public Vector3 GetSoftShadowLight(LightSphere lp, HitPoint hitPoint, Vector3 sphereColor)
{
Vector3 shadowLight = Vector3.Zero;
Vector3 NL = Vector3.Normalize(hitPoint._point - lp._position);
Vector3 Nx = Vector3.Normalize(Vector3.Cross(NL, _up));
Vector3 Ny = Vector3.Cross(NL, Nx);
int numOfCalc = 20;
int hits = 0;
for (int i = 0; i < numOfCalc; i++)
{
Vector3 P = lp._position + lp._Radius * GetRandomNumber(0f, 1f) * Nx + Ny * GetRandomNumber(0f, 1f) * lp._Radius;
Ray lightRay = new Ray(hitPoint._point, Vector3.Normalize(P - hitPoint._point));
lightRay._origin += lightRay._direction * 0.001f;
HitPoint shadowHitpoint = FindClosestHitPoint(lightRay);
if (shadowHitpoint != null && (shadowHitpoint._point - hitPoint._point).Length() < (lp._position - hitPoint._point).Length())
{
hits++;
shadowLight = lp._color * sphereColor * 0.7f;
}
}
shadowLight = shadowLight * hits / numOfCalc;
return(shadowLight);
}
public static Vector3 GetSpecularLight(float nL, HitPoint hitPoint, Vector3 lightColor, Vector3 r, Vector3 EH)
{
Vector3 specularLight = Vector3.Zero;
if (nL >= 0)
{
float phongFactor = Vector3.Dot(r, Vector3.Normalize(hitPoint._point - _eye));
specularLight = lightColor * (float)Math.Pow(phongFactor, _k);
}
return(specularLight);
}
public Vector3 GetShadowLight(LightSource light, HitPoint hitPoint, Vector3 sphereColor)
{
Vector3 shadowLight = Vector3.Zero;
Ray lightRay = new Ray(hitPoint._point, Vector3.Normalize(light._position - hitPoint._point));
lightRay._origin += lightRay._direction * 0.001f;
HitPoint shadow = FindClosestHitPoint(lightRay);
if (shadow != null && (shadow._point - hitPoint._point).Length() < (light._position - hitPoint._point).Length())
{
shadowLight = light._color * sphereColor;
}
return(shadowLight);
}
public Vector3 CalcColour(CheckBoxControl checkBoxControl, Ray ray, int reflectionFactor = 0)
{
HitPoint hitpoint = null;
Vector3 color = Vector3.Zero;
Vector3 diffColor = Vector3.Zero;
if (checkBoxControl.ISBVHAccelerationCheckBoxChecked)
{
BVHSphere root = (BVHSphere)_spheres.First();
hitpoint = FindClosestHitPointBHV(ray, root);
LightSource light = new LightSource(new Vector3(0.0f, -0.9f, 0), new Vector3(1.0f, 1.0f, 1.0f));
Vector3 n = Vector3.Normalize(hitpoint._point - hitpoint._sphere._center);
Vector3 l = Vector3.Normalize(Vector3.Subtract(light._position, hitpoint._point));
float nL = Vector3.Dot(n, l);
return(color = GetDiffuseLight(nL, light._color, hitpoint._color));
}
else
{
hitpoint = FindClosestHitPoint(ray);
}
// No hitpoint found
if (hitpoint == null || hitpoint._sphere == null)
{
return(Vector3.Zero);
}
// Case 5: Reflections
if (checkBoxControl.IsReflectionCheckBoxChecked)
{
if (hitpoint._sphere._reflection && _reflectionStep < 10)
{
Vector3 l1 = Vector3.Normalize(_eye - hitpoint._point);
Vector3 n2 = Vector3.Normalize(hitpoint._point - hitpoint._sphere._center);
Vector3 r2 = 2 * (Vector3.Dot(l1, n2)) * n2 - l1;
Vector3 col = CalcColour(checkBoxControl, new Ray(_eye, r2), _reflectionStep + 1);
return(color += col);
}
}
// Case 8: Soft shadows
if (checkBoxControl.IsSoftShadowCheckBoxChecked)
{
LightSphere lp = new LightSphere(new Vector3(0.0f, -0.9f, 0), new Vector3(1.0f, 1.0f, 1.0f), 0.2f);
Vector3 n = Vector3.Normalize(hitpoint._point - hitpoint._sphere._center);
Vector3 l = Vector3.Normalize(Vector3.Subtract(lp._position, hitpoint._point));
float nL = Vector3.Dot(n, l);
Vector3 s = l - Vector3.Dot(l, n) * n;
Vector3 EH = Vector3.Normalize(Vector3.Subtract(_eye, hitpoint._point));
Vector3 r = Vector3.Normalize(l - 2 * s);
color += GetDiffuseLight(nL, lp._color, hitpoint._color);
color += GetSpecularLight(nL, hitpoint, lp._color, r, EH);
color -= GetSoftShadowLight(lp, hitpoint, hitpoint._color);
return(color);
}
foreach (LightSource light in _lighting._lights)
{
// Get overall settings
Vector3 n = Vector3.Normalize(hitpoint._point - hitpoint._sphere._center);
Vector3 l = Vector3.Normalize(Vector3.Subtract(light._position, hitpoint._point));
float nL = Vector3.Dot(n, l);
Vector3 s = l - Vector3.Dot(l, n) * n;
Vector3 EH = Vector3.Normalize(Vector3.Subtract(_eye, hitpoint._point));
Vector3 r = Vector3.Normalize(l - 2 * s);
// Case 1: Simple Ray Tracing
//color = hitpoint._color;
// Case 2: Diffuse/Lambert Light
if (checkBoxControl.IsDiffuseCheckBoxChecked)
{
color += GetDiffuseLight(nL, light._color, hitpoint._color);
}
// Case 3: Phong/Specular
if (checkBoxControl.IsSpecularCheckBoxChecked)
{
color += GetSpecularLight(nL, hitpoint, light._color, r, EH);
}
// Case 4: Shadows
if (checkBoxControl.IsShadowCheckBoxChecked)
{
color -= GetShadowLight(light, hitpoint, color);
}
// Case 6: Procedural Textures
//if (checkBoxControl.IsProceduralTextureCheckBoxChecked && hitpoint._sphere._proceduralTexture){ color = ProceduralTexturing.GetProceduralColor(n.X, n.Y, n.Z);}
// Case 7: Bitmap textures
if (checkBoxControl.IsBitmapTextureCheckBoxChecked && hitpoint._sphere._bitmapTexture)
{
color = bitmapTexturing.GetBitmapColor(n.X, n.Y, n.Z);
}
}
return(color);
}