/*
* getPixelColor adds all lights and "shadows" at each point P of the image
*/
public static Couleur getPixelColor(V3 P, Couleur c, V3 N, int object_index)
{
Couleur pixel_color = c;
float decay = 1;
pixel_color = Color_Ambient(c);
foreach (Light_Source light in lights)
{
if (light.point_light)
{
Elements.objects_on_screen[object_index].intersection_RayObject(light.position, P - light.position, out V3 P1, out V3 N1, out float t);
decay = (float)Math.PI / (float)(Math.Pow(t, 2));
if (decay > 1)
{
decay = 1;
}
}
pixel_color += decay * Color_Diffused(light, c, P, N);
decay = 1;
if (Elements.objects_on_screen[object_index].is_spec)
{ // if the light creates a specular effect
pixel_color += Color_Specular(light, P, N, 200);
}
}
pixel_color.check();
return(pixel_color);
}
static void DrawFastPixel(int x, int y, Couleur c)
{
unsafe
{
byte RR, VV, BB;
c.check();
c.To255(out RR, out VV, out BB);
byte *ptr = (byte *)data.Scan0;
ptr[(x * 3) + y * stride] = BB;
ptr[(x * 3) + y * stride + 1] = VV;
ptr[(x * 3) + y * stride + 2] = RR;
}
}
static void DrawFastPixel(int x, int y, Couleur c)
{
unsafe
{
byte RR, VV, BB;
c.check();
c.To255(out RR, out VV, out BB);
byte* ptr = (byte*)data.Scan0;
ptr[(x * 3) + y * stride ] = BB;
ptr[(x * 3) + y * stride + 1] = VV;
ptr[(x * 3) + y * stride + 2] = RR;
}
}
public static Couleur RayTracer(V3 ray_origin, V3 ray_direction, int depth)
{
Object obj = null;
float t = -1, t_min = float.MaxValue;
V3 P_test, N_test, intersection_P, intersection_N;
intersection_P = intersection_N = new V3(0, 0, 0);
for (int i = 0; i < objects_on_screen.Count; i++)
{
if (Elements.objects_on_screen[i].intersection_RayObject(ray_origin, ray_direction, out P_test, out N_test, out t))
{
if (t < t_min && t > 0)
{
obj = Elements.objects_on_screen[i];
intersection_P = P_test;
intersection_N = N_test;
t_min = t;
}
}
}
if (obj == null)
{
return(Black);
}
// if the object material is specular, split the ray into a reflection
// and a refraction ray
if (obj.is_spec && depth < MAX_RAY_DEPTH)
{
Couleur reflectionColor = Black;
// compute reflection
V3 reflectionRay;
Couleur color = obj.getPixelColor(intersection_P);
// recurse
if (obj.reflective_index > 0)
{
reflectionRay = computeReflectionRay(ray_direction, intersection_N);
// recurse
reflectionColor = obj.reflective_index * RayTracer(intersection_P, reflectionRay, depth + 1);
}
V3 refractionRay;
// recurse
if (obj.refractive_index != 0)
{
refractionRay = computeRefractionRay(obj.refractive_index, ray_direction, intersection_N);
Couleur refractionColor = RayTracer(intersection_P, refractionRay, depth + 1);
float Kr = 1, Kt = 1;
fresnel(obj.reflective_index, obj.refractive_index, intersection_N, ray_direction, ref Kr, ref Kt);
color += reflectionColor * Kr + refractionColor * Kt;
//color += refractionColor;
color.check();
return(color);
}
color += reflectionColor;
color.check();
return(color);
}
// object is a diffuse opaque object
// compute color
return(obj.getPixelColor(intersection_P));
}
