated in. If the avatar is in the range of
// multiple lights, then determine, which light it is
// closer to, and get the weight of the scene_color
// in respect to that light's proximity.
////////////////////////////////////////////////////////////////////
CPT(RenderAttrib) PolylightEffect::
do_poly_light(const CullTraverserData *data, const TransformState *node_transform) const {
float fd; // Variable for quadratic attenuation
//static bool was_under_polylight = false;
float dist; // To calculate the distance of each light from the node
float r,g,b; // To hold the color calculation
float min_dist; // hold the dist from light that avatar is closer to
int num_lights = 0; // Keep track of number of lights for division
float light_scale; // Variable to calculate attenuation
float weight_scale; // Variable to compensate snap of color when you walk inside the light volume
@ -133,6 +137,14 @@ do_poly_light(const CullTraverserData *data, const TransformState *node_transfor
r = g = b = 1.0;
Rcollect = Gcollect = Bcollect = 0.0;
// get the avatar's base color scale
NodePath parent = data->_node_path.get_node_path().get_parent();
Colorf scene_color = parent.get_color_scale();
if (polylight_info) {
pgraph_cat.info() << "parent node name " << parent.get_name() << endl;
pgraph_cat.info() << "parent color scale = " << scene_color << endl;
}
min_dist = 100000.0;
// Cycle through all the lights in this effect's lightgroup
LightGroup::const_iterator light_iter;
for (light_iter = _lightgroup.begin(); light_iter != _lightgroup.end(); light_iter++){
@ -157,9 +169,9 @@ do_poly_light(const CullTraverserData *data, const TransformState *node_transfor
if (dist <= light_radius) { // If node is in range of this light
if (polylight_info) {
pgraph_cat.info() << "light's position = " << light->get_pos() << endl;
pgraph_cat.info() << "relative position = " << point << endl;
pgraph_cat.info() << "effect center = " << _effect_center << endl;
pgraph_cat.debug() << "light's position = " << light->get_pos() << endl;
pgraph_cat.debug() << "relative position = " << point << endl;
pgraph_cat.debug() << "effect center = " << _effect_center << endl;
//pgraph_cat.info() << "close to this light = " << light->get_name() << endl;
pgraph_cat.info() << "dist = " << dist << ";radius = " << light_radius << endl;
}
@ -173,9 +185,12 @@ do_poly_light(const CullTraverserData *data, const TransformState *node_transfor
//light_color = light->get_color_scenegraph();
}
float ratio = dist/light_radius;
if (light_attenuation == PolylightNode::ALINEAR) {
light_scale = (light_radius - dist)/light_radius;
light_scale = 1.0 - ratio;
} else if (light_attenuation == PolylightNode::AQUADRATIC) {
/*
float fd; // Variable for quadratic attenuation
float light_a0 = light->get_a0();
float light_a1 = light->get_a1();
float light_a2 = light->get_a2();
@ -188,24 +203,45 @@ do_poly_light(const CullTraverserData *data, const TransformState *node_transfor
} else {
light_scale = 1.0;
}
*/
//light_scale = 1.0 - ratio*ratio; // graph of 1-x^2
ratio = 1 - ratio;
if (ratio <= 0.8)
light_scale = (ratio*ratio)*(3-2*ratio); //graph of x^2(3-x)
else
light_scale = 1.0;
} else {
light_scale = 1.0;
}
// Keep accumulating each lights contribution...
// we have to prevent color snap, so factor in the weight.
// weight becomes negligent as you are closer to the light
// and opposite otherwise
weight_scale = _weight * (1.0 - light_scale);
if (min_dist > dist) {
min_dist = dist;
// Keep accumulating each lights contribution...
// we have to prevent color snap, so factor in the weight.
// weight becomes negligent as you are closer to the light
// and opposite otherwise
weight_scale = _weight * (1.0 - light_scale);
}
if (polylight_info) {
pgraph_cat.debug() << "weight_scale = " << weight_scale
pgraph_cat.info() << "weight_scale = " << weight_scale
<< "; light_scale " << light_scale << endl;
}
Rcollect += light_color[0] * light_scale;
Gcollect += light_color[1] * light_scale;
Bcollect += light_color[2] * light_scale;
/*
Rcollect += light_color[0] * light_scale + scene_color[0] * weight_scale;
Gcollect += light_color[1] * light_scale + scene_color[1] * weight_scale;
Bcollect += light_color[2] * light_scale + scene_color[2] * weight_scale;
*/
/*
Rcollect += light_color[0] * light_scale + weight_scale;
Gcollect += light_color[1] * light_scale + weight_scale;
Bcollect += light_color[2] * light_scale + weight_scale;
*/
num_lights++;
} // if dist< radius
@ -220,14 +256,70 @@ do_poly_light(const CullTraverserData *data, const TransformState *node_transfor
}
if (num_lights) {
pgraph_cat.debug() << "num lights = " << num_lights << endl;
// divide by number of lights to get average.
r = Rcollect / num_lights;
g = Gcollect / num_lights;
b = Bcollect / num_lights;
//was_under_polylight = true;
//data->_node_path.get_node_path().set_color_scale_off();
if (polylight_info)
pgraph_cat.info() << "r=" << r << "; g=" << g << "; b=" << b << endl;
pgraph_cat.info() << "num lights = " << num_lights << endl;
// divide by number of lights to get average.
r = Rcollect;// / num_lights;
g = Gcollect;// / num_lights;
b = Bcollect;// / num_lights;
if (polylight_info)
pgraph_cat.info() << "avg: r=" << r << "; g=" << g << "; b=" << b << endl;
// Now add the scene_color multiplied by weight_scale
r += scene_color[0] * weight_scale;
g += scene_color[1] * weight_scale;
b += scene_color[2] * weight_scale;
if (polylight_info)
pgraph_cat.info() << "weighed: r=" << r << "; g=" << g << "; b=" << b << endl;
/*
// normalize the color
LVector3f color_vector(r, g, b);
color_vector.normalize();
r = color_vector[0];
g = color_vector[1];
b = color_vector[2];
if (polylight_info)
pgraph_cat.info() << "unit: r=" << r << "; g=" << g << "; b=" << b << endl;
*/
// cap it
r = (r > 1.0)? 1.0 : r;
g = (g > 1.0)? 1.0 : g;
b = (b > 1.0)? 1.0 : b;
if (polylight_info)
pgraph_cat.info() << "capped: r=" << r << "; g=" << g << "; b=" << b << endl;
// since this rgb will be scaled by scene_color by day night
// cycle, lets undo that effect by dividing this rgb by the
// scene_color. That way, the final render will contain this rgb
if (scene_color[0] >= 0.01)
r /= scene_color[0];
if (scene_color[1] >= 0.01)
g /= scene_color[1];
if (scene_color[2] >= 0.01)
b /= scene_color[2];
if (polylight_info)
pgraph_cat.info() << "final: r=" << r << "; g=" << g << "; b=" << b << endl;
}
/*
else {
if (was_under_polylight) {
// under no polylight influence...so clear the color scale
//data->_node_path.get_node_path().clear_color_scale();
//data->_node_path.get_node_path().set_color_scale(scene_color);
was_under_polylight = false;
}
}
*/
return ColorScaleAttrib::make(LVecBase4f(r, g, b, 1.0));
}